[Federal Register Volume 76, Number 111 (Thursday, June 9, 2011)]
[Proposed Rules]
[Pages 33924-33965]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-13910]
[[Page 33923]]
Vol. 76
Thursday,
No. 111
June 9, 2011
Part IV
Department of the Interior
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Fish and Wildlife Service
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50 CFR Part 17
Endangered and Threatened Wildlife and Plants; 12-Month Finding on a
Petition to List Abronia ammophila, Agrostis rossiae, Astragalus
proimanthus, Boechera (Arabis) pusilla, and Penstemon gibbensii as
Threatened or Endangered; Proposed Rule
Federal Register / Vol. 76 , No. 111 / Thursday, June 9, 2011 /
Proposed Rules
[[Page 33924]]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[FWS-R6-ES-2011-0023; MO 92210-0-0008-B2]
Endangered and Threatened Wildlife and Plants; 12-Month Finding
on a Petition To List Abronia ammophila, Agrostis rossiae, Astragalus
proimanthus, Boechera (Arabis) pusilla, and Penstemon gibbensii as
Threatened or Endangered
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of 12-month petition finding.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a
12-month finding on a petition to list Abronia ammophila (Yellowstone
sand verbena), Agrostis rossiae (Ross' bentgrass), Astragalus
proimanthus (precocious milkvetch), Boechera (Arabis) pusilla (Fremont
County rockcress or small rockcress), and Penstemon gibbensii (Gibbens'
beardtongue) as threatened or endangered, and to designate critical
habitat under the Endangered Species Act of 1973, as amended (Act).
After review of all available scientific and commercial information, we
find that listing A. ammophila, A. rossiae, A. proimanthus, and P.
gibbensii is not warranted at this time. However, we ask the public to
submit to us any new information that becomes available concerning the
threats to A. ammophila, A. rossiae, A. proimanthus, and P. gibbensii
or their habitats at any time. After a review of all the available
scientific and commercial information, we find that listing B. pusilla
as threatened or endangered is warranted. However, currently listing B.
pusilla is precluded by higher priority actions to amend the Federal
Lists of Endangered and Threatened Wildlife and Plants. Upon
publication of this 12-month petition finding, we will add B. pusilla
to our candidate species list. We will develop a proposed rule to list
B. pusilla as our priorities allow. We will make any determinations on
critical habitat during development of the proposed listing rule. In
any interim period, we will address the status of the candidate taxon
through our annual Candidate Notice of Review.
DATES: The finding announced in this document was made on June 9, 2011.
ADDRESSES: This finding is available on the Internet at http://www.regulations.gov at Docket Number FWS-R6-ES-2011-0023. Supporting
documentation used in preparing this finding is available for public
inspection, by appointment, during normal business hours at the U.S.
Fish and Wildlife Service, Wyoming Ecological Services Field Office,
5353 Yellowstone Road, Suite 308A, Cheyenne, WY 82009. Please submit
any new information, materials, comments, or questions concerning this
finding to the above address.
FOR FURTHER INFORMATION CONTACT: R. Mark Sattelberg, Field Supervisor,
Wyoming Ecological Services Field Office (see ADDRESSES); by telephone
at 307-772-2374; or by facsimile at 307-772-2358. If you use a
telecommunications device for the deaf (TDD), please call the Federal
Information Relay Service (FIRS) at 800-877-8339.
SUPPLEMENTARY INFORMATION:
Background
Section 4(b)(3)(B) of the Act (16 U.S.C. 1531 et seq.), requires
that, for any petition to revise the Federal Lists of Endangered and
Threatened Wildlife and Plants that contains substantial scientific or
commercial information that listing the species may be warranted, we
make a finding within 12 months of the date of receipt of the petition.
In this finding, we will determine that the petitioned action is: (1)
Not warranted, (2) warranted, or (3) warranted, but the immediate
proposal of a regulation implementing the petitioned action is
precluded by other pending proposals to determine whether species are
threatened or endangered, and expeditious progress is being made to add
or remove qualified species from the Federal Lists of Endangered and
Threatened Wildlife and Plants. Section 4(b)(3)(C) of the Act requires
that we treat a petition for which the requested action is found to be
warranted but precluded as though resubmitted on the date of such
finding, that is, requiring a subsequent finding to be made within 12
months. We must publish these 12-month findings in the Federal
Register.
Previous Federal Actions
Federal action for Agrostis rossiae and Astragalus proimanthus
began as a result of section 12 of the original Act, which directed the
Secretary of the Smithsonian Institution to prepare a report on plants
considered to be endangered, threatened, or extinct in the United
States. This report, designated as House Document No. 94-51, was
presented to Congress on January 9, 1975. That document lists A.
rossiae as a threatened species and A. proimanthus as an endangered
species (House Document 94-51, pp. 57, 90, 163). On July 1, 1975, we
published a notice in the Federal Register (40 FR 27823) accepting the
Smithsonian Institution report as a petition within the context of
section 4(c)(2) (petition provisions are now found in section 4(b)(3)
of the Act), and giving notice of the Service's intention to review the
status of the plant taxa listed therein.
As a result of that review, we published a proposed rule on June
16, 1976, in the Federal Register (41 FR 24523) to determine endangered
status pursuant to section 4 of the Act for approximately 1,700
vascular plant taxa, including Astragalus proimanthus. This list of
plant taxa was assembled based on comments and data received by the
Smithsonian Institution and the Service in response to House Document
No. 94-51 and the July 1, 1975, Federal Register publication. General
comments received in response to the 1976 proposal are summarized in an
April 26, 1978, Federal Register publication (43 FR 17909). In 1978,
amendments to section 4(f)(5) of the Act required that all proposals
over 2 years old be withdrawn. However, proposals already over 2 years
old were given a 1-year grace period. On December 10, 1979, we
published a notice in the Federal Register (44 FR 70796) withdrawing
the portion of the June 16, 1976, proposal that had not been made
final. This removed both A. proimanthus and Agrostis rossiae from
proposed status, but retained both species as candidate plant taxa that
``may qualify for listing under the Act.''
On December 15, 1980, we published a current list of those plant
taxa native to the United States being considered for listing under the
Act; this identified both Agrostis rossiae and Astragalus proimanthus
as category 1 taxa (45 FR 82480). The Service defined category 1 taxa
as a taxonomic group for which we presently had sufficient information
on hand to support the biological appropriateness of these taxa being
listed as threatened or endangered species (45 FR 82480). On November
28, 1983, A. rossiae was lowered to a category 2 taxon ``currently
under review,'' whereas A. proimanthus was moved to the ``taxa no
longer under review'' list, and given a 3C rank, indicating the species
was more abundant or widespread than previously believed or not
subjected to any identifiable threat (48 FR 53640). We defined category
2 taxa as those for which we had information at that time that
indicated proposing to list was possibly appropriate, but for which
substantial data on biological
[[Page 33925]]
vulnerability and threat(s) was not currently known or on file to
support proposed rules. Boechera (formerly Arabis) pusilla and
Penstemon gibbensii were added as category 2 taxa during the same
review (48 FR 53640). These four species retained the same ranking for
the subsequent review on September 27, 1985 (50 FR 39526). The February
21, 1990, list kept A. rossiae, B. pusilla, and P. gibbensii as
category 2 taxa, and reverted A. proimanthus back to a category 2 taxon
(55 FR 6184).
The September 30, 1993, review changed the status of Boechera
pusilla to a category 1 species (58 FR 51144). This review added a
``status trend'' column. Each species was identified as increasing (I),
stable (S), declining (D), or unknown (U). The 1993 review added
Abronia ammophila and assigned it a 2U rank, moved Boechera pusilla up
to a 1D rank, and listed Agrostis rossiae as 2U, Astragalus proimanthus
as 2S, and Penstemon gibbensii as 2U (58 FR 51144).
On February 28, 1996, we proposed discontinuing the designation of
category 2 species as candidates due to the lack of sufficient
information to justify issuance of a proposed rule (61 FR 7596). This
proposal included eliminating candidate status for four of the five
species addressed in this finding; only Boechera pusilla was proposed
to remain a candidate (61 FR 7596). This policy change was finalized on
December 5, 1996, stating that the listing of category 2 species was
not needed because of other lists already maintained by other entities
such as Federal and State agencies (61 FR 64481).
On September 19, 1997, we published a notice of review that
retained Boechera pusilla as a candidate species (62 FR 49398).
However, on October 25, 1999, we published a notice of review that
indicated our intent to remove several species, including B. pusilla,
from the list of candidate species because evidence suggested that
these taxa were either more abundant than previously believed or that
the taxa were not subject to the degree of threats sufficient to
warrant continuance of candidate status, issuance of a proposed
listing, or a final listing (64 FR 57534). The change of status for B.
pusilla was finalized on October 20, 2000, on the basis that regulatory
mechanisms and changes to management of the associated land reduced or
eliminated the threats facing B. pusilla and ensured the survival and
conservation of this species (65 FR 63044).
On July 30, 2007, we received a formal petition dated July 24,
2007, from Forest Guardians (now WildEarth Guardians), requesting that
we: (1) Consider all full species in our Mountain-Prairie Region ranked
as G1 or G1G2 by the organization NatureServe, except those that are
currently listed, proposed for listing, or candidates for listing; and
(2) list each species as either threatened or endangered. The petition
identified 206 species as petitioned entities, including the 5 species
we address in this status review. A species ranking of G1 is defined as
a species that is critically imperiled across its entire range (or
global range) (NatureServe 2010b, p. 3). A ranking of G1G2 means the
species is either ranked as a G1 or a G2 species, with G2 defined as
imperiled across its entire range (NatureServe 2010b, pp. 3-4). The
petition incorporated all analysis, references, and documentation
provided by NatureServe in its online database at http://www.natureserve.org/ into the petition. The petition clearly identified
itself as a petition and included the identification information, as
required in 50 CFR 424.14(a). We sent a letter to the petitioners,
dated August 24, 2007, acknowledging receipt of the petition and
stating that, based on preliminary review, we found no compelling
evidence to support an emergency listing for any of the species covered
by the petition.
On March 19, 2008, WildEarth Guardians filed a complaint (1:08-CV-
472-CKK) indicating that the Service failed to comply with its
mandatory duty to make a preliminary 90-day finding on their two
multiple-species petitions--one for mountain-prairie species and one
for southwest species. We subsequently published two initial 90-day
findings on January 6, 2009 (74 FR 419), and February 5, 2009 (74 FR
6122). The February 5, 2009, finding determined that there was not
substantial scientific or commercial information indicating that
listing 165 of the 206 petitioned species in the mountain-prairie
region may be warranted (74 FR 6122). Two additional species were
evaluated in a January 6, 2009, 90-day finding (74 FR 419), and no
determination was made on whether substantial information had been
presented on the remaining 39 species included in the petition (74 FR
6122). The 5 species covered in this 12-month finding were among the
remaining 39 species. An additional species was determined to qualify
for candidate status (73 FR 75175; December 10, 2008). On March 13,
2009, the Service and WildEarth Guardians filed a stipulated settlement
in the District of Columbia Court, agreeing that the Service would
submit to the Federal Register a finding as to whether WildEarth
Guardians' petitions present substantial information indicating that
the petitioned actions may be warranted for the remaining 38 mountain-
prairie species by August 9, 2009.
On June 18, 2008, we received a petition from WildEarth Guardians
dated June 12, 2008, to emergency list 32 species under the
Administrative Procedure Act and the Endangered Species Act. Of those
32 species, 11 were included in the July 24, 2007, petition to be
listed on a non-emergency basis. Although the Act does not provide for
a petition process for an interested person to seek to have a species
emergency listed, section 4(b)(7) of the Act authorizes the Service to
issue emergency regulations to temporarily list a species. In a letter
dated July 25, 2008, we stated that the information provided in both
the 2007 and 2008 petitions and in our files did not indicate that an
emergency situation existed for any of the 11 species. The Service's
decisions whether to exercise its authority to issue emergency
regulations to temporarily list a species are not judicially
reviewable. See Fund for Animals v. Hogan, 428 F.3d 1059 (DC Cir.
2005).
On August 18, 2009, we published a notice of 90-day finding (74 FR
41649) on the remaining 38 species from the petition to list 206
species in the mountain-prairie region of the United States as
threatened or endangered under the Act. We found that the petition
presented substantial scientific and commercial information for 29 of
the 38 species, indicating that listing may be warranted for those
species. The 5 species we address in this 12-month finding were
included within these 29 species. We also opened a 60-day public
comment period to allow all interested parties an opportunity to
provide information on the status of the 29 species (74 FR 41649). The
public comment period closed on October 19, 2009. We received 224
public comments. Of these, 38 specifically addressed Abronia ammophila,
Agrostis rossiae, Astragalus proimanthus, Boechera pusilla, and
Penstemon gibbensii. All information received has been carefully
considered in this finding. This notice constitutes the 12-month
finding on 5 of the 206 species identified in WildEarth Guardians'
petition dated July 24, 2007, to list Abronia ammophila, Agrostis
rossiae, Astragalus proimanthus, Boechera pusilla, and Penstemon
gibbensii as threatened or endangered.
[[Page 33926]]
Summary of Procedures for Determining the Listing Status of Species
Review of Status Based on Five Factors
Section 4 of the Act (16 U.S.C. 1533) and implementing regulations
(50 CFR part 424) set forth procedures for adding species to, removing
species from, or reclassifying species on the Federal Lists of
Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of
the Act, a species may be determined to be endangered or threatened
based on any of the following five factors:
(A) The present or threatened destruction, modification, or
curtailment of its habitat or range;
(B) Overutilization for commercial, recreational, scientific, or
educational purposes;
(C) Disease or predation;
(D) The inadequacy of existing regulatory mechanisms; or
(E) Other natural or manmade factors affecting its continued
existence.
In making these findings, information pertaining to each species in
relation to the five factors provided in section 4(a)(1) of the Act is
discussed below. In considering what factors might constitute threats
to a species, we must look beyond the exposure of the species to a
particular factor to evaluate whether the species may respond to the
factor in a way that causes actual impacts to the species. If there is
exposure to a factor and the species responds negatively, the factor
may be a threat, and during the status review, we attempt to determine
how significant a threat it is. The threat is significant if it drives
or contributes to the risk of extinction of the species such that the
species warrants listing as endangered or threatened as those terms are
defined by the Act. However, the identification of factors that could
impact a species negatively may not be sufficient to compel a finding
that the species warrants listing. The information must include
evidence sufficient to suggest that the potential threat has the
capacity (i.e., it should be of sufficient magnitude and extent) to
affect the species' status such that it meets the definition of
endangered or threatened under the Act.
Findings
Distinct Population Segments
After considering the five factors, we assess whether each species
is threatened or endangered throughout all of its range. Generally, we
next consider in our findings whether a distinct vertebrate population
segment (DPS) or any significant portion of the species' range meets
the definition of endangered or is likely to become endangered in the
foreseeable future (threatened). Section 3(16) of the Act defines a
species to include only a vertebrate species as a DPS. Therefore, the
Service's Policy Regarding the Recognition of Distinct Vertebrate
Population Segments Under the Endangered Species Act (DPS Policy) (61
FR 4722; February 7, 1996) is not applicable to plants and no
population segments under the review could qualify as DPSs under the
Act. Although the Service's DPS Policy is not applicable to plants, we
do determine in our findings whether a plant species is threatened or
endangered in a significant portion of its range.
Significant Portion of the Range
In determining whether a species is threatened or endangered in a
significant portion of its range, we first identify any portions of the
range of the species that warrant further consideration. The range of a
species can theoretically be divided into portions an infinite number
of ways. However, there is no purpose to analyzing portions of the
range that are not reasonably likely to be both (1) significant and (2)
threatened or endangered. To identify only those portions that warrant
further consideration, we determine whether there is substantial
information indicating that: (1) The portions may be significant, and
(2) the species may be in danger of extinction there or likely to
become so within the foreseeable future. In practice, a key part of
this analysis is whether the threats are geographically concentrated in
some way. If the threats to the species are essentially uniform
throughout its range, no portion is likely to warrant further
consideration. Moreover, if any concentration of threats applies only
to portions of the species' range that are not significant, such
portions will not warrant further consideration.
If we identify portions that warrant further consideration, we then
determine whether the species is threatened or endangered in these
portions of its range. Depending on the biology of the species, its
range, and the threats it faces, the Service may address either the
significance question or the status question first. Thus, if the
Service considers significance first and determines that a portion of
the range is not significant, the Service need not determine whether
the species is threatened or endangered there. Likewise, if the Service
considers status first and determines that the species is not
threatened or endangered in a portion of its range, the Service need
not determine if that portion is significant. However, if the Service
determines that both a portion of the range of a species is significant
and the species is threatened or endangered there, the Service will
specify that portion of the range as threatened or endangered under
section 4(c)(1) of the ESA.
Evaluation of the Status of Each of the Five Plant Species
For each of the five species, we provide a description of the
species and its life-history and habitat, an evaluation of listing
factors for that species, and our finding that the petitioned action is
warranted or not for that species. We follow these descriptions,
evaluations, and findings with a discussion of the priority and
progress of our listing actions.
Species Information for Abronia ammophila
Species Description
Abronia ammophila is a low-growing, mat-forming perennial herb
(Clark et al. 1989, p. 7; Fertig 1994, unpaginated; (National Park
Service (NPS) 1999b, p. 3; Fertig 2000b, unpaginated; Saunders and
Sipes 2006, p. 76). A. ammophila is a highly restricted endemic
(occurring only in one location or region) to the Yellowstone Plateau
(NPS 1999a, p. 1). In addition to the common name of Yellowstone sand
verbena, A. ammophila has been called Tweedy's sand verbena (Clark et
al. 1989, p. 7; Marriott 1993, p. 1) and Wyoming sand verbena
(Integrated Taxonomic Information System 2010a, unpaginated).
Abronia ammophila has a large taproot (primary root that grows
vertically downward, not highly branched) that can be over 0.5 meter
(m) (1.6 feet (ft)) in length, which helps the plant root into the
loose sand (Whipple 1999, p. 3; Whipple 2002, p. 257; Saunders and
Sipes 2004, p. 9). Its stems can grow up to 2 to 4 decimeters (dm)
(0.66 to 1.31 ft) in length; however, this plant is only 2.5 to 10.2
centimeters (cm) (1 to 4 inches (in.)) tall (Rydberg 1900, p. 137;
Galloway 1975, p. 344; Fertig 1994, unpaginated; NPS 1999b, p. 3;
Fertig 2000b, unpaginated; NPS 2000, unpaginated). A. ammophila is
covered by sticky glands, which result in the plants being covered with
sand (Coulter and Nelson 1909, p. 175; NPS 1999b, p. 3; NPS 2000,
unpaginated; Whipple 2002, pp. 257-258; Saunders and Sipes 2006, p.
76). The leaf blades are succulent (fleshy) and oval or diamond-shaped
with smooth edges (Fertig 1994, unpaginated; NPS 1999b, p. 3).
[[Page 33927]]
The flowers of Abronia ammophila are whitish to light pink or light
green and grow in a capitulum (head-like group of flowers) typically
containing 4 to 21 flowers (Saunders and Sipes 2006, p. 79). The
flowers are hermaphroditic (possessing both male and female
reproductive organs) (Saunders and Sipes 2004, p. 9; 2006, p. 76). As
with other members of the Nyctaginaceae (the Four O'Clock) family, A.
ammophila lacks true petals (Saunders and Sipes 2004, p. 9; 2006, p.
76).
Discovery and Taxonomy
Frank Tweedy made the first collection of Abronia ammophila in
1885; however, he labeled it as Abronia villosa (desert sand verbena).
The collection was from the sandy beaches on the north side of
Yellowstone Lake at the mouth of Pelican Creek (Tweedy 1886, p. 59). A.
villosa is a common purple-flowered species of the American southwest
(Whipple 2002, p. 256). In 1900, Per Axel Rydberg determined that
Tweedy's sample was sufficiently different from other Abronia to
warrant recognition as a unique species; he named it Abronia arenaria
(coastal sand verbena) (NPS 1999b, p. 2; Whipple 1999, p. 3; 2002, p.
256). However, the name A. arenaria had previously been used (NPS
1999b, p. 2; Whipple 1999, p. 2; 2002, p. 256). E.L. Greene proposed
the name A. ammophila for the Yellowstone sand verbena species (Greene
1900 as cited in Whipple 2002, p. 256).
The name Abronia ammophila was formally recognized (Coulter and
Nelson 1909, p. 175); however, midway through the 20th century it was
combined with Abronia fragrans (snowball sand verbena), a widespread
western species (Hitchcock et al. 1964 and Despain 1975 as cited in
Whipple 2002, p. 257). In 1975, a study of the Abronia genus determined
that the Yellowstone species was unique (Galloway 1975, p. 344; NPS
1999b, p. 3; Whipple 2002, p. 257). Plant material collected from scrub
communities of sandy hills near Big Piney, Sublette County, Wyoming,
also was included under A. ammophila (Galloway 1975, p. 344, NPS 1999b,
p. 3; Whipple 2002, p. 257). Further examination revealed that the
specimens from Sublette County are actually Abronia mellifera (white
sand verbena) (Marriott 1993, pp. 6, 9; Fertig 1994, unpaginated).
Abronia ammophila is a member of the New World plant family
Nyctaginaceae that typically lives in warmer climates, such as deserts
and tropical areas (NPS 2000, unpaginated). The genus Abronia contains
approximately 20 to 30 species (NPS 1999b, p. 2, Flora of North America
2010a, unpaginated). Most Abronia occur in the western United States
and Mexico, but some extend into southern Canada and east into the
Great Plains and Texas (NPS 1999b, p. 2). A. ammophila is similar to
Abronia mellifera (Fertig 1994, unpaginated) and Abronia fragrans
(Flora of North America 2010, unpaginated). We recognize A. ammophila
as a valid species and a listable entity.
Biology and Life History
Abronia ammophila starts to flower by the middle of June and
continues producing flowers until a frost occurs that kills its
aboveground parts, usually in late August or early September (NPS
1999b, p. 6; Whipple 1999, p. 3; NPS 2000, unpaginated; Whipple 2002,
p. 258). This extended blooming period is unusual in comparison to
other plants in Yellowstone National Park (YNP) (Whipple 1999, p. 3).
Additionally, unlike many of its associated species, A. ammophila
continues to flower vigorously even after setting fruit (NPS 1999b, p.
6; Whipple 2002, p. 258).
Abronia ammophila is visited by several orders of insects (Saunders
and Sipes 2004, p. 10; 2006, p. 80). The most frequent visitors to A.
ammophila are lepidopterans (butterflies and moths) (Saunders and Sipes
2004, p. 10; 2006, p. 80). Even though Abronia ammophila is visited by
a diverse range of pollinators, the total number of pollinator
visitations is extremely low (Saunders and Sipes 2006, p. 81). The low
level of pollinator visits may be offset by A. ammophila exhibiting a
mixed-mating system (Saunders and Sipes 2004, pp. 6, 10, 12; 2006, p.
82). In addition to cross-pollination facilitated by pollinators, A.
ammophila is able to self-pollinate with or without a pollen vector
(Saunders and Sipes 2004, pp. 6, 10, 12; 2006, pp. 80-82; Whipple
2010b, pers. comm.). Self-pollination is highly likely due to the
floral morphology (the structure of the flower) and the functional
phenology (life cycle) of A. ammophila (Saunders and Sipes 2006, p.
81).
Abronia ammophila is capable of producing large numbers of flowers
(Saunders and Sipes 2004, p. 13). Seed dispersal mechanisms of Abronia
ammophila have not been extensively studied. Primary seed dispersal
appears to occur beneath the parent plant (Saunders and Sipes 2006, p.
79). Seeds also accumulate in depressions of the sand, where the wind
has blown them (NPS 1999b, p. 6; Whipple 2002, p. 258). The sticky
surface of the seeds may facilitate dispersal, for example on the feet
of waterfowl (NPS 1999b, pp. 6-7; Whipple 2002, p. 258). Water also may
facilitate dispersal (Saunders and Sipes 2006, p. 79). As A. ammophila
occurs in locations that are not located adjacent to each other, there
appears to be an effective method of seed dispersal (NPS 1999b, pp. 6-
7; Whipple 2002, p. 258). However, the longevity of A. ammophila seeds
in the seed bank in unknown (NPS 1999b, p. 7; Whipple 2002, p. 258).
Habitat
Abronia ammophila is endemic to YNP, within Park and Teton Counties
of Wyoming (Whipple 2002, p. 256; Fertig 2000b, unpaginated; Saunders
and Sipes 2006, p. 76). Specifically, A. ammophila occurs around
Yellowstone Lake typically within 40 m (131.2 ft) of the shoreline (NPS
1999b, p. 5; Whipple 1999, p. 3; Fertig 2000b, unpaginated; Whipple
2002, p. 262). The plant has been found up to 60 m (196.9 ft) inland
and up to approximately 10 m (32.8 ft) above the high-water line (NPS
1999b, p. 5; Whipple 1999, p. 3; Fertig 2000b, unpaginated; Whipple
2002, p. 262). A. ammophila generally occurs above the high-water mark;
no plants grow in areas that are regularly inundated (NPS 1999b, p. 5;
Whipple 1999, p. 3; 2002, p. 262). Yellowstone Lake is a high-elevation
(2,360 m (7,742 ft)), freshwater lake that was formed by volcanic
activity (Pierce et al. 2007, pp. 131-132; NPS 2006a, unpaginated). The
lake level was originally 61 m (200 ft) higher than its present level,
and the level is not entirely stable (Pierce et al. 2007, pp. 131-132;
NPS 2006a, unpaginated). A. ammophila appears to be able to adapt to
the continually changing boundaries of its habitat as defined by
Yellowstone Lake's fluctuations.
Occurring between the area of beach affected by wave action and the
more densely vegetated areas inland, Abronia ammophila prefers open,
sunny, sparsely vegetated sites (NPS 1999b, p. 5; Whipple 2002, p. 262;
Saunders and Sipes 2006, p. 77). Associated vegetative species include
Phacelia hastata (silver-leaf scorpion-weed), Rumex venosus (veiny
dock), Polemonium pulcherrimum (Jacob's-ladder), and Lupinus argenteus
(silvery lupine) (NPS 1999b, p. 5; Whipple 2002, p. 262; Saunders and
Sipes 2006, p. 77). A. ammophila loses its competitive advantage on
more stable soils or in areas where Artemisia tridentata (big
sagebrush) or Eriogonum umbellatum (sulfur flower buckwheat) occur
(Whipple 2002, p. 262; Saunders and Sipes 2006, p. 77).
Abronia ammophila occurs at four locations around Yellowstone Lake;
these locations are identified as North
[[Page 33928]]
Shore, Rock Point, Pumice Point, and South Arm (NPS 1999a, pp. 3-6; NPS
1999b, pp. 4-5; Whipple 2002, p. 262). These populations cover an area
of 0.6 hectares (ha) (1.48 acres (ac)) (Whipple 2011, pers. comm.). The
populations all occur in loose, unconsolidated (loosely arranged) sand
with a minimal amount of fines (powdered material), gravel, or organic
matter (NPS 1999b, p. 5; Whipple 2002, p. 262; Saunders and Sipes 2006,
p. 77). All sites are located on beach sand except the Pumice Point
site, which occurs on black sand (NPS 1999b, p. 5; Whipple 2002, p.
262). Some of the populations occur in horseshoe-shaped, sandy
depressions (blowouts) (NPS 1999a, p. 3; 1999b, p. 5; Whipple 2002, p.
262; Saunders and Sipes 2006, p. 77). Additionally, the largest
subpopulation in the North Shore area--the ``Thermal'' site--is located
adjacent to a small thermal barren (area where no vegetation grows)
(NPS 1999a, p. 6; NPS 1999b, p. 6). This area hosts an extremely dense
population of Abronia ammophila with some of the largest individuals
(NPS 1999b, p. 6). A. ammophila is able to coexist with thermal
influences; however, most of the populations grow on ground that is not
thermally influenced (NPS 1999a, p. 6).
Distribution and Abundance
Herbarium records show that Abronia ammophila was previously more
widely distributed along the northern shore of Yellowstone Lake (NPS
1999b, p. 9; Whipple 2002, p. 258). Locations such as 0.40 kilometer
(km) (0.25 mile (mi)) west of the mouth of Pelican Creek and several
locations near the current Fishing Bridge development have been
recorded as collection locations of A. ammophila (NPS 1999b, p. 9;
Whipple 2002, pp. 258-259). Many additional areas of the northern
shoreline provide suitable habitat for A. ammophila, such as west of
Pelican Creek to the outlet of the Yellowstone River and Mary Bay (NPS
1999b, p. 9; Whipple 2002, p. 259; Whipple 2010a, pers. comm.).
Construction of the East Entrance Road and the Fishing Bridge
campground, an area that was near the current parking area for the
Fishing Bridge Museum, as well as higher human use may have extirpated
populations of A. ammophila in these areas (NPS 1999b, pp. 8-9; Whipple
2002, pp. 258-259; Whipple 2010a, pers. comm.).
Table 1 below presents available information regarding the four
populations of Abronia ammophila. The 1998-1999 survey was a rigorous
population count (NPS 1999a, entire). The other years were generally
estimates, except for some of the smaller populations where an exact
count was easily obtained (Correy 2009, entire; Whipple 2010d, pers.
comm.).
Table 1--Population Estimates of Abronia ammophila
------------------------------------------------------------------------
Population (year of discovery) Estimated numbers (year)
------------------------------------------------------------------------
North Shore (prior to 1998).............. Approx. 1,000 (early 1990s).
7,978 (1998-1999) rigorous
count.
Approx. 3,600 (2010).
Rock Point (1998)........................ 325 (1998).
120 (2009).
Pumice Point (1998)...................... 22 (1998).
1 (2001).
5 (2009).
24 (2010).
South Arm (1998)......................... 1 (1998).
3 (2005).
2 (2010).
------------------------------
Totals............................... 1,000 (early 1990s) (only
North Shore known).
8,326 (1998-1999) rigorous
count.
2,728 (2009) estimate.
3,626 (2010) estimate.
------------------------------------------------------------------------
References: NPS 1999a, Appendix A; Corry 2009, Table 1; Whipple 2002, p.
259; 2010d pers. comm.
The majority of Abronia ammophila is found in the North Shore
population scattered along a 2.41-km (1.5-mi) stretch of beach on the
northern shoreline of Yellowstone Lake between the mouth of Pelican
Creek and Storm Point (NPS 1999a, p. 3; 1999b, p. 4; Correy 2009, p.
2). This population contains 95 percent or more of all A. ammophila
(NPS 1999a, pp. 2, Appendix A; Whipple 2002, p. 264; Correy 2009, p.
4). Prior to surveys conducted between 1995 and 1999, the North Shore
population of A. ammophila was the only known population (NPS 1999a, p.
3; Correy 2009, p. 2). Of the additionally discovered sites, two are
located on the west shore of Yellowstone Lake: One at Rock Point, and
one at a picnic area 1.6 km (1 mi) west of Pumice Point (NPS 1999a, p.
5; NPS 1999b, p. 4). Additionally, a single plant was found during
surveys on the east shore of the South Arm (NPS 1999a, p. 5). Not all
suitable habitat within YNP has been surveyed (NPS 1999a, pp. 6-7).
Casual surveys of the North Shore area in the early 1990s estimated
the population to be around 1,000 plants (Correy 2009, pp. 1-2), with
the majority of the plants of a large-size class representing mature,
older plants (NPS 1999a, p. 1; 1999b, p. 7). No seedlings were observed
(NPS 1999b, p. 7). Extensive surveys during the 1998-1999 field seasons
conservatively estimated the North Shore population to consist of 7,978
Abronia ammophila plants, with 45 percent of the population represented
by young recruitment within the prior 2 years (recruit and medium class
plants) (NPS 1999a, p. 1). The record high lake levels of 1996 and 1997
appeared to improve the habitat conditions for A. ammophila by eroding
the southern edge of the stabilized sand along the northern shoreline
(NPS 1999b, p. 7; Whipple 2002, p. 265). Although this erosion washed
away part of the existing habitat, it also improved conditions for
recruitment of seedlings (NPS 1999b, p. 7; Whipple 2002, p. 265).
During the 2009-2010 field season, surveys of the North Shore
population yielded an approximate count of 3,600 A. ammophila plants
(Correy 2009, p. 3; Whipple 2010d, pers. comm.; Whipple 2011, pers.
comm.). The North Shore population can be split into four
subpopulations (Correy 2009, p. 2). Two of these subpopulations had
comparable population counts during both the 1998-1999 survey and the
2009-2010 estimate (Correy 2009, pp. 3-4). The remaining two
subpopulations, the Thermal and Long Skinny groups, had decreased in
both total area populated and total number of plants (Correy 2009, p.
5). The central portion of the Thermal group is now bare or mostly bare
sand due to increased ground temperatures (due to changes within the
Yellowstone geothermal basin), ground subsidence, increased scouring
during storms, or a combination of such factors (Correy 2009, p. 5).
The Long Skinny group also may have been affected by increased ground
temperatures, particularly on the western end; furthermore, some of the
habitat may have eroded (Correy 2009, p. 5). Additional factors
potentially affecting the low population count include many years of
drought (Whipple 2002, p. 265; Correy 2009, pp. 5-6) and lack of
rigorous survey methods (Correy 2009, pp. 5-6).
The Rock Point and Pumice Point Abronia ammophila populations were
accurately counted in 1998 and 2009 (Correy 2009, Table 1). In 1998,
the Rock Point population consisted of 324 individual plants; the 2009
survey counted 120 individual plants (NPS 1999a, p. 6; Correy 2009,
Table 1). An area of Rock Point surveyed in 1998 had no A. ammophila in
June, but contained many medium-sized plants later in the summer (NPS
1999a, p. 6). The Pumice Point population consisted of 22 plants in
1998, whereas only 5 were counted in 2009 (NPS 1999a, p. 6; Correy
2009,
[[Page 33929]]
Table 1). In 1998, the Pumice Point population contained a higher
percentage of large (diameter greater than or equal to 5 up to 30 cm (2
up to 11.8 in.)) and very large (diameter greater than or equal to 30
cm (11.8 in.)) plants when compared to the North Shore population
distribution (NPS 1999a, p. 6). Additionally, the Pumice Point
population contained 24 plants in the 2010 field survey (Whipple 2010e,
pers. comm.), which is comparable to the 1998 population count.
The South Arm population contained only one large Abronia ammophila
plant when it was discovered in 1998 (NPS 1999a, p. 6). When this site
was revisited in 2005, the large individual found in 1998 was no longer
present, but three small A. ammophila plants were present (Correy 2009,
p. 2). Additionally, during the 2010 field survey, this population
consisted of two plants (Whipple 2010e, pers. comm.).
Dead and dying plants were counted during the 1998-1999 field
surveys. Dead and dying Abronia ammophila plants accounted for 1.3
percent of the total population (NPS 1999a, Appendix A). Of the dead A.
ammophila plants, many were large individuals; however, some were
failed seedlings (NPS 1999b, p. 7). The majority of dead and dying
plants did not display obvious causes of mortality; they were
interspersed throughout the communities (NPS 1999b, p. 7).
Additionally, stressed A. ammophila plants are able to recover and put
out new growth later in the season (NPS 1999b, p. 7).
The Wyoming Natural Diversity Database (WNDD) has designated
Abronia ammophila as a plant species of concern with ranks of G1 and S1
(Heidel 2007, p. 1). This designation indicates that A. ammophila is
considered to be critically imperiled because of extreme rarity (i.e.,
often less than five occurrences (a location where a plant or plants
has been recorded)) or because some factor makes it highly vulnerable
to extinction both at the global and State level; however, this ranking
does not grant A. ammophila any special status under State legislation
(WNDD 2009, unpaginated; WNDD 2010, unpaginated). Since A. ammophila is
endemic to Wyoming, the Wyoming occurrences encompass the entire global
range. Additionally, YNP considers A. ammophila to be a sensitive
species of concern; therefore, it evaluates effects to this species in
conjunction with any project or action that has the potential to affect
the plant (Whipple 2011, pers. comm.).
Trends
Natural fluctuations in the Abronia ammophila population from year
to year or even within a season are not understood (Correy 2009, p. 6).
From the first population estimates of the North Shore population in
the early 1990s to the more rigorous survey conducted in 1998-1999,
there was extensive recruitment and the A. ammophila population
increased approximately 87 percent (NPS 1999a, p. 1; Correy 2009, pp.
6, Table 1). Notably, 1996 and 1997 had high precipitation, with
resultant high lake levels (NPS 1999a, p. 2). The 1998-1999 surveys
recorded approximately 20 percent of the population to be seedlings or
recruit size class (NPS 1999a, Appendix A). The 2009 population
estimate of the North Shore populations shows a decrease from the 1998-
1999 survey (Correy 2009, Table 1). However, the 1998-1999 survey was
an exact count, whereas the 2009 was an estimate. Additionally, the
subsequent 2010 population estimate shows a slight increase in the
population size compared to the 2009 population estimate (Whipple
2010e, pers. comm.). Hypotheses for population fluctuations are
changing thermal activity of the underlying area, ground subsidence,
changing precipitation levels, and human and animal activity (Correy
2009, pp. 5-6). The A. ammophila population seems to be stable within
the parameters of a population that lives in an unstable habitat that
fluctuates with wave action and weather (Whipple 2010a, pers. comm.).
Five Factor Evaluation for Abronia ammophila
Information pertaining to Abronia ammophila in relation to the five
factors provided in section 4(a)(1) of the Act is discussed below.
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
Potential factors that may affect the habitat or range of Abronia
ammophila are discussed in this section, including: (1) Development,
(2) trampling, (3) nonnative invasive plants, (4) climate change, and
(5) drought.
Development
Abronia ammophila occurs entirely inside YNP, which limits
potential threats to its habitat. By statute, regulation, and policy,
YNP conserves wildlife and habitat; preserves and maintains biological
processes, ecosystem components, and ecological integrity; controls
invasive plants; and protects and monitors populations of sensitive
plants and animals (See Yellowstone National Park under Factor D. The
Inadequacy of Existing Regulatory Mechanisms in this Five Factor
Evaluation for Abronia ammophila section). YNP was established prior to
the States in which it is located (Mazzu 2010, pers. comm.; Whipple
2010e, pers. comm.). This means that YNP owns not only the land, but
also the mineral rights; therefore, energy development is not a threat
(Mazzu 2010, pers. comm.; Whipple 2010e, pers. comm.). Construction of
new roads, trails, or structures within YNP is rare, with
reconstruction of existing features occurring occasionally. When new
construction or reconstruction occurs in areas where there are
sensitive species, YNP analyzes and carries out construction in a
manner that minimizes adverse effects. A. ammophila populations are
located a sufficient distance from roads; therefore, road
reconstruction does not impact any of the A. ammophila populations
(Whipple 2010e, pers. comm.).
As noted above (see Distribution and Abundance), Abronia ammophila
has been extirpated in some areas in which there is no longer habitat
due to the construction of roads or structures. However, the
construction in these areas occurred prior to YNP identifying A.
ammophila as a species of conservation concern. Now, when new
construction or reconstruction occurs, YNP analyzes and carries out
construction in a manner that avoids adverse effects to sensitive
species. Additionally, projects must be accompanied by a Resource
Compliance Checklist that requires the evaluation of any potential
impacts to resources including rare plants; if there are impacts,
mitigation measures are developed (Schneider 2010, pers. comm.). The
majority of YNP remains undeveloped, and we have no information that
this will change; therefore, we do not consider development to be a
threat to the species now or in the foreseeable future.
Trampling
Trampling of Abronia ammophila, by both humans and wildlife, is a
potential concern at most sites (Whipple 2010a, pers. comm.). The
Abronia genus is vulnerable to disturbance by trampling (NPS 1999b, p.
8; Whipple 2010e, pers. comm.). Trampling is frequently indicated as a
threat to A. ammophila (e.g., NPS 1999a; 1999b); however, studies that
seek to document trampling indicate that there is very little foot
traffic actually impacting the populations of A. ammophila (NPS 1999a,
pp. 2, 5).
[[Page 33930]]
The North Shore population is located in one of the least visited
portions of the north side of Yellowstone Lake's shoreline (NPS 1999b,
p. 8). A large wetland restricts access to this site from the west (NPS
1999b, p. 8). The Storm Point Trail approaches the east end of the
North Shore population, and visitors occasionally walk down the beach
toward this population (NPS 1999b, p. 8). The YNP plans to install a
sign just past the Storm Point Trail requesting that visitors remain
near the water and avoid sensitive vegetation areas (Schneider 2010,
pers. comm.).
The Pelican Creek Nature Trail is also near the North Shore
population (Schneider 2010, pers. comm.). No plants currently occur in
this area; however, it is historical habitat (Whipple 2010a, pers.
comm.; Schneider 2010, pers. comm.). YNP is currently considering
conservation measures, including closing all or part of this trail to
protect the potential habitat (Whipple 2010a, pers. comm.; Schneider
2010, pers. comm.). A final decision, on this trail, has not been made
at this time (Whipple 2011, pers. comm.).
The Pumice Point population of Abronia ammophila is located near an
unmarked picnic area; the plants are located within 10 m (32.8 ft) of
the picnic tables (NPS 1999b, p. 8). This area is currently unsigned
(not marked as a picnic area from the main road), and the entrance is
inconspicuous (Whipple 2010c, pers. comm.). Additionally, the A.
ammophila in this area may be benefiting from the disturbance; if foot
traffic did not occur, the area might be more densely vegetated and not
available as habitat for A. ammophila (NPS 1999b, p. 8; Whipple 2010c,
pers. comm.).
The two remaining populations are in areas with little visitation
(NPS 1999b, p. 8). The Rock Point population is approximately a half-
hour walk from the closest access point (Whipple 2010c, pers. comm.).
The South Arm population is accessible by boat, with a backcountry
campsite located about 200 m (656.2 ft) from the population (Whipple
2010c, pers. comm.). This backcountry campsite has no trail access
(Whipple 2010c, pers. comm.).
YNP has received approximately 3 million visitors a year for the
past 20 years; visitation was over 3 million for 11 of those years (NPS
2010a, unpaginated). From January to September of 2010, YNP received
3.4 million visitors, an increase of 8.7 percent over the previous year
(NPS 2010b, unpaginated). Even with increases to visitation, we have no
information indicating that the number of visitors correlates with
increased trampling of Abronia ammophila populations to a level that
poses a threat to the species.
Wildlife trampling, particularly by ungulates, is occasionally
indicated as a concern (Whipple 2010a, pers. comm.) We believe that
these anecdotal observations do not add up to routine impacts on a
scale that would cause the species to be threatened or endangered.
Additionally, we believe that trampling by wildlife represents a
natural ecological interaction in YNP that the species would have
evolved with and poses no threat to long-term persistence.
In summary, the populations of Abronia ammophila are located in
areas of YNP that do not receive the bulk of visitor traffic. When
surveys have attempted to document trampling by humans, observers had
determined that the impact is minor. We have only anecdotal evidence of
wildlife trampling. Therefore, we have no information indicating that
trampling by either humans or wildlife is a threat to the species now
or in the foreseeable future.
Nonnative Invasive Plants
After habitat loss, the spread of nonnative invasive species is
considered the second largest threat to imperiled plants in the United
States (Wilcove et al. 1998, p. 608). Nonnative invasive plants alter
ecosystem attributes including geomorphology, fire regime, hydrology,
microclimate, nutrient cycling, and productivity (Dukes and Mooney
2004, pp. 411-437). Nonnative invasive plants can detrimentally affect
native plants through competitive exclusion, altered pollinator
behaviors, niche displacement, hybridization, and changes in insect
predation (D'Antonio and Vitousek 1992, pp. 74-75; DiTomaso 2000, p.
257; Mooney and Cleland 2001, p. 5449; Levine et al. 2003, p. 776;
Traveset and Richardson 2006, pp. 211-213).
As of 2010, YNP has documented 218 nonnative plant species
occurring within its boundaries (NPS 2010e, p. 1). Encroachment of
invasive plants may potentially affect A. ammophila, as this species
prefers open, sparsely vegetated sites and does not compete well in
areas that are more densely vegetated.
Currently, nonnative invasive plants have affected only a few sites
occupied by Abronia ammophila (NPS 1999b, p. 8; Whipple 2010a, pers.
comm.). The invasive grass Bromus tectorum (cheatgrass) has been noted
in the vicinity of the North Shore population, and Cirsium arvense
(Canada thistle) occurs near the Rock Point population (Whipple 2010a,
pers. comm.). Additionally, some B. tectorum was documented around the
Storm Point population (NPS 1999b, p. 8). To combat these occurrences,
YNP has an exotic vegetation management plan in place that emphasizes
prevention, education, early detection and eradication, control, and
monitoring (Olliff et al. 2001, entire).
In summary, nonnative invasive plants occur within YNP; however,
the majority of these species do not impact the habitat of Abronia
ammophila. A few nonnative invasive species have been documented near
the habitat of A. ammophila. These species are being monitored and the
National Park System (NPS) has mechanisms in place to help control
these encroachments. We have no information indicating that nonnative
invasive species are modifying the species habitat to the extent that
it represents a threat to the species now or in the foreseeable future.
Climate Change
The Intergovernmental Panel on Climate Change (IPCC) was
established in 1988 by the World Meteorological Organization and the
United Nations Environment Program in response to growing concerns
about climate change and, in particular, the effects of global warming.
The IPCC Fourth Assessment Report (IPCC 2007, entire) synthesized the
projections of the Coupled Model Intercomparison Project (CMIP) Phase
3, a coordinated large set of climate model runs performed at modeling
centers worldwide using 22 global climate models (Ray et al. 2010, p.
11). Based on these projections, the IPCC has concluded that the
warming of the climate system is unequivocal, as evidenced from
observations of increases in global average air and ocean temperatures,
widespread melting of snow and ice, and rising global average sea level
(IPCC 2007, pp. 6, 30; Karl et al. 2009, p. 17). Changes in the global
climate system during the 21st century are likely to be larger than
those observed during the 20th century (IPCC 2007, p. 19). Several
scenarios are virtually certain or very likely to occur in the 21st
century including: (1) Over most land, weather will be warmer, with
fewer cold days and nights, and more frequent hot days and nights; (2)
areas affected by drought will increase; and (3) the frequency of warm
spells and heat waves over most land areas will likely increase (IPCC
2007, pp. 13, 53).
In some cases, climate change effects can be demonstrated and
evaluated (e.g., McLaughlin et al. 2002, p. 6073). Where regional
effects from global climate change have been demonstrated, we can
[[Page 33931]]
rely on that empirical evidence to predict future impacts, such as
increased stream temperatures (see status review for Rio Grande
cutthroat trout, 73 FR 27900; May 14, 2008) or loss of sea ice (see
determination of threatened status for the polar bear, 73 FR 28212; May
15, 2008), and treat these effects as a threat that can be analyzed. In
instances for which a direct cause and effect relationship between
global climate change and regional effects to a specific species has
not been documented, we rely primarily on synthesis documents (e.g.,
IPCC 2007, entire; Independent Scientific Advisory Board 2007, entire;
Karl et al. 2009, entire) to inform our evaluation of the extent that
regional impacts due to climate change may affect our species. These
synthesis documents present the consensus view of climate change
experts from around the world. Additionally, we have examined models
downscaled to specific regions (e.g., Ray et al. 2010, entire; WRCC
2011, p. 1; CIG 2011, p. 1)--including some in-progress finer-scaled
models that include Wyoming and the surrounding area--in order to
inform our evaluation of the extent that regional impacts may threaten
species. Typically, the projections of downscaled models agree with the
projections of the global climate models (Ray et al. 2010, p. 25).
Climate change projections are based on models with assumptions and are
not absolute.
Portions of the global climate change models can be used to predict
changes at the regional-landscape scale; however, this approach
contains higher levels of uncertainty than using global models to
examine changes on a larger scale. The uncertainty arises due to
various factors related to difficulty in applying data to a smaller
scale, and to the paucity of information in these models such as
regional weather patterns, local physiographic conditions, life stages
of individual species, generation time of species, and species
reactions to changing carbon dioxide levels. Additionally, global
climate models do not incorporate a variety of plant-related factors
that could be informative in determining how climate change could
affect plant species (e.g., effect of elevated carbon dioxide on plant
water-use efficiency, the physiological effect to the species of
exceeding the assumed (modeled) bioclimatic limit, the life stage at
which the limit affects the species (seedling versus adult), the life
span of the species, and the movement of other organisms into the
species' range) (Shafer et al. 2001, p. 207). Moreover, empirical
studies are needed on what determines the distributions of species and
species assemblages.
Regional landscapes also can be examined by downscaling global
climate models. Two common methods of downscaling are statistical
downscaling and dynamic downscaling (Fowler et al. 2007, p. 1548).
These downscaled models typically inherit the broad-scale results of
global climate change models, imbed additional information, and run the
models at a finer scale (Ray et al. 2010, p. 25, Hostetler 2011, pers.
comm.). These methods provide additional information at a finer spatial
scale (i.e., all of Wyoming downscaled to a 15-km (9.3-mi) resolution
(Hostetler 2010, pers. comm.). However, they are not able to account
for the myriad of processes that may affect a species that only
inhabits a narrow range, as local effects may reduce or amplify the
large-scale patterns that are projected over the larger spatial
resolution of the global climate models (Ray et al. 2010, p. 24). In
summary, global climate models can play an important role in
characterizing the types of changes that may occur, so that the
potential impacts on natural systems can be assessed (Shafer et al.
2001, p. 213). However, they are of limited use to assess local impacts
to species with a limited range, such as the five plants discussed in
this finding.
Climate change is likely to affect the habitat of Abronia
ammophila, but we lack scientific information on what those changes may
ultimately mean for the status of the species. Yellowstone Lake water
levels affect habitat conditions for A. ammophila. As noted previously,
the record high lake levels of 1996 and 1997 (due to increased snowpack
and subsequent spring snowmelt) had both positive and negative effects
on A. ammophila (NPS 1999b, p. 7; Whipple 2002, p. 265). In general,
the outflow and maximum water surface elevation of Yellowstone Lake are
functions of winter snow accumulation and spring precipitation inputs;
these vary significantly from year to year (Farnes 2002, p. 73).
Analysis of snow depth and last date of snow cover in YNP from 1948 to
2003 has shown that winters are getting shorter, as measured by the
number of days with snow on the ground (Wilmers and Getz 2005, entire).
This change is due to decreased snowfall and an increase in the number
of days with temperatures above freezing (Wilmers and Getz 2005,
entire).
Climate change effects are not limited to the timing and amount of
precipitation; other factors potentially influenced by climate change
may in turn affect the habitat conditions for Abronia ammophila. For
example, fire frequency, insect populations (e.g., mountain pine
beetle, Dendroctonus ponderosae), and forest pathogens may be
influenced by climate change (Logan and Powell 2001, p. 170; Westerling
et al. 2006, pp. 942-943) and may in turn affect forest canopy cover
and the timing of snowmelt within the Yellowstone Lake watershed. The
increased rate of snowmelt caused by fire-generated openings in the
forest canopy from the 1988 fires in YNP may have slightly reduced the
annual maximum Yellowstone Lake level because it spread the snowpack
melt rate over a longer period of time (Farnes 2002, p. 73). Impacts of
specific events on A. ammophila and its habitat have not been analyzed.
Climate change is likely to affect multiple variables that may
influence the availability of habitat for A. ammophila. As lake levels
have fluctuated in the past and A. ammophila has adapted to these
fluctuations, this species should be able to persist so long as climate
change does not result in extreme changes to important characteristics
of the species habitat, such as the complete loss of water from
Yellowstone Lake. At this time, the best available scientific
information does not indicate that impacts from climate change are
likely to threaten the species now or in the foreseeable future.
Drought
Precipitation studies show that YNP weather cycles typically follow
the larger weather patterns across the larger Northern Rockies
ecosystem (Gray et al. 2007, p. 24). The reconstruction of
precipitation levels in YNP from AD 1173-1998 shows strong interannual
variability (Gray et al. 2007, entire). Moreover, extreme wet and dry
years, which have occurred recently, fall within the range of past
variability (Gray et al. 2007, entire).
We believe that Abronia ammophila has evolved to adapt to recurring
drought conditions because it persists in this type of environment.
Short-term population fluctuations appear to be typical for the
species. The population at Rock Point was thought to have been
extirpated due to drought; however, a survey in 2004 located seedlings
at this site (Saunders and Sipes 2004, p. 4). The Pumice Point
population completely vanishes some years. It is located on sand that
does not connect to the aquifer, and during drought years the
population can be 9.1 m (30 ft) above water (Whipple 2010e, pers.
comm.). Although drought may temporarily influence the abundance of
[[Page 33932]]
plants at some specific locations, we have no information indicating
that drought threatens the species now or in the foreseeable future.
Summary of Factor A
YNP offers protection of Abronia ammophila populations from all
kinds of development including roads, campgrounds, buildings, mining,
and energy development. There are currently no plans for any further
development in YNP near the existing populations or potential habitat
of A. ammophila. We have no information to suggest that trampling,
nonnative invasive plants, climate change, or drought represents a
threat to the species.
We conclude that the best scientific and commercial information
available indicates that Abronia ammophila is not in danger of
extinction or likely to become so within the foreseeable future because
of the present or threatened destruction, modification, or curtailment
of its habitat or range.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
There has been limited use and collection of Abronia ammophila and
its parts for scientific study (Saunders and Sipes 2006, p. 77).
Additionally, the Denver Botanical Gardens (DBG) collected
approximately 3,300 A. ammophila seeds in 2005 (DBG 2008, p. 3). The
DBG is a participating institution in the Center for Plant
Conservation, an organization dedicated to preventing the extinction of
plants native to the United States (Center for Plant Conservation 2010,
unpaginated). Because these collections were limited, we do not believe
this collection constituted a threat to the species. The collections
also contribute to the long-term conservation of the species.
Specimens, seeds, and parts of Abronia ammophila are occasionally
collected for scientific purposes in order to increase the knowledge of
this species (e.g., Saunders and Sipes 2006; DBG 2008); however, these
collections are rare. We do not have any evidence of risks to A.
ammophila from overutilization for commercial, recreational,
scientific, or educational purposes, and we have no reason to believe
this factor will become a threat to the species in the future. We
conclude that the best scientific and commercial information available
indicates that A. ammophila is not in danger of extinction or likely to
become so within the foreseeable future because of overutilization for
commercial, recreational, scientific, or educational purposes.
Factor C. Disease or Predation
Disease
Abronia ammophila is not known to be affected or threatened by any
disease. Therefore, we do not consider disease to be a threat to A.
ammophila now or in the foreseeable future.
Predation--Grazing and Herbivory
No studies have been conducted investigating the effects of grazing
or herbivory on Abronia ammophila. Minimal insect herbivory has been
noted. Sphingid moth larvae and others tentatively identified in the
family Noctuidae have been seen feeding on the aboveground plant parts
(Saunders and Sipes 2004, p. 11). Also, what appeared to be an army
cutworm caterpillar was observed eating the belowground parts of an
uprooted plant (NPS 1999b, p. 7).
Additionally, some uprooted, partially eaten taproots were found in
areas with abundant rodent tunnels (NPS 1999b, p. 7). Ungulate grazing
has been noted on species that grow near Abronia ammophila; however,
none has been noted on A. ammophila (NPS 1999b, p. 7). Any predation,
as noted above, would represent a natural ecological interaction in
YNP. We have no evidence that the extent of such predation represents a
population level threat to A. ammophila. Therefore, we do not consider
predation to be a threat to the species now or in the foreseeable
future.
Summary of Factor C
We have no evidence of adverse impacts to Abronia ammophila from
disease or predation. We conclude that the best scientific and
commercial information available indicates that A. ammophila is not in
danger of extinction or likely to become so within the foreseeable
future because of disease or predation from herbivory or grazing.
Factor D. The Inadequacy of Existing Regulatory Mechanisms
The Act requires us to examine the adequacy of existing regulatory
mechanisms with respect to threats that may place Abronia ammophila in
danger of extinction or likely to become so in the future. Existing
regulatory mechanisms that could have an effect on potential threats to
A. ammophila include (1) local land use laws, processes, and
ordinances; (2) State laws and regulations; and (3) Federal laws and
regulations. A. ammophila occurs entirely on Federal land under the
jurisdiction of the YNP; therefore, the discussion below focuses on
Federal laws. Actions adopted by local groups, States, or Federal
entities that are discretionary, including conservation strategies and
guidance, are not regulatory mechanisms; however, we may discuss them
in relation to their effects on potential threats to the species.
Federal Laws and Regulations
Yellowstone National Park
All known populations of Abronia ammophila occur within YNP. The
YNP was established as the first national park on March 1, 1872, under
control of the Secretary of the Department of the Interior (NPS 2010c,
unpaginated). The NPS was established by the NPS Organic Act of 1916,
and reaffirmed by the General Authorities Act, as amended (NPS 2008a,
unpaginated; Schneider 2010, pers. comm.). The NPS Organic Act states,
``[The NPS] shall promote and regulate the use of the Federal areas
known as national parks, monuments, and reservations* * * to conserve
the scenery and the natural and historic objects and the wild life
therein and to provide for the enjoyment of the same in such manner and
by such means as will leave them unimpaired for the enjoyment of future
generations'' (16 USC 1) (NPS 2006b, p. 8; NPS 2008a, unpaginated;
Schneider 2010, pers. comm.).
Additionally, the Management Policies of the NPS state that
conservation is paramount in situations of conflict between conserving
resources and values and providing for enjoyment of them (NPS 2006b, p.
9; Schneider 2010, pers. comm.). These policies also charge the NPS
with preserving the fundamental physical and biological processes, and
maintaining all the components and processes of a naturally evolving
park ecosystem, including the natural abundance, diversity, and genetic
and ecological integrity of the plant and animal species native to
those ecosystems (NPS 2006b, pp. 35-36; Schneider 2010, pers. comm.).
The NPS is responsible for the inventory of native species that are of
special management concern to parks (such as rare, declining,
sensitive, or unique species and their habitats) and will manage them
to maintain their natural distribution and abundance (NPS 2006b, pp.
45-46; Schneider 2010, pers. comm.). The Management Policies also
direct the NPS to control detrimental nonnative species and manage
detrimental visitor access (NPS 2006, p. 45).
As stated above, YNP is required, to the maximum extent
practicable, to
[[Page 33933]]
prevent exotic (nonnative invasive) plant introduction and to control
established exotic plants by law, executive order, and management
policy (e.g., Executive Order 13112, National Park Service Management
Policies (NPS 1988), and the Federal Noxious Weed Act of 1974) (Olliff
et al. 2001, pp. 348-349). YNP's approach emphasizes prevention,
education, early detection and eradication, control, and monitoring
(Olliff et al. 2001, entire).
Visitors to national parks are prohibited from removing, defacing,
or destroying any plant, animal, or mineral; this includes collecting
natural or archeological objects (NPS 2006c, p. 2). Visitors are
prohibited from driving off roadways or camping outside of designated
campgrounds (NPS 2010d, unpaginated). Additionally, YNP has developed a
Conservation Plan for Abronia ammophila (NPS 1999b, entire). This plan
recommends the protection of all known (and any newly discovered)
populations, monitoring of the populations, reestablishment of
historical occupancy areas, long-term seed storage, and research (NPS
1999b, pp. 10-11).
National Environmental Policy Act
All Federal agencies are required to adhere to the National
Environmental Policy Act (NEPA) of 1970 (42 U.S.C. 4321 et seq.) for
projects they fund, authorize, or carry out. The Council on
Environmental Quality's regulations for implementing NEPA (40 CFR 1500-
1518) state that agencies shall include a discussion on the
environmental impacts of the various project alternatives, any adverse
environmental effects which cannot be avoided, and any irreversible or
irretrievable commitments of resources involved (40 CFR 1502).
Additionally, activities on non-Federal lands are subject to NEPA if
there is a Federal nexus. The NEPA is a disclosure law, and does not
require subsequent minimization or mitigation measures by the Federal
agency involved. Although Federal agencies may include conservation
measures for sensitive species as a result of the NEPA process, any
such measures are typically voluntary in nature and are not required by
the statute.
Summary of Factor D
We considered the adequacy of existing regulatory mechanisms to
protect Abronia ammophila. We believe the existing regulatory
mechanisms, especially the NPS Organic Act, adequately protect the
Yellowstone Lake shore habitat of Abronia ammophila from the potential
threats of development, trampling, and nonnative invasive plants. We
expect that A. ammophila and its habitat will be generally protected
from direct human disturbance. Therefore, we conclude that the existing
regulatory mechanisms are adequate to protect A. ammophila from the
known potential threat factors.
We conclude that the best scientific and commercial information
available indicates that Abronia ammophila is not in danger of
extinction or likely to become so within the foreseeable future because
of inadequate regulatory mechanisms.
Factor E. Other Natural or Manmade Factors Affecting Its Continued
Existence
Natural and manmade factors with the potential to affect Abronia
ammophila include: (1) Small population size, (2) pollination, and (3)
genetic diversity.
Small Population Size
Small populations can be especially vulnerable to environmental
disturbances such as habitat loss, nonnative species, grazing, and
climate change (Barrett and Kohn 1991, p. 7; Oostermeijer 2003, p. 21;
O'Grady 2004, pp. 513-514). However, plants that are historically rare
may have certain adaptations to rarity (e.g., early blooming, extended
flowering, or mixed-mating systems) that enable them to persist
(Brigham 2003, p. 61).
Based on herbarium records, extirpation of Abronia ammophila sites
has occurred (see Distribution and Abundance discussion above).
However, additional sites also have been recently discovered, and not
all suitable habitat within YNP has been surveyed (NPS 1999a, pp. 6-7).
We have no information on whether these new sites represent recent
expansion of the species or if surveys were not previously conducted in
these areas.
We do not have any indication that Abronia ammophila was ever
present on the landscape over a more extensive range. Existing sites
are monitored, and surveys have located new occurrences. We have no
information indicating that random demographic or environmental events
are a threat to the species now or in the foreseeable future because of
its small population size.
Pollination
Small populations may represent an unreliable food source, which
may be visited by fewer pollinators than larger, less fragmented
populations (Oostermeijer 2003, p. 23). However, low visitation rates
may be more of a concern in currently rare species that were
historically abundant (Brigham 2003, p. 84). We have no information
suggesting that Abronia ammophila was previously more abundant across
the landscape. Co-flowering species (species that flower during the
same timeframe) also may be important to pollination of A. ammophila;
the pollinators recorded as visiting A. ammophila also were observed
visiting other dune plants in the vicinity (Saunders and Sipes 2004, p.
13).
Only very limited information is available regarding pollination of
Abronia ammophila. However, A. ammophila is a historically rare species
that exhibits a mixed-mating system. A mixed-mating system and co-
flowering species may help alleviate negative effects that may occur
due to low pollination visitation rates. Therefore, we have no
information indicating that poor pollination is a threat to the species
now or in the foreseeable future.
Genetic Diversity
Small population size can decrease genetic diversity due to genetic
drift (the random change in genetic variation each generation), and
inbreeding (mating of related individuals) (Antonovics 1976, p. 238;
Ellstram and Elam 1993, pp. 218-219). Genetic drift can decrease
genetic variation within a population by favoring certain
characteristics and, thereby, increasing differences between
populations (Ellstram and Elam 1993, pp. 218-219). Self-fertilization
and low dispersal rates can cause low genetic diversity due to
inbreeding (Antonovics 1976, p. 238; Barrett and Kohn 1991, p. 21).
This decreased genetic diversity diminishes a species' ability to adapt
to the selective pressures of a changing environment (Newman and Pilson
1997, p. 360; Ellstrand 1992, p. 77).
Limited information is available regarding the genetic diversity of
the Abronia genus. No information is available regarding the genetic
diversity exhibited by Abronia ammophila. Therefore, we have no
information indicating that a lack of genetic diversity is a threat to
the species now or in the foreseeable future.
Summary of Factor E
Abronia ammophila is a historically rare species that, as such, has
adaptations such as a mixed-mating system and prolific flowering, which
minimize the risks of small population size, low pollinator abundance,
and genetic diversity. Therefore, we conclude that the best scientific
and commercial information available indicates that Abronia ammophila
is not in danger of extinction or likely to become so within the
foreseeable future because of small population size,
[[Page 33934]]
pollination, or reduced genetic diversity.
Finding for Abronia ammophila
As required by the Act, we considered the five factors in assessing
whether Abronia ammophila is threatened or endangered throughout all of
its range. We examined the best scientific and commercial information
available regarding the past, present, and future threats faced by A.
ammophila. We reviewed the petition, information available in our
files, other available published and unpublished information, and we
consulted with recognized A. ammophila experts and other Federal and
State agencies.
The primary factor potentially impacting Abronia ammophila is human
disturbance through trampling. However, studies that have sought to
quantify foot traffic in the habitat of A. ammophila have found that
there is little foot traffic occurring (NPS 1999a, pp. 2, 5).
Additionally, A. ammophila prefers open sites and thrives under some
disturbance. Other factors potentially affecting A. ammophila--
including nonnative invasive plants, drought, small population size,
limited pollinators, and genetic diversity--are either limited in
scope, or lacking evidence apparent to us indicating that they
adversely impact the species. We have no evidence that overutilization,
disease, or predation are affecting this species. Although climate
change will likely impact the status of some plant species in the
future, we do not have enough information to determine that climate
change will result in a species-level response from A. ammophila.
Additionally, the existing regulatory mechanisms directing management
of YNP appear to be adequate to protect the species from potential
threats.
Based on our review of the best available scientific and commercial
information pertaining to the five factors, we find that the threats
are not of sufficient imminence, intensity, or magnitude to indicate
that Abronia ammophila is in danger of extinction (endangered) or
likely to become endangered within the foreseeable future (threatened),
throughout all of its range. Therefore, we find that listing A.
ammophila as a threatened or endangered species is not warranted
throughout its range.
Significant Portion of the Range
Having determined that Abronia ammophila does not meet the
definition of a threatened or endangered species, we must next consider
whether there are any significant portions of the range where A.
ammophila is in danger of extinction or is likely to become endangered
in the foreseeable future.
In determining whether Abronia ammophila is threatened or
endangered in a significant portion of its range, we first addressed
whether any portions of the range of A. ammophila warrant further
consideration. We evaluated the current range of A. ammophila to
determine if there is any apparent geographic concentration of the
primary stressors potentially affecting the species including
trampling, nonnative invasive plants, drought, small population size,
limited pollinators, and genetic diversity. This species' small range
suggests that stressors are likely to affect it in a uniform manner
throughout its range. However, we found the stressors are not of
sufficient imminence, intensity, magnitude, or geographically
concentrated such that it warrants evaluating whether a portion of the
range is significant under the Act. We do not find that A. ammophila is
in danger of extinction now, nor is likely to become endangered within
the foreseeable future, throughout all or a significant portion of its
range. Therefore, listing A. ammophila as threatened or endangered
under the Act is not warranted at this time.
We request that you submit any new information concerning the
status of, or threats to, Abronia ammophila to our Wyoming Ecological
Services Field Office (see ADDRESSES section) whenever it becomes
available. New information will help us monitor A. ammophila and
encourage its conservation. If an emergency situation develops for A.
ammophila, or any other species, we will act to provide immediate
protection.
Species Information for Agrostis rossiae
Species Description
Agrostis rossiae is a small annual grass in the family Poaceae
(Clark et al. 1989, p. 8; Fertig 1994, unpaginated; 2000c,
unpaginated). A. rossiae grows as a dense clump about 5 to 15 cm (2.0
to 5.9 in.) high (Fertig 2000c, unpaginated). The short leaves are 1.0
to 2.5 cm (0.39 to 0.98 in.) long, and 0.5 to 2.0 millimeters (mm)
(0.02 to 0.08 in.) wide, with slightly inflated and smooth sheaths (the
lower part of the leaf that surrounds the stem) (Clark et al. 1989, p.
8; Clark and Dorn 1981, p. 10; Fertig 1994, unpaginated; 2000c,
unpaginated). The one-flowered spikelets (flowers) form at the top of
the stems in a narrow, compact panicle (a structure in which the
flowers mature from the bottom upwards) that is 2.0 to 6.0 cm (0.79 to
2.36 in.) long (Dorn 1980, p. 59; Fertig 2000c, unpaginated). The
panicle remains compact at maturity (Fertig 1994, unpaginated).
Branches of the panicle are scabrous (rough), purple, and lack
spikelets at the base (Clark et al. 1989, p. 8; Dorn 1980, p. 59;
Fertig 2000c, unpaginated).
Discovery and Taxonomy
Edith A. Ross collected the first recorded specimen of Agrostis
rossiae in July of 1890 (Vasey 1982, p. 77; Hitchcock 1905, p. 41). The
genus Agrostis consists of over 100 species occurring in both
hemispheres, typically in cooler areas of temperate climates (Hitchcock
1905, p. 5). More recent sources list 150 to 200 species (Harvey 2007,
unpaginated), or up to 220 species within the Agrostis genus (Watson
and Dallwitz 1992, unpaginated).
Species of the Agrostis genus are able to form morphologically
similar ecotypes (subspecies that survives as a distinct group due to
environmental pressures and isolation) in response to variations in
climate, heavy metals in the soil, and other unusual soil conditions
(Bradshaw 1959, entire; Jowett 1964, p. 78; Aston and Bradshaw 1966,
entire; Jain and Bradshaw 1966, pp. 415-417). Therefore, morphology of
Agrostis species is not a reliable indicator of species (Tercek 2003,
p. 9).
In the geothermally influenced areas of YNP, thermal Agrostis
scabra (rough bentgrass) is sympatric (occurs in the same area) with
Agrostis rossiae (Tercek 2003, pp. 9-10). A. scabra occurs as an annual
in the thermal areas of YNP; however, this species is typically a
perennial when it occurs in nonthermal habitats (Fertig 2000c,
unpaginated; Tercek 2003, pp. 9-10). A. scabra can be distinguished
from A. rossiae, when mature, by its spreading panicle (Fertig 1994,
unpaginated; 2000c, unpaginated; Tercek 2003, pp. 9-10). Another
similar species, although not sympatric, is Agrostis variabilis
(mountain bentgrass), which is a perennial with panicle branches
bearing spikelets nearly to the base (whereas A. rossiae lacks
spikelets at the base) (Fertig 1994, unpaginated; Fertig 2000c,
unpaginated). Genetic studies have shown that thermal Agrostis species
occurring in YNP are more closely related to other thermal Agrostis
species worldwide than to the nonthermal Agrostis scabra (Tercek 2003,
pp. 17-21). Additionally, A. rossiae and thermal A. scabra are closely
related to each other (Tercek et al. 2003, p. 1308-1309); however,
additional genetic studies need to be completed to quantify their
relationship. We recognize A. rossiae as a valid species and a listable
entity.
[[Page 33935]]
Biology and Life History
Agrostis rossiae is a thermal species that takes advantage of the
warmth from its environment and germinates from December to January,
when nonthermal areas remain covered in snow (Tercek 2003, pp. 12, 45,
51). The growing season for A. rossiae is from December 1 to April 1;
it blooms in May, matures in June, and dies by mid-June when the
thermal ground temperature reaches between 40 and 45 [deg]C (104 and
113 [deg]F) (a temperature that kills A. rossiae) (Beetle 1977, p. 40;
Tercek 2003, pp. 10, 34, 12, 45, 51-52).
Agrostis rossiae plants do not have a reduced seed set when
isolated from external pollen sources; this suggests that A. rossiae
reproduces through apomixis (reproduction that does not involve
pollination) (Tercek 2003, p. 19). Seeds remain viable for about 100
years in artificial conditions, but persist for less time in natural
conditions (Tercek 2010, pers. comm.). Seeds do not disperse very far
from the parent plant (Whipple 2010a, pers. comm.).
Habitat
Typically, Agrostis rossiae grows on glacial deposits, which are at
a slightly higher elevation than nearby hot springs (Tercek 2003, p.
11). These deposits border active geysers and hot springs at elevations
of 2,210 to 2,256 m (7,250 to 7,400 ft) (Clark et al. 1989, p. 8;
Fertig 1994, unpaginated; 2000c, unpaginated). These geothermally
influenced soils remain moist throughout the year even though they are
partially isolated from the water table of nearby hot springs by the
higher elevation or a nonpermeable rock layer (White et al. 1971, p.
77; Fournier 1989, pp. 20-21; Tercek 2003, pp. 36, 45-46; Tercek and
Whitbeck 2004, p. 1956).
The geysers in YNP are vapor-dominated, meaning that steam and
other gases rise out of the ground (Fournier 1989, pp. 20-21; Tercek
2003, p. 36). The geysers are important to the soils because the
elements and chemicals produced from the geysers affect the composition
of the soil on which this species grows. The accompanying soils are
rich in silica and calcium, and contain gases such as hydrogen sulfide
and iron sulfide that are converted into sulfuric acid by bacteria
(Tercek and Whitbeck 2004, p. 1956; White et al. 1971, p. 77; Fournier
1989, pp. 20-21; Tercek 2003, p. 36). The sulfuric acid lowers the pH
(a measure of acidity and alkalinity) of the soil (White et al. 1971,
p. 77; Fournier 1989, pp. 20-21; Tercek 2003, p. 36). YNP's thermal
soils are more acidic (pH 3.9-5.6), in general, than the nonthermal
soils (pH 4.3-6.4) (Tercek and Whitbeck 2004, p. 1964). Agrostis
rossiae demonstrates peak growth in acidic soils (pH 3.0), whereas the
optimal growth of both thermal and nonthermal Agrostis scabra occurs at
a pH of 5.0 (Terceck and Whitbeck 2004, p. 1964). While A. rossiae is
more tolerant of acidity than other sympatric Agrostis species, its
growth declines at pH of less than 3.0 (Tercek and Whitbeck 2004, p.
1964). Many of the thermal features in YNP have a very high acidity
(Whipple 2011, pers. comm.).
In addition to Agrostis scabra, a limited number of thermally
adapted species occur in the same habitat as Agrostis rossiae:
Racomitrium canescens (Racomitrium moss), several heat-loving soil
fungi, a heat-tolerant grass--Dichanthelium lanuginosum (panicgrass),
and a few annual forbs (Tercek and Whitbeck 2004, p. 1956). Annual
forbs include Conyza canadensis (Canadian horseweed), Gnaphalium
stramineum (cottonbatting plant), Plantago elongata (Prairie plantain),
Mimulus guttatus (seep monkeyflower), and Heterotheca depressa (hairy
false goldenaster) (Fertig 2000c, unpaginated).
Distribution and Abundance
Agrostis rossiae is endemic to YNP, occurring only in Teton County,
Wyoming (Beetle 1977, p. 40; Clark and Dorn 1981, p. 10; Clark et al.
1989, p. 8; Fertig 2000c, unpaginated, Tercek 2003, p. 10). Even though
there are many thermal areas in YNP, Agrostis rossiae only occurs in
the west-central portion of YNP (Tercek 2003, p. 10). Specifically, A.
rossiae only occurs in the Firehole River drainage and the Shoshone
Geyser Basin (Greater Yellowstone 2010, unpaginated). The reason for
this restriction is not known. One proposed hypothesis is that the high
acidity of some of the other thermal areas restricts the species'
distribution; another is that A. rossiae is a fairly recently evolved
species that has not had time for successive generations to disperse
and colonize a wider area (Whipple 2010e, pers. comm.).
Four known populations of the plant occur in an area of
approximately 4.86 ha (12 ac); these populations are named Upper Geyser
Basin, Shoshone, Midway, and Lower Geyser (Whipple 2010a, pers. comm.).
Many of these occurrences are ephemeral (only persist for a short
period) subpopulations (Fertig 2000c, unpaginated). Because of the
changing thermal habitat, subpopulation numbers and locations may
fluctuate greatly (Fertig 2000c, unpaginated). One small (generally
less than 50 plants) subpopulation northeast of Infant Geyser in Geyser
Hill disappeared due to changes in soil temperatures between 1992 and
2008 (Fertig 2000c, unpaginated; Whipple 2010e, pers. comm.).
The WNDD has designated Agrostis rossiae as a plant species of
concern with ranks of G1 and S1 (Heidel 2007, p. 1). This designation
indicates that A. rossiae is considered to be critically imperiled
because of extreme rarity. For background information on G1 and S1
rankings, please refer to the last paragraph under Distribution and
Abundance in the Species Information for Abronia ammophila section.
Since A. rossiae is endemic to Wyoming, the Wyoming occurrences
encompass the entire global range. Additionally, YNP considers A.
rossiae to be a sensitive species of concern; therefore, it evaluates
effects to this species in conjunction with any project or action that
has the potential to affect the plant (Whipple 2011, pers. comm.).
Trends
Subpopulations can range in size from a solitary plant up to
several thousand plants, in an area with a diameter of 100 m (328.1 ft)
(Tercek 2003, p. 10; Tercek and Whitbeck 2004, p. 1956). Surveys
conducted in 1995 suggest that the total population of all known
Agrostis rossiae plants is approximately 5,000 to 7,500 individuals
(Fertig 2000a, p. 36; 2000a, unpaginated). The 1998 survey determined
the total population consisted of between 5,580 and 7,735 plants
(Whipple in litt. 2009, entire). The entire population has not been
surveyed in any additional years (Whipple in litt. 2009, entire).
Surveys have been completed on a sporadic schedule, with not all
populations surveyed in a given year (Whipple 2009 in litt.,
unpaginated). All population counts are estimates as A. rossiae is an
annual with a clumped growth form, and exact counts are unable to be
obtained without destroying the plants (Whipple 2010d, pers. comm.).
Overall, there is not enough information to conclusively determine
rangewide trends; however, the total population numbers appear to be
stable despite subpopulation fluctuations. Additionally, the known
populations have expanded in the last 3 years (Whipple 2010a, pers.
comm.).
Five Factor Evaluation for Agrostis rossiae
Information pertaining to Agrostis rossiae in relation to the five
factors provided in section 4(a)(1) of the Act is discussed below.
[[Page 33936]]
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
The following potential factors that may affect the habitat or
range of Agrostis rossiae are discussed in this section, including: (1)
Development, (2) trampling, (3) nonnative invasive species, (4) climate
change, (5) thermal fluctuations, (6) drought, and (7) fire.
Development
Agrostis rossiae occurs entirely inside YNP, which limits potential
threats to its habitat from development. As stated above (see Factor D
under Abronia ammophila), YNP owns both its land and the mineral rights
so energy development within the YNP's boundary is not a threat (Mazzu
2010, pers. comm.; Whipple 2010e, pers. comm.).
In the late 1970s and early 1980s, potential for geothermal energy
development outside YNP was considered a threat to Agrostis rossiae
because of the potential to affect the thermal basin that underlies YNP
(Fertig 2000, unpaginated). Currently, no known applications for
geothermal leases have this potential (Mazzu 2010, pers. comm.; Whipple
2010e, pers. comm.). However, applications are occasionally made for
geothermal leases in the geothermal areas outside of YNP (NPS 2008b,
unpaginated). The Geothermal Steam Act of 1970 (30 U.S.C. 1001-1027,
December 24, 1970), as amended in 1977, 1988, and 1993, provides
protections for the thermal features in YNP (see Factor D. The
Inadequacy of Existing Regulatory Mechanisms below) (Legal Information
Institute 2010, unpaginated). This law should protect the species,
unless high energy costs, such as occurred in the late 1970s and early
1980s, encourage development interest that results in changes that
weaken these protections. Therefore, A. rossiae is not threatened by
geothermal energy development inside or outside of YNP's boundary.
As stated above, new construction of roads, trails, or structures
occurring in YNP is rare, with reconstruction of existing features
occurring occasionally (Whipple 2010e, pers. comm.). When new
construction or reconstruction occurs in areas where there are
sensitive species, YNP analyzes and carries out construction in a
manner that minimizes adverse effects. For example, the reconstruction
of the Biscuit Basin Boardwalk in the summer of 2010 included rerouting
the boardwalk and restoration of Agrostis rossiae habitat that had been
impacted during prior maintenance (Whipple 2010a, pers. comm.; 2010e,
pers. comm.).
The majority of YNP remains undeveloped, and we have no information
that this will change; therefore, we do not view development to be a
threat to the species now or in the foreseeable future.
Trampling
Most habitat of Agrostis rossiae is easily accessible to visitors,
as it is generally located near popular thermal features in YNP
(Whipple 2010a, pers. comm.). However, visitors are required to stay on
boardwalks and designated trails around thermal areas (NPS 2006c,
unpaginated). Human impact to A. rossiae was noted in a survey of the
Shoshone Geyser Basin area (Whipple 2009 in litt., unpaginated). This
trampling was partially mitigated by the reroute discussed above;
surveys in 2000, after the trail was rerouted, documented a healthy A.
rossiae population (Whipple 2009 in litt., unpaginated). No studies
have specifically examined disturbance due to trampling or its effects
on A. rossiae. However, A. rossiae is typically located in the vicinity
of thermal features that could be detrimental for humans to walk near,
and any areas that have the potential for trampling are protected by
YNP's policies.
For information on impacts of increased visitation to YNP, please
refer to the ``Trampling'' discussion under Factor A. The Present or
Threatened Destruction, Modification, or Curtailment of Its Habitat or
Range in the Five Factor Evaluation for Abronia ammophila section. As
the plant is located in YNP, it is afforded protections (see Factor D:
The Inadequacy of Existing Regulatory Mechanisms below).
Wildlife, also, have the potential to trample Agrostis rossiae.
American bison (Bison bison) scat (fecal droppings) has been found in
the vicinity of A. rossiae at several sites; however, no trampling of
A. rossiae was noted in the survey notes (Whipple 2009 in litt.,
unpaginated). In 1998, a small patch of A. rossiae was highly impacted
by the actions of a rutting bull elk (Cervus canadensis); however, that
A. rossiae population was reported to be healthy when resurveyed in
2000 (Whipple 2009 in litt., unpaginated). We believe that these
anecdotal observations do not add up to routine impacts on a scale that
would cause the species to be threatened or endangered. Additionally,
we believe that trampling by wildlife, as noted above, represents a
natural ecological interaction in YNP with which the species would have
evolved and poses no threat to long-term persistence.
We have no information indicating that trampling by either humans
or wildlife is a threat to the species now or in the foreseeable
future.
Nonnative Invasive Plants
For general background information on nonnative invasive plants,
please refer to the first paragraph of ``Nonnative Invasive Plants''
under Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range in the Five Factor Evaluation for
Abronia ammophila section.
As stated above, as of 2010, YNP has documented 218 nonnative plant
species occurring within its boundaries (NPS 2010e, p. 1). The majority
of these plants have not been documented in or around Agrostis rossiae
habitat. Encroachment of nonnative species has the potential to affect
Agrostis rossiae. However, at this time, none of the nonnative species
are able to tolerate the hottest of the thermal habitats, where A.
rossiae primarily grows (Whipple 2010e, pers. comm.). Several nonnative
species that are considered either invasive or exotic occur near the
thermal habitats of A. rossiae (Whipple 2009 in litt., entire). In
order to combat nonnative invasives that can tolerate the transition
areas closer to the thermal habitat of A. rossiae, YNP is targeting
Rumex acetosella (common sheep sorrel) around the Shoshone Geyser Basin
(Schneider 2010 pers. comm.) and Hypericum perforatum (St. John's wort)
near the Lower Geyser Basin (Whipple 2010f, pers. comm.). Additionally,
NPS plans to establish trial plots in some of the geyser basins to
determine the best control mechanisms (Schneider 2010 pers. comm.).
Nonnative species currently occur only within the transition zones and
not in the hot thermal habitat of A. rossiae. Additionally, the NPS has
an exotic plant management plan (see Factor D: The Inadequacy of
Existing Regulatory Mechanisms in the Five Factor Evaluation for
Abronia ammophila section), which includes measures to identify and
treat any new nonnatives; therefore, we believe that A. rossiae will be
protected from nonnative plant invasions.
We have no information indicating that nonnative invasive species
are modifying the habitat of Agrostis rossiae to the extent that they
represent a threat to the species now or in the foreseeable future.
[[Page 33937]]
Climate Change
For general background information on climate change, please refer
to the first paragraphs of ``Climate Change'' under Factor A. The
Present or Threatened Destruction, Modification, or Curtailment of Its
Habitat or Range in the Five Factor Evaluation for Abronia ammophila
section.
Agrostis rossiae is adapted to an ephemeral habitat subject to
lethal summer soil temperatures and appears most clearly influenced by
the condition of thermal features as opposed to other climatic factors.
Although climate change has the potential to affect the species'
habitat, it is not clear that climate change has relevance to the
condition or availability of habitat for this species because we have
no information that climate change will play a significant role in
altering geothermal features. Climate change may affect the timing and
amount of precipitation as well as other factors linked to habitat
conditions for this species. We are uncertain how these changes will
affect the geothermal habitat of A. rossiae. At this time the available
scientific information does not clearly indicate that climate change is
likely to threaten the species now or in the foreseeable future.
Thermal Fluctuations
The thermal features in YNP are part of the largest and most varied
geyser basin in the world; this basin is essentially undisturbed (NPS
2008b, unpaginated). Few of YNP's thermal features have ever been
diverted for human use (such as bathing pools or energy), despite the
proximity of roads and trails (NPS 2008b, unpaginated). Thermal
features can be affected by nearby ground-disturbing activities; water,
sewer, and other utility systems adjacent to YNP have likely affected
the park's features in the past (NPS 2008b, unpaginated). In other
countries, geothermal drill holes and wells located 4.02 to 9.98 km
(2.5 to 6.2 mi) from thermal features have reduced geyser activity and
hot spring discharges (NPS 2008b, unpaginated). Connections between
YNP's underlying geothermal basins are not fully understood. Therefore,
if geothermal activities were to occur outside YNP, they could have the
potential to affect this species.
Agrostis rossiae tends to follow very subtle geothermal features,
growing along geothermal cracks and edges of sunken pools (Whipple
2010e, pers. comm.). For example, in Cathos Springs, A. rossiae
currently grows along one crack and in a ring around the spring;
however, when the water level is higher or the ground level hotter, the
distribution shifts, or the plant may not be present at all in a given
year (Whipple 2010e, pers. comm.). As discussed above, the Geothermal
Steam Act of 1970 (30 U.S.C. 1001-1027, December 24, 1970), as amended
in 1977, 1988, and 1993, prevents significant adverse effects to the
thermal features in YNP (see Factor D: The Inadequacy of Existing
Regulatory Mechanisms below) (Legal Information Institute 2010,
unpaginated). Additionally, the NPS is included in discussions of
activities that may affect the groundwater or geothermal areas of YNP
(Mazzu 2010, unpaginated). Therefore, we have no information indicating
that human-caused changes to the thermal features are likely to
threaten the species now or in the foreseeable future.
Drought
For background information, please refer to the first paragraph of
the ``Drought'' discussion under Factor A. The Present or Threatened
Destruction, Modification, or Curtailment of Its Habitat or Range in
the Five Factor Evaluation for Abronia ammophila section. As noted
above under the Habitat section for this species, the vapor-dominated
geothermally influenced soils on which Agrostis rossiae typically grows
remain moist throughout the year (Tercek 2003, pp. 36, 45-46). However,
these soils are influenced by the amount and timing of the rain that
falls in the area (Tercek and Whitbeck 2004, p. 1958). Typically around
May or June, the snow in the surrounding area has melted and rains are
no longer frequent enough for the soils in the areas surrounding the
habitat of A. rossiae to remain moist (Tercek and Whitbeck 2004, p.
1958). This decrease in soil moisture of the surrounding habitat is
accompanied by a sharp increase in the thermal soil temperatures
(Tercek and Whitbeck 2004, p. 1958). The typical growing season in the
hot thermal habitats is approximately 120 days (Tercek and Whitbeck
2004, p. 1963). A. rossiae requires only 30 to 70 days to complete its
life cycle (Tercek and Whitbeck 2004, p. 1963). A decrease in the
growing season of 40 percent could occur prior to drought having a
detrimental effect on this species. Prediction models indicate that
areas already affected by drought will suffer greater effects from
temperature increases caused by climate change and that high
precipitation effects will become more frequent (IPCC 2007, entire).
Although we do not fully understand how these changes will affect the
habitat of A. rossiae, we do know that this species is resilient to
changes in the thermal basins of its environment. Therefore, we do not
believe that drought will rise to the level of a threat to the species
now or in the foreseeable future.
Fire
As Agrostis rossiae completes its annual life cycle by mid-June, it
is typically dead by the time fire season occurs (Whipple 2010e, pers.
comm.); YNP's fire season generally extends from late June to the first
large rain events in September. The fires in 1988 burned the area where
A. rossiae occurs; however, the fire did not carry on the ground
through the A. rossiae populations and, therefore, did not have any
effect on the population (Whipple 2010e, pers. comm.). We have no
information indicating that fire is likely to threaten the species now
or in the foreseeable future.
Summary of Factor A
YNP offers protection to the populations of Agrostis rossiae from
all kinds of development, including roads, campgrounds, buildings,
mining, and energy development. There are currently no plans for any
further development in YNP near the existing populations or potential
habitat of A. rossiae. We have no information to show that Agrostis
rossiae is likely to be threatened by trampling, nonnative species,
climate change, thermal fluctuations, drought, or fire.
We conclude that the best scientific and commercial information
available indicates that Agrostis rossiae is not in danger of
extinction or likely to become so within the foreseeable future because
of the present or threatened destruction, modification, or curtailment
of its habitat or range.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
There has been limited use and collection of the leaves of Agrostis
rossiae for scientific purposes to determine the genetic relationship
between different Agrostis species (Tercek 2003, p. 12). We have no
indications of A. rossiae being collected for any other purposes
(Whipple 2010e, pers. comm.). Therefore, we conclude that the best
scientific and commercial information available indicates that A.
rossiae is not in danger of extinction or likely to become so within
the foreseeable future because of overutilization for commercial,
recreational, scientific, or educational purposes.
[[Page 33938]]
Factor C. Disease or Predation
Agrostis rossiae is not known to be affected or threatened by any
disease. We have no records showing predation by grazing or herbivory
on A. rossiae. Therefore, we conclude that the best scientific and
commercial information available indicates that A. rossiae is not in
danger of extinction or likely to become so within the foreseeable
future because of disease or predation.
Factor D. The Inadequacy of Existing Regulatory Mechanisms
All known populations of Agrostis rossiae occur within YNP, which
is under the jurisdiction of the NPS. Please refer to Yellowstone
National Park under the Factor D: The Inadequacy of Existing Regulatory
Mechanisms section in the Five Factor Evaluation for Abronia ammophila
section for additional information.
The Geothermal Steam Act of 1970 (30 U.S.C. 1001-1027, December 24,
1970), as amended in 1977, 1988, and 1993, governs the lease of
geothermal resources on public lands (Legal Information Institute 2010,
unpaginated). In addition to preventing the issuance of geothermal
leases on lands in YNP, it prevents the issuance of any lease that is
reasonably likely to result in a significant adverse effect on thermal
features within YNP (Legal Information Institute 2010, unpaginated).
Summary of Factor D
The existing regulatory mechanisms, especially the NPS Organic Act
and the Geothermal Steam Act, appear to adequately protect Agrostis
rossiae and its habitat in YNP. We expect that A. rossiae and its
habitat will be generally protected from direct human disturbance.
Therefore, we conclude that the existing regulatory mechanisms are
adequate to protect A. rossiae from the known potential threat factors.
We conclude that the best scientific and commercial information
available indicates that Agrostis rossiae is not in danger of
extinction or likely to become so within the foreseeable future because
of the inadequacy of existing regulatory mechanisms, provided the
existing mechanisms are not weakened or removed.
Factor E. Other Natural or Manmade Factors Affecting Its Continued
Existence
Natural and manmade factors with the potential to affect Agrostis
rossiae include: (1) Competition and hybridization, (2) small
population size, and (3) genetic diversity.
Competition and Hybridization
Previously, Agrostis scabra has been listed as a threat to Agrostis
rossiae, possibly because of competition or hybridization (e.g., Fertig
2000a; 2000c; NatureServe 2010a, p. 1). However, A. scabra is a native
species that does not compete with or restrict A. rossiae (Whipple
2010a, pers. comm.). The thermal areas in which A. rossiae grows have
lethal summer soil temperatures (greater than 45 [deg]C (113 [deg]F))
that preclude the growth of perennial roots and reproduction of any
plant that requires greater than 120 days to complete its life cycle
(Tercek 2003, p. 51). Nonthermal A. scabra is able to germinate in
garden experiments of thermal temperatures; however, nonthermal A.
scabra seldom occurs in the interior of the thermal habitats where A.
rossiae occurs (Tercek 2003, p. 53). Additionally, nonthermal A. scabra
requires a growing season of approximately 160 days in order to flower;
the typical growing season in the transition zone between thermal and
nonthermal ground is approximately 105 days (Tercek 2003, p. 52).
Therefore, even if the nonthermal A. scabra germinated in the
transition zone, it would be unable to reproduce before desiccation
occurred.
Conversely, thermal Agrostis scabra is able to flower at the same
time as Agrostis rossiae (Tercek 2003, p. 10). However, each thermal
area is typically populated by only one of these species because of
differences in microhabitat requirements (e.g., soil temperature, soil
pH) (Tercek 2003, p. 10). A few thermal areas do support populations of
both A. rossiae and thermal A. scabra (Whipple 2010e, pers. comm.);
however, A. rossiae and thermal A. scabra maintain separate
morphologies in these locations and when they are grown under uniform
laboratory conditions (Tercek et al. 2003, p. 1311; Whipple 2010e,
pers. comm.). Additionally, attempts to cross-pollinate A. rossiae and
thermal A. scabra were unsuccessful; however, experiments that are more
rigorous are needed to determine conclusively whether these two
Agrostis species can hybridize (Tercek 2003, p. 19) and to confirm that
there is not a crossbreeding effect that could be a threat to A.
rossiae.
Small Population Size
For general background information on small population size, please
refer to the first paragraph of ``Small Population Size'' under Factor
E. Other Natural or Manmade Factors Affecting Its Continued Existence
in the Five Factor Evaluation for Abronia ammophila section.
We do not have any indication that Agrostis rossiae was ever
present on the landscape over a more extensive range. Nor do we have
any evidence that the populations of A. rossiae are sufficiently small
to experience the problems that occur in some species because of small
population size. Additionally, A. rossiae has the potential to expand
its habitat, although potential habitat may be limited (see
Distribution and Abundance) (Whipple 2010e, pers. comm.). We have no
information indicating that random demographic or environmental events
are a threat to the species because of a small population size.
Therefore, we do not consider small population size to be a threat to
A. rossiae now or in the foreseeable future.
Genetic Diversity
For general background information on genetic diversity, please
refer to the first paragraph of ``Genetic Diversity'' under Factor E.
Other Natural or Manmade Factors Affecting Its Continued Existence in
the Five Factor Evaluation for Abronia ammophila section.
Decreased genetic diversity diminishes a species' ability to adapt
to the selective pressures of a changing environment (Newman and Pilson
1997, p. 360; Ellstrand 1992, p. 77). However, Agrostis rossiae
continually adapts to the changing thermal conditions of its
environment and is able to shift its distribution to follow these
changes (Whipple 2010e, pers. comm.). Therefore, potential decreased
genetic diversity does not appear to be affecting A. rossiae.
Gene flow can also have negative effects on a species (Ellstrand
1992, p. 77). Genes favoring adaptations to a different environment or
hybridization between two species can result (Ellstrand 1992, p. 77).
Gene flow between Agrostis populations is low (Tercek 2003, p. 19).
Therefore, there may be some risk to the species, but we do not fully
understand this risk based on currently available information.
Limited information is available about the genetic diversity of
Agrostis rossiae. We do not have any indication that A. rossiae is at
risk of suffering from reduced genetic diversity and consider it
capable of adapting to changes based on our current understanding of
the species' genetics. Therefore, we do not consider reduced genetic
diversity to be a threat to A. rossiae now or in the foreseeable
future.
[[Page 33939]]
Summary of Factor E
Agrostis scabra is a native species that does not outcompete or
invade the habitat of Agrostis rossiae. Typically, these two species do
not occur together. Additionally, we have no information to suggest
that small population size or reduced genetic diversity limit A.
rossiae. We conclude that the best scientific and commercial
information available indicates that Agrostis rossiae is not in danger
of extinction or likely to become so within the foreseeable future
because of competition or hybridization, small population size, or
reduced genetic diversity.
Finding for Agrostis rossiae
As required by the Act, we considered the five factors in assessing
whether Agrostis rossiae is threatened or endangered throughout all of
its range. We examined the best scientific and commercial information
available regarding the past, present, and future threats faced by A.
rossiae. We reviewed the petition, information available in our files,
and other available published and unpublished information, and we
consulted with recognized A. rossiae experts and other Federal and
State agencies.
The primary factors potentially impacting Agrostis rossiae are
visitor impacts, the invasion of Agrostis scabra, and changing thermal
activity. However, A. scabra is a native species that typically does
not compete with A. rossiae, the existing boardwalks and trails offer
sufficient pathways for visitors to navigate around the thermal areas,
and sufficient regulatory mechanisms exist to prevent human-caused
changes to the thermal basin by groundwater or geothermal development.
Other factors affecting A. rossiae--including nonnative invasive
plants, drought, small population size, and genetic diversity--are
either limited in scope, or lacking evidence apparent to us indicating
that they adversely impact the species as a whole. We have no evidence
that overutilization, disease, or predation are affecting this species.
Although climate change may impact the species in the future, we do not
have enough information to determine that climate change will elicit a
species-level response from A. rossiae. Based on our knowledge of the
species, the regulatory mechanisms to protect the species appear
appropriate.
Based on our review of the best available scientific and commercial
information pertaining to the five factors, we find that the threats
are not of sufficient imminence, intensity, or magnitude to indicate
that Agrostis rossiae is in danger of extinction (endangered), or
likely to become endangered within the foreseeable future (threatened),
throughout all of its range. Therefore, we find that listing A. rossiae
as a threatened or endangered species is not warranted throughout all
of its range.
Significant Portion of the Range
Having determined that Agrostis rossiae does not meet the
definition of a threatened or endangered species, we must next consider
whether there are any significant portions of the range where A.
rossiae is in danger of extinction or is likely to become endangered in
the foreseeable future.
In determining whether Agrostis rossiae is threatened or endangered
in a significant portion of its range, we first addressed whether any
portions of the range of A. rossiae warrant further consideration. We
evaluated the current range of A. rossiae to determine if there is any
apparent geographic concentration of the primary stressors potentially
affecting the species including visitor-related impacts (trampling),
changing thermal activity, nonnative invasive plants, drought, small
population size, and genetic diversity. This species' small range
suggests that stressors are likely to affect it in a uniform manner
throughout its range. Furthermore, we found the stressors are not of
sufficient imminence, intensity, magnitude, or geographically
concentrated such that it warrants evaluating whether a portion of the
range is significant under the Act. We do not find that A. rossiae is
in danger of extinction now, nor is it likely to become endangered
within the foreseeable future throughout all or a significant portion
of its range. Therefore, listing A. rossiae as threatened or endangered
under the Act is not warranted at this time.
We request that you submit any new information concerning the
status of, or threats to, Agrostis rossiae to our Wyoming Ecological
Services Field Office (see ADDRESSES section) whenever it becomes
available. New information will help us monitor A. rossiae and
encourage its conservation. If an emergency situation develops for A.
rossiae, or any other species, we will act to provide immediate
protection.
Species Information for Astragalus proimanthus
Species Description
Astragalus proimanthus is a mat-forming, stemless, perennial herb
measuring 2 to 3 dm (7.9 to 11.8 in.) in diameter (Fertig 2001,
unpaginated) and up to 4 cm (1.6 in.) in height (Dorn 1979 in litt.,
unpaginated). The densely clustered, 1.0- to 3.5-cm-long (0.39- to
1.38-in.-long) leaves are divided into three narrow, 5- to 9-mm-long
(0.2- to 0.4-in.-long) leaflets (small leaflike divisions of a larger
compound leaf) (Fertig and Welp 2001, p. 7). The plants are covered
with fine hairs and appear silvery, with leaflets that are equally
hairy on both sides (Barneby 1964, p. 1153). The 17-mm-long (0.67-in.-
long), asymmetrical, pea-like flowers have five petals: one large broad
upper petal, two side petals, and two lower petals that form a canoe
shape (Fertig and Welp 2001, p. 7). The broad upper petal, called the
banner petal, is constricted along the midline, forming a fiddle shape
(Roberts 1977, p. 63). The yellow to whitish flowers are often tinged
with lavender or pink, especially near the center, and occur in pairs
at the base of the leaves (Fertig and Welp 2001, p. 7). This plant has
a taproot that is woody and branching (Barneby 1964, p. 1153).
Discovery and Taxonomy
The first specimens of Astragalus proimanthus were discovered and
collected 9.7 km (6 mi) north of the town of McKinnon (Sweetwater
County, Wyoming) on June 13, 1946, by H.C. Ripely and R.C. Barneby
(Barneby 1964, p. 1154). A second population was located in 1961
(Barneby 1964, p. 1154). The population discovered in 1961 was
collected from and revisited multiple times in the decades that
followed; however, the population discovered in 1946 could not be
relocated after multiple attempts (Fertig and Welp 2001, p. 8). In
2000, two populations were discovered, one of which may be the original
site collected by Barneby in 1946 as this population was found 9.7 km
(6 mi) north of the town of McKinnon (Fertig and Welp 2001, p. 9).
The flowering plant genus Astragalus is the largest genus of
vascular plants (Montana Plant Life 2010, unpaginated). With the common
names ``milk-vetch'' or ``locoweed'' (family Fabaceae or Leguminosae),
the genus contains more than 2,000 species, which are distributed
worldwide, although they are primarily found in the northern hemisphere
(Barneby 1989, p. 1; Montana Plant Life 2010, unpaginated). Based on
similar morphological features of the flower, calyx (collective term
for the sepals, which are the green, leaflike structures that protect
the delicate inner parts of the flower while it is developing), and
fruits, Astragalus proimanthus is in a taxonomic grouping within
Oropahca (subgenus) with Astragalus gilviflorus (Dubois milkvetch) and
Astragalus hyalinus
[[Page 33940]]
(summer milkvetch), which both occur in Wyoming (Fertig and Welp 2001,
p. 6). A. proimanthus has been considered a descendant of A. hyalinus
(Roberts 1977, p. 63). A. proimanthus is similar to A. hyalinus in its
dwarf habit of growth and short flower with fiddle-shaped banner petal,
but it is dissimilar in having smooth, hairless petals and an earlier
flowering period (by a month or so) (Barneby 1964, p. 1154).
Additionally, A. proimanthus grows in a small, compact form and not in
a large, highly curved cushion characteristic of A. hyalinus. A.
proimanthus resembles A. gilviflorus in its growth form and has a
similar range of numbers of seeds in the fruits; however, unlike A.
gilviflorus, it has narrow, oval-shaped fruit and short, differently
shaped banner petals (Barneby 1964, p. 1154). The only other Astragalus
species in Wyoming with three leaflets have smaller flowers than A.
proimanthus (Fertig 1994, unpaginated). All species within the subgenus
Oropahca have 12 chromosomes (Roberts 1977, p. 1), but it is unknown if
they are interfertile (capable of cross-pollinating or breeding with
other Astragalus species) (Fertig and Welp 2001, p. 14). No evidence of
hybridization between A. proimanthus and other Astragalus species has
been documented (Fertig and Welp 2001, p. 14). Based on this
information, we recognize A. proimanthus as a valid species and a
listable entity.
Biology and Life History
Astragalus proimanthus (precocious milkvetch) is named for its
early flowering period. It has been observed in flower as early as
April 28, and it may continue to bloom until mid-June (Fertig and Welp
2001, p. 14). Astragalus species are typically insect-pollinated;
however, we have no information specific to A. proimanthus (Heidel
2003, p. 19). Both insects and birds have been observed visiting the
flowers of A. proimanthus and may be involved in pollination (Fertig
and Welp 2001, p. 14). Fruits are continuously produced from mid-May
through late July (Roberts 1977, pp. 43, 97). The narrow, oval fruit
pods (7 to 10 mm (0.28 to 0.39 in.) long) are attached to the stems and
are covered in dense, fine hair (Fertig and Welp 2001, p. 7). The fruit
pods contain 11 to 14 seeds (Barneby 1964, p. 1154) that are brown and
2.0 to 3.1 mm (0.08 to 0.12 in.) long (Roberts 1977, p. 64). Fruit
production may be limited during drought years as evidenced by low
fruiting rates observed in 2000 (Fertig and Welp 2001, p. 14). Due to
the absence of seed structures (e.g., winged edges) to enhance
dispersal, seed dispersal appears passive and limited to short
distances (Fertig and Welp 2001, p. 14).
Although Astragalus proimanthus is perennial, its lifespan may be
shorter than is commonly assumed for mat-forming perennials, as is
evidenced by shifts in location of plant subpopulations and
disappearances of previously documented plant occurrences (Fertig and
Welp 2001, pp. 13-14, 17). Longevity is an important life-history trait
for the persistence and survival of species occurring in harsh
environments where recruitment (reproductive success) is variable and
unpredictable (Garcia et al. 2008, p. 261).
Habitat
Astragalus proimanthus is a narrow endemic occurring only on the
shale bluffs of the Henrys Fork River, near the town of McKinnon, which
is in the southern Green River Basin of southwestern Sweetwater County,
Wyoming (Fertig and Welp 2001, p. 8). Sparsely vegetated rims and
gullied upper slopes of benches, bluffs, and mesa-like ridges at
elevations of 1,950 to 2,195 m (6,400 to 7,200 ft) provide habitat for
A. proimanthus (Fertig and Welp 2001, p. 11).
Astragalus proimanthus inhabits cushion plant and bunchgrass
communities dominated by Phlox hoodii (spiny phlox or carpet phlox),
Haplopappus nuttallii (rayless aster), Cryptantha sericea (silky
cryptantha), and Elymus spicatus (bluebunch wheatgrass) in openings
within Artemisia tridentata (big sagebrush) and grasslands intermixed
with Juniperus osteosperma (Utah juniper) (Fertig and Welp 2001, p.
11). A. proimanthus also occurs on gentle slopes at the base of ridges
within a matrix of Artemisia nova (black sagebrush), Sarcobatus
vermiculatus (greasewood), J. osteosperma, and Grayia spinosa (spiny
hopsage) (Fertig and Welp 2001, p. 11). This species grows in fine-
textured limestone shale clays that are dry, shallow, and covered by a
dense layer of coarse cobbles, whitish flakey shale, and dark volcanic
rock (Fertig and Welp 2001, pp. 11-12).
Individual Astragalus proimanthus plants are often separated by
apparently suitable, nonvegetated habitat, and typically occur in
densities ranging from 0.18 to 3.4 plants per square meter (m\2\) (0.15
to 2.8 plants per square yard (yd\2\)) (Fertig and Welp 2001, p. 14).
The habitat in which A. proimanthus grows typically has less than 5 to
10 percent vegetative cover (Fertig and Welp 2001, pp. 11-12). The
absence of plants from seemingly suitable habitat may be the result of
passive seed dispersal (addressed above) or episodic (occurring at
irregular intervals) establishment events, such as gully washouts
(Fertig and Welp 2001, p. 14).
Average annual precipitation where Astragalus proimanthus occurs is
25 cm (9.8 in.), with peak precipitation events occurring in May and
June (Martner 1986 as cited in Fertig and Welp 2001, p. 12). Mean
annual temperature is 4.4 [deg]C (40 [deg]F), with mean lows of -14.4
[deg]C (6 [deg]F) in January, and mean highs of 28.9 [deg]C (84 [deg]F)
in July (Martner 1986 as cited in Fertig and Welp 2001, p. 12). The
average number of days per year at or below freezing are 225 (Martner
1986 as cited in Fertig and Welp 2001, p. 12).
Distribution and Abundance
The distribution of Astragalus proimanthus consists of 3
populations which are made up of 26 subpopulations (Fertig and Welp
2001, pp. 12-13; Heidel 2010a, pers. comm.). The largest population
contains 21 subpopulations and occurs within 3.2 km (2 mi) of the
Henrys Fork River along an 8-km (5-mi) stretch (WNDD in litt. 2010,
unpaginated). The second largest population consists of four
subpopulations and occurs 12.9 km (8 mi) further upstream on the Henrys
Fork River, near the mouth of Cottonwood Creek (WNDD in litt. 2010,
unpaginated). The smallest population consists of one subpopulation and
occurs 2.5 km (1.5 mi) north of the largest population, along Lane
Meadow Creek--a tributary to the Henrys Fork River (WNDD in litt. 2010,
unpaginated). The entire distribution of A. proimanthus is limited to
an area of less than 129.5 ha (320 ac) within an area of 6.4 by 22.5 km
(4 by 14 mi) (Fertig and Welp 2001, p. 8).
Population estimates of A. proimanthus have varied widely, probably
reflecting variability in survey methods and discovery of new
subpopulations (Fertig and Welp 2001, p. 13). In 1980, prior to the
discovery of all 26 subpopulations, an estimated 200 plants were
documented as occurring within 2 populations (Dorn 1980, p. 49). The
first survey to inventory the entire known distribution was completed
in May of 1981, with the total number of A. proimanthus plants
estimated at 22,000 plants occurring on 97.1 ha (240 ac) (Whiskey Basin
Consultants 1981, p. 5). Conclusions from field studies conducted in
1989 are that, although the distribution of A. proimanthus was limited,
subpopulations within that distribution were large, containing
thousands of individual plants; the total population size was estimated
at 25,000 to 40,000 individuals (Fertig and Welp
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2001, p. 13). However, the 1989 field studies focused on identifying
new subpopulations and initiating a monitoring program, not on
conducting a quantitative census (Fertig and Welp 2001, p. 13). In June
2000, a survey of 11 subpopulations representing the 3 known
populations, conducted by the WNDD, resulted in a count of 2,644
individuals; this was extrapolated to a minimum total population
estimate of 10,500 to 13,000 individuals (Fertig and Welp 2001, p. 13).
The distribution of A. proimanthus may be associated with the
presence of a light-colored shale formation, where it is the uppermost
soil layer (Whiskey Basin Consultants 1981, p. 9). The Henrys Fork
River has eroded this shale formation away in some areas, causing it to
be exposed over a distance of 9 km (5.5 mi) near the river (Whiskey
Basin Consultants 1981, p. 9). Approximately 95 percent of the known
occurrences of A. proimanthus have been found on BLM-administered
lands, with 4 percent occurring on State lands, and 1 percent on
private lands (Heidel 2010b, pers. comm.).
The WNDD has designated Astragalus proimanthus as a plant species
of concern with ranks of G1 and S1 (Heidel 2007, p. 3). For background
information on G1 and S1 rankings, please refer to the last paragraph
under Distribution and Abundance in the Species Information for Abronia
ammophila section. Since A. proimanthus is endemic to Wyoming, the
Wyoming occurrences encompass this species' entire global range.
Trends
Population trends for Astragalus proimanthus are difficult to
determine because survey methodologies have not remained consistent,
baseline data are lacking, and precipitation has varied significantly
during survey years (Fertig and Welp 2001, p. 13). Shifts in the
distribution suggest that A. proimanthus may be shorter-lived than is
often assumed for mat-forming perennials (Fertig and Welp 2001, p. 14).
The importance of yearly fluctuations in precipitation and temperature
to the establishment and survival of this species is unknown (Fertig
and Welp 2001, p. 14).
Population counts and distribution of Astragalus proimanthus along
established transects have varied during the past two decades (Fertig
and Welp 2001, p. 14). Five transects were established in 1989 to
evaluate changes in abundance and density of plants (Marriott 1989,
Appendix D). Surveys from two transects monitored from 1989 to 1998
showed a long-term increase in numbers and densities of plants (Fertig
and Welp 2001, pp. 37-47). However, numbers along a third transect
decreased by 7 percent from 1989 to 1998, and then the transect could
not be relocated in 2000 possibly due to a local extirpation of plants
(Fertig and Welp 2001, pp. 14, 37-47). Surveys from the fourth transect
showed a steady decline in overall plant numbers, reaching a 43 percent
decrease in numbers by 2000 (Fertig and Welp 2001, pp. 14, 37-47).
Surveys from the fifth transect revealed short-term oscillations in the
population size, with numbers increasing between 1989 and 1998 and then
decreasing 8 percent by 2000 (Fertig and Welp 2001, pp. 37-47). Changes
in numbers and plant densities may be attributed to the short lifespans
of individual plants or the lack of new plants becoming established
(Fertig and Welp 2001, p. 14). Localized increases and decreases in
population numbers and density may be expected for this species, as
evidenced by the variable numbers and changes in spatial distributions
along survey transects (Fertig and Welp 2001, p. 40). However, overall
monitoring data suggest that the main population along the bluffs of
the Henrys Fork River was relatively stable from 1998 to 2000 despite
localized shifts in distribution (Fertig and Welp 2001, p. 14).
Five Factor Evaluation for Astragalus proimanthus
Information pertaining to Astragalus proimanthus in relation to the
five factors provided in section 4(a)(1) of the Act is discussed below.
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
The following potential factors that may affect the habitat or
range of Astragalus proimanthus are discussed in this section,
including: (1) energy development, (2) road construction, (3) off-road
vehicle use, (4) range improvements, (5) disposal sites, (6) nonnative
invasive plants, (7) fire, and (8) climate change and drought.
Energy Development
Energy development has been identified as a potential threat to
Astragalus proimanthus (Marriot 1989, p. 8, Fertig and Welp 2001, p.
16). The distribution of A. proimanthus is limited to Sweetwater
County, Wyoming (WNDD in litt. 2010, unpaginated). Sweetwater County
sits atop the coal seams and oil and gas reserves of the Upper Green
River Basin, which by some estimates contain 10 percent of the nation's
total onshore natural gas reserves, as well as the largest known trona
(a source of sodium carbonate) deposit in the world (Headwaters
Economics 2009, p. 26). Uranium and coal (Headwaters Economics, p. 26)
as well as oil shale resources (Congressional Research Service 2008, p.
3) occur throughout the county. There also is the potential for wind
energy development in Sweetwater County (BLM 2010a, unpaginated).
Oil and gas exploration and extraction; coal, uranium, and trona
mining; and oil shale and wind energy development may involve ground-
disturbing actions that have the potential to remove or disturb
Astragalus proimanthus and its habitat (Marriott 1989, p. 8; Fertig and
Welp 2001, p. 16). Oil and gas exploration and coal mining may involve
drilling, using explosives, driving heavy earth-moving equipment off
road, clearing land for resource extraction or project infrastructures,
and constructing roads and utility lines. Oil shale development may
involve converting oil shale into crude oil through a process called
destructive distillation, which may require land removal (Congressional
Research Service 2008, p. 4). Wind energy development involves clearing
land for constructing turbine sites and infrastructure including
utility lines and roads. Additionally, all energy development may
result in increased human use and vehicular traffic, which can result
in trampling and increased erosion in the area.
In 2000, seismic explorations took place near the mouth of
Cottonwood Creek, where a population of Astragalus proimanthus occurs
(Fertig and Welp, 2001, p. 16). Associated road construction may have
disturbed A. proimanthus habitat, but there is no indication that
plants were removed by these activities and any population-level
effects are unknown. Presently, there is no ongoing energy development
near the known occurrences of A. proimanthus on BLM-administered lands
(Glennon 2010a, pers. comm.).
Astragalus proimanthus is a special status species designated by
the BLM State Director as sensitive (BLM 1997, p. 19). This status
requires that potential habitat on Federal or split estate (i.e., mixed
surface and mineral ownership) lands be searched to determine if
sensitive plants are located in the project area before the project
occurs (BLM 1997, p. 19). Areas with special status plant populations
are closed to activities that would adversely affect them, including
surface disturbances, locating new mining claims, mineral material
sales, all off-road vehicle (ORV)
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use, and use of explosives and blasting (BLM 1997, p. 19).
In the Green River Resource Management Plan (RMP), the BLM has
established a Special Status Plant Species Area of Critical
Environmental Concern (ACEC) that covers four plant species including
Astragalus proimanthus (BLM 1997, pp. 19, 34). This ACEC protects 100
percent of A. proimanthus that occurs on BLM land (BLM 2011,
unpaginated). This ACEC is closed to energy development activities that
have the potential to adversely affect A. proimanthus and its habitat.
Prohibited activities include surface disturbing activities and surface
occupancy (such as leasable mineral exploration and development or
construction of long-term facilities or structures), mineral material
sales, and use of explosives and blasting (BLM 1997, pp. 19, 34). The
ACEC has provisions by which any newly located A. proimanthus
individuals and habitat can be added to the ACEC by an amendment to the
RMP (BLM 1997, pp. 19, 34).
Additionally, BLM-administered lands under a 48.6-ha (120-ac)
fenced enclosure around one of the subpopulations of Astragalus
proimanthus, north of the town of McKinnon, have been withdrawn from
mineral exploration and mining (BLM 1999, p. 6; Glennon 2010a, pers.
comm.). The BLM has committed to pursuing the withdrawal of mining
claims in all areas of the Special Status Plants Species ACEC (BLM
1997, p. 34).
Although occurrences of Astragalus proimanthus on BLM-administered
lands are protected from the impacts of energy development, future
energy development remains a potential threat to occurrences of A.
proimanthus that are not located on Federal land. However, this
potential threat is unlikely to rise to the level of a threat to the
species as the vast majority of known occurrences (95 percent) of A.
proimanthus are located on BLM-administered lands (Heidel 2010b, pers.
comm.; WNDD in litt. 2010, unpaginated). Therefore, we do not consider
energy development to be a threat to A. proimanthus now or in the
foreseeable future.
Road Construction
Roads can destroy or modify habitat and increase human access that
may lead to trampling or the introduction of nonnative invasive plants
(discussed below). Additionally, road construction can lead to
increased erosion, and vehicle traffic on unimproved roads can result
in increased atmospheric dust and dust deposition on vegetation.
Habitat for Astragalus proimanthus has been lost at several
locations due to road construction (Fertig and Welp 2001, p 16).
Wyoming State Highway 1 intersects two subpopulations (Fertig and Welp
2001, p. 13). Several two-track vehicle trails are located near
populations of A. proimanthus (BLM 1997, p. 199). During the summer of
1993, BLM personnel documented surface disturbance due to traffic; this
was partially associated with vehicles accessing the unauthorized
McKinnon Dump, which is no longer in use and has since been reclaimed
(BLM 1997, p. 199).
On BLM lands, special status plant populations are closed to
activities that could adversely affect them or their habitat (BLM 1997,
p. 19), and the ACEC is closed to all direct surface-disturbing road
construction (BLM 1997, p. 34). Future road development is a potential
threat to occurrences of Astragalus proimanthus that are not on BLM-
managed lands. However, future road construction does not rise to the
level of a threat to A. proimanthus, because the species primarily
occurs on BLM-administered lands and, therefore, is protected by the
provisions in the ACEC and its designation as a special status plant
species (BLM 1997, pp. 19, 34). Therefore, we do not consider road
construction to be a threat to A. proimanthus now or in the foreseeable
future.
Off-Road Vehicle Use
The use of ORVs is both a means of transportation and recreation in
Wyoming. Approximately 35.5 percent of Wyoming's 506,000 residents use
ORVs for recreational purposes (Foulke et al. 2006, p. 3). During 2004
and 2005, Sweetwater County had the fifth highest ORV permit sales in
the State (Foulke et al. 2006, pp. 8-9).
The area of BLM-administered land in Sweetwater County, Wyoming,
where Astragalus proimanthus occurs has not experienced the high level
of ORV use seen in some other areas of Wyoming (Glennon 2010a, pers.
comm.). There are no large communities nearby to support local ORV
recreational activities. The closest town (within 3.2 km (2 mi) of the
nearest populations of A. proimanthus) is McKinnon, with a population
of 49 in 2000 (U.S. Census Bureau 2010, unpaginated). The larger
communities of Green River (estimated population of 12,411 in 2009),
Rock Springs (estimated population of 20,905 in 2009), and Evanston
(estimated population of 11,958 in 2009) (U.S. Census Bureau 2009,
unpaginated) are 78.9, 106.2, and 120.7 km (49, 66, and 75 mi) from
McKinnon, respectively. There are many ORV opportunities closer to
these communities than those on the BLM-administered lands near the
town of McKinnon.
In addition, Astragalus proimanthus habitat is generally not
attractive to ORV users. Recreational destinations in the area where A.
proimanthus occurs are largely limited to a few historic sites and
trails (BLM 1997, pp. 4-6). Available two-track vehicle trails provide
access to most common destinations, such as water sources and hunting
campsites, so that off-road access is not often necessary (Glennon
2010a, pers. comm.). Additionally, A. proimanthus occurs on slopes and
ridges (Fertig and Welp 2001, p. 11) that are not conducive to ORV
travel that is destination-oriented.
Finally, the ACEC is closed to ORV use (BLM 1997, p. 72). However,
there are no physical barriers to keep ORVs out of the ACEC, except for
in the 48.6-ha (120-ac) fenced exclosure (Glennon 2010a, pers. comm.).
At other locations in southwestern Wyoming, violators of BLM and U.S.
Forest Service travel restrictions on ORV use have been reported (WGFD
2010, unpaginated). The potential for impacts from illegal ORV use on
BLM-administered lands is possible even within the ACEC. However,
impacts from illegal ORV use are unlikely due to the low human
populations in the area, the difficulty of traversing the habitats
occupied by Astragalus proimanthus, and the greater likelihood of
enforcement of the prohibition of ORV use within an ACEC due to
critical resource concerns (BLM 1997, p. 110). Therefore, we do not
consider ORV use to be a threat to A. proimanthus now or in the
foreseeable future.
Range Improvements
Habitat modifications due to range improvement projects for
livestock have been identified as a potential threat to Astragalus
proimanthus (Marriott 1989, p. 8). However, this was prior to the
designation of the ACEC that provides special protections for A.
proimanthus (BLM 1997, p. 34). As stated in the Green River RMP, within
the ACEC: ``Livestock grazing objectives and management practices will
be evaluated and, as needed, modified to be consistent with the
management objectives for this area'' (BLM 1997, p. 34). The plan also
specifies, ``Grazing systems will be designed to achieve desired plant
communities and proper functioning conditions of watersheds (upland and
riparian)'' (BLM 1997, p. 34). Additionally, no wild horse traps will
be constructed within this area (BLM 1997, p. 34). Movement of
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livestock between areas of known use and range improvements will be
evaluated and monitored, and locations of range improvements will be
modified, if necessary, to ensure that the habitat where A. proimanthus
occurs will not be trampled (Glennon 2010a, pers. comm.). The fact that
populations from 1989 through 2000 were relatively stable (Fertig and
Welp 2001, p. 14) suggests that range management did not adversely
affect A. proimanthus populations during that time. No impacts from
livestock have been noted recently (Glennon 2010a, pers. comm.). Since
1997, range management practices also are evaluated pursuant to the
management objectives of the ACEC (BLM 1997, p. 19). Additionally,
known locations of A. proimanthus are protected and closed to surface-
disturbing activities or any disruptive activity that could adversely
affect the plants or their habitat (BLM 1997, p 19). Therefore, we do
not consider range improvements to be a threat to A. proimanthus now or
in the foreseeable future.
Disposal Sites
Disturbance associated with garbage disposal sites (dumps) has been
identified as a potential threat to Astragalus proimanthus (Marriott
1989, p. 8). Surveys conducted by the BLM in 1993 and 1994 documented
disturbances to the habitat of A. proimanthus due to the presence of
the McKinnon Dump (BLM 1997, p. 199). The McKinnon Dump was an illegal
dump located on BLM land (Board of County Commissioners of Sweetwater
County 1992, unpaginated). The BLM and Sweetwater County worked
together to clean up and reclaim the McKinnon Dump (Board of County
Commissioners of Sweetwater County 1992, unpaginated; BLM 1997, p.
199). Since 1997, the ACEC appears to have effectively protected A.
proimanthus from surface disturbance, such as dumps, on BLM-
administered lands (BLM 1997, p. 34). Therefore, we do not view
disposal sites to be a threat to A. proimanthus now or in the
foreseeable future.
Nonnative Invasive Plants
For general background information on nonnative invasive plants,
please refer to the first paragraph of ``Nonnative Invasive Plants''
under Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range in the Five Factor Evaluation for
Abronia ammophila section.
We have no evidence of impacts to Astragalus proimanthus from
nonnative invasive plants. A. proimanthus grows in shallow, dry soils
that support only sparse vegetation (Fertig and Welp 2001, pp. 11-12).
The characteristics of its harsh habitat may explain why no nonnative
invasive plants have been reported in proximity to the known
occurrences. Therefore, we do not consider nonnative invasive plants to
be a threat to this species now or in the foreseeable future.
Fire
We find the potential impact of wildfire to the species to be
minimal due to the sparse vegetation cover in habitats occupied by
Astragalus proimanthus. From 1980 through 2009 (29 years), seven
wildfires occurred in the area BLM mapped as potential habitat for
Astragalus proimanthus (Caldwell 2011, pers. comm.). However, no fires
burned in areas with known occurrences of A. proimanthus; moreover, the
total acreage burned during this 29-year period was 0.3 ha (0.7 ac)
(Caldwell 2011, pers. comm.). All seven wildfires were caused by
lightning strikes to isolated junipers, and only that individual tree
burned (Stephenson 2011, pers. comm.). Areas of barren ground between
widely spaced vegetation and low fuel loads prevent fires from
spreading far beyond points of ignition (Brooks and Pyke 2002, p. 5),
as the existence of adequate fuels is one of the requirements for a
fire to start and continue to burn (Moritz Lab 2010, entire).
Therefore, we do not consider fire to be a threat to this species now
or in the foreseeable future.
Climate Change and Drought
For general background information on climate change, please refer
to the first paragraphs of ``Climate Change'' under Factor A. The
Present or Threatened Destruction, Modification, or Curtailment of Its
Habitat or Range in the Five Factor Evaluation for Abronia ammophila
section.
Although assessing the magnitude and type of effect climate change
may have on Astragalus proimanthus is complex, we believe climate
change has the potential to affect the species given the predictions
discussed previously of increased springtime temperatures, decreased
springtime precipitation, and increased drought. The importance of
yearly fluctuations in precipitation and temperature on the
establishment and survival of A. proimanthus is unknown (Fertig and
Welp 2001, p. 14). However, drought is not unusual or unnatural in
Wyoming. Severe or extreme drought conditions occur more than 20
percent of the time over the southwestern regions of the State (Curtis
and Grimes 2004, Chapter 6.2). As noted previously, monitoring data
suggest that the main population along the bluffs of the Henrys Fork
River was relatively stable from 1998 to 2000 (Fertig and Welp 2001, p.
14). During this same period, this species' habitat experienced drought
conditions, including severe droughts (Curtis 2004, unpaginated).
Although climate change may affect the duration and severity of drought
in some locations, we do not have information to suggest A. proimanthus
is unlikely to be able to respond to this potential stressor.
Therefore, we do not consider climate change and drought to be a threat
to this species now or in the foreseeable future.
Summary of Factor A
Occurrences of Astragalus proimanthus have experienced historical
impacts from road development and illegal trash dumps. Additionally,
seismic exploration for oil and gas occurred near one population where
associated road construction may have disturbed A. proimanthus habitat,
but there is no indication that plants were destroyed. Currently, the
habitat disturbance due to the McKinnon dump has effectively been
addressed. The special species status of A. proimanthus and the
provisions in the ACEC are adequate to alleviate the threats to A.
proimanthus from energy development, road construction, ORV use, range
improvements, and other land uses that have the potential to disturb
the habitat of A. proimanthus. Although potential threats on State and
private lands may exist, such as ORV use or range improvements, only 5
percent of this species' distribution occurs on private lands, and no
impacts to the species on private lands has been documented.
In summary, we note that procedural considerations for amending the
Green River RMP to ensure that all individual Astragalus proimanthus
plants on BLM-administered lands are protected by the Special Status
Plant Species ACEC (BLM 1997, pp. 19-20, 34) are lengthy and may not
accurately delineate the oscillating distributions and new discoveries
of this species. However, maintenance actions may be used in certain
situations including new population discoveries and species' range
shifts (see Factor D: Bureau of Land Management below). Therefore, we
find that the protections provided by the special status plant species
designation (BLM 1997, p. 19) in combination with the protections
provided by the Special Status Plant ACEC, as documented in the Green
River RMP (BLM 1997, p. 34), provide
[[Page 33944]]
effective protection to 95 percent of the population of A. proimanthus.
We conclude that the best scientific and commercial information
available indicates that Astragalus proimanthus is not in danger of
extinction or likely to become so within the foreseeable future because
of the present or threatened destruction, modification, or curtailment
of its habitat or range.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Astragalus proimanthus is not known to be collected for any
purposes. One species of this genus, Astragalus membranaceus (Huang
qi), has been used in traditional Chinese medicine for thousands of
years (University of Maryland 2006, unpaginated). However, this species
is native to Asia, and Astragalus species that grow in the United
States do not share similar medicinal properties (University of
Maryland 2006, unpaginated). We have no information to indicate that A.
proimanthus is threatened by overutilization for commercial,
recreational, scientific, or educational purposes.
We conclude that the best scientific and commercial information
available indicates that Astragalus proimanthus is not in danger of
extinction or likely to become so within the foreseeable future because
of overutilization for commercial, recreational, scientific, or
educational purposes.
Factor C. Disease or Predation
Disease
Astragalus proimanthus is not known to be affected or threatened by
any disease. Therefore, we do not consider disease to be a threat to A.
proimanthus now or in the foreseeable future.
Predation--Grazing and Herbivory
Grazing and herbivory effects on Astragalus proimanthus have not
been studied. Bird or insect predation on many A. proimanthus flowers
was noted on at least one occasion (Barneby 1964, p. 1154). Most
occurrence reports do not mention any instances of herbivory (WNDD in
litt. 2010, unpaginated; Marriot 1989, p. 16). Domestic sheep
apparently do not graze A. proimanthus (Mutz 1981, p. 6), and direct
impacts from grazing are thought to be unlikely due to the plant's low
stature, coarse pubescence (fine, short hairs), and low palatability
(Mutz 1981, p. 6; Marriott 1989, unpaginated; Fertig and Welp 2001, p.
14). Therefore, we do not consider predation to be a threat to A.
proimanthus now or in the foreseeable future.
Summary of Factor C
We conclude that the best scientific and commercial information
available indicates that Astragalus proimanthus is not in danger of
extinction or likely to become so within the foreseeable future because
of disease or predation.
Factor D. The Inadequacy of Existing Regulatory Mechanisms
The Act requires us to examine the adequacy of existing regulatory
mechanisms with respect to threats that may place Astragalus
proimanthus in danger of extinction or likely to become so in the
future. Existing regulatory mechanisms that could have an effect on
potential threats to A. proimanthus include (1) Federal laws and
regulations; (2) State laws and regulations; and (3) local land use
laws, processes, and ordinances. Most (95 percent) of A. proimanthus
occurs on Federal land; therefore, the discussion below focuses on
Federal laws. Actions adopted by local groups, States, or Federal
entities that are discretionary, including conservation strategies and
guidance, are not regulatory mechanisms; however, we may discuss them
in relation to their effects on potential threats to the species.
Federal Laws and Regulations
Bureau of Land Management
As discussed previously, the special status species designation and
the Special Status Plant Species ACEC, as documented in the Green River
RMP (BLM 1997, pp. 19, 34), have adequate provisions to effectively
protect 95 percent of the population distribution of Astragalus
proimanthus. An RMP, the primary management tool that implements
regulatory mechanisms, goes through revisions approximately every 15
years, and a revision to the Green River RMP is anticipated by 2013
(Dana 2010b, pers. comm.). This revision has been started and the
special status plant designation, based on the BLM State Directors'
designation, will carry over into the newly revised RMP.
Astragalus proimanthus was designated by the BLM State Director as
a BLM State-sensitive species (BLM 2010b, p. 23). The BLM focuses
sensitive species management on maintaining species habitat in
functional ecosystems, ensuring the species is considered in land
management decisions, preventing a need to list the species under the
Act, and prioritizing conservation that emphasizes habitat (BLM 2010b,
p. 1). The BLM sensitive species are automatically included as special
status plant species, along with candidate, threatened, and endangered
plant species (BLM 1997, p. 19), and locations of special status plant
species are closed to activities that could adversely affect them or
their habitat (BLM 1997, p. 19). Additionally, the ACEC delineates
known distributions of A. proimanthus and its essential habitat, while
furthering the protection of newly discovered locations on BLM lands
(BLM 1997, p. 34). The BLM conducts searches to identify additional
areas where A. proimanthus may be located (BLM 1997 p. 34). In January
2011, the BLM took a maintenance action on the Green River RMP to
include all newly discovered locations of A. proimanthus on BLM-
administered lands in the ACEC (BLM 2011, unpaginated). Maintenance
actions are based on new or changed data, and document or refine
previously approved decisions incorporated into an RMP (43 CFR 1610.5-
4). A maintenance action does not require formal public involvement and
interagency coordination as this action is limited to refining or
documenting a previously approved decision incorporated in the plan (43
CFR 1610.5-4). As a result of this maintenance action 100 percent of
the known locations of A. proimanthus occurring on BLM-administered
lands are protected by the ACEC (BLM 2011, unpaginated).
National Environmental Policy Act
All Federal agencies are required to adhere to the NEPA for
projects they fund, authorize, or carry out. For more information about
NEPA, please refer to Factor D. The Inadequacy of Existing Regulatory
Mechanisms in the Five Factor Evaluation for Abronia ammophila section.
State and Local Laws and Regulations
The remaining 5 percent of the distribution of A. proimanthus
occurs on State and private lands, and are not protected by regulatory
mechanisms.
Summary of Factor D
The existing ACEC appears to adequately protect the majority (95
percent) of the habitat of Astragalus proimanthus. We expect that A.
proimanthus and its habitat will be generally protected from direct
human disturbance. We have no evidence of impacts to A. proimanthus
from inadequate regulatory mechanisms.
We conclude that the best scientific and commercial information
available indicates that Astragalus proimanthus is not in danger of
extinction or likely to become so within the foreseeable future because
of inadequate regulatory mechanisms.
[[Page 33945]]
Factor E. Other Natural or Manmade Factors Affecting Its Continued
Existence
Natural and manmade factors with the potential to affect Astragalus
proimanthus include: (1) Small population size, (2) pollination, and
(3) genetic diversity.
Small Population Size
For background information, please refer to the first paragraph of
``Small Population Size'' under Factor E. Other Natural or Manmade
Factors Affecting Its Continued Existence in the Five Factor Evaluation
for Abronia ammophila section.
We have no evidence that the populations of Astragalus proimanthus
are experiencing the problems that occur in some species with small
population size. We do not have any indication that A. proimanthus was
ever present on the landscape over a more extensive range. We also have
no information indicating that random demographic or environmental
events are a threat to the species because of its small population
size. Therefore, we do not consider small population size to be a
threat to A. proimanthus now or in the foreseeable future.
Pollination
Please refer to the first paragraph of ``Pollination'' under Factor
E. Other Natural or Manmade Factors Affecting Its Continued Existence
in the Five Factor Evaluation for Abronia ammophila section for
background information. Astragalus proimanthus is believed to have been
historically rare, with populations appearing to be stable (Fertig and
Welp 2001, p. 13). We have no information indicating that a lack of
pollinators is a threat to the species. Therefore, we do not consider
lack of pollinators to be a threat to A. proimanthus now or in the
foreseeable future.
Genetic Diversity
For background information, please refer to the first paragraph of
``Genetic Diversity'' under Factor E. Other Natural or Manmade Factors
Affecting Its Continued Existence in the Five Factor Evaluation for
Abronia ammophila section. We have no information indicating that a
lack of genetic diversity is a threat to the species. Therefore, we do
not consider lack of genetic diversity to be a threat to A. proimanthus
now or in the foreseeable future.
Summary of Factor E
We have no information to suggest that Astragalus proimanthus was
ever present across the landscape with a broader range. We have no
indication that A. proimanthus is suffering from any problems
associated with small population size. We also have no information
showing that A. proimanthus is suffering from low pollination rates or
reduced genetic diversity. Therefore, we conclude that the best
scientific and commercial information available indicates that
Astragalus proimanthus is not in danger of extinction or likely to
become so within the foreseeable future because of small population
size, reduced pollination, or reduced genetic diversity.
Finding
As required by the Act, we considered the five factors in assessing
whether Astragalus proimanthus is threatened or endangered throughout
all of its range. We examined the best scientific and commercial
information available regarding the past, present, and future threats
faced by the species. We reviewed the petition, information available
in our files, other available published and unpublished information,
and we consulted other Federal and State agencies.
Occurrences of Astragalus proimanthus experienced historical
impacts from road development and illegal trash dumps. Additionally,
seismic exploration for oil and gas occurred near one population, with
no known impacts to the species. However, the provisions in the ACEC
now in place are adequately alleviating any potential threats to A.
proimanthus from energy development, road construction, ORV use, range
improvements, and other land uses that have potential to disturb A.
proimanthus and its habitat. Although potential threats on State and
private lands exist, such as ORV use or range improvements, no impacts
to the plants on these lands have been documented or are reasonably
anticipated. We have no information to show that A. proimanthus is
threatened by overutilization for commercial, recreational, scientific,
or educational purposes at this time. We conclude that the best
scientific and commercial information available indicates that
Astragalus proimanthus is not in danger of extinction or likely to
become so within the foreseeable future because of climate change,
drought, nonnative invasive plants, fire, small population size, lack
of pollinators, or reduced genetic diversity. We have no information
regarding actual or potential adverse impacts due to overutilization,
disease, inadequate regulatory mechanisms, reduced genetic diversity,
or reduced pollination.
Based on our review of the best available scientific and commercial
information pertaining to the five factors, we find that the threats
are not of sufficient imminence, intensity, or magnitude to indicate
that Astragalus proimanthus is in danger of extinction (endangered), or
likely to become endangered within the foreseeable future (threatened),
throughout all of its range. Therefore, we find that listing A.
proimanthus as a threatened or endangered species is not warranted
throughout all of its range.
Significant Portion of the Range
Having determined that Astragalus proimanthus does not meet the
definition of a threatened or endangered species, we must next consider
whether there are any significant portions of the range where A.
rossiae is in danger of extinction or is likely to become endangered in
the foreseeable future.
In determining whether Astragalus proimanthus is threatened or
endangered in a significant portion of its range, we first addressed
whether any portions of the range of A. proimanthus warrant further
consideration. We evaluated the current range of A. proimanthus to
determine if there is any apparent geographic concentration of the
primary stressors potentially affecting the species including energy
development, road construction, ORV use, range improvements, and other
land uses. This species' small range suggests that stressors are likely
to affect it in a uniform manner throughout its range. However, we
found the stressors are not of sufficient imminence, intensity,
magnitude, or geographically concentrated such that it warrants
evaluating whether a portion of the range is significant under the Act.
We do not find that A. proimanthus is in danger of extinction now, nor
is likely to become endangered within the foreseeable future throughout
all or a significant portion of its range. Therefore, listing A.
proimanthus as threatened or endangered under the Act is not warranted
at this time.
We request that you submit any new information concerning the
status of, or threats to, Astragalus proimanthus to our Wyoming
Ecological Services Field Office (see ADDRESSES section) whenever it
becomes available. New information will help us monitor A. proimanthus
and encourage its conservation. If an emergency situation develops for
A. proimanthus, or any other species, we will act to provide immediate
protection.
[[Page 33946]]
Species Information for Penstemon gibbensii
Species Description
Penstemon gibbensii is a perennial forb (herbaceous plant that is
not a grass) averaging approximately 23 cm (9 in.) in height (Dorn
1990a, p. 3). Its leaves are long and narrow, often folded down the
length of the mid-rib, pubescent (covered with fine, short hairs) to
smooth, and typically less than 5 mm (0.2 in.) wide (Fertig and
Neighbours 1996, p. 4). Populations at lower elevations are
conspicuously more pubescent, possibly as an adaptation to conserve
moisture in warmer habitats (Dorn 1990a, p. 6). The bright blue flower
is tube-shaped, 15 to 20 mm (0.6 to 0.8 in.) long, and may appear from
early June to September, depending on moisture levels (Fertig 2000d,
unpaginated).
Taxonomy
Penstemon, with an estimated 271 species, is the largest plant
genus endemic to North America, and the Intermountain Region represents
the center of diversity (Wolfe et al. 2006, p. 1699). In the early
1970s, Robert Gibbens collected the first specimens of Penstemon
gibbensii in Sweetwater County, Wyoming (Dorn 1982, p. 334). These
specimens were sent to a Penstemon specialist for identification and
subsequently lost (Dorn 1990a, p. 1). In 1981, Robert Dorn resurveyed
the area and relocated P. gibbensii in the field (Dorn 1982, p. 334;
Heidel 2009, p. 1). P. gibbensii was determined to be a new,
undescribed species based on its morphology (Dorn 1982, p. 334; Fertig
and Neighbours 1996, pp. 4-6). This species has been reproductively
isolated for some time as each known population of P. gibbensii
exhibits slight morphological and habitat differences (Dorn 1989 as
cited in Fertig and Neighbours 1996, pp. 3-4).
Penstemon gibbensii is a member of the Scrophulariaceae (figwort or
snapdragon) family (Dorn 1982, p. 334; Fertig and Neighbours 1996, p.
2). Similar species include Penstemon cyananthus (Wasatch beardtongue),
Penstemon fremontii (Fremont's beardtongue), Penstemon saxosorum
(upland beardtongue), and Penstemon scariosus (White River beardtongue)
(Fertig 2000d, unpaginated). P. gibbensii, which occurs at a lower
elevation than P. saxosorum, can be distinguished by stems that are
pubescent nearly to the base, narrower leaves, and corollas (all the
petals of the flower) that are pubescent inside and out (Dorn 1982, p.
334). P. gibbensii is more pubescent than P. cyananthus, and has much
narrower leaves (Dorn 1982, p. 334). The current taxonomic status of P.
gibbensii is accepted (Integrated Taxonomic Information System 2010b,
unpaginated). We recognize P. gibbensii as a valid species and a
listable entity.
Biology and Life History
Reproduction of Penstemon gibbensii is by seed, with no evidence of
vegetative reproduction (Fertig and Neighbours 1996, p. 16). Based upon
flower color and shape, this species is probably insect pollinated
(Fertig and Neighbours 1996, p. 16). Bees have been seen visiting
flowers at sites in Colorado and Utah (Langton 2010, pers. comm.).
Fruits are oval, light-brown capsules (Fertig 2000d, unpaginated).
Seeds are probably dispersed primarily by gravity or wind (Fertig and
Neighbours 1996, p. 16). P. gibbensii appears to have minimal
reproductive success, as evidenced by below-normal seedling numbers in
most years due to dry conditions (Heidel 2009, p. 21). In 1985, 1988,
and 1991, at three transects in the Cherokee Basin occurrence, 0 to 56
percent of P. gibbensii plants were seedlings (Warren in litt. 1992,
Table 2). Seedling establishment is probably episodic and dependent on
occasional years with adequate summer moisture (Fertig and Neighbours
1996, p. 16). P. gibbensii is able to take advantage of summer
precipitation, as it is a warm-season species (Warren in litt. 1992,
unpaginated).
No information was available regarding chilling requirements for
seeds of P. gibbensii. However, close relatives (i.e., Penstemon
cyananthus, Penstemon fremontii, and Penstemon scariosus) have seeds
that are largely dormant at harvest and require a long chilling period
prior to germination (Meyer and Kitchen 1994, p. 354). These species
have evolved seed germination mechanisms that permit the carryover of
seeds between years as a persistent seed bank, which maximizes the
probability of seedling survival in favorable years (Meyer and Kitchen
1994, p. 363). Recognizing the similarities between these Penstemon
species and their climatic conditions, we assume that P. gibbensii also
requires a chilling period and has a persistent seed bank.
Habitat
Penstemon gibbensii occurs in a cold steppe climate on barren shale
or sandy-clay slopes (Dorn 1990a, p. 6). Habitat is often located on
steep upper or middle slopes eroding below a more resistant caprock
(Heidel 2009, p. 13). Slopes are generally 20 to 30 degrees and
predominately south- or west-facing (Dorn 1990a, p. 8). These
conditions reduce percolation (water seeping into the ground) and
increase evaporation (Heidel 2009, p. 20). P. gibbensii has been
reported at elevations from 1,634 to 2,347 m (5,360 to 7,700 ft) (Dorn
1990a, p. 5; CNHP 2010a, unpaginated). Soils are typically highly
erodible, with low nutrient levels, low soil moisture, and high
selenium content (Spackman and Anderson 1999, p. 3).
Biological soil crusts are well-developed in Penstemon gibbensii
habitat in Colorado and Utah, but were not noted at any sites in
Wyoming (Heidel 2009, p. 14). Biological soil crusts are commonly found
in semiarid and arid environments such as the Great Basin and Colorado
Plateau, and are formed by a community of living organisms that can
include cyanobacteria, green algae, microfungi, mosses, liverworts, and
lichens (USGS 2006, unpaginated). These crusts provide many positive
benefits for the larger biotic community including decreased erosion,
improved water infiltration, increased seed germination, and improved
plant growth (Spackman and Anderson 1999, p 3; USGS 2006, p. 2).
Penstemon gibbensii exploits a largely barren, challenging
environment (Dorn 1990a, p. 3). This species is generally not tolerant
of competition from other species or other Penstemon plants; individual
plants are usually spaced one to several meters (3 or more ft) apart
(Dorn 1990a, pp. 8-9). Total vegetative cover is typically 5 to 10
percent (Fertig 2000, p. 2). Associated species include Elymus spicatus
(bluebunch wheatgrass), Achnatherum hymenoides (Indian ricegrass),
Herperostipa comata (needle-and-thread grass), Eriogonum brevicaule
(shortstem wild buckwheat), Eremogone hookeri (Hooker's sandwort), and
Minuartia nuttallii (Nuttall's stitchwort) (Heidel 2009, p. 13).
Adjacent vegetative communities may include pinyon-juniper woodlands,
sagebrush shrublands, or greasewood-saltbush shrublands (Dorn 1990a, p.
9).
Distribution
Penstemon gibbensii is a regional endemic, with a range that
includes Carbon and Sweetwater Counties in Wyoming, Moffat County in
Colorado, and Daggett County in Utah (Dorn 1990a, p. 6; Heidel 2009, p.
31). P. gibbensii was not recognized as a new species until 1981 (Dorn
1982, p. 334; Fertig and Neighbours 1996, pp. 4-6). Consequently, its
historical range is unknown. However, P. gibbensii was possibly always
uncommon (Heidel 2009, pp. 5, 8). The species is currently known from
nine occurrences including: Cherokee Basin, Sand Creek,
[[Page 33947]]
Flat Top Mountain, T84N R18W, Willow Creek, and Red Creek Rim in
Wyoming; Spitzie Draw and Sterling Place in Colorado; and Dagget
County, Utah. These nine occurrences are spread across 193 km (120 mi)
and occupy approximately 109 ha (270 ac) in Wyoming, 10 ha (25 ac) in
Colorado, and 2 ha (5 ac) in Utah (Heidel 2009, p. 31). Three of the
six Wyoming occurrences and the Colorado and Utah occurrences are
within 5 to 8 km (3 to 5 mi) of each other (Heidel 2009, p. 9). In
Wyoming, surveys for additional occurrences have been conducted in over
100 sections (each section is 259 ha (640 ac)), primarily along the
Carbon-Sweetwater County line (Heidel 2009, p. 12). Additional
potential habitat also has been searched in Moffat County, Colorado,
and in Daggett County, Utah; no new populations have been found in
these areas (Dorn 1990a, p. 6; Spackman and Anderson 1999, p. 31).
Most known Penstemon gibbensii (approximately 77 percent) occur on
State and Federal land. All Wyoming occurrences, with the exception of
the T84N R18W occurrence and a small portion of the Sand Creek
occurrence are on land managed by BLM (Heidel 2009, p. 27). The Nature
Conservancy (TNC) manages the T84N R18W occurrence, which is on State
and private land (Heidel 2009, p. 31). A small portion of the Sand
Creek occurrence also is on State land (Heidel 2009, p. 27). In
Colorado, the Spitzie Draw occurrence is on Browns Park National
Wildlife Refuge (NWR) (managed by the Service) and BLM land, and the
Sterling Place occurrence is on BLM land. The Daggett County, Utah,
occurrence is on State land (Heidel 2009, p. 27). Management
responsibilities are described in Table 2 below.
Abundance
Table 2 presents available information regarding the known
occurrences of Penstemon gibbensii. The plant numbers and occupied
habitat do not sum to the exact current total due to slight differences
between references. Most estimates are based on walking surveys through
occupied habitat; two sites (Cherokee Basin and Flat Top Mountain) also
have permanent transects for trend monitoring (Heidel 2009, Appendix
B).
Table 2--Known Occurrences of Penstemon Gibbensii
----------------------------------------------------------------------------------------------------------------
Estimated plant numbers
Species occurrence (year identified) (year surveyed) Occupied habitat Management
----------------------------------------------------------------------------------------------------------------
Cherokee Basin, WY (1981)............ 450 (1985)............. 6.2 ha (15.2 ac)....... BLM-Rawlins Field
Office.
1,400 (1988)
2,766 (1991)...........
1,000 (1995)...........
50-100 (2007)..........
Sand Creek, WY (1987)................ 2,000 (1989)........... 48.1 ha (118.7 ac)..... BLM-Rawlins Field
1,900-2,000 (1995)..... Office and State of
3,000 (2005)........... WY.
Flat Top Mountain, WY (1987)......... 300 (1989)............. 7.2 ha (17.9 ac)....... BLM-Rawlins Field
1,000-1,200 (1995)..... Office.
300 (2008).............
T84N R18W, WY (1997)................. 4,500-5,000 (1999)..... 28.8 ha (71.2 ac)...... TNC.
500-1,000 (2008).......
Willow Creek, WY (2004).............. 2,200 (2008)........... 15.6 ha (38.5 ac)...... BLM-Rawlins Field
Office.
Red Creek Rim, WY (2008)............. 120 (2008)............. 3.3 ha (8.1 ac)........ BLM-Rawlins Field
Office.
Spitzie Draw, CO (1982).............. 263 (2009)............. ~5 ha (12 ac).......... Service-Browns Park
NWR.
BLM-Little Snake Field
Office.
Sterling Place, CO (1984)............ 656 (2010)............. ~4 ha (9 ac)........... BLM-Little Snake Field
Office.
Daggett County, UT (1989)............ 300 (2010)............. 5 ha (12 ac)........... State of UT.
--------------------------------------------------
Current Total.................... ~11,000-14,000......... ~122 ha (300 ac)
----------------------------------------------------------------------------------------------------------------
Table 2 References: Heidel 2009, pp. 22, 31; CNHP in litt. 2009a, p. 2; in litt. 2009b, p. 2; in litt. 2010a, p.
2.
The Colorado Natural Heritage Program (CNHP) has designated
Penstemon gibbensii as a plant species of special concern (CNHP 2010b,
unpaginated). The WYNDD also has designated P. gibbensii as a plant
species of concern (Heidel 2007, p. 18). The Utah Native Plant Society
ranks P. gibbensii as a rare plant of ``extremely high priority'' (Utah
Rare Plants 2010, unpaginated). These designations are typically based
on TNC's natural heritage State rank. P. gibbensii is ranked S1 in all
three States because of its extreme rarity. These designations indicate
that particular consideration may be taken by the States with regard to
management decisions potentially affecting P. gibbensii, but do not
result in any regulatory protection for the species.
Trends
Long-term population trend data for Penstemon gibbensii is not
available. Short-term trends can be examined at four of the nine
occurrences, where population estimates are available for more than 1
year (see Table 1). Only a single population estimate is available from
the two most recently discovered sites in Wyoming and the three sites
in Colorado and Utah. Short-term trends for the three Wyoming
populations of P. gibbensii that have been surveyed more frequently
were described as stable to slightly increasing in 2000; this was
attributed to favorable climatic conditions in the preceding years
(Fertig 2000d, unpaginated). Since 2000, populations appear to be
stable to increasing at the Sand Creek occurrence and declining at the
other three Wyoming sites. Seedling establishment is probably episodic
(occurring at irregular intervals) and dependent on rare years of
adequate summer moisture (Fertig and Neighbours 1996, p. 16; Heidel
2009, p. 22). The resultant uneven survival of seedlings may account
for short-term population fluctuations in this species (Fertig and
Neighbours 1996, p. 16). Survey results from 1995 may represent peak
[[Page 33948]]
population estimates due to ideal climatic conditions, rather than mean
or low estimates (Heidel 2009, p. 23). Overall, there is not enough
information to conclusively determine rangewide trends for the species.
Five Factor Evaluation for Penstemon gibbensii
Information pertaining to Penstemon gibbensii in relation to the
five factors provided in section 4(a)(1) of the Act is discussed below.
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
The following potential factors that may affect the habitat or
range of Penstemon gibbensii are discussed in this section: (1) Energy
development, (2) roads, (3) trampling, (4) nonnative invasive plants,
and (5) climate change and drought.
Energy Development
As previously discussed, many activities associated with energy
development can destroy or modify habitat. Since 1989, energy
exploration has increased in the Wyoming portion of the range of
Penstemon gibbensii (Heidel 2009, p. 28). However, most occurrences of
P. gibbensii are on unstable slopes that are unlikely to be developed
for roads, pipelines, or well pads (Fertig and Neighbours 1996, pp. 19-
20; Heidel 2009, p. 28). However, the Sand Creek occurrence, which is
on flatter terrain, is located in an active oil and gas field, with one
pipeline passing through a subpopulation of P. gibbensii and an
accompanying access road intersecting a limited portion (does not
impact a lot of potential habitat of P. gibbensii) of another
subpopulation (Heidel 2009, p. 43). A well pad also is located nearby
(Heidel 2009, p. 28).
While this development has destroyed some P. gibbensii habitat,
some of the land disturbances at Sand Creek have provided additional
habitat by exposing appropriate substrate for plant establishment (Dorn
1990a, p. 13; Heidel 2009, p. 43). Two pipelines have been laid at the
Willow Creek occurrence, one adjacent to a subpopulation and the other
through a subpopulation that may have destroyed plants (Heidel 2009, p.
55). However, these developments dissect limited areas of occupied
habitat at Willow Creek, and the current impacts are likely not severe
as most of P. gibbensii is located on unstable slopes (Heidel 2009, p.
28). The sale of leases for oil and gas development continues in Carbon
and Sweetwater Counties in Wyoming (BLM 2010c, pp. 51-63, 75-77, 83).
Consequently, further energy development is possible within the
foreseeable future; however, potential impacts from it are unknown.
In addition to oil and gas development, uranium is mined near the
Red Creek Rim occurrence (Heidel 2009, p. 28). No impacts to Penstemon
gibbensii have been documented as a result of uranium mining. Sub-
bituminous coal underlies portions of the range of Penstemon gibbensii;
however, this coal is not suitable for strip mining (Heidel 2009, p.
28). Oil shale rock also is present (Heidel 2009, p. 28). Wind energy
development and gravel quarry development are possible, but have not
occurred to date (Heidel 2009, p. 28).
In conclusion, minimal impacts to Penstemon gibbensii were noted
from oil and gas development, no impacts have been documented from
uranium mining, and the other types of development are currently only
speculative. Therefore, we do not consider energy development to be a
threat to P. gibbensii now or in the foreseeable future.
Roads
Roads can destroy or modify habitat. Roads also can increase
access, leading to trampling or the introduction of nonnative invasive
plants (discussed below). A few roads cross or are adjacent to
occurrences of Penstemon gibbensii. As mentioned under energy
development, one access road intersects a limited portion of a
subpopulation at the Sand Creek occurrence, but also may provide
additional habitat as P. gibbensii is able to colonize the margins of
disturbed areas (Heidel 2009, pp. 28, 43). Another road crosses the
edge of the Willow Creek occurrence (Heidel 2009, p. 43). At the
Spitzie Draw occurrence, State Route 318 passes within 0.4 km (0.25
mi), and an access road passes within 200 m (656 ft) (Spackman and
Anderson 1999, p. 23). State Route 318 also passes within 50 m (164 ft)
of a portion of the Sterling Place occurrence (CNHP in litt. 2010a, p.
3). A steep road is adjacent to the Flat Top Mountain occurrence
(Fertig and Neighbours 1996, p. 35). The Flat Top Mountain road is
experiencing erosion that, if unchecked, could eventually encroach on
P. gibbensii occupied habitat (Fertig and Neighbours 1996, p. 35;
Heidel 2009, p. 59). We have no information on the building of future
roads, but do not anticipate any based on the topography and isolated
nature of most of P. gibbensii's distribution. Although some roads
occur in and near the habitat of P. gibbensii, we do not have any
indication that they have significant negative effects to the species.
Additionally, we have no information on dust or levels of travel on
these roads impacting P. gibbensii or its habitat.
In conclusion, only minimal impacts to Penstemon gibbensii were
noted from roads. Therefore, we do not consider roads to be a threat to
P. gibbensii now or in the foreseeable future.
Trampling
Trampling by livestock, ORVs, or human foot traffic can destroy
plants and increase soil erosion, especially at sites with steep, loose
soils. It has been mentioned as a potential concern at seven of nine
occurrences (Warren in litt. 1992, unpaginated; Fertig and Neighbours
1996, p. 20; Spackman and Anderson 1999, p. 31; Fertig 2000d,
unpaginated; Heidel 2009, p. 28; CNHP in litt. 2010a, p. 4). Penstemon
gibbensii may colonize the margins of disturbed areas, but cannot
become established within an area of active use (Heidel 2009, p. 28).
Soil disturbance has been noted at the Sterling Place occurrence from
cattle bedding down (CNHP in litt. 2010a, p. 4) and at the Cherokee
Basin occurrence from humans (Warren in litt. 1992, unpaginated).
Survey activities at Cherokee Basin in 1988 left distinct footprints
that were still distinguishable in places 3 years later (Warren in
litt. 1992, unpaginated).
As stated above, biological soil crusts have been noted at
occurrences in Colorado and Utah, but not in Wyoming (Spackman and
Anderson 1999, pp. 22, 26; Heidel 2009, pp. 14, 20; CNHP 2010a,
unpaginated; in litt. 2010d, p. 2). The absence of biological soil
crusts in Wyoming may reflect the effects of trampling from
historically heavy sheep (Ovis aries) grazing (Heidel 2009, p. 27).
In summary, trampling is a potential concern at most sites and has
been documented at two sites. However, we have no information regarding
whether any Penstemon gibbensii plants were actually trampled.
Additionally, P. gibbensii is able to colonize the margins of disturbed
habitats and is able to live in Wyoming where there is no evidence of
biological crusts in their habitat. We have no information indicating
that trampling is a threat to the species. Therefore, we do not
consider trampling to be a threat to P. gibbensii now or in the
foreseeable future.
Nonnative Invasive Plants
For general background information on nonnative invasive plants,
please refer to the first paragraph of ``Nonnative Invasive Plants''
under Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range in the Five Factor
[[Page 33949]]
Evaluation for Abronia ammophila section.
Encroachment of nonnative invasive plants may potentially impact
Penstemon gibbensii. However, P. gibbensii is typically restricted to
bare, sparsely vegetated slopes with large areas of exposed soil where
competition with other plant species, including nonnative invasive
species, is minimal (Heidel 2009, p. 26). Nonnative invasive plant
numbers are generally low in, and adjacent to, P. gibbensii
occurrences, and are most common near roads (Spackman and Anderson
1999, p. 23; Heidel 2009, p. 29). Alyssum desertorum (desert madwort)
has been documented at or near Cherokee Basin and Red Creek Rim; Bromus
tectorum, at or near Cherokee Basin, Red Creek Rim, Sand Creek,
Sterling Place, and Dagget County; Halogeton glomeratus (halogeton), at
or near Cherokee Basin, Red Creek Rim, Spitzie Draw, and Sterling
Place; and Salsola australis (Russian thistle), at or near Spitzie Draw
and Sterling Place (Heidel 2009, p. 29; CNHP 2010a, p. 2; in litt
2010d, p. 2). These species have been occasionally noted for at least
10 years (Spackman and Anderson 1999, pp. 23, 27; Heidel 2009, p. 29;
CNHP 2010a, unpaginated; CNHP 2010e, unpaginated), but there is no
evidence of increasing trends regarding their numbers at these sites.
There is no evidence that any of these nonnative invasive species have
had a negative impact on P. gibbensii.
Nonnative invasive plants are present at or near six occurrences of
Penstemon gibbensii. However, their numbers are generally low, and
there is no evidence that they are problematic. We have no information
indicating that nonnative invasive plants are a threat to the species.
Therefore, we do not consider nonnative invasive plants to be a threat
to P. gibbensii now or in the foreseeable future.
Climate Change and Drought
For general background information on climate change, please refer
to the first paragraphs of ``Climate Change'' under Factor A. The
Present or Threatened Destruction, Modification, or Curtailment of Its
Habitat or Range in the Five Factor Evaluation for Abronia ammophila
section.
Plant species with restricted ranges that also are climatically
limited may experience population declines as a result of climate
change (Schwartz and Brigham 2003, p. 11). Whether Penstemon gibbensii
would be positively impacted by an increase in barren land due to
drought that provided potential habitat, or negatively impacted by a
loss of current marginal habitat, cannot be predicted. Dorn (1990a, p.
6) noted that P. gibbensii has fewer and smaller flowers than most
species of Penstemon and hypothesized that this species may have once
grown under moister conditions and could be in long-term decline due to
climatic change. However, no additional supporting data were provided.
He also noted that populations at lower, hotter elevations are more
pubescent, a possible adaptation to conserve moisture (Dorn 1990a, p.
6).
Drought is a natural and common phenomenon within the range of
Penstemon gibbensii (Dorn 1990a, p. 6). Average annual precipitation
ranges from approximately 26 cm (10 in.) at Wyoming occurrences to
about 41 cm (16 in.) at Colorado and Utah occurrences (Heidel 2009, pp.
19-20). As discussed above, P. gibbensii appears to have minimal
reproductive success in most years because of dry conditions, but
responds favorably to late-summer moisture that occurs infrequently
(Fertig and Neighbours 1996, p. 16; Heidel 2009, p. 22). Penstemon
gibbensii is a warm-season plant that remains succulent through the
summer; therefore, it can take advantage of summer thunderstorms after
other species have stopped growing or completed their life cycle
(Warren in litt. 1992, unpaginated). Morphological adaptations
discussed above (pubescent, narrow leaves in hotter climes) also
indicate that the species is not limited by variations in the regional
climate to a great degree.
We believe that Penstemon gibbensii has evolved to adapt to
recurring drought conditions. Short-term population fluctuations, in
response to varying climatic conditions from year to year, appear to be
typical for the species. We have no information indicating that climate
change or drought is a threat to the species. Therefore, we do not
consider climate change or drought to be a threat to P. gibbensii now
or in the foreseeable future.
Summary of Factor A
Two occurrences (Sand Creek and Willow Creek) have experienced
minor impacts from energy development. Five occurrences (Sand Creek,
Willow Creek, Spitzie Draw, Sterling Place, and Flat Top Mountain) have
roads that are nearby or cross a portion of the occurrence. The Sand
Creek occurrence, which appears to be experiencing more disturbances
from energy development and road usage than the other sites, has had an
increase in P. gibbensii numbers according to survey results despite
these disturbances. We are not aware of any future energy development
projects being planned in or near any of the P. gibbensii occurrences.
Furthermore, the topography at most occurrences does not lend itself to
energy development or road construction (Fertig and Neighbours 1996,
pp. 19-20; Heidel 2009, p. 28). Therefore, we do not anticipate
substantial habitat disturbance in the future. Trampling has been
documented at two sites, but there is no information indicating that
plants have been destroyed. Nonnative invasive plants are present at or
near six occurrences of P. gibbensii. However, nonnative invasive plant
numbers are generally low, and there is no evidence that they are
problematic. Climate change and drought could potentially modify
habitat at all occurrences. However, the species appears to have
adapted to recurrent drought and variations in climatic conditions.
Adverse impacts due to habitat destruction, modification, or
curtailment appear minimal at the present time.
We conclude that the best scientific and commercial information
available indicates that Penstemon gibbensii is not in danger of
extinction or likely to become so within the foreseeable future because
of the present or threatened destruction, modification, or curtailment
of its habitat or range.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
We are not aware of any adverse impacts to Penstemon gibbensii from
overutilization for commercial, recreational, scientific, or
educational purposes at this time. We conclude that the best scientific
and commercial information available indicates that P. gibbensii is not
in danger of extinction or likely to become so within the foreseeable
future because of overutilization for commercial, recreational,
scientific, or educational purposes.
Factor C. Disease or Predation
Disease
We are not aware of any adverse impacts to Penstemon gibbensii from
disease at this time. Therefore, we do not consider disease to be a
threat to P. gibbensii now or in the foreseeable future.
Predation--Grazing and Herbivory
Penstemon gibbensii is relatively succulent and may be grazed by
mule deer (Odocoileus hemionus), pronghorn (Antilocapra americana),
domestic cattle (Bos taurus), and other herbivores
[[Page 33950]]
during late summer when green vegetation is sparse (Heidel 2009, p.
26). Currently, there is no sheep grazing in the habitat of P.
gibbensii (Fertig and Neighbours 1996, p. 19); as discussed above,
historical sheep use may have been heavy in Wyoming (Heidel 2009, p.
14). Grazing appears to be restricted almost entirely to flowering
stems, which could impact seed production, seed bank replenishment, and
long-term viability (Fertig and Neighbours 1996, p. 19). However, steep
slopes, unstable footing, and overall low forage production in P.
gibbensii habitat may limit use by wildlife and livestock (Warren in
litt. 1992, unpaginated; Heidel 2009, p. 27).
Grazing intensity often varies between years and between sites and
does not appear to negatively affect Penstemon gibbensii. At the
Spitzie Draw occurrence, variable levels of browsing by mule deer were
noted in 2009 (CNHP in litt. 2009a, unpaginated; in litt. 2009b,
unpaginated), but little evidence of grazing or browsing was found in
2010 (CNHP in litt. 2010c, p. 2). At the Sterling Place occurrence,
there was little evidence of damage to P. gibbensii from mule deer or
elk (Cervus canadensis), but there was moderate to heavy cattle grazing
(CNHP in litt. 2010a, p. 2). At the Daggett County occurrence, there
was little evidence of any grazing (CNHP in litt. 2010b, p. 2). P.
gibbensii numbers at Flat Top Mountain were high in 1995 and low in
2008 (see Table 2). However, plants experienced low levels of herbivory
(approximately 5 percent) in both years (Heidel 2009, p. 24). Cattle
grazing also was observed at the Sand Creek occurrence in 2005 (Heidel
2009, p. 43).
The Cherokee Basin occurrence is the only site that is fenced. In
1985, the BLM fenced 95 percent of the site to exclude cattle, and 5
percent or less was left unfenced (Warren in litt. 1992, unpaginated).
The allotment, an area larger than the P. gibbensii occurrence, was
monitored to compare the effects of grazing pressure (Warren in litt.
1992, unpaginated). In 1992, the overall level of livestock use in the
allotment was low to moderate, the range was in good to excellent
condition with an improving trend, and a reduced stocking rate was not
recommended (Warren in litt. 1992, unpaginated). The Cherokee Basin
exclosure has been critical in ruling out grazing as the cause of
recent declines at this occurrence, where plant numbers have declined
since the early 1990s (see Table 1) (Heidel 2009, p. 30).
No specific information regarding grazing is available for the T84N
R18W, Willow Creek, or Red Creek Rim occurrences, other than general
observations regarding the potential for grazing by livestock and
wildlife.
Grazing intensity is variable between years and sites, but appears
to have minimal impact to Penstemon gibbensii, possibly because of
steep slopes, unstable footing, and overall low forage production in
the species' habitat. Fluctuations in plant numbers have occurred at
Flat Top Mountain, despite consistent levels of grazing, and at
Cherokee Basin, in the absence of grazing, which supports the
conclusion that grazing causes minimal adverse impacts to P. gibbensii.
Therefore, we do not consider grazing to be a threat to P. gibbensii
now or in the foreseeable future.
Summary of Factor C
We have no evidence of adverse impacts to Penstemon gibbensii from
disease. P. gibbensii is relatively succulent and may be grazed by both
wildlife and livestock, particularly in late summer when most sympatric
vegetation has dried. However, the typical habitat of P. gibbensii
(steep slopes, loose substrate, and sparse vegetative cover) appears to
limit heavy grazing at most sites and minimize impacts from grazing.
We conclude that the best scientific and commercial information
available indicates that Penstemon gibbensii is not in danger of
extinction or likely to become so within the foreseeable future because
of disease or predation.
Factor D. The Inadequacy of Existing Regulatory Mechanisms
The Act requires us to examine the adequacy of existing regulatory
mechanisms with respect to threats that may place Penstemon gibbensii
in danger of extinction or likely to become so in the future. Existing
regulatory mechanisms that could have an effect on potential threats to
P. gibbensii include (1) Federal laws and regulations; (2) State laws
and regulations; and (3) local land use laws, processes, and
ordinances. Actions adopted by local groups, States, or Federal
entities that are discretionary, including conservation strategies and
guidance, are not regulatory mechanisms; however, we may discuss them
in relation to their effects on potential threats to the species.
Federal Laws and Regulations
Bureau of Land Management
Most known Penstemon gibbensii occurrences are on BLM land (see
Table 2). The BLM recognizes P. gibbensii as a sensitive species
throughout its range (Heidel 2009, p. 6). Sensitive species designation
requires that the species is: (1) Native, (2) at risk or populations
trending downward throughout all or a significant portion of its range,
and (3) dependent on special or unique habitat on BLM lands (Sierra
2009, in litt.). As discussed above, these species are managed to
promote their conservation and minimize the likelihood and need for
listing under the Act. The oldest known occurrence at Cherokee Basin
was fenced by the BLM for added protection (see Factor C). Four
occurrences (Cherokee Basin, Flat Top Mountain, Spitzie Draw, and
Sterling Place) were recommended by the BLM for designation as ACECs
(Heidel 2009, pp. 30-31). However, the final records of decision for
the Rawlins RMP in Wyoming and the Little Snake River RMP in Colorado
did not designate any of these occurrences as ACECs (Heidel 2009, pp.
30-31). Designation as an ACEC would have protected these sites from
surface disturbances associated with energy and road development.
Nevertheless, as discussed under Factor A, additional energy
development is not anticipated, and the steep slopes found at these
sites render them ill-suited for most road construction.
National Wildlife Refuge
Browns Park National Wildlife Refuge maintains a variety of native
habitats and wildlife, with emphasis on migratory birds, threatened and
endangered species, and species of special concern. The NWR has a
portion of one occurrence of Penstemon gibbensii, which is protected by
refuge regulations that require all vehicles to remain on developed
roads and prohibit the collection, possession, or destruction of any
plant (Service 2010, unpaginated).
National Environmental Policy Act
Most known Penstemon gibbensii (approximately 77 percent) occur on
Federal and State land (Heidel 2009, pp. 22, 27). All Federal agencies
are required to adhere to the NEPA for projects they fund, authorize,
or carry out. Please refer to the NEPA discussion under Factor D. The
Inadequacy of Existing Regulatory Mechanisms in the Five Factor
Evaluation for Abronia ammophila section for additional information.
State Regulatory Mechanisms
The Penstemon gibbensii occurrence in Daggett County, Utah, and a
portion of the T84N R18W, Wyoming occurrence are on State lands. P.
gibbensii is designated as a rare plant in Utah and a species of
concern in Wyoming (WNDD 2007, p. 2; Utah Rare Plants 2010, p. 2).
These designations
[[Page 33951]]
signify recognition by the States regarding the rarity of the species,
but do not confer any specific protection.
Local Land Use Laws, Ordinances, and Contracts
The Nature Conservancy
TNC has a conservation easement on the private land portion of the
T84N R18W occurrence that protects the area from many development
activities (Heidel 2009, p. 31). This is a permanent easement that
includes surface rights, but not mineral rights (Browning 2010, pers.
comm.).
Summary of Factor D
We have no evidence of impacts to Penstemon gibbensii from
inadequate regulatory mechanisms. All but a portion of one occurrence
are on Federal or State lands. The portion on private land is largely
protected by a conservation easement. Seven of the nine known
occurrences are managed all or in part by BLM, which promotes the
conservation of sensitive species and minimizes the likelihood and need
for their listing under the Act. The Service has refuge regulations
that protect P. gibbensii occurring on their lands.
We conclude that the best scientific and commercial information
available indicates that Penstemon gibbensii is not in danger of
extinction or likely to become so within the foreseeable future because
of inadequate regulatory mechanisms.
Factor E. Other Natural or Manmade Factors Affecting Its Continued
Existence
Natural and manmade factors with the potential to affect Penstemon
gibbensii include: (1) Small population size, (2) pollination, and (3)
genetic diversity.
Small Population Size
For general background information on small population size, please
refer to the first paragraph of ``Small Population Size'' under Factor
E. Other Natural or Manmade Factors Affecting Its Continued Existence
in the Five Factor Evaluation for Abronia ammophila section.
No information exists regarding the historical range or population
numbers of Penstemon gibbensii, but experts familiar with the species
conclude that it was likely historically rare (Dorn 1990a, p. 6; Fertig
and Neighbours 1996, p. 4; Spackman and Anderson 1999, p. 32; Heidel
2009, p. 5). P. gibbensii is a local endemic that has evolved to
exploit a barren, erodible habitat (Dorn 1990a, p. 3). The slight
morphological differences, different substrates, and widely separated
distribution suggest that the species is a paleoendemic (has been in
existence for a long period of time in a single region) (Dorn 1990a, p.
6; Heidel 2009, p. 5). Detailed descriptions of the species' abundance
and trends are provided under the Abundance and Trends sections for
this species. No occurrences have been extirpated since the species was
first identified in 1981, indicating some resilience to perturbation.
New occurrences of Penstemon gibbensii continue to be documented
including Willow Creek in 2004 and Red Creek Rim in 2008 (Heidel 2009,
p. 9). P. gibbensii is presently known from nine occurrences that span
a distance of 193 km (120 mi) (Heidel 2009, p. 31). Some potentially
suitable areas have not yet been surveyed (Heidel 2009, pp. 10-12), and
more occurrences may be located.
Penstemon gibbensii is likely a historically rare plant that has
nonetheless persisted. Existing sites are monitored, and surveys have
located new occurrences. No occurrences have been extirpated. We have
no information indicating that random demographic or environmental
events are a threat to the species because of its small population
size. Therefore, we do not consider small population size to be a
threat to P. gibbensii now or in the foreseeable future.
Pollination
Penstemons are pollinated by a variety of insects and hummingbirds,
but most commonly by insects from the Order Hymenoptera (Wolfe et al.
2006, pp. 1699, 1709). Bees have been seen visiting flowers at sites in
Colorado and Utah (Langton 2010, pers. comm.). As discussed above,
pollinators may regard small populations as inferior or unreliable food
sources, leading to low visitation rates (Oostermeijer 2003, p. 23).
Low visitation rates may be more of a concern in currently rare species
that were historically abundant (Brigham 2003, p. 84). However, as
identified above, Penstemon gibbensii is believed to have been
historically rare (Dorn 1990a, p. 6; Fertig and Neighbours 1996, p. 4;
Spackman and Anderson 1999, p. 32; Heidel 2009, p. 5).
Only very limited information is available regarding pollination of
Penstemon gibbensii. However, we have no information indicating that
poor pollination is a threat to the species. Therefore, we do not
consider lack of pollinators to be a threat to P. gibbensii now or in
the foreseeable future.
Genetic Diversity
For general background information on genetic diversity, please
refer to the first paragraph of ``Genetic Diversity'' under Factor E.
Other Natural or Manmade Factors Affecting Its Continued Existence in
the Five Factor Evaluation for Abronia ammophila section.
The risk of negative consequences to rare plants from reduced
genetic diversity varies (Brigham 2003, p. 88). Penstemon gibbensii is
one of several plant species being studied in a comparative population
genetics analysis. Initial results from a study of two Wyoming
populations document high variation of DNA sequences within populations
examined to date; however, between-population differentiation analysis
has not yet been conducted (Heidel 2009, p. 5). These results are
preliminary and limited in scope, but indicate that an adequate level
of genetic diversity exists in these populations. Genetic exchange
could be possible as three of the Wyoming occurrences and the three
occurrences in Colorado and Utah are within 5 to 8 km (3 to 5 mi) of
each other (Heidel 2009, p. 9).
Only very limited information regarding the genetic diversity
exhibited by Penstemon gibbensii is available. However, we have no
information indicating that a lack of genetic diversity is a threat to
the species. Therefore, we do not consider reduced genetic diversity to
be a threat to P. gibbensii now or in the foreseeable future.
Summary of Factor E
We conclude that the best scientific and commercial information
available indicates that Penstemon gibbensii is not in danger of
extinction or likely to become so within the foreseeable future because
of small population size, reduced pollination, or reduced genetic
diversity.
Finding
As required by the Act, we considered the five factors in assessing
whether Penstemon gibbensii is threatened or endangered throughout all
of its range. We examined the best scientific and commercial
information available regarding the past, present, and future threats
faced by the species. We reviewed the petition, information available
in our files, other available published and unpublished information,
and we consulted other Federal and State agencies.
Five occurrences (Sand Creek, Willow Creek, Spitzie Draw, Sterling
Place, and
[[Page 33952]]
Flat Top Mountain) have experienced some minimal adverse impacts to the
habitat of Penstemon gibbensii due to oil and gas development and road
construction. The topography at most occurrences does not lend itself
to energy development or road construction; therefore, we do not
anticipate substantial habitat disturbance in the future. All
occurrences could experience increased temperatures and precipitation
changes from climate change. Whether this would result in a net gain or
net loss in potential habitat cannot be predicted. However, differing
morphological adaptations at the various occurrences indicate that the
species can adapt to variable climate conditions.
Five occurrences (Sand Creek, Flat Top Mountain, Spitzie Draw,
Sterling Place, and Daggett County) have documentation of grazing.
However, the typical habitat of P. gibbensii (steep slopes, loose
substrate, and sparse vegetative cover) appears to limit heavy grazing.
Two occurrences (Cherokee Basin and Sterling Place) have experienced
some trampling by humans and livestock. However, we are not aware of
any loss of P. gibbensii at either of these sites from trampling.
All occurrences experience drought as a natural and regular
phenomenon, which likely results in short-term population fluctuations.
However, P. gibbensii has evolved to adapt to recurring drought
conditions. Six occurrences (Cherokee Basin, Sand Creek, Red Creek Rim,
Spitzie Draw, Sterling Place, and Daggett County) have nonnative
invasive plants at or near the site. However, the typical habitat of P.
gibbensii is sparsely vegetated slopes with large areas of bare soil
where competition with other plant species, including nonnative
invasive plants, is minimal.
All occurrences have relatively small populations. However, P.
gibbensii is considered historically rare. No occurrences have been
extirpated since the species was first identified, and new occurrences
continue to be documented. We have no information regarding actual or
potential adverse impacts due to overutilization, disease, inadequate
regulatory mechanisms, reduced genetic diversity, or reduced
pollination.
Based on our review of the best available scientific and commercial
information pertaining to the five factors, we find that the threats
are not of sufficient imminence, intensity, or magnitude to indicate
that Penstemon gibbensii is in danger of extinction (endangered), or
likely to become endangered within the foreseeable future (threatened),
throughout all of its range. Therefore, we find that listing P.
gibbensii as a threatened or endangered species is not warranted
throughout all of its range.
Significant Portion of the Range
Having determined that Penstemon gibbensii does not meet the
definition of a threatened or endangered species, we must next consider
whether there are any significant portions of the range where P.
gibbensii is in danger of extinction or is likely to become endangered
in the foreseeable future.
In determining whether Penstemon gibbensii is threatened or
endangered in a significant portion of its range, we first addressed
whether any portions of the range of P. gibbensii warrant further
consideration. We evaluated the current range of P. gibbensii to
determine if there is any apparent geographic concentration of the
primary stressors potentially affecting the species including energy
development, roads, climate change, grazing, trampling, drought,
nonnative invasive plants, and small population size. P. gibbensii is
likely a historically rare endemic plant known from nine occurrences
spanning a distance of 193 km (120 mi) (Heidel 2009, p. 31). This
species' small range suggests that stressors are likely to affect it in
a uniform manner throughout its range. All stressors occur at or near
most sites, with the exception of energy development, which has been
documented at or near three occurrences. However, the sale of oil and
gas leases is ongoing; consequently, it is a potential stressor at most
sites. Effects to P. gibbensii from these stressors are not
disproportionate in any portion of the species' range. As we explained
in detail in our analysis of the status of the species, none of the
stressors faced by the species are sufficient to place it in danger of
extinction now (endangered) or in the foreseeable future (threatened).
Therefore, no portion is likely to warrant further consideration, and a
determination of significance is not necessary.
We do not find that Penstemon gibbensii is in danger of extinction
now, nor is it likely to become endangered within the foreseeable
future throughout all or a significant portion of its range. Therefore,
listing P. gibbensii as threatened or endangered under the Act is not
warranted at this time.
We request that you submit any new information concerning the
status of, or threats to, Penstemon gibbensii to our Wyoming Ecological
Services Field Office (see ADDRESSES section) whenever it becomes
available. New information will help us monitor P. gibbensii and
encourage its conservation. If an emergency situation develops for P.
gibbensii, or any other species, we will act to provide immediate
protection.
Species Information for Boechera pusilla
Species Description
Boechera pusilla (Fremont County rockcress or small rockcress) is a
perennial herb with several decumbent (lying down), unusually slender
stems up to 17 cm (6.7 in.) long. The plant has basal leaves that are
linear (at least 10 times longer than wide) and erect, with relatively
sparse forked spreading hairs located on the leaves. Plants generally
have three to five stem leaves that are nonclasping (not encircling the
stem) and widely spaced. Flowers are small, light lavender, four-
petaled, and blossom from May to mid-June. The fruits, which are
present from mid-June to July, are hairless linear siliques (narrow
elongated seed capsule) that spread at right angles from the drooping
main stem on pedicels (small stalks) less than 3 mm (0.12 in.)
(Marriott 1986, p. 3; Dorn 1990b, pp. 2-3; Fertig 1994, unpaginated;
Heidel 2005, p. 3).
Discovery and Taxonomy
Boechera pusilla was first collected near South Pass in Fremont
County, Wyoming, in 1981 (Dorn 1990b, p. 1). B. pusilla is a member of
the Brassicaceae (mustard) family and was formerly classified as Arabis
pusilla (Fertig 1994, unpaginated), which was the name used in the
petition (Forest Guardians 2007, p. 23). However, studies in 2003
suggest that most North American Arabis species should be placed in the
Boechera genus (Al-Shehbaz 2003, entire). This determination was based
on their distinct chromosome numbers and on molecular data indicating
that American and Eurasian species that were classified as Arabis have
more dissimilarities between them than they do with many other widely
recognized genera in the mustard family (Al-Shehbaz 2003, pp. 382-383).
Although some botanists do not fully support the change (Murray and
Elven 2009, unpaginated), reclassification to the Boechera genus has
been widely accepted (Holmgren et al. 2005, p. 537; Flora of North
America 2010b, unpaginated). For the purposes of this finding, we
primarily refer to the species as Boechera pusilla, but consider Arabis
pusilla to be the same species.
Boechera pusilla is genetically closely related to Boechera demissa
var. languida (nodding rockcress), Boechera
[[Page 33953]]
pendulina var. russeola (Daggett rockcress), and Boechera oxylobula
(Glenwood Springs rockcress) and occurs in a similar geographic area as
B. demissa var. languida and B. pendulina var. russeola (Dorn 1990b, p.
5; Heidel 2005, p. 2). Five additional species of rockcress occur in or
near B. pusilla habitat, representing a high amount of diversity within
the genus (Heidel 2005, p. 2). B. pusilla requires a highly specialized
habitat (discussed below under Habitat) that is newly formed, which
suggests the species is relatively recently derived from a common
ancestor (Dorn 1990b, p. 5). Based on morphological evidence, B.
pusilla may be a hybrid of B. pendulina and B. lemmonii (Lemmon's
rockcress) (Flora of North America 2010b, unpaginated). We recognize B.
pusilla as a valid species and a listable entity.
Biology and Life History
Due to the short growing season (approximately 30 days) in the
areas that Boechera pusilla occupies, the plant only flowers in May and
June with fruits maturing several weeks later (Dorn 1990b, p. 9; Fertig
1994, unpaginated; Heidel 2005, pp. 3, 15). Fruits are only evident
during the short frost-free period during the middle of summer
(primarily July) and shatter thereafter (Heidel 2005, p. 15). Remnant
flower stalks persist through the winter and into the next flowering
season (Heidel 2005, p. 15).
Not all plants produce fruit in a particular year (Heidel 2005, pp.
15-16), which is thought to be caused by freezing conditions in spring
or possibly drought (Heidel 2005, pp. 15-16). All Boechera pusilla
reproduction is apparently by seed (Dorn 1990b, p. 9; Heidel 2005, p.
15), and the species is apomictic (i.e., reproduces by seed with no
fertilization, resulting in offspring that are essentially clones)
(Flora of North America 2010b, unpaginated). However, similar Boechera
species have variation in the amount of sexual and asexual reproduction
(Roy 1995, pp. 874-876), and we are unsure whether B. pusilla exhibits
a mixed-mating system. We do not have information about how long the
species' seeds remain viable or under what conditions they germinate.
Apomictic species within the Boechera genus result from hybridization
of sexual Boechera species (Flora of North America 2010b, unpaginated).
Reproduction of B. pusilla is by (nonwinged) seeds that likely drop
near the parent plant, with some seeds dispersed via wind or water
(Dorn 1990b, p. 9). It has relatively few seeds per fruit compared to
some other Boechera species (Dorn 1990b, p. 9). Dispersal vector
information is unknown at this time (Heidel 2005, p. 15).
Habitat
Boechera pusilla occupies sparsely vegetated, coarse granite soil
pockets in exposed granite-pegmatite outcrops, with slopes generally
less than 10 degrees, at an elevation between 2,438 to 2,469 m (8,000
to 8,100 ft) (Dorn 1990b, pp. 3, 6). A pegmatite is a very coarse-
grained igneous (formed from magma or lava) rock that usually occurs in
dikes (sheet-like body of magma) (Heidel 2005, p. 8). The soils are
sandy to loamy (mixture of clay, silt and sand), poorly developed, very
shallow, and possibly subirrigated by runoff from the adjacent exposed
bedrock (solid consolidated rock) (Dorn 1990b, pp. 6-8). B. pusilla is
likely restricted in distribution by the limited occurrence of
pegmatite in the area (Heidel 2005, p. 8). A distribution model shows
potential habitat could occur in an area no greater than two townships
(186.5 km\2\; 72 mi\2\) (Heidel 2005, p. 7). The dense nature of
pegmatite does not allow for fertile soil, therefore restricting
vegetation growth (Heidel 2005, p. 15). The specialized habitat
requirements of B. pusilla have allowed the plant to persist without
competition from other herbaceous plants or sagebrush-grassland species
that are present in the surrounding landscape (Dorn 1990b, pp. 6, 8).
Although the surrounding vegetation is sparse (less than 10 percent
cover), Boechera pusilla is associated with numerous mat-forming
perennial herbs (e.g., Erigeron caespitosus (tufted fleabane)),
perennial grasses (e.g., Achnatherum hymenoides (Indian ricegrass)),
and shrubs (e.g., Artemesia arbuscula (dwarf sagebrush)) (Heidel 2005,
p. 9). Rolling hills with a gradual sloping impediment are the
predominant landscape features in the area, which is a transition zone
between the montane conifer forests and the high sagebrush desert
(Heidel 2005, pp. 8-9). The adjacent vegetation consists primarily of
sagebrush-grassland or open Pinus flexilis (limber pine) habitat (Dorn
1990b, p. 8).
Annual precipitation in the area averages 30.5 cm (12 in.), with
the majority falling in the form of winter snow (Marriott 1986, p. 9).
Average minimum and maximum temperatures in this area range between -
16.1 and -3.9 [deg]C (3 and 25 [deg]F) in January and 4.6 and 24.4
[deg]C (42 and 76 [deg]F) in July (Dorn 1990b, p. 6), with strong,
frequent winds present year-round (Heidel 2005, p. 10). This area has a
very short growing season; approximately 30 frost-free days occur
between mid-June and mid-July (Marriott 1986, p. 9). Boechera pusilla
may be adapted to wide fluctuations in available moisture as the soil
goes through cycles of rapid drying and saturation (Dorn 1990b, p. 6).
Distribution and Abundance
The distribution of Boechera pusilla is extremely limited due to
its very specific habitat requirements (Dorn 1990b, p. 8). The only
known population of B. pusilla is located on lands administered by the
BLM Rock Springs Field Office in the southern foothills of the Wind
River Range (Fertig 2000a, p. 39; Heidel 2005, pp. ii, 6). The species'
range is approximately 64.8 ha (160 ac), with occupied habitat
estimates ranging from 2.4 to 6.5 ha (6 to 16 ac) (Dorn 1990b, p. 8;
Heidel 2005, p. 15). Botanists have surveyed for B. pusilla
systematically in other areas and discovered no additional populations,
but some areas with potential habitat have not been surveyed (Marriott
1986, p. 8; Heidel 2005, p. 6).
To explain the trend of Boechera pusilla numbers, we use the
estimates of total flowering plants in the entire population (i.e.,
total for the species) and the total flowering plants in a plot located
in the largest subpopulation. These two indicators are the most
consistently documented information we could find. The number of
flowering plants is used, at least in part, to ensure identification of
the species (Heidel 2010d, pers. comm.). In 1988, the total population
estimate was 800 to 1,000 flowering individuals (Heidel 2005, p. 14).
This was an increase from the 50 plants found in 1986; however, only 1
subpopulation was discovered that year (Marriott 1986, p. 15). In 1990,
numbers were down to about 600 flowering plants for the entire
population (Dorn 1990b, p. 8). Although the 1988 survey indicated no
evidence that B. pusilla was affected by the 1988 drought (Marriott and
Horning in litt. 1988, p. B2), drought impacts, such as reduced seed
fecundity or germination, may not be immediately apparent (Heidel
2010c, pers. comm.; 2010d, pers. comm.). The decrease to 600 flowering
plants documented in 1990 may be due to a pattern of short-term decline
under drought conditions that occurred in this area between 1988 and
1990 (Heidel 2005, p. 14).
In 2003, WYNDD estimated total flowering plants for the entire
population at 150 to 250 (Heidel 2005, p. 14). The mean density of
flowering plants derived from the 1988 and 2003 surveys indicate that
the density dropped from 1.68 down to 0.33 flowering plants per m\2\
(0.156 down to 0.031 flowering plants per ft\2\) during
[[Page 33954]]
this 15-year period (Heidel 2005, p. 14). Declines in 2003 may be
attributed to severe drought conditions recorded in the Wind River
Range between 2000 and 2003 (NOAA 2005 as cited in Heidel 2005, p. 14).
Flowering plants for the entire population in 2010 were estimated at
approximately 350 individuals (Heidel 2010d, pers. comm.).
The subpopulation plot, where the largest number of plants is
found, had 671 individual flowering Boechera pusilla plants in 1988
(Heidel 2005, p. 14). This area had 87 flowering plants when it was
counted again in 2003 (Heidel 2005, p. 14). In 2010, the plot had 56
flowering plants (Heidel 2010c, pers. comm.). Flowering plant numbers
in the subpopulation plot has consistently declined. However, numbers
of flowering plants for the entire subpopulation where the plot is
located increased from between 100 and 150 in 2003 (Heidel 2005, p. 14)
to 283 in 2010 (Heidel 2010c, pers. comm.). The decrease of plants in
the plot but increase in the subpopulation over this period suggests
the distribution of the subpopulation shifted over that period of time
(Heidel 2010c, pers. comm.).
Boechera pusilla has at least eight subpopulations (Amidon 1994, in
litt., unpaginated), the largest of which has been surveyed
periodically as described above (Heidel 2005, p. 14; Heidel 2010c,
pers. comm.). Additional subpopulations are small; in 2003, 1
subpopulation had 30 to 50 flowering plants, another had 10 to 15
flowering plants, and 5 of the subpopulations had less than 5 flowering
plants each (Heidel 2005, p. 14).
Based on a limited number of surveys, the plant appears to have an
overall pattern of decline documented since estimates were first
provided in 1988 (Heidel 2005, p. 17; Heidel 2010c, pers. comm.;
Windham 2010, pers. comm.). Boechera pusilla numbers increased in 2010
compared to 2003, but the overall trend is downward, with 2010
population numbers at 350 compared to 800 to 1000 in 1988.
Reproductive success may vary considerably from year to year
depending on climate conditions, leading to wide fluctuations in
populations (Dorn 1990b, p. 10). Possible evidence of these
fluctuations is low levels of fruit production in 2003 that visibly
increased in 2010 (Heidel 2010c, pers. comm.). However, 2010 plant
numbers are low compared to those documented in 1988 and 1990.
Five Factor Evaluation for Boechera pusilla
Information pertaining to Boechera pusilla in relation to the five
factors provided in section 4(a)(1) of the Act is discussed below.
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
The following potential factors that may affect the habitat or
range of Boechera pusilla are discussed in this section: (1)
Recreational activities, (2) energy development, (3) nonnative invasive
plants, (4) climate change, and (5) drought.
Recreational Activities
Boechera pusilla's current known range is highly restricted. All
known occurrences are on BLM land, which is public land managed for
multiple use (Dorn, 1990, p. 10; Heidel 2005, p. 6). Prior to the
development of a Habitat Management Plan (BLM 1994, entire) and the
closure of vehicle access in 1994 (59 FR 37258), B. pusilla was more
readily exposed to recreation activity from ORV use associated with
fishing and camping, unauthorized ORV use, horse boarding and feeding,
plant collecting, mountain biking and pedestrian use. In addition, a
nearby quarry, that is now inactive, may have destroyed potential
habitat (Dorn 1990b, p. 11; Heidel 2005, p. 17). Previously, ORV use
has been identified as a potential threat; however, conservation
measures, such as the habitat management plan, have been implemented to
eliminate this threat. Currently, the only access to the area occupied
by B. pusilla is by foot, but due to the rocky substrate associated
with the habitat, recreational use in the area primarily occurs on
adjacent riparian areas, away from occupied habitat (Dana 2010a, pers.
comm.). Therefore, recreational activities are not considered a threat
now or in the foreseeable future.
Energy Development
The extraction of natural gas occurs in several developments in
southwest Wyoming, which could be a potential threat to the habitat of
Boechera pusilla (USGS 2010, p. 3). However, the area occupied by B.
pusilla is incorporated into a Special Recreation Management Area
(SRMA), which is closed to mineral and energy development (BLM 1997,
pp. 17-18). Currently the nearest gas development occurs approximately
10.1 km (6.3 mi) from the location of B. pusilla (Kile 2010, pers.
comm.) and does not appear to be a threat to the plant.
In addition, on February 23, 1998, the Secretary of the Interior
issued Public Land Order No. 7312, the Withdrawal of Public Land for
the Protection of Arabis Pusilla Plant Habitat. This order pursuant to
Section 204 of the Federal Land Policy and Management Act of 1976, 43
U.S.C. 1714 (1994), withdrew from ``settlement, sale, location, or
entry under the general land laws, including the United States mining
laws (30 U.S.C. Ch. 2 (1994)), but not from leasing under the mineral
leasing laws'' on 412.8 ha (1,020 ac) to protect Boechera pusilla
habitat (63 FR 9012). This withdrawal expires in 50 years (2048) unless
the Secretary determines that the withdrawal shall be extended.
Therefore, we do not consider energy development to be a threat to B.
pusilla now or in the foreseeable future.
Nonnative Invasive Plants
For general background information on nonnative invasive plants,
please refer to the first paragraph of ``Nonnative Invasive Plants''
under Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range in the Five Factor Evaluation for
Abronia ammophila section.
The habitat adjacent to the area occupied by Boechera pusilla is
primarily sagebrush steppe, which is highly vulnerable to nonnative
invasive species (Anderson and Inouye 2001, pp. 531-532); however,
surveys conducted by WNDD in 2003 found the area generally free of
nonnative invasive species (Heidel 2005, p. 10). As noted previously,
the restrictive habitat occupied by B. pusilla may limit the potential
for competition from other herbaceous plants (Dorn 1990b, pp. 6, 8). We
have no information that nonnative invasive plants are a threat to B.
pusilla. Therefore, we do not consider nonnative invasive plants to be
a threat to B. pusilla now or in the foreseeable future.
Climate Change
For general background information on climate change, please refer
to the first paragraphs of ``Climate Change'' under Factor A. The
Present or Threatened Destruction, Modification, or Curtailment of Its
Habitat or Range in the Five Factor Evaluation for Abronia ammophila
section.
Plant species with restricted ranges may experience population
declines as a result of climate change. The habitat for Boechera
pusilla appears to be exposed to variation in moisture, and B. pusilla
may be adapted to some variation in moisture availability (Dorn 1990b,
p. 6). Climate change has the
[[Page 33955]]
potential to affect the species' habitat, but we lack scientific
information on what those changes may ultimately mean for B. pusilla.
Climate change may affect the timing and amount of precipitation as
well as other factors linked to habitat conditions for this species.
However, at this time the available scientific information does not
indicate that climate change is likely to threaten the species.
Therefore, we do not consider climate change to be a threat to B.
pusilla now or in the foreseeable future.
Drought
Limited evidence shows there may be some response of Boechera
pusilla to drought conditions, but those effects may be delayed (Heidel
2010c, pers. comm.). As discussed above, a 1988 survey, conducted
during a drought year, found increased abundance of plants from 1986
(Marriott and Horning in litt. 1988, p. B2), but surveys conducted in
1990 found reduced numbers (Dorn 1990b, p. 8) that may have been caused
by continued drought conditions (Heidel 2005, p. 14). Reproductive
success may vary considerably from year to year depending on climate
conditions, leading to wide fluctuations in populations (Dorn 1990b, p.
10). Overall reductions in population size since 1988 may be linked to
periods of drought conditions that have occurred between 1988 and 2010,
but B. pusilla monitoring efforts are not sufficient during this period
to understand the role of drought in population decline. Therefore,
because of lack of evidence, we do not consider drought to be a threat
to B. pusilla now or in the foreseeable future.
Summary of Factor A
In summary, we found that numerous management actions taken
previously by the BLM alleviated several potential threats to Boechera
pusilla and its habitat. These potential threats included ORV use,
heavy foot traffic, and mining. The ORV use and mining are no longer
permitted in the area due to the implementation of numerous regulatory
mechanisms (see Factor D. Inadequacy of existing regulatory mechanisms
below) in addition to the construction of an exclosure. We have no
information that nonnative invasive plants are a threat to the species.
Other activities in the area, such as limited foot traffic, are not
considered threats. Although climate change may be a potential long-
term stressor to B. pusilla, the limited information available
regarding climate change impacts on B. pusilla and the species'
adaptations to an already-variable climate do not suggest that climate
change currently, or in the foreseeable future, will threaten this
species' existence. We do not fully understand the response of B.
pusilla to drought conditions, but limited evidence indicates that
drought may be contributing to this species' reduced population size
(see Factor E. Other Natural Or Manmade Factors Affecting Its Continued
Existence discussion below). However, we do not have sufficient
information to say that drought alone, or in combination with other
factors, threatens the species currently or is likely to do so in the
foreseeable future.
We conclude that the best scientific and commercial information
available indicates that Boechera pusilla is not in danger of
extinction or likely to become so within the foreseeable future because
of the present or threatened destruction, modification, or curtailment
of its habitat or range.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Field notes from 1993 suggest that some Boechera pusilla seed had
been collected and sent to the DBG; however, they do not have a record
of receiving any B. pusilla seeds (Neale 2010b, pers. comm.). Some
specimens collected in the 1980s were provided to the Gray Herbarium of
Harvard University, the New York Botanical Garden, and the Rocky
Mountain Herbarium at the University of Wyoming (Dorn 1990b, p. 5, 14).
We have no other indication that any collections or utilization have
been made of B. pusilla. Therefore, we find that B. pusilla is not in
danger of extinction or likely to become so within the foreseeable
future because of overutilization for commercial, recreational,
scientific, or educational purposes.
Factor C. Disease or Predation
Disease
Boechera pusilla is not specifically known to be affected or
threatened by any disease. Systemic rust disease is known to affect
many Boechera species (Ladyman 2005, p. 26), but we have no information
that it is found in B. pusilla. Therefore, we do not consider disease
to be a threat to B. pusilla now or in the foreseeable future.
Predation--Grazing and Herbivory
Prior to conservation measures taken by the BLM, the habitat of
Boechera pusilla was grazed by cattle. Prior to 1982, cattle grazing
may have formed a threat, but the establishment of an ACEC that covers
all known locations of B. pusilla (BLM 1997, p. 34) and the presence of
an exclosure fence that encloses all of the occupied habitat (Dunder
1984, unpaginated; Marriott 1986, p. 14) have resolved this potential
threat. These protections are described in additional detail under
Factor D. Inadequacy of Existing Regulatory Mechanisms below. Insects,
such as caterpillars, do not appear to favor B. pusilla over other
vegetation (Heidel 2005, p. 10), and no known observations suggest that
herbivory from wild ungulates or small mammals is a threat. Therefore,
we do not consider predation to be a threat to B. pusilla now or in the
foreseeable future.
Summary of Factor C
We do not have any information to suggest that disease or predation
are a threat to this species. We conclude that the best scientific and
commercial information available indicates that Boechera pusilla is not
in danger of extinction or likely to become so within the foreseeable
future because of disease or predation.
Factor D. Inadequacy of Existing Regulatory Mechanisms
The Act requires us to examine the adequacy of existing regulatory
mechanisms with respect to threats that may place Boechera pusilla in
danger of extinction or likely to become so in the future. Existing
regulatory mechanisms that could have an effect on potential threats to
B. pusilla include (1) Federal laws and regulations; (2) State laws and
regulations; and (3) local land use laws, processes, and ordinances.
Because the entire population of Boechera pusilla occurs on BLM lands,
we focus our discussion on Federal laws. Actions adopted by local
groups, States, or Federal entities that are discretionary, including
conservation strategies and guidance, are not regulatory mechanisms;
however, we may discuss them in relation to their effects on potential
threats to the species.
Federal Laws and Regulations
Bureau of Land Management
Several regulatory mechanisms are in place to protect Boechera
pusilla, some of which were mentioned under Factor A. The Present or
Threatened Destruction, Modification, or Curtailment of Its Habitat or
Range above. The BLM has excluded grazing from the habitat area,
developed a habitat management plan for the species, designated the
habitat area as an ACEC, incorporated the habitat area into a SRMA, and
designated B. pusilla as a sensitive species. Additionally, the
[[Page 33956]]
Secretary of the Interior removed essentially the entire area with
occupied habitat from mineral development. The Service previously
published a notice of review in 2000 removing B. pusilla as a candidate
species, largely based on protections provided by these regulatory
mechanisms and land management approaches.
The BLM designated the Pine Creek Special Management Area in 1978
(Heidel 2005, p. 16) and built an exclosure fence in 1982 to keep
cattle out of the 35.6-ha (88-ac) area where recreational activities
occur (Dunder 1984, unpaginated). Boechera pusilla occurs within this
management area (Marriott 1986, p. 14). The fenced portion of the area
is smaller than that of the known species range, but protects much of
the occupied habitat. As described under Factor A. The Present or
Threatened Destruction, Modification, or Curtailment of Its Habitat or
Range above, the BLM provided a Habitat Management Plan for B. pusilla
(BLM 1994, entire) and processed an emergency closure of vehicle access
to 202.3 ha (500 ac) in a Habitat Management Area for the species in
1994 (59 FR 17718).
The BLM 6840 Manual requires that RMPs should address sensitive
species, and that implementation ``should consider all site-specific
methods and procedures needed to bring species and their habitats to
the condition under which management under the Bureau sensitive species
policies would no longer be necessary'' (BLM 2008, p. 2A1). The Federal
Land Policy and Management Act of 1976 mandates Federal land managers
to develop and revise land use plans. The RMPs are the basis for all
actions and authorizations involving BLM-administered lands and
resources (43 CFR 1601.0-5(n)). The 1997 RMP for the area that includes
Boechera pusilla habitat provided designation of a Special Status Plant
ACEC that closed the area to: (1) Direct surface-disturbing activities,
(2) mining claims, (3) surface occupancy and surface-disturbance
activities, (4) mineral material sales, and (5) use of explosives and
blasting (BLM 1997, p. 34). B. pusilla habitat also fits within an SRMA
designated in the RMP, which: (1) Prohibited major facilities (e.g.,
power lines), (2) closed the area to mineral leasing, (3) closed the
ACEC to ORV use, and (4) required avoidance and extensive planning of
long, linear facilities (e.g., roads) (BLM 1997, pp 17-18). All
activities concerning B. pusilla in the RMP have been implemented
(Glennon 2010b, pers. comm.). The next RMP revision for the area is
currently underway, with an estimated completion date of 2013 (Dana
2010b, pers. comm.). Existing protections for the species will likely
remain in place in the revised RMP as a no-action alternative under
NEPA, but we are uncertain whether additional protections for B.
pusilla will be developed.
National Environmental Policy Act
The entire known population of Boechera pusilla occurs on Federal
land. All Federal agencies are required to adhere to the NEPA for
projects they fund, authorize, or carry out. Please refer to the NEPA
discussion under Factor D. The Inadequacy of Existing Regulatory
Mechanisms in the Five Factor Evaluation for Abronia ammophila section
for additional information.
Public Land Order No. 7312
On February 23, 1998, the Secretary of the Interior issued Public
Land Order No. 7312 to withdraw public land from certain uses for 50
years as a measure to protect Boechera pusilla. This order withdrew
412.8 ha (1,020 ac) from settlement, sale, location of minerals, or
entry under the general land laws, including mining laws; this did not
eliminate the area from being leased under the mineral leasing laws (63
FR 9012). In addition to these measures, B. pusilla was listed as a BLM
sensitive species in 2002 (BLM 2002, p. 9).
Summary of Factor D
Because the entire population of Boechera pusilla occurs on BLM
lands, this agency has responsibility for the land management decisions
that protect B. pusilla and its habitat. B. pusilla receives adequate
protection from the BLM in the form of regulatory mechanisms,
designations, and the construction of animal exclosures. These
protections greatly limit the amount of disturbance that can occur
within the plant's limited range. Although these mechanisms do not
entirely exclude the area from foot traffic, they have adequately
reduced this potential threat. Various regulatory mechanisms are in
place to address potential threats over which the BLM has control. We
expect that B. pusilla and its habitat will be generally protected from
direct human disturbance.
We have no evidence of impacts to Boechera pusilla from inadequate
regulatory mechanisms. We recognize that the existing regulatory
mechanisms have not been able to stem the decline of the species, but
we are not able to identify that regulatory mechanisms are inadequate.
We are uncertain what is causing reduced population levels and consider
the reduction to be an indicator that a threat is present; however, we
are not able to fully describe this threat at this time (see Factor E.
Other Natural Or Manmade Factors Affecting Its Continued Existence
discussion below). The current small population size creates a
vulnerability that may work in combination with the threat that we are
not able to explain. Since the primary management tool that implements
regulatory mechanisms, the RMP, goes through revisions approximately
every 15 years (Dana 2010b, pers. comm.), it will be important for the
BLM to ensure that the protective measures are sustained in future
revisions to the Green River RMP and that measures be taken to
alleviate any potential vulnerabilities created by small population
size.
We conclude that the best scientific and commercial information
available indicates that Boechera pusilla is not in danger of
extinction or likely to become so within the foreseeable future because
of inadequate regulatory mechanisms. We recognize that the existing
regulatory mechanisms do not appear to have protected the species from
decline; however, we are unable to conclude that regulatory mechanisms
are inadequate since the cause for decline is unidentified.
Factor E. Other Natural or Manmade Factors Affecting Its Continued
Existence
Natural and manmade factors with the potential to affect Boechera
pusilla include: (1) Small population size, and (2) threats not yet
fully identified.
Small Population Size
For general background information on small population size, please
refer to the first paragraph of ``Small Population Size'' under Factor
E. Other Natural or Manmade Factors Affecting Its Continued Existence
in the Five Factor Evaluation for Abronia ammophila section.
In order for a population to sustain itself, there must be enough
reproducing individuals and habitat to ensure its survival.
Conservation biology defines this as the ``minimum viable population''
requirement (Grumbine 1990, pp. 127-128). This requirement may be
between 500 and 5,000 individuals for other species of Boechera
depending on variability among species, demographic constraints, and
evolutionary history (Ladyman 2005, p. 26). Boechera pusilla occurs in
relatively small numbers, with the total population size no greater
than
[[Page 33957]]
1,000 flowering plants in the past (Heidel 2005, p. 14) and at 350
flowering plants in 2010 (Heidel 2010d, pers. comm.). Plant numbers are
at levels that may not ensure this species' continued existence over
the long term. As noted above, botanists who have studied B. pusilla
note an overall declining trend of the species (Heidel 2005, p. 14;
Heidel 2010c, pers. comm.; Windham 2010, pers. comm.). This decline has
been rapid compared to declines observed in other rare species and has
continued after habitat protections were put in place (Windham 2010,
pers. comm.). As established in an earlier section, the number of
flowering plants in the population in 2010 was approximately 350, an
increase from 2003 estimates of 150 to 250. However, if a decline
similar to the significant decrease between 1988 (800 to 1,000
flowering plants) and 2003 (150 to 250 flowering plants) occurs again,
the species may have difficulty perpetuating itself into the future.
Boechera pusilla relies on soils formed from a certain type of
granitic outcrop that is limited in extent, so the range of the species
is not likely to expand beyond this area in the future. The relatively
small area that B. pusilla occurs within also may predispose the
species to be more sensitive to stochastic events that might occur
(Menges 1990, p. 53; Boyce 1992, pp. 482-484), such as climate shift
that the species is not adapted to or factors that lead to reduced
reproductive success (Ladyman 2005, pp. 30-31). A single unforeseen
event in a relatively small area could eliminate the species.
Boechera pusilla is apomictic, so when it uses this reproductive
process, the species essentially clones itself. We are uncertain how
long the species' apomictic seeds remain viable or under what
conditions they germinate. This reproductive process may reduce some of
the risks associated with small population size for species that only
sexually reproduce. If the species reproduces only asexually, risks
related to lack of genetic variability may increase, but we are
uncertain if B. pusilla also reproduces sexually as do some other
species of Boechera. Apomixis has been shown to reduce extinction risk
if certain other variables are present, such as high levels of biomass
and no soil acidity (Freville et al. 2007, p. 2666). However,
information on what apomixis means for conservation of a species
remains limited (Freville et al. 2007, p. 2669).
Threats Not Yet Fully Identified
In addition to the small population size of Boechera pusilla, an
unknown threat or threats may be present that is causing reduced
numbers of the plant. The species was removed from the candidate list
in 2000 based on the regulatory protections that were in place. Based
on our current understanding of the species, these regulatory
protections appear appropriate and sufficient. However, the species
still has small population numbers that have declined overall since the
implementation of these protections. We do not understand the nature of
the threat or threats, but the reduced population numbers demonstrate
that some type of threat is present. We have limited data to inform our
understanding of what this threat could be. The decline could be linked
to drought cycles, but we do not have sufficient data to correlate
numbers of B. pusilla with drought. A disease could be present in the
species, but we have no information to indicate disease is reducing the
number of plants.
Summary of Factor E
Boechera pusilla has a small population size that is confined to a
small area because of habitat requirements. The species may be
vulnerable to stochastic events due to its small population size. B.
pusilla reproduces itself asexually, which may reduce some risks of a
small population size, but does not fully eliminate this threat.
Declines have occurred in the species, even after habitat protection
measures were put in place. Although the population numbers increased
from 2003 (150-250 flowering plants) to 2010 (350 flowering plants),
numbers remain low, the plant appears to have an overall trend of
decline, and this overall trend may continue in the foreseeable future.
A viable population for the species may be 500 to 5,000 plants (Ladyman
2005, p. 26), and species numbers are below that level. We are
uncertain what is causing reduced population levels and consider the
reduction to be an indicator that a threat is present for the species.
We are not able to fully describe this threat. Some of the decline may
be attributable to drought conditions, but we do not fully understand
the cause of the decline. Additionally, disease may be present but has
not been documented. The small population size creates a vulnerability
that may work in combination with the threat that we are not able to
explain. Therefore, the species appears likely to be in danger of
extinction or likely to become so within the foreseeable future because
of the combination of small population size and a threat that we cannot
fully identify but that is manifest by an overall declining population.
Five Factor Evaluation Summary for Boechera pusilla
Boechera pusilla has a threat that is not identified, but that is
indicated by the small and declining population size. The population
size may be declining from a variety of unknown causes, with drought or
disease possibly contributing to the trend. The trend may have been
reversed somewhat, but without improved population numbers, the species
may reach a population level at which other stressors become threats.
The species may already be below the minimum viable population, so
other stressors may begin to present threats to the species. We are
unable to determine how climate change may affect the species in the
future. To the extent that we understand the species, other potential
habitat-related threats have been removed through the implementation of
Federal regulatory mechanisms and associated actions. Overutilization,
predation, and the inadequacy of regulatory mechanisms are not viewed
as threats to the species.
Finding
As required by the Act, we considered the five factors in assessing
whether Boechera pusilla is threatened or endangered throughout all of
its range. We examined the best scientific and commercial information
available regarding the past, present, and future threats faced by B.
pusilla. We reviewed the petition, information available in our files,
other available published and unpublished information, and we consulted
with recognized B. pusilla experts and other Federal agencies.
This status review identified threats to Boechera pusilla
attributable to Factor E. The primary threat to the species is from a
threat that is not fully identified, but is indicated by the species'
small, declining population size. This threat to B. pusilla is not
fully understood, but may be connected with drought conditions,
disease, or other factors. Protective measures have been taken
previously to maintain the species' habitat, but the species continues
to experience declines. B. pusilla has only one population, with most
of the individuals occurring in a single subpopulation. The range of
the species is small due to limitations of a highly specialized
habitat. Although population levels increased in 2010, the species is
experiencing an overall pattern of decline that we anticipate will
continue. B. pusilla numbers already may be below the minimum viable
population requirement, so other vulnerabilities associated with the
small population may now present threats to
[[Page 33958]]
the species. Therefore, the species appears likely to be in danger of
extinction currently, or in the foreseeable future, as result of a
threat that is not fully identified, but is manifest by an ongoing
declining population trend.
On the basis of the best scientific and commercial information
available, we find that the petitioned action to list Boechera pusilla
under the Act is warranted. We will make a determination on the status
of the species as threatened or endangered when we do a proposed
listing determination. However, as explained in more detail below, an
immediate proposal of a regulation implementing this action is
precluded by higher priority listing actions, and progress is being
made to add or remove qualified species from the Lists of Endangered
and Threatened Wildlife and Plants.
We reviewed the available information to determine if the existing
and foreseeable threats render the species at risk of extinction now
such that issuing an emergency regulation temporarily listing the
species under section 4(b)(7) of the Act is warranted. We determined
that issuing an emergency regulation temporarily listing the species is
not warranted for this species at this time, because threats to the
species would not be further controlled with a change in status.
Additionally, the most recent survey information suggests that, while
the population has not rebounded to previous highs, the population
declines also have not continued. However, if at any time we determine
that issuing an emergency regulation temporarily listing Boechera
pusilla is warranted, we will initiate this action at that time.
Listing Priority Number
The Service adopted guidelines on September 21, 1983 (48 FR 43098),
to establish a rational system for utilizing available resources for
the highest priority species when adding species to the Lists of
Endangered or Threatened Wildlife and Plants or reclassifying species
listed as threatened to endangered status. These guidelines, titled
``Endangered and Threatened Species Listing and Recovery Priority
Guidelines'' address the immediacy and magnitude of threats, and the
level of taxonomic distinctiveness by assigning priority in descending
order to monotypic genera (genus with one species), full species, and
subspecies (or equivalently, distinct population segments of
vertebrates).
As a result of our analysis of the best available scientific and
commercial information, we have assigned Boechera pusilla a Listing
Priority Number (LPN) of 8, based on our finding that the species faces
threats that are of moderate magnitude and are imminent. These threats
include a threat that is not fully identified that may work in
combination with the small population. Our rationale for assigning B.
pusilla an LPN of 8 is outlined below.
Under the Service's guidelines, the magnitude of threat is the
first criterion we look at when establishing a listing priority. The
guidance indicates that species with the highest magnitude of threat
are those species facing the greatest threats to their continued
existence. These species receive the highest listing priority. We
consider the threats that Boechera pusilla faces to be moderate in
magnitude. Although the threat, as described in Factor E. Other Natural
or Manmade Factors Affecting Its Continued Existence under Five Factor
Evaluation for Boechera pusilla, is not fully understood, we know it
exists as indicated by the declining population. Because we have not
detected the source or nature of the threat, we consider the threat to
be moderate in magnitude. The population levels have decreased
significantly from the recorded high in 1988 (800 to 1,000), but they
also increased between 2003 (150 to 250) and 2010 (350), so we do not
consider the magnitude of the threat to be high. The threat is not
fully understood, but is manifest by a declining population that may
have stabilized somewhat; therefore, we consider the magnitude of the
threat to be moderate.
Under our LPN guidelines, the second criterion we consider in
assigning a listing priority is the immediacy of threats. This
criterion is intended to ensure that the species facing actual,
identifiable threats are given priority over those for which threats
are only potential or that are intrinsically vulnerable but are not
known to be presently facing such threats. We consider the threat to
Boechera pusilla as described in Factor E. Other Natural or Manmade
Factors Affecting Its Continued Existence under Five Factor Evaluation
for Boechera pusilla to be imminent because, although not fully
identified, we have evidence that the species is currently facing a
threat indicated by reduced population size. The threat appears to be
ongoing, although we are unsure of the extent and timing of its effects
on B. pusilla. The threat is occurring in the only known population in
the United States, and the population may already be below the minimum
viable population requirement, which may allow population reductions
and increases in population vulnerability to occur more quickly in the
future. We expect some additional declines will occur in the future,
and if declines occur at rates similar to those in the past, population
levels could be precariously low. Therefore, we consider the threat to
be imminent.
The third criterion in our Listing Priority Number guidance is
intended to devote resources to those species representing highly
distinctive or isolated gene pools as reflected by taxonomy. Boechera
pusilla is a valid taxon at the species level and, therefore, receives
a higher priority than subspecies, but a lower priority than species in
a monotypic genus. Therefore, we assigned B. pusilla an LPN of 8.
We will continue to monitor the threats to Boechera pusilla and the
species' status on an annual basis, and should the magnitude or the
imminence of the threats change, we will revisit our assessment of the
LPN.
While we conclude that listing Boechera pusilla is warranted, an
immediate proposal to list this species is precluded by other higher
priority listings, which we address in the Preclusion and Expeditious
Progress section below. Because we have assigned B. pusilla an LPN of
8, work on a proposed listing determination for the species is
precluded by work on higher priority listing actions with absolute
statutory, court-ordered, or court-approved deadlines and final listing
determinations for those species that were proposed for listing with
funds from Fiscal Year (FY) 2010. This work includes all the actions
listed in the tables below under Preclusion and Expeditious Progress.
Preclusion and Expeditious Progress
Preclusion is a function of the listing priority of a species in
relation to the resources that are available and the cost and relative
priority of competing demands for those resources. Thus, in any given
FY, multiple factors dictate whether it will be possible to undertake
work on a listing proposal regulation or whether promulgation of such a
proposal is precluded by higher priority listing actions.
The resources available for listing actions are determined through
the annual Congressional appropriations process. The appropriation for
the Listing Program is available to support work involving the
following listing actions: Proposed and final listing rules; 90-day and
12-month findings on petitions to add species to the Lists of
Endangered and Threatened Wildlife and Plants (Lists) or to change the
status
[[Page 33959]]
of a species from threatened to endangered; annual ``resubmitted''
petition findings on prior warranted-but-precluded petition findings as
required under section 4(b)(3)(C)(i) of the Act; critical habitat
petition findings; proposed and final rules designating critical
habitat; and litigation-related, administrative, and program-management
functions (including preparing and allocating budgets, responding to
Congressional and public inquiries, and conducting public outreach
regarding listing and critical habitat).
The work involved in preparing various listing documents can be
extensive and may include, but is not limited to: Gathering and
assessing the best scientific and commercial data available and
conducting analyses used as the basis for our decisions; writing and
publishing documents; and obtaining, reviewing, and evaluating public
comments and peer review comments on proposed rules and incorporating
relevant information into final rules. The number of listing actions
that we can undertake in a given year also is influenced by the
complexity of those listing actions; that is, more complex actions
generally are more costly. The median cost for preparing and publishing
a 90-day finding is $39,276; for a 12-month finding, $100,690; for a
proposed rule with critical habitat, $345,000; and for a final listing
rule with critical habitat, the median cost is $305,000.
We cannot spend more than is appropriated for the Listing Program
without violating the Anti-Deficiency Act (see 31 U.S.C.
1341(a)(1)(A)). In addition, in FY 1998 and for each FY since then,
Congress has placed a statutory cap on funds which may be expended for
the Listing Program, equal to the amount expressly appropriated for
that purpose in that FY. This cap was designed to prevent funds
appropriated for other functions under the Act (for example, recovery
funds for removing species from the Lists), or for other Service
programs, from being used for Listing Program actions (see House Report
105-163, 105th Congress, 1st Session, July 1, 1997).
Since FY 2002, the Service's budget has included a critical habitat
subcap to ensure that some funds are available for other work in the
Listing Program (``The critical habitat designation subcap will ensure
that some funding is available to address other listing activities''
(House Report No. 107-103, 107th Congress, 1st Session, June 19,
2001)). In FY 2002 and each year until FY 2006, the Service had to use
virtually the entire critical habitat subcap to address court-mandated
designations of critical habitat, and consequently none of the critical
habitat subcap funds were available for other listing activities. In
some FYs since 2006, we have been able to use some of the critical
habitat subcap funds to fund proposed listing determinations for high-
priority candidate species. In other FYs, while we were unable to use
any of the critical habitat subcap funds to fund proposed listing
determinations, we did use some of this money to fund the critical
habitat portion of some proposed listing determinations so that the
proposed listing determination and proposed critical habitat
designation could be combined into one rule, thereby being more
efficient in our work. In FY 2011 we anticipate that we will be able to
use some of the critical habitat subcap funds to fund proposed listing
determinations.
We make our determinations of preclusion on a nationwide basis to
ensure that the species most in need of listing will be addressed first
and also because we allocate our listing budget on a nationwide basis.
Through the listing cap, the critical habitat subcap, and the amount of
funds needed to address court-mandated critical habitat designations,
Congress and the courts have in effect determined the amount of money
available for other listing activities nationwide. Therefore, the funds
in the listing cap, other than those needed to address court-mandated
critical habitat for already listed species, set the limits on our
determinations of preclusion and expeditious progress.
Congress identified the availability of resources as the only basis
for deferring the initiation of a rulemaking that is warranted. The
Conference Report accompanying Pub. L. 97-304, which established the
current statutory deadlines and the warranted-but-precluded finding,
states that the amendments were ``not intended to allow the Secretary
to delay commencing the rulemaking process for any reason other than
that the existence of pending or imminent proposals to list species
subject to a greater degree of threat would make allocation of
resources to such a petition [that is, for a lower-ranking species]
unwise.'' Although that statement appeared to refer specifically to the
``to the maximum extent practicable'' limitation on the 90-day deadline
for making a ``substantial information'' finding, that finding is made
at the point when the Service is deciding whether or not to commence a
status review that will determine the degree of threats facing the
species, and therefore the analysis underlying the statement is more
relevant to the use of the warranted-but-precluded finding, which is
made when the Service has already determined the degree of threats
facing the species and is deciding whether or not to commence a
rulemaking.
In FY 2010, $10,471,000 is the amount of money that Congress
appropriated for the Listing Program (that is, the portion of the
Listing Program funding not related to critical habitat designations
for species that are already listed). Therefore, a proposed listing is
precluded if pending proposals with higher priority will require
expenditure of at least $10,471,000, and expeditious progress is the
amount of work that can be achieved with $10,471,000. Since court
orders requiring critical habitat work will not require use of all of
the funds within the critical habitat subcap, we used $1,114,417 of our
critical habitat subcap funds in order to work on as many of our
required petition findings and listing determinations as possible. This
brings the total amount of funds we had for listing actions in FY 2010
to $11,585,417.
The $11,585,417 was used to fund work in the following categories:
Compliance with court orders and court-approved settlement agreements
requiring that petition findings or listing determinations be completed
by a specific date; section 4 (of the Act) listing actions with
absolute statutory deadlines; essential litigation-related,
administrative, and listing program-management functions; and high-
priority listing actions for some of our candidate species. For FY
2011, on September 29, 2010, Congress passed a continuing resolution
which provides funding at the FY 2010 enacted level. Until Congress
appropriates funds for FY 2011, we will fund listing work based on the
FY 2010 amount. In 2009, the responsibility for listing foreign species
under the Act was transferred from the Division of Scientific
Authority, International Affairs Program, to the Endangered Species
Program. Therefore, starting in FY 2010, we use a portion of our
funding to work on the actions described above as they apply to listing
actions for foreign species. This has the potential to further reduce
funding available for domestic listing actions. Although there are
currently no foreign species issues included in our high-priority
listing actions at this time, many actions have statutory or court-
approved settlement deadlines, thus increasing their priority. The
budget allocations for each specific listing action are identified in
the Service's FY 2011 Allocation Table (part of our administrative
record).
[[Page 33960]]
Based on our September 21, 1983, guidance for assigning an LPN for
each candidate species (48 FR 43098), we have a significant number of
species with a LPN of 2. Using this guidance, we assign each candidate
an LPN of 1 to 12, depending on the magnitude of threats (high or
moderate to low), immediacy of threats (imminent or nonimminent), and
taxonomic status of the species (in order of priority: monotypic genus
(a species that is the sole member of a genus); species; or part of a
species (subspecies, distinct population segment, or significant
portion of the range)). The lower the listing priority number, the
higher the listing priority (that is, a species with an LPN of 1 would
have the highest listing priority).
Because of the large number of high-priority species, we have
further ranked the candidate species with an LPN of 2 by using the
following extinction-risk type criteria: International Union for the
Conservation of Nature and Natural Resources (IUCN) Red list status/
rank, Heritage rank (provided by NatureServe), Heritage threat rank
(provided by NatureServe), and species currently with fewer than 50
individuals, or 4 or fewer populations. Those species with the highest
IUCN rank (critically endangered), the highest Heritage rank (G1), the
highest Heritage threat rank (substantial, imminent threats), and
currently with fewer than 50 individuals, or fewer than 4 populations,
originally comprised a group of approximately 40 candidate species
(``Top 40''). These 40 candidate species have had the highest priority
to receive funding to work on a proposed listing determination. As we
work on proposed and final listing rules for those 40 candidates, we
apply the ranking criteria to the next group of candidates with an LPN
of 2 and 3 to determine the next set of highest priority candidate
species. Finally, proposed rules for reclassification of threatened
species to endangered are lower priority, since as listed species, they
are already afforded the protection of the Act and implementing
regulations. However, for efficiency reasons, we may choose to work on
a proposed rule to reclassify a species to endangered if we can combine
this with work that is subject to a court-determined deadline.
We assigned Boechera pusilla an LPN of 8. This is based on our
finding that the species faces immediate and moderate magnitude threats
from a threat we do not fully understand but is manifest by reduced
population levels that may be below the minimum viable population
requirement. Under our 1983 Guidelines, a ``species'' facing imminent
moderate-magnitude threats is assigned an LPN of 7, 8, or 9 depending
on its taxonomic status. Because B. pusilla is a species, we assigned
it an LPN of 8. Therefore, work on a proposed listing determination for
B. pusilla is precluded by work on higher priority candidate species
(i.e., species with LPN of 7); listing actions with absolute statutory,
court ordered, or court-approved deadlines; and final listing
determinations for those species that were proposed for listing with
funds from previous FYs. This work includes all the actions listed in
the tables below under expeditious progress.
With our workload so much bigger than the amount of funds we have
to accomplish it, it is important that we be as efficient as possible
in our listing process. Therefore, as we work on proposed rules for the
highest priority species in the next several years, we are preparing
multi-species proposals when appropriate, and these may include species
with lower priority if they overlap geographically or have the same
threats as a species with an LPN of 2. In addition, we take into
consideration the availability of staff resources when we determine
which high-priority species will receive funding to minimize the amount
of time and resources required to complete each listing action.
As explained above, a determination that listing is warranted but
precluded also must demonstrate that expeditious progress is being made
to add and remove qualified species to and from the Lists of Endangered
and Threatened Wildlife and Plants. As with our ``precluded'' finding,
the evaluation of whether progress in adding qualified species to the
Lists has been expeditious is a function of the resources available for
listing and the competing demands for those funds. (Although we do not
discuss it in detail here, we also are making expeditious progress in
removing species from the list under the Recovery program in light of
the resource available for delisting, which is funded by a separate
line item in the budget of the Endangered Species Program. During FY
2010, we have completed two proposed delisting rules and two final
delisting rules.) Given the limited resources available for listing, we
find that we made expeditious progress in FY 2010 in the Listing
Program and are making expeditious progress in FY 2011. This progress
included preparing and publishing the following determinations:
FY 2010 and FY 2011 Completed Listing Actions
----------------------------------------------------------------------------------------------------------------
Publication date Title Actions FR pages
----------------------------------------------------------------------------------------------------------------
10/08/2009................ Listing Lepidium Final Listing 74 FR 52013-52064.
papilliferum (Slickspot Threatened.
Peppergrass) as a
Threatened Species
Throughout Its Range.
10/27/2009................ 90-day Finding on a Notice of 90-day 74 FR 55177-55180.
Petition To List the Petition Finding,
American Dipper in the Not substantial.
Black Hills of South
Dakota as Threatened or
Endangered.
10/28/2009................ Status Review of Arctic Notice of Intent to 74 FR 55524-55525.
Grayling (Thymallus Conduct Status
arcticus) in the Upper Review for Listing
Missouri River System. Decision.
11/03/2009................ Listing the British Proposed Listing 74 FR 56757-56770.
Columbia Distinct Threatened.
Population Segment of
the Queen Charlotte
Goshawk Under the
Endangered Species Act:
Proposed rule.
11/03/2009................ Listing the Salmon- Proposed Listing 74 FR 56770-56791.
Crested Cockatoo as Threatened.
Threatened Throughout
Its Range with Special
Rule.
11/23/2009................ Status Review of Gunnison Notice of Intent to 74 FR 61100-61102.
sage-grouse Conduct Status
(Centrocercus minimus). Review for Listing
Decision.
12/03/2009................ 12-Month Finding on a Notice of 12-month 74 FR 63343-63366.
Petition to List the petition finding,
Black-tailed Prairie Dog Not warranted.
as Threatened or
Endangered.
12/03/2009................ 90-Day Finding on a Notice of 90-day 74 FR 63337-63343.
Petition to List Petition Finding,
Sprague's Pipit as Substantial.
Threatened or Endangered.
[[Page 33961]]
12/15/2009................ 90-Day Finding on Notice of 90-day 74 FR 66260-66271.
Petitions To List Nine Petition Finding,
Species of Mussels From Substantial.
Texas as Threatened or
Endangered With Critical
Habitat.
12/16/2009................ Partial 90-Day Finding on Notice of 90-day 74 FR 66865-66905.
a Petition to List 475 Petition Finding,
Species in the Not substantial &
Southwestern United Substantial.
States as Threatened or
Endangered With Critical
Habitat.
12/17/2009................ 12-month Finding on a Notice of 12-month 74 FR 66937-66950.
Petition To Change the petition finding,
Final Listing of the Warranted but
Distinct Population precluded.
Segment of the Canada
Lynx To Include New
Mexico.
01/05/2010................ Listing Foreign Bird Proposed Listing 75 FR 605-649.
Species in Peru & Endangered.
Bolivia as Endangered
Throughout Their Range.
01/05/2010................ Listing Six Foreign Birds Proposed Listing 75 FR 286-310.
as Endangered Throughout Endangered.
Their Range.
01/05/2010................ Withdrawal of Proposed Proposed rule, 75 FR 310-316.
Rule to List Cook's withdrawal.
Petrel.
01/05/2010................ Final Rule to List the Final Listing 75 FR 235-250.
Galapagos Petrel & Threatened.
Heinroth's Shearwater as
Threatened Throughout
Their Ranges.
01/20/2010................ Initiation of Status Notice of Intent to 75 FR 3190-3191.
Review for Agave Conduct Status
eggersiana & Solanum Review for Listing
conocarpum. Decision.
02/09/2010................ 12-month Finding on a Notice of 12-month 75 FR 6437-6471.
Petition to List the petition finding,
American Pika as Not warranted.
Threatened or Endangered.
02/25/2010................ 12-Month Finding on a Notice of 12-month 75 FR 8601-8621.
Petition To List the petition finding,
Sonoran Desert Not warranted.
Population of the Bald
Eagle as a Threatened or
Endangered Distinct
Population Segment.
02/25/2010................ Withdrawal of Proposed Withdrawal of 75 FR 8621-8644.
Rule To List the Proposed Rule to
Southwestern Washington/ List.
Columbia River Distinct
Population Segment of
Coastal Cutthroat Trout
(Oncorhynchus clarki
clarki) as Threatened.
03/18/2010................ 90-Day Finding on a Notice of 90-day 75 FR 13068-13071.
Petition to List the Petition Finding,
Berry Cave salamander as Substantial.
Endangered.
03/23/2010................ 90-Day Finding on a Notice of 90-day 75 FR 13717-13720.
Petition to List the Petition Finding,
Southern Hickorynut Not substantial.
Mussel (Obovaria
jacksoniana) as
Endangered or Threatened.
03/23/2010................ 90-Day Finding on a Notice of 90-day 75 FR 13720-13726.
Petition to List the Petition Finding,
Striped Newt as Substantial.
Threatened.
03/23/2010................ 12-Month Findings for Notice of 12-month 75 FR 13910-14014.
Petitions to List the petition finding,
Greater Sage-Grouse Warranted but
(Centrocercus precluded.
urophasianus) as
Threatened or Endangered.
03/31/2010................ 12-Month Finding on a Notice of 12-month 75 FR 16050-16065.
Petition to List the petition finding,
Tucson Shovel-Nosed Warranted but
Snake (Chionactis precluded.
occipitalis klauberi) as
Threatened or Endangered
with Critical Habitat.
04/05/2010................ 90-Day Finding on a Notice of 90-day 75 FR 17062-17070.
Petition To List Petition Finding,
Thorne's Hairstreak Substantial.
Butterfly as threatened
or Endangered.
04/06/2010................ 12-month Finding on a Notice of 12-month 75 FR 17352-17363.
Petition To List the petition finding,
Mountain Whitefish in Not warranted.
the Big Lost River,
Idaho, as Endangered or
Threatened.
04/06/2010................ 90-Day Finding on a Notice of 90-day 75 FR 17363-17367.
Petition to List a Petition Finding,
Stonefly (Isoperla Not substantial.
jewetti) & a Mayfly
(Fallceon eatoni) as
Threatened or Endangered
with Critical Habitat.
04/7/2010................. 12-Month Finding on a Notice of 12-month 75 FR 17667-17680.
Petition to Reclassify petition finding,
the Delta Smelt From Warranted but
Threatened to Endangered precluded.
Throughout Its Range.
04/13/2010................ Determination of Final Listing 75 FR 18959-19165.
Endangered Status for 48 Endangered.
Species on Kauai &
Designation of Critical
Habitat.
04/15/2010................ Initiation of Status Notice of Initiation 75 FR 19591-19592.
Review of the North of Status Review
American Wolverine in for Listing
the Contiguous United Decision.
States.
04/15/2010................ 12-Month Finding on a Notice of 12-month 75 FR 19592-19607.
Petition to List the petition finding,
Wyoming Pocket Gopher as Not warranted.
Endangered or Threatened
with Critical Habitat.
04/16/2010................ 90-Day Finding on a Notice of 90-day 75 FR 19925-19935.
Petition to List a Petition Finding,
Distinct Population Substantial.
Segment of the Fisher in
Its United States
Northern Rocky Mountain
Range as Endangered or
Threatened with Critical
Habitat.
04/20/2010................ Initiation of Status Notice of Initiation 75 FR 20547-20548.
Review for Sacramento of Status Review
splittail (Pogonichthys for Listing
macrolepidotus). Decision.
04/26/2010................ 90-Day Finding on a Notice of 90-day 75 FR 21568-21571.
Petition to List the Petition Finding,
Harlequin Butterfly as Substantial.
Endangered.
04/27/2010................ 12-Month Finding on a Notice of 12-month 75 FR 22012-22025.
Petition to List Susan's petition finding,
Purse-making Caddisfly Not warranted.
(Ochrotrichia susanae)
as Threatened or
Endangered.
[[Page 33962]]
04/27/2010................ 90-day Finding on a Notice of 90-day 75 FR 22063-22070.
Petition to List the Petition Finding,
Mohave Ground Squirrel Substantial.
as Endangered with
Critical Habitat.
05/04/2010................ 90-Day Finding on a Notice of 90-day 75 FR 23654-23663.
Petition to List Hermes Petition Finding,
Copper Butterfly as Substantial.
Threatened or Endangered.
06/01/2010................ 90-Day Finding on a Notice of 90-day 75 FR 30313-30318.
Petition To List Petition Finding,
Castanea pumila var. Substantial.
ozarkensis.
06/01/2010................ 12-month Finding on a Notice of 12-month 75 FR 30338-30363.
Petition to List the petition finding,
White-tailed Prairie Dog Not warranted.
as Endangered or
Threatened.
06/09/2010................ 90-Day Finding on a Notice of 90-day 75 FR 32728-32734.
Petition To List van Petition Finding,
Rossem's Gull-billed Substantial.
Tern as Endangered or
Threatened.
06/16/2010................ 90-Day Finding on Five Notice of 90-day 75 FR 34077-34088.
Petitions to List Seven Petition Finding,
Species of Hawaiian Substantial.
Yellow-faced Bees as
Endangered.
06/22/2010................ 12-Month Finding on a Notice of 12-month 75 FR 35398-35424.
Petition to List the petition finding,
Least Chub as Threatened Warranted but
or Endangered. precluded.
06/23/2010................ 90-Day Finding on a Notice of 90-day 75 FR 35746-35751.
Petition to List the Petition Finding,
Honduran Emerald Substantial.
Hummingbird as
Endangered.
06/23/2010................ Listing Ipomopsis Proposed Listing 75 FR 35721-35746.
polyantha (Pagosa Endangered Proposed
Skyrocket) as Endangered Listing Threatened.
Throughout Its Range, &
Listing Penstemon
debilis (Parachute
Beardtongue) & Phacelia
submutica (DeBeque
Phacelia) as Threatened
Throughout Their Range.
06/24/2010................ Listing the Flying Earwig Final Listing 75 FR 35990-36012.
Hawaiian Damselfly & Endangered.
Pacific Hawaiian
Damselfly As Endangered
Throughout Their Ranges.
06/24/2010................ Listing the Cumberland Proposed Listing 75 FR 36035-36057.
Darter, Rush Darter, Endangered.
Yellowcheek Darter,
Chucky Madtom, & Laurel
Dace as Endangered
Throughout Their Ranges.
06/29/2010................ Listing the Mountain Reinstatement of 75 FR 37353-37358.
Plover as Threatened. Proposed Listing
Threatened.
07/20/2010................ 90-Day Finding on a Notice of 90-day 75 FR 42033-42040.
Petition to List Pinus Petition Finding,
albicaulis (Whitebark Substantial.
Pine) as Endangered or
Threatened with Critical
Habitat.
07/20/2010................ 12-Month Finding on a Notice of 12-month 75 FR 42040-42054.
Petition to List the petition finding,
Amargosa Toad as Not warranted.
Threatened or Endangered.
07/20/2010................ 90-Day Finding on a Notice of 90-day 75 FR 42059-42066.
Petition to List the Petition Finding,
Giant Palouse Earthworm Substantial.
(Driloleirus americanus)
as Threatened or
Endangered.
07/27/2010................ Determination on Listing Final Listing 75 FR 43844-43853.
the Black-Breasted Endangered.
Puffleg as Endangered
Throughout its Range;
Final Rule.
07/27/2010................ Final Rule to List the Final Listing 75 FR 43853-43864.
Medium Tree-Finch Endangered.
(Camarhynchus pauper) as
Endangered Throughout
Its Range.
08/03/2010................ Determination of Final Listing 75 FR 45497-45527.
Threatened Status for Threatened.
Five Penguin Species.
08/04/2010................ 90-Day Finding on a Notice of 90-day 75 FR 46894-46898.
Petition To List the Petition Finding,
Mexican Gray Wolf as an Substantial.
Endangered Subspecies
With Critical Habitat.
08/10/2010................ 90-Day Finding on a Notice of 90-day 75 FR 48294-48298.
Petition to List Petition Finding,
Arctostaphylos Substantial.
franciscana as
Endangered with Critical
Habitat.
08/17/2010................ Listing Three Foreign Final Listing 75 FR 50813-50842.
Bird Species from Latin Endangered.
America & the Caribbean
as Endangered Throughout
Their Range.
08/17/2010................ 90-Day Finding on a Notice of 90-day 75 FR 50739-50742.
Petition to List Brian Petition Finding,
Head Mountainsnail as Not substantial.
Endangered or Threatened
with Critical Habitat.
08/24/2010................ 90-Day Finding on a Notice of 90-day 75 FR 51969-51974.
Petition to List the Petition Finding,
Oklahoma Grass Pink Substantial.
Orchid as Endangered or
Threatened.
09/01/2010................ 12-Month Finding on a Notice of 12-month 75 FR 53615-53629.
Petition to List the petition finding,
White-Sided Jackrabbit Not warranted.
as Threatened or
Endangered.
09/08/2010................ Proposed Rule To List the Proposed Listing 75 FR 54561-54579.
Ozark Hellbender Endangered.
Salamander as Endangered.
09/08/2010................ Revised 12-Month Finding Notice of 12-month 75 FR 54707-54753.
to List the Upper petition finding,
Missouri River Distinct Warranted but
Population Segment of precluded.
Arctic Grayling as
Endangered or Threatened.
09/09/2010................ 12-Month Finding on a Notice of 12-month 75 FR 54822-54845.
Petition to List the petition finding,
Jemez Mountains Warranted but
Salamander (Plethodon precluded.
neomexicanus) as
Endangered or Threatened
with Critical Habitat.
09/15/2010................ 12-Month Finding on a Notice of 12-month 75 FR 56028-56050.
Petition to List petition finding,
Sprague's Pipit as Warranted but
Endangered or Threatened precluded.
Throughout Its Range.
09/22/2010................ 12-Month Finding on a Notice of 12-month 75 FR 57720-57734.
Petition to List Agave petition finding,
eggersiana (no common Warranted but
name) as Endangered. precluded.
[[Page 33963]]
09/28/2010................ Determination of Final Listing 75 FR 59645-59656.
Endangered Status for Endangered.
the African Penguin.
09/28/2010................ Determination for the Notice of 12-month 75 FR 59803-59863.
Gunnison Sage-grouse as petition finding,
a Threatened or Warranted but
Endangered Species. precluded.
09/30/2010................ 12-Month Finding on a Notice of 12-month 75 FR 60515-60561.
Petition to List the petition finding,
Pygmy Rabbit as Not warranted.
Endangered or Threatened.
10/06/2010................ Endangered Status for the Proposed Listing 75 FR 61664-61690.
Altamaha Spinymussel & Endangered.
Designation of Critical
Habitat.
10/7/2010................. 12-month Finding on a Notice of 12-month 75 FR 62070-62095.
Petition to list the petition finding,
Sacramento Splittail as Not warranted.
Endangered or Threatened.
10/28/2010................ Endangered Status & Proposed Listing 75 FR 66481-66552.
Designation of Critical Endangered
Habitat for Spikedace & (uplisting).
Loach Minnow.
11/2/2010................. 90-Day Finding on a Notice of 90-day 75 FR 67341-67343.
Petition to List the Bay Petition Finding,
Springs Salamander as Not substantial.
Endangered.
11/2/2010................. Determination of Final Listing 75 FR 67511-67550.
Endangered Status for Endangered.
the Georgia Pigtoe
Mussel, Interrupted
Rocksnail, & Rough
Hornsnail & Designation
of Critical Habitat.
11/2/2010................. Listing the Rayed Bean & Proposed Listing 75 FR 67551-67583.
Snuffbox as Endangered. Endangered.
11/4/2010................. 12-Month Finding on a Notice of 12-month 75 FR 67925-67944.
Petition to List Cirsium petition finding,
wrightii (Wright's Marsh Warranted but
Thistle) as Endangered precluded.
or Threatened.
----------------------------------------------------------------------------------------------------------------
Our expeditious progress also includes work on listing actions
that we funded in FY 2010 and FY 2011 but have not yet been completed
to date. These actions are listed below. Actions in the top section of
the table are being conducted under a deadline set by a court. Actions
in the middle section of the table are being conducted to meet
statutory timelines, that is, timelines required under the Act. Actions
in the bottom section of the table are high-priority listing actions.
These actions include work primarily on species with an LPN of 2, and,
as discussed above, selection of these species is partially based on
available staff resources, and when appropriate, include species with a
lower priority if they overlap geographically or have the same threats
as the species with the high priority. Including these species together
in the same proposed rule results in considerable savings in time and
funding, as compared to preparing separate proposed rules for each of
them in the future.
Actions Funded in FY 2010 and FY 2011 but Not Yet Completed
----------------------------------------------------------------------------------------------------------------
Species Action
----------------------------------------------------------------------------------------------------------------
Actions Subject to Court Order/Settlement Agreement
----------------------------------------------------------------------------------------------------------------
6 Birds from Eurasia................... Final listing determination.
Flat-tailed horned lizard.............. Final listing determination.
Mountain plover \4\.................... Final listing determination.
6 Birds from Peru...................... Proposed listing determination.
Pacific walrus......................... 12-month petition finding.
Wolverine.............................. 12-month petition finding.
Solanum conocarpum..................... 12-month petition finding.
Desert tortoise--Sonoran population.... 12-month petition finding.
Thorne's Hairstreak butterfly \3\...... 12-month petition finding.
Hermes copper butterfly \3\............ 12-month petition finding.
Utah prairie dog (uplisting)........... 90-day petition finding.
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Actions With Statutory Deadlines
----------------------------------------------------------------------------------------------------------------
Casey's june beetle.................... Final listing determination.
7 Bird species from Brazil............. Final listing determination.
Southern rockhopper penguin--Campbell Final listing determination.
Plateau population.
5 Bird species from Colombia and Final listing determination.
Ecuador.
Queen Charlotte goshawk................ Final listing determination.
5 species southeast fish (Cumberland Final listing determination.
darter, rush darter, yellowcheek
darter, chucky madtom, and laurel
dace) \4\.
Ozark hellbender \4\................... Final listing determination.
Altamaha spinymussel \3\............... Final listing determination.
3 Colorado plants (Ipomopsis polyantha Final listing determination.
(Pagosa Skyrocket), Penstemon debilis
(Parachute Beardtongue), and Phacelia
submutica (DeBeque Phacelia)) \4\.
Salmon crested cockatoo................ Final listing determination.
Loggerhead sea turtle (assist National Final listing determination.
Marine Fisheries Service) \5\.
2 mussels (rayed bean (LPN = 2), Final listing determination.
snuffbox No LPN) \5\.
Mt Charleston blue \5\................. Proposed listing determination.
CA golden trout \4\.................... 12-month petition finding.
Black-footed albatross................. 12-month petition finding.
[[Page 33964]]
Mount Charleston blue butterfly........ 12-month petition finding.
Mojave fringe-toed lizard \1\.......... 12-month petition finding.
Kokanee--Lake Sammamish population \1\. 12-month petition finding.
Cactus ferruginous pygmy-owl \1\....... 12-month petition finding.
Northern leopard frog.................. 12-month petition finding.
Tehachapi slender salamander........... 12-month petition finding.
Coqui Llanero.......................... 12-month petition finding/Proposed listing.
Dusky tree vole........................ 12-month petition finding.
3 MT invertebrates (mist 12-month petition finding.
forestfly(Lednia tumana), Oreohelix
sp.3, Oreohelix sp. 31) from 206
species petition.
5 UT plants (Astragalus hamiltonii, 12-month petition finding.
Eriogonum soredium, Lepidium ostleri,
Penstemon flowersii, Trifolium
friscanum) from 206 species petition.
2 CO plants (Astragalus microcymbus, 12-month petition finding.
Astragalus schmolliae) from 206
species petition.
5 WY plants (Abronia ammophila, 12-month petition finding.
Agrostis rossiae, Astragalus
proimanthus, Boechere (Arabis)
pusilla, Penstemon gibbensii) from 206
species petition.
Leatherside chub (from 206 species 12-month petition finding.
petition).
Frigid ambersnail (from 206 species 12-month petition finding.
petition) \3\.
Platte River caddisfly (from 206 12-month petition finding.
species petition) \5\.
Gopher tortoise--eastern population.... 12-month petition finding.
Grand Canyon scorpion (from 475 species 12-month petition finding.
petition).
Anacroneuria wipukupa (a stonefly from 12-month petition finding.
475 species petition) \4\.
Rattlesnake-master borer moth (from 475 12-month petition finding.
species petition) \3\.
3 Texas moths (Ursia furtiva, 12-month petition finding.
Sphingicampa blanchardi, Agapema
galbina) (from 475 species petition).
2 Texas shiners (Cyprinella sp., 12-month petition finding.
Cyprinella lepida) (from 475 species
petition).
3 South Arizona plants (Erigeron 12-month petition finding.
piscaticus, Astragalus hypoxylus,
Amoreuxia gonzalezii) (from 475
species petition).
5 Central Texas mussel species (3 from 12-month petition finding.
475 species petition).
14 parrots (foreign species)........... 12-month petition finding.
Berry Cave salamander \1\.............. 12-month petition finding.
Striped Newt \1\....................... 12-month petition finding.
Fisher--Northern Rocky Mountain Range 12-month petition finding.
\1\.
Mohave Ground Squirrel \1\............. 12-month petition finding.
Puerto Rico Harlequin Butterfly \3\.... 12-month petition finding.
Western gull-billed tern............... 12-month petition finding.
Ozark chinquapin (Castanea pumila var. 12-month petition finding.
ozarkensis) \4\.
HI yellow-faced bees................... 12-month petition finding.
Giant Palouse earthworm................ 12-month petition finding.
Whitebark pine......................... 12-month petition finding.
OK grass pink (Calopogon oklahomensis) 12-month petition finding.
\1\.
Ashy storm-petrel \5\.................. 12-month petition finding.
Southeastern pop snowy plover & 90-day petition finding.
wintering pop. of piping plover \1\.
Eagle Lake trout \1\................... 90-day petition finding.
Smooth-billed ani \1\.................. 90-day petition finding.
32 Pacific Northwest mollusks species 90-day petition finding.
(snails and slugs) \1\.
42 snail species (Nevada & Utah)....... 90-day petition finding.
Red knot roselaari subspecies.......... 90-day petition finding.
Peary caribou.......................... 90-day petition finding.
Plains bison........................... 90-day petition finding.
Spring Mountains checkerspot butterfly. 90-day petition finding.
Spring pygmy sunfish................... 90-day petition finding.
Bay skipper............................ 90-day petition finding.
Unsilvered fritillary.................. 90-day petition finding.
Texas kangaroo rat..................... 90-day petition finding.
Spot-tailed earless lizard............. 90-day petition finding.
Eastern small-footed bat............... 90-day petition finding.
Northern long-eared bat................ 90-day petition finding.
Prairie chub........................... 90-day petition finding.
10 species of Great Basin butterfly.... 90-day petition finding.
6 sand dune (scarab) beetles........... 90-day petition finding.
Golden-winged warbler \4\.............. 90-day petition finding.
Sand-verbena moth...................... 90-day petition finding.
404 Southeast species.................. 90-day petition finding.
Franklin's bumble bee \4\.............. 90-day petition finding.
2 Idaho snowflies (straight snowfly & 90-day petition finding.
Idaho snowfly) \4\.
American eel \4\....................... 90-day petition finding.
Gila monster (Utah population) \4\..... 90-day petition finding.
Arapahoe snowfly \4\................... 90-day petition finding.
Leona's little blue \4\................ 90-day petition finding.
Aztec gilia \5\........................ 90-day petition finding.
White-tailed ptarmigan \5\............. 90-day petition finding.
San Bernardino flying squirrel \5\..... 90-day petition finding.
[[Page 33965]]
Bicknell's thrush \5\.................. 90-day petition finding.
Sonoran talussnail \5\................. 90-day petition finding.
2 AZ Sky Island plants (Graptopetalum 90-day petition finding.
bartrami & Pectis imberbis) \5\.
I'iwi \5\.............................. 90-day petition finding.
------------------------------------------------------------------------
High-Priority Listing Actions
----------------------------------------------------------------------------------------------------------------
19 Oahu candidate species \2\ (16 Proposed listing.
plants, 3 damselflies) (15 with LPN =
2, 3 with LPN = 3, 1 with LPN =9).
19 Maui-Nui candidate species \2\ (16 Proposed listing.
plants, 3 tree snails) (14 with LPN =
2, 2 with LPN = 3, 3 with LPN = 8).
Dune sagebrush lizard (formerly Sand Proposed listing.
dune lizard) \4\ (LPN = 2).
2 Arizona springsnails \2\ (Pyrgulopsis Proposed listing.
bernadina (LPN = 2), Pyrgulopsis
trivialis (LPN = 2)).
New Mexico springsnail \2\ (Pyrgulopsis Proposed listing.
chupaderae (LPN = 2).
2 mussels \2\ (sheepnose (LPN = 2), Proposed listing.
spectaclecase (LPN = 4),).
8 Gulf Coast mussels (southern Proposed listing.
kidneyshell (LPN = 2), round
ebonyshell (LPN = 2), Alabama
pearlshell (LPN = 2), southern
sandshell (LPN = 5), fuzzy pigtoe (LPN
= 5), Choctaw bean (LPN = 5), narrow
pigtoe (LPN = 5), and tapered pigtoe
(LPN = 11)) \4\.
Umtanum buckwheat (LPN = 2) \4\........ Proposed listing.
Grotto sculpin (LPN = 2) \4\........... Proposed listing.
2 Arkansas mussels (Neosho mucket (LPN Proposed listing.
=2) & Rabbitsfoot (LPN = 9)) \4\.
Diamond darter (LPN = 2) \4\........... Proposed listing.
Gunnison sage-grouse (LPN =2) \4\...... Proposed listing.
Miami blue (LPN = 3) \3\............... Proposed listing.
4 Texas salamanders (Austin blind Proposed listing.
salamander (LPN = 2), Salado
salamander (LPN = 2), Georgetown
salamander (LPN = 8), Jollyville
Plateau (LPN = 8)) \3\.
5 SW aquatics (Gonzales Spring Snail Proposed listing.
(LPN = 2), Diamond Y springsnail (LPN
=2), Phantom springsnail (LPN = 2),
Phantom Cave snail (LPN = 2),
Diminutive amphipod (LPN = 2)) \3\.
2 Texas plants (Texas golden gladecress Proposed listing.
(Leavenworthia texana) (LPN = 2),
Neches River rose-mallow (Hibiscus
dasycalyx) (LPN = 2)) \3\.
FL bonneted bat (LPN =2) \3\........... Proposed listing.
Kittlitz's murrelet (LPN = 2) \5\...... Proposed listing.
Umtanum buckwheat (LPN = 2) \3\........ Proposed listing.
21 Big Island (HI) species \5\ Proposed listing.
(includes 8 candidate species--5
plants & 3 animals; 4 with LPN = 2, 1
with LPN = 3, 1 with LPN = 4, 2 with
LPN = 8).
Oregon spotted frog (LPN = 2) \5\...... Proposed listing.
2 TN River mussels (fluted kidneyshell Proposed listing.
(LPN = 2), slabside pearlymussel (LPN
= 2) \5\.
Jemez Mountain salamander (LPN = 2) \5\ Proposed listing.
----------------------------------------------------------------------------------------------------------------
\1\ Funds for listing actions for these species were provided in previous FYs.
\2\ Although funds for these high-priority listing actions were provided in FY 2008 or 2009, due to the
complexity of these actions and competing priorities, these actions are still being developed.
\3\ Partially funded with FY 2010 funds and FY 2011 funds.
\4\ Funded with FY 2010 funds.
\5\ Funded with FY 2011 funds.
We have endeavored to make our listing actions as efficient and
timely as possible, given the requirements of the relevant law and
regulations, and constraints relating to workload and personnel. We are
continually considering ways to streamline processes or achieve
economies of scale, such as by batching related actions together. Given
our limited budget for implementing section 4 of the Act, these actions
described above collectively constitute expeditious progress.
Boechera pusilla will be added to the list of candidate species
upon publication of this 12-month finding. We will continue to evaluate
this species as new information becomes available. Continuing review
will determine if a change in status is warranted, including the need
to make prompt use of emergency listing procedures.
We intend that any proposed listing determination for Boechera
pusilla will be as accurate as possible. Therefore, we will continue to
accept additional information and comments from all concerned
governmental agencies, the scientific community, industry, or any other
interested party concerning this finding.
References Cited
A complete list of references cited is available on the Internet at
http://www.regulations.gov and upon request from the Wyoming Ecological
Services Field Office (see ADDRESSES section).
Author(s)
The primary authors of this notice are the staff members of the
Wyoming Ecological Services Field Office.
Authority: The authority for this section is section 4 of the
Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).
Dated: May 16, 2011.
Rowan W. Gould,
Acting Director, Fish and Wildlife Service.
[FR Doc. 2011-13910 Filed 6-8-11; 8:45 am]
BILLING CODE 4310-55-P