[Federal Register Volume 76, Number 143 (Tuesday, July 26, 2011)]
[Proposed Rules]
[Pages 44547-44564]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-18645]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R1-ES-2010-0023; MO 92210-0-008-B2]
Endangered and Threatened Wildlife and Plants; 12-Month Finding
on a Petition To List the Giant Palouse Earthworm (Drilolerius
americanus) 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 the giant Palouse earthworm
(Driloleirus americanus) as threatened or endangered as petitioned, 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 the giant Palouse
earthworm 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 the giant Palouse earthworm or its habitat at any time.
DATES: The finding announced in this document was made on July 26,
2011.
ADDRESSES: This finding is available on the Internet at http://www.regulations.gov at Docket Number FWS-R1-ES-2010-0023. Supporting
documentation we used in preparing this finding is available for public
inspection, by appointment, during normal business hours at the U.S.
Fish and Wildlife Service, Washington Fish and Wildlife Office, 510
Desmond Drive SE., Suite 102, Lacey, WA 98503-1263; telephone 360-753-
9440; facsimile 360-753-9008. Please submit any new information,
materials, comments, or questions concerning this finding to the above
street address.
FOR FURTHER INFORMATION CONTACT: Ken Berg, Manager, Washington Fish and
Wildlife Office (see ADDRESSES). If you use a telecommunications device
for the deaf (TDD), please call the Federal
[[Page 44548]]
Information Relay Service (FIRS) at 800-877-8339.
SUPPLEMENTARY INFORMATION:
Background
Section 4(b)(3)(B) of the Endangered Species Act of 1973, as
amended (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 endangered or threatened,
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
On August 30, 2006, we received a petition dated August 18, 2006,
from three private citizens and three other parties (the Palouse
Prairie Foundation, the Palouse Audubon Society, and Friends of the
Clearwater) requesting that the giant Palouse earthworm (Driloleirus
americanus) (GPE) be listed as an endangered or threatened species
under the Act, and critical habitat be designated. The petition
included supporting information regarding the species' taxonomy and
ecology, distribution, present status, and causes of decline. On
October 9, 2007, we published a 90-day finding stating that the August
30, 2006, petition did not provide substantial scientific or commercial
information to indicate that listing the GPE may be warranted (72 FR
57273). On January 24, 2008, the petitioners filed a lawsuit in the
U.S. District Court, Eastern District of Washington against the U.S.
Department of the Interior and the Service challenging the ``not
substantial'' decision (Palouse Prairie Foundation et al. v. Dirk
Kempthorne, et al., No. 2:08-cv-0032-FVS). On February 12, 2009, the
District Court denied the Appellants' motion for summary judgment and
granted summary judgment in favor of the Service, upholding the October
9, 2007, determination. The U.S. Court of Appeals for the Ninth Circuit
affirmed the District Court ruling on June 14, 2010 (D.C. no. 2:08-cv-
00032-FVS).
History of the Current Petition
On July 1, 2009, we received a new petition dated June 30, 2009,
from Friends of the Clearwater, Center for Biological Diversity,
Palouse Audubon, Palouse Prairie Foundation, and Palouse Group of the
Sierra Club (petitioners) requesting that the GPE be listed as an
endangered or threatened species either in the entirety of its range,
or in the Palouse bioregion as a significant portion of its range, and
that critical habitat be designated under the Act. The petition clearly
identified itself as such and included the requisite identification
information for the petitioners, as required by 50 CFR 424.14(a). The
petition included information on the GPE's taxonomy, species
description, distribution, habitat, status, and potential threats. The
petition was accompanied by a letter from Samuel W. James, who stated
that he is ``the only earthworm taxonomist operating in the U.S.A.''
and has ``extensive experience in biodiversity of earthworms'' (2009 in
litt.), and included additional information about the GPE and potential
threats to the species. In an August 5, 2009, letter to the
petitioners, we acknowledged receipt of the petition and determined
that issuing an emergency regulation temporarily listing the species
under section 4(b)(7) of the Act was not warranted. We also stated
that, due to funding constraints in fiscal year 2009, we would not be
able to further address the petition at that time but that we would
further evaluate the petition when funding became available in fiscal
year 2010.
On July 20, 2010, the Service announced a 90-day finding on the
2009 petition to list the GPE as endangered or threatened under the
Act, and to designate critical habitat (75 FR 42059). Based on our
review, we found the petition presented substantial scientific or
commercial information indicating that listing the GPE as endangered or
threatened may be warranted. We initiated a review of the status of the
species to determine whether listing the GPE was warranted, and
requested scientific and commercial data, and other information,
regarding the species. This notice constitutes the 12-month finding on
the July 1, 2009, petition to list the GPE as endangered or threatened,
as petitioned.
Species Information
The GPE is one of about 100 native and at least 45 nonnative
earthworms described in the United States (Hendrix and Bohlen 2002, p.
802). However, very little is known about the species. The GPE was
first described by Smith in 1897, based on a collection near Pullman,
Washington. At the time of this collection, Smith stated: ``This
species is very abundant in that region of the country and their
burrows are sometimes seen extending to a depth of over 15 feet''
(Smith 1897, pp. 202-203). His writing is based on second-hand
information provided by R.W. Doane of Washington State Agricultural
School (now Washington State University) in Pullman, Washington, which
does not offer numerical or geographical context for his use of the
terms ``very abundant'' or ``that region of the country.'' This burrow
depth characterization has not been confirmed or contradicted by any
subsequent field work.
Early descriptions indicate the GPE can be as long as 3 feet (ft)
(0.9 meters (m); Smith 1897, p. 203). Reports in the popular literature
of GPEs up to 3.3 ft (1 m) in length (Science Daily 2006, p. 1; Science
Daily 2008, p. 1) have not been confirmed, and collections suggest that
specimens are more moderate in size (approximately 6 to 8 inches (in)
(15.2 to 20.3 centimeters (cm)) in length) (Smith 1937, p. 161; Science
Daily 2006, p. 1; Science Daily 2008, p. 1).
Taxonomy and Species Description
The Service accepts the current taxonomic classification of the GPE
(Subclass--Lumbricina; Superfamily--Megascolecoidea; Family--
Megascolecidae; Genus--Driloleirus; Species--americanus) (Smith 1897,
p. 203; Fender and McKey-Fender 1990, p. 372; Fender 1995, pp. 53-54).
While the naming conventions of the GPE have changed over time
(Megascolides americanus in 1897 (Smith 1897, p. 203) changed to
Driloleirus americanus by 1990 (Fender and McKey-Fender 1990, p. 372),
there is no information provided in the petition or in our files that
would indicate scientific disagreement about its taxonomic
classification as a species. Adult specimens in the Driloleirus genus
are generally distinctive, but identifying to the species level
requires expert morphological analysis, including dissection or DNA
evidence. Both methods take time, and there are few species experts. It
is difficult to identify juvenile earthworm species, because they have
no clitellum (a glandular section in the body wall, similar in shape to
a saddle). The clitellum is a
[[Page 44549]]
key morphological difference for determining many species, and juvenile
earthworm coloration can also vary, depending on soil type. Newly
hatched earthworms are even more difficult to identify, and until DNA
analysis becomes a more available tool, earthworm identification
requires the examination of sexually mature individuals. Depending on
site conditions and growth, an earthworm would need to be 3 to 6 months
of age before being recognizable as being in the genus Driloleirus
(Johnson-Maynard 2011, pers. com.).
Distribution
Distribution of native earthworm species in the Pacific Northwest
is limited by several factors. Pleistocene glaciation covered nearly
the whole of Canada and the northern edge of the United States,
eliminating earthworms from the area covered with ice (Fender 1995, p.
54). Since the retreat of the glaciers, earthworms in the Lumbricidae
family have been able to colonize the ice-free areas in a few
centuries, although earthworm distribution in the Megascolecidae family
(to which the GPE belongs) stops near the terminal moraines (ridges of
rock, gravel and soil across valleys at the end glaciers or ice fields)
of the ice sheet. This may be because the megascolecids prefer fine-
textured soils, which are largely absent at the edge of Pleistocene
glaciation (Fender 1995, p. 55). Other barriers, including mountain
ranges and arid areas (Bailey et al. 2002, p. 26), have slowed
recolonization of the Columbia Basin.
At the time of the original description, in 1897, this taxon was
known only from the area around Pullman, Washington (Smith 1937, p.
157). The GPE was originally considered to be an endemic species (a
species native to a particular region), that uses grassland sites with
deep soil and native vegetation of the Palouse bioregion (Wells 1983,
p. 213; James 1995, p. 1; Niwa et al. 2001, p. 34). The Palouse
bioregion is an area of rolling hills and deep soil in southeastern
Washington and adjacent northwestern Idaho. More recently, this species
has also been found in Douglas-fir forests in the Palouse region
(Johnson-Maynard, September 21, 2010, in litt. p. 1; November 30, 2010,
in litt. p. 1), and on the eastern slope of the North Cascades
Mountains (Cascades) west of Ellensburg, Washington (Fender and McKey-
Fender 1990, p. 358). In 2010, the GPE was also documented in dry pine
forest habitat near Leavenworth, Washington (Johnson-Maynard 2010, p.
3, in litt.). This broader distribution, which is now known to include
Latah County (Idaho), Whitman County (Washington), Kittitas County
(Washington), and Chelan County (Washington), provides evidence that
the species may not be endemic to Palouse grasslands.
Confirmed GPE locations, and other potential GPE locations (DNA is
currently being analyzed for these specimens), are identified in Table
1. Two of the potential GPE collections are of particular interest: one
in shrub/grassland habitat near Chelan, Washington, and one in second-
growth forest habitat east of Moscow, Idaho (Johnson-Maynard 2010, pp.
1-2; November 30, 2010, in litt. p. 2). The DNA or morphology results
for these specimens are not yet available to enable identification to
the species level, but if these specimens are confirmed to be GPE, the
currently known distribution and habitat types documented for the
species will be expanded. One commenter provided a list of possible GPE
locations in the Palouse region (Hall 2010, in litt. pp. 2-3), but
acknowledged that the sites were not confirmed. Although these
anecdotal locality reports may be helpful in identifying areas for
future GPE surveys, they are not relevant to this finding.
Table 1--Locations and Characteristics of Collections of the GPE or Driloleirus Genus
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Vegetation and other
Site name/year County/State Positive ID as GPE site characteristics, Collector (sources) Survey methods, if
if known comments known
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Pullman, 1897? Latah, ID............. Yes.................. ...................... Collected by Doane. .....................
(Smith 1897, Gates
1967).
Pullman, 1931...................... Whitman, WA........... Yes.................. ...................... Collected by Svilha. .....................
(Smith 1937).
Pullman, 1978...................... Whitman WA?........... Yes.................. Beneath hawthorn Collected by Fender. .....................
thicket. (Wells et al. 1983,
p. 213, credited to
Fender). One mile
east of Pullman.
Hwy 95/195, 1978................... Whitman, WA........... Yes.................. ...................... Collected by Fender. .....................
(Wells et al. 1983,
p. 213; credited to
Fender). Follow-up
visit by Johnson-
Maynard and Fender
in 2006 showed
habitat
significantly
degraded (Johnson-
Maynard November 20,
2010, in litt, p. 1).
Moscow Mountain, 1988.............. Latah, ID............. Yes.................. Douglas fir forest; Collected by Johnson .....................
Under the moss and and Johnson.
litter layer of a (Palouse Prairie
forested site. Foundation 2006;
Johnson-Maynard,
September 21, 2010,
in litt. p. 1).
[[Page 44550]]
Ellensburg, pre-1990............... Kittitas, WA.......... Yes **............... ...................... Collected by Fender. .....................
(Fender 1995; James
2000). ** Specimen
in poor shape, but
reflects properties
of GPE (Fender Sept.
14, 2010, in litt.
p. 1; Fender, Sept.
30, 2010, in litt.
p. 10; Johnson-
Maynard 2011, Pers.
Comm.).
Smoot Hill, 2005................... Whitman, WA........... Yes.................. Native Palouse prairie Collected by Characterized
remnant, some shrubs; S[aacute]nchez-de earthworm
25% slope, Northwest Le[oacute]n. populations in two
aspect, 2,723 feet (S[aacute]nchez-de grassland types
elevation; Soil: silt Le[oacute]n and (native prairie and
loam, gravelly sandy. Johnson-Maynard CRP) in Latah
2009, p.1398; County, ID, and
Johnson-Maynard Whitman County, WA.
November 30, 2010 in Conducted surveys in
litt. p. 2-3 ). May and June of 2003
Found during 2-year through 2005.
survey that included Methods: 5 measured
remnant prairie and pits randomly
Conservation Reserve located and
Program (CRP) excavated at each
grasslands in site and earthworms
Palouse. were sampled by hand
sorting, then
classified to
species.
Paradise Ridge, 2008............... Latah, ID............. Yes.................. Palouse prairie, some Collected by Umiker .....................
shrubs; 30% slope; and Robertson.
Southwest aspect; (Science Daily 2008,
3,527 feet elevation; Johnson-Maynard
blue bunch November 30, 2010,
wheatgrass, Idaho in litt. p. 2-3;
fescue, snowberry, Hill, 2010 in litt.
non-native grasses; pp. 2-3; Johnson-
Soil: Loam, high Maynard, September
content of gravel. 21, 2010, in litt.
p. 1; Johnson-
Maynard 2010 p. 2-
3). Determined to be
GPE based on
location and partial
specimen.
Paradise Ridge, 2010............... Latah, ID............. Yes. Identified by Palouse prairie, same Collected by Xu and 2010 GPE specimens
James. as above. Umiker. (Johnson- were collected with
Maynard, November electroshocker.*
30, 2010, in litt. Handsorting
p. 2). Adult GPE conducted at the
found at a privately same time did not
owned prairie result in the
remnant near Moscow, collection of GPE
Idaho, 2008 and 2010 (Johnson-Maynard
Paradise Ridge sites December 21, 2010 in
less than 50 feet litt. p. 2). *Use of
from each other. electrodes and a
Nearby location generator to direct
surveyed in 2005 electric current
with no GPE found. into the soil.
East of Moscow, ID, 2010........... Latah, ID............. Pending.............. Secondary growth Collected by: ? .....................
forest (Douglas fir). (Johnson-Maynard,
November 30, 2010,
in litt. p. 2).
Sample too degraded
for morphological
description;
currently analyzing
DNA.
Leavenworth, 2007.................. Chelan, WA............ Pending.............. Open forest, savanna; Collected by .....................
Relatively open resident, initially.
Ponderosa pine (Science Daily 2008,
forest. Compacted Johnson-Maynard
area covered with 2010, pp. 3-4
gravel soil. Johnson-Maynard
November 30, 2010,
in litt. p. 2.)
Driloleirus genus;
Currently analyzing
DNA.
[[Page 44551]]
Leavenworth, 2010.................. Chelan, WA............ Yes. Adult examined Ponderosa pine, Collected by Xu and Follow-up surveys
by Fender. Arrowleaf baslamroot/ Umiker. (Johnson- specific to
mule's ear, annual Maynard 2010 p. 2- determining
grasses; South 4). Multiple Driloleirus species
aspect, 27% slope; hatchling specimens-- and soil and site
1,846 feet elevation; will analyze one characteristics.
Soil: sandy loam. injured hatchling Survey conducted in
for DNA. November, 2010. Soil
was excavated from
one large pit
(approximately 60 cm
by 60 cm) at each
site. Soil was hand-
sorted and all
earthworms removed
and counted. One
sample was collected
from each site for
DNA analysis.
Near Camas Meadows (near Chelan, WA............ Pending.............. Arrowleaf balsamroot, Collected by: .....................
Leavenworth), 2010. scattered ponderosa Fleckenstein
pine. (Johnson-Maynard
December 22, 2010 in
litt. p. 2) Smaller
adult, will analyze
DNA.
Chelan, 2010....................... Chelan, WA............ Pending.............. Grasses, Arrowleaf Juvenile found--will Follow-up surveys
balsamroot, analyze for DNA specific to
sagebrush, sparse (Johnson-Maynard determining
ponderosa pine 2010, p. 2-4). Driloleirus species
nearby; ~38% slope, and soil and site
South aspect; 2,057 characteristics.
feet elevation; Soil: Survey conducted in
gravelly sandy loam. November, 2010. Soil
was excavated from
one large pit
(approximately 60 cm
by 60 cm) at each
site. Soil was hand-
sorted and all
earthworms removed
and counted. One
sample was collected
from each site for
DNA analysis.
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Table 1 identifies confirmed GPE and potential GPE locations (at
this time just identified to Driloleirus genus; DNA analysis is
pending), and information on survey methods for each collection where
available. While negative survey data are important to understand the
distribution of any species, the Service found little information on
surveys with negative results in the Palouse, and no information on
negative surveys outside of the Palouse. The available information on
negative survey results is presented in Table 1.
Earthworms are not randomly distributed in the soil (Guild 1952, as
referenced in Edwards and Lofty 1977, p. 127), and some are difficult
to detect. Factors that influence this non-random distribution could
include: (1) Physical and chemical characteristics of the soil; (2)
food availability; (3) the reproductive potential and dispersal
capabilities of the species; or (4) interactions between these factors
(Murchie 1958, as referenced in Edwards and Lofty 1977, p. 127).
Earthworms also occur in patchy distributions, which make it difficult
to determine population demographics (Whalen 2004, pp. 143, 148,
Umicker 2009, p. 187). Edwards and Bohlen (1996, p. 90) stated that
assessments of size, distribution, and structure of earthworm
populations are difficult because numbers change with season,
demography, and vertical distribution in the substrate.
In his letter submitted with the petition, James (2009 in litt. p.
2) states that a reasonable and sufficient effort has been made to find
the GPE in a variety of habitats within its presumed range, and that
these efforts have failed except in very rare instances in natural or
little-disturbed vegetation. James also stated that the Washington
State University team surveyed many locations (most importantly in
agricultural lands), looking for large burrows that may indicate the
presence of large earthworms, but only found Lumbricus terrestris (the
common night crawler), an invasive species (James 2009, in litt. pp. 2-
3). However, recently collected and confirmed specimens that have been
documented in forested habitats and on the eastern slope of the Cascade
Mountains in Washington (Table 1) indicate that survey efforts for the
GPE to date have not been adequate to establish its distribution or the
diversity of habitat types in which it occurs. Therefore, we believe
the petitioners' assumptions regarding the presumed distribution of the
GPE are likely erroneous.
Fauci and Bezdicek's study (2002, pp. 258-259) compared nonnative
lumbricid earthworm distribution in the Palouse region of eastern
Washington and northern Idaho. In the spring of 1999, they surveyed 46
sites in the Palouse, including sites in agricultural fields with a
history of conservation tillage, areas next to waterways, and perennial
vegetation areas along road rights-of-way or on old homesteads. Survey
methods included digging six spades of soil in a 10-square-meter area,
then hand-sorting and examining the soil. Additional samples were taken
if immature worms were found to ensure adults for identification.
Although the results for the GPE were negative, the Fauci and Bezdicek
survey was not designed to specifically find this species. In addition,
survey protocols have not yet been developed for the GPE; therefore, it
is uncertain the protocol used in this study would have found GPE, if
present. If reports that the GPE lives in burrows more than 15 feet
deep are correct, the spade sampling method used by Fauci and Bezdicek
would appear to be inadequate to confirm the species' absence.
[[Page 44552]]
Other negative earthworm surveys in the Palouse area were also not
specifically designed to find the GPE. Umiker et al. (2009, pp. 184-
185, 187) compared soil characteristics, cropping practices, and
earthworm densities in 24 agricultural fields in the Palouse, but did
not identify the earthworms to species level in that study (p. 187).
However, adult Driloleirus earthworms are distinctive enough that they
likely would have been documented, had they been collected. Juvenile
Driloleirus earthworms, on the other hand, are not distinctive
(Johnson-Maynard 2011, pers. com.), and hence could have been missed in
this survey. Johnson-Maynard et al. (2007, p. 338) compared earthworm
dynamics and soil properties in conventionally tilled and no-till
agricultural fields on one research farm in the Palouse, and found only
the nonnative southern worm (Aporrectodea trapezoids) (p. 340). Smetak
et al. (2007, p. 161) investigated earthworm population density in
urban settings in Moscow, Idaho; no native earthworm species were
collected (p. 166). Nevertheless, while the negative survey data are
interesting, in that the GPE has not been detected in agricultural
fields or urban areas to date, coupled with information in Table 1,
these data demonstrate how geographically limited the known survey
efforts have been.
It is apparent that additional GPE surveys are needed to determine
the range, habitat preference, and life history of this species,
particularly in light of the recent confirmation of the species near
Leavenworth, Washington, in forested habitat. James (2000, p. 5)
acknowledges there have been a limited number of earthworms collected
in the Columbia basin, which includes the eastern slope of the Cascade
Mountains and the Palouse area, and only a small portion of potential
habitat has been surveyed. In addition to limited survey efforts, this
species is difficult to detect. Fender (September 14, 2010, in litt. p.
1) noted that Driloleirus species can at times be found near the
surface during suitable survey conditions, but if conditions are dry
they may be undetectable. Johnson-Maynard (September 21, 2010, in litt.
p. 2) noted that one Palouse site had negative survey results for
native earthworms in 2005, but later sampling in 2010 detected one
adult GPE at the same site. The Xerces Society stated that due to the
difficulty in detecting the Oregon giant earthworm (Driloleirus
macelfreshi) (a similar species in the same genus), abundance estimates
have not been made, and the species' status and threats cannot be
determined until an effective survey protocol is developed and tested
(Xerces Society 2009, p. 3).
Due to the difficulty in surveying for the GPE, the Idaho
Department of Fish and Game, the Service, and others have contributed
resources to the University of Idaho to develop appropriate survey
protocols to address the scientific challenges associated with GPE
surveys (Groen 2010, in litt. p. 2; Johnson-Maynard 2010, in litt. p.
2; Science Daily 2008, p. 2). Staff at the University of Idaho,
including Johnson-Maynard and others, are currently working to develop
and refine sampling methods and strategies, including a soil
electroshocking technique that appears to be promising.
In summary, the level of survey effort for the GPE has been low,
the species is difficult to detect, and effective survey methods are
still being developed. There is a lack of survey data, and large
geographic and taxonomic gaps in our knowledge (Fleckenstein 2011, in
litt. p. 1). Researchers have only recently begun to look more broadly
for the species including localities along the eastern slope of the
Cascades. However, the GPE has now been documented in dry forest
habitats, which provides further evidence that the complete range and
distribution of the species is presently unknown, but are likely
broader than the area identified by the petitioners.
Habitat
Habitat requirements for the GPE are not well understood. The
original descriptions by Smith (1897, 1937) do not present any
descriptive information about the habitat where the specimens were
initially collected. The GPE was originally thought to be a Palouse-
region grassland species, and several specimens have been found in
Palouse grassland remnants (Table 1; S[aacute]nchez-de Le[oacute]n and
Johnson-Maynard 2009, p. 1393; Science Daily 2008, p. 1; Johnson-
Maynard September 21, 2010, in litt. pp. 1-2; Johnson-Maynard, November
30, 2010, in litt. p. 2-3; Jensen 2010, in litt. p. 6). Wells et al.
(1983, p. 213) stated that Fender collected specimens under hawthorn
thickets; Johnson-Maynard (September 21, 2010, in litt. p. 1) described
the vegetation type at Johnson and Johnson's Moscow Mountain site as
Douglas-fir forest.
There is limited specific information on the habitat type
associated with the GPE collected near Ellensburg, Washington. Fender
and McKey-Fender (1990) described the location as ``in the hills west
of Ellensburg,'' and they described the GPE range at this locality as
extending into ``treeless areas'' (pp. 358, 366). The GPE was not
collected in recent surveys conducted in agricultural and urban
locations in Latah County, Idaho (Johnson-Maynard et al. 2007, p. 340,
Smetak et al. 2007, p. 166; Umiker et al. 2009, p. 187), and Whitman
County, Washington (Fauci and Bezdicek, 2002 p. 257). Vegetation and
soil characteristics of confirmed and potential GPE sites are described
above in Table 1, where that information was available. S[aacute]nchez-
de Le[oacute]n and Johnson-Maynard (2009, p. 1394; Petition, p. 5)
observed that remaining prairie remnants in the Palouse are often steep
or rocky, or contain shallow soil, and, therefore, may be less suitable
for earthworms (S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009,
pp. 1394, 1398; Petition, p. 5). However, Johnson-Maynard (2010, pp. 2-
3) noted that soils at the Paradise Ridge site near Latah, Idaho, had a
high gravel content, suggesting that the GPE may be able to exist in
soil types that would not be expected to be preferred habitat for most
earthworms. She further noted that past Driloleirus samples provided by
a landowner near Leavenworth, Washington, were obtained from a
compacted area covered with gravel. Johnson-Maynard (2010, pp. 3-4)
described the confirmed GPE collection site near Leavenworth,
Washington, as Ponderosa pine forest with an understory of Balsamorhiza
sagittata (arrowleaf balsamroot) and annual grasses. Although the GPE
has also been documented in forests on the eastern slope of the
Cascades and in Douglas-fir forests in the Palouse, significant
uncertainties exist as to whether the species occurs in specific types
or ages of forests, occurs in previously logged forests, or may be
habitat-limited because of elevation or other site characteristics.
Biology
Earthworms are generally divided into three life-history strategies
based on their habitat use: epigeic, endogeic, or anecic (Bouche 1977,
as referenced in James 2000, p. 2; Edwards and Bohlen 1996, pp. 113-
115). Epigeic worms live near the ground's surface and consume organic
litter on and near the surface. Endogeic worms (which the petitioners
currently believe the GPE to be (James 2009, in litt. p. 3)): (1) Live
in the upper layers of mineral soil, (2) consume organic material in
the mineral soil or at the soil-litter interface, and (3) are often
pale in appearance (Edwards and Bohlen 1996, p. 114). Anecic worms,
which the petitioners initially believed the GPE to be (James 2009, in
litt. p. 3), and we believe the GPE to be based on
[[Page 44553]]
the prevailing evidence, live in deep, semi-permanent burrows and move
to the surface to feed on fresh plant litter. Anecic earthworms are the
largest and longest lived of the three earthworm types (James 2000, p.
2; 1995, p. 6), and transport fresh plant material from the soil
surface to subterranean levels. Deep-burrowing anecic earthworms
usually produce castings on the surface near exits to their burrows
(Edwards and Bohlen 1996, p. 198). GPE castings were observed at the
Leavenworth, Washington, study area (Johnson-Maynard 2010, p. 2).
James (2009, in litt. p. 3) concluded that, based on the lack of
pigmentation and information indicating that the species is not
associated with surface castings, the GPE ``is probably an endogeic,
meaning living entirely in the soil, on soil resources consisting of
organic matter in varying stages of decomposition.'' He also states
that deep burrow depths would be useful in avoiding dry soil conditions
common in late summer within the range of the species (September 3,
2010, in litt. p. 1). Fender (September 14, 2010, in litt. p. 1) thinks
deep soils would be helpful to survival and sees no reason to doubt the
earlier descriptions of burrowing depths.
Characterizing earthworm life histories within one of three life-
history strategies may not be entirely instructive, because some
species may exhibit a combination of characteristics (Bouche 1977, as
referenced in Edwards and Bohlen 1996, p. 113). However, understanding
an earthworm species' life history is important for evaluating
potential threats, the pathways that expose them to threats, and how
they might respond.
As stated earlier, James (2009, in litt., p. 3) initially
speculated that the GPE was an anecic species, but now believes the
species is probably an endogeic earthworm. He indicated that this
conclusion is based on seeing a GPE specimen and learning more about
the genus; if the GPE lacks pigmentation in the head and does not
defecate at the surface (i.e., leave castings), it is highly unlikely
to have an anecic life-history strategy. We have no information
indicating whether James has conducted field surveys for this
particular earthworm species; however, his current opinion appears to
be inconsistent with the existing literature, descriptions of GPE
burrowing depths described in the literature, and field observations of
castings by researchers at the Leavenworth, Washington, GPE location
(Smith 1897, pp. 202-203; Fender and McKey-Fender 1990, p. 364; James
2000, p. 5; Johnson-Maynard 2010, p. 2).
In our 2010 90-day finding (75 FR 42059), we solicited scientific
information on the GPE's endogeic or anecic life-history strategy to
inform our status review. Johnson-Maynard (in litt. 2010, p. 2) stated
that the GPE is likely anecic, based on her surveys at locations near
Leavenworth, WA. In those studies, the GPE was associated with pores
leading down into unconsolidated parent material, and surface castings
were observed, which are indicative of a deep-burrowing species.
Johnson-Maynard has conducted or been involved with a number of field
surveys where GPE specimens were collected (see Table 1 above).
Therefore, based on the best available scientific information, field
observations, and the existing literature, we believe the prevailing
evidence indicates the GPE is an anecic earthworm species, although we
acknowledge that there are still significant uncertainties regarding
its biological requirements.
In summary, the current understanding regarding the life cycles of
even quite common earthworms is inadequate and requires more study
(Edwards and Lofty 1977, p. 68), and there are many species about which
little is known (Edwards and Bohlen 1996, p. 46). Accordingly, there
are significant scientific uncertainties regarding the biology,
distribution, habitat, and population trends of the GPE. The GPE's
distribution has been documented to include areas within the Palouse
bioregion, and areas within the eastern slope of the Cascade Mountains
in Washington. We do not know whether there are other occupied sites
between or outside of these locations, as few surveys have been
conducted, the species is difficult to survey for, and survey methods
are still being developed.
Documented habitat types used by the GPE in the Palouse bioregion
include native grasslands and Douglas-fir forest. In addition, the GPE
location near Leavenworth, Washington, is described as dry Ponderosa
pine forest. There is very little specific information on habitat type
at the GPE location west of Ellensburg, Washington. The Driloleirus
earthworm species recently collected near Chelan, Washington, and east
of Moscow, Idaho, are being identified (see Table 1 above). If these
specimens are confirmed to be the GPE through DNA or other analysis,
the species' range and diversity of habitat types used would be
expanded.
Summary of Information Pertaining to the 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 this finding, information pertaining to the GPE in
relation to the five factors provided in section 4(a)(1) of the Act is
discussed below. In addition, in making this 12-month finding on the
petition we considered and evaluated the best available scientific and
commercial information.
Given the paucity of information on GPE, surrogates may be useful.
The petitioners claim that it is appropriate to use other earthworms as
surrogates to determine effects to the GPE, provided they are
biologically and ecologically similar (Sappington et al. 2001, p. 2869;
Caro et al. 2005, p. 1821; Petition, p. 10). In some instances, the use
of surrogate species (such as other earthworms) may be helpful in
evaluating potential effects to the GPE, provided the appropriate
scientific controls and precautions are taken. Caro et al. (2005, p.
1821) states ``for substitute species to be appropriate, they should
share the same key ecological or behavioral traits that make the target
species sensitive to environmental disturbance and the relationship
between populations' vital rates and disturbance levels should match
that of the target; these conditions are unlikely to pertain in most
circumstances and the use of substitute species to predict endangered
populations' responses to disturbance is questionable.'' The Oregon
giant earthworm (Driloleirus macelfreshi) is in the same genus, and is
believed to construct permanent, deep, subsurface burrows (a
characteristic that indicates an anecic life-history strategy), and
could potentially be an appropriate surrogate. However, the status and
threats of this species cannot be determined until an effective survey
protocol is developed and tested (Foltz 2009, pp. 2-3). Therefore,
using it as a surrogate would provide little to no additional insight
into potential threats to GPE. No other relevant surrogate
[[Page 44554]]
species have been suggested or investigated.
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
Habitat Loss and Fragmentation
Historical information regarding potential habitat loss is
presented in the following discussion, for context. However, the focus
for purposes of our analysis and response to the petition is on current
and future habitat conditions, and whether the activities responsible
for those conditions present a threat to the GPE such that listing
under the Act is warranted.
As described in the 2010 90-day finding (75 FR 42061), the
petitioners claim that the GPE is threatened by habitat conversion,
loss, and fragmentation from agriculture and urban sprawl in the
Palouse region (Petition, pp. 1, 7). The petitioners cite
S[aacute]nchez-de Le[oacute]n and Johnson-Maynard (2009, pp. 1393-1394,
1398), who state that combined effects of land-use change, habitat
fragmentation, and competitive interactions have caused native
earthworm declines. James (2009, p. 1) stated that indigenous
earthworms are sensitive to habitat disturbance, and that to find
indigenous earthworms one must work in undisturbed or mildly disturbed
vegetation. Undisturbed vegetation is rare in the Palouse bioregion, as
the native grassland habitat has been reduced to less than 1 percent of
its pre-agricultural extent (Petition, p. 8; James 2009, p. 1; Noss et
al. 1995, p. 74).
Estimates of native habitat conversion in the Palouse bioregion
vary, but several studies indicate the conversion has been high: 99.9
percent of Palouse prairie habitats have been converted to agriculture
(Noss 1995, p. 74); 94 percent of the grasslands and 97 percent of the
wetlands in the Palouse bioregion have been converted to crop, hay, or
pasture (Black et al. 1998, pp. 9-10); 21 percent of previously
forested lands have been converted to agriculture or urban uses
(Gilmore 2004, p. 3); and less than 1 percent of the original
bunchgrass prairie habitat remains (Donovan et al. 2009, p. 1).
However, comments on the 90-day finding noted that habitat loss in the
Palouse due to agriculture happened historically and is not currently
occurring. Much of the prairie was converted to farms by 1910, and much
of the urban growth around the Pullman area occurred on farmland, not
remaining prairie fragments (McGregor 2010, in litt., p. 2; McGregor
1982, p. 109). However, habitat conversion in the Palouse may still
occur, as neither Latah County, Idaho, nor Whitman County, Washington,
have ordinances to prevent native habitat conversion (Latah County
Board of Commissioners 2010, pp. 1-27; Whitman County 2010, pp. 1-76).
The petition identified several locations in the Palouse area that
contain prairie remnants (Petition, p. 5). A study of four prairie
remnants and adjacent Conservation Reserve Program (CRP) fields was
carried out by S[aacute]nchez-de Le[oacute]n and Johnson-Maynard (2009,
pp. 1393, 1395; Petition, p. 4). In that study, the researchers
collected one GPE, and commented that many remaining prairie remnants
are not suitable for tillage because they are often steep or rocky, or
contain shallow soil (2009, p. 6; Petition, p. 5). They also
hypothesized that prairie remnants may not be the preferred habitat for
the GPE due to shallow rocky soil. They described the GPE collection
site at Paradise Ridge near Latah, Idaho, as having a high gravel
content (Johnson-Maynard 2010, pp. 2-3). They acknowledged that
sampling challenges could bias survey information on the GPE, and
cautioned that hand-sampling methods may underestimate abundance of
anecic species (S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009,
p. 1399).
There is no baseline (i.e., pre-agriculture) density and
distribution information on the GPE, and there are significant
challenges associated with surveying for this species. These
challenges, coupled with the fact that earthworms have patchy
distributions (Guild 1952, as referenced in Edwards and Lofty 1977, p.
127; Murchie 1958, as referenced in Edwards and Lofty 1977, p. 127;
Whalen 2004, pp. 143, 148; Umicker 2009, p. 187), preclude our ability
to correlate land use impacts with GPE abundance, based on the best
available information. The GPE has been documented in both the Palouse
bioregion and on the eastern slope of the Cascade Mountains, near
Ellensburg and Leavenworth, in central Washington (see Table 1 above).
There is little descriptive information about the habitat associated
with the GPE that was collected near Ellensburg; it isn't clear whether
the location is grassland or a different habitat type, and the specific
location is uncertain. James (2009 in litt., p. 2) speculated the
Ellensburg site collection is a relict of a distribution that must have
been more or less continuous at one time, but due to climate change and
increased aridity has now become fragmented. Fender and McKey-Fender
(1990) described the locality as being ``in the hills west of
Ellensburg,'' and noted that the range of the GPE extends into
``treeless areas'' (pp. 358, 366). A report by Adolfson Associates
(2005, p. 1) was presented as evidence of urban sprawl being a threat
to GPE habitat. However, this report was limited to areas within the
City of Ellensburg, Washington boundary, and is not particularly
instructive in terms of correlating future urban development with loss
of GPE habitat because pre-development density or distribution or both
in that area are unknown. The petitioners also claim the grasslands
around Ellensburg have been extensively modified by agriculture,
similar to the Palouse bioregion (Adolfson Associates 2005, p. 2;
Petition, p. 8; James 2009, in litt., p. 2). However, the best
available information is insufficient to determine or infer how or
whether the GPE has been impacted by habitat loss and fragmentation in
this area, because we have no baseline information with which to
correlate land use modification with GPE abundance.
The best available scientific information is also inconclusive as
to whether the GPE occurs in a certain forest type or age, or whether
the species occurs in a broad variety of habitats. The GPE site near
Moscow, Idaho, is in Douglas-fir forest habitat, and the Leavenworth,
Washington, site is in dry ponderosa pine forest. Quigley et al. (1996,
p. 54) stated that in the Columbia Basin, the total area in forest has
remained relatively constant during the last two centuries, and broad
indicators of sustainability indicate that Basin forest acreage and
inventory volumes are relatively constant. If the GPE is a forested
habitat generalist, it could be stable in forested locations; however,
if it requires a forest of a specific type or age it may or may not be
impacted by habitat loss, depending on the type of development activity
involved. In either case, the available scientific evidence does not
address that uncertainty.
In summary, the GPE's current and historical population size,
distribution, and range of habitat types used are unknown. Based on
recent collections, the GPE's range outside of the Palouse region has
been expanded and now includes portions of the eastern slope of the
Cascade Mountains. The GPE has also been documented in both grassland
and forested habitats in the Palouse. However, survey efforts have been
limited, and sampling protocols are still being developed to improve
researchers' ability to detect the species during field investigations.
While habitat conversion may occur and there may be local impacts, the
GPE range is much wider than previously known and includes more diverse
habitats than previously
[[Page 44555]]
known. Because we cannot identify the full extent of the GPE's range or
the varieties of habitat types it may use, we are unable to correlate
habitat conversion with GPE abundance. Therefore, for the reasons
stated above, the best available scientific information does not
indicate current or future habitat loss or fragmentation represents a
threat to the species.
General Impacts to Soil Characteristics
The petitioners present several claims in their petition, each of
which has been evaluated and addressed below. They claim that
earthworms or their grassland habitats are influenced by soil
disturbance, tillage, traffic, food sources, chemical and pesticide
residues, and soil microclimate (Jennings et al. 1990, p. 75; Edwards
and Bohlen 1996, pp. 283-289; Edwards et al. 1995, pp. 200-201; USDA-
NRCS 2001, p. 2; Petition, p. 10). Moisture, temperature, and food
availability influence earthworm populations in general, and earthworms
need the organic matter found in the topsoil that agriculture removes
(James 2000, pp. 1-2; Petition, p. 11). Bare soil can increase the
effects of flooding, drought, or other weather conditions due to the
lack of vegetation that buffers soil from extreme moisture, dryness,
and temperature fluctuations. These conditions can temporarily or
permanently make soils unusable by earthworms (James 2000, pp. 1-2;
Petition, p. 11). James (2009, in litt., p. 1) stated that earthworms
are highly sensitive to habitat disturbance, such as forest clear
cutting or conversion of any habitat to agriculture, and the native
earthworms are generally destroyed by any type of drastic and sudden
habitat modification. One commenter stated there may have been long
periods of bare soil historically in the Palouse region, but seeding
and fertilizing technology improvements now enable farmers to prepare
seedbeds with minimal disturbance (McGregor 2010, in litt., p. 2).
James also stated, ``when seeking the indigenous earthworms, it is
almost always a complete waste of time to work in anything but
undisturbed or mildly disturbed stands of vegetation'' (James 2009, in
litt., p. 1). GPE have been found in forested locations, but it is
unknown whether these are previously disturbed habitats.
We acknowledge that soil disturbance has occurred and may still be
occurring in GPE habitat. However, we currently have no information
linking soil disturbance with GPE presence or absence. Survey efforts
for GPE have been limited, and sampling protocols remain to be
developed. Until we have a better understanding of the species'
distribution and habitat information, we are unable to determine with
reasonable confidence whether the GPE uses disturbed or undisturbed
habitats, or both. Therefore, the best available scientific information
does not indicate soil disturbance is a threat to the GPE.
Soil Compaction
The petitioners claim that soil compaction from farm machinery or
other activities can affect earthworms by making burrowing and feeding
more difficult (James 2000, p. 9), by decreasing soil pore size and
thereby decreasing nutrient retention and changing the soil food web
(Niwa et al. 2001, pp. 7, 13), or by favoring nonnative earthworms that
prefer course soils rather than the fine soils apparently preferred by
the GPE (Fender and McKey-Fender 1990, p. 364; Petition, p. 11).
Johnson-Maynard (September 21, 2010, in litt., pp. 2-3) noted that the
effects of soil compaction on earthworm density can vary based on the
species' ecological strategy (i.e., anecic versus endogeic); larger
species, such as anecic earthworms, have been found to be less
sensitive to soil compaction than smaller species (Cluzeau et al. 1992,
p. 1661) and may be more abundant in compacted areas compared to non-
compacted areas (Cuendet 1992, p. 1467). Fender (1995, p. 57) has often
found other Argilophilini worms (a tribe of native Pacific Northwest
earthworms that includes the GPE) in compacted trails; Capowiez et al.
(2009, p. 214) notes that our current knowledge of the sensitivity of
earthworms to compaction is limited. In addition, the assumption that
compaction would favor exotic species over native species due to their
preference for finer-textures soils is invalid; while compaction does
impact total porosity and pore size distribution, it does not alter
soil texture (Johnson-Maynard, September 21, 2010, in litt., p. 3).
Johnson-Maynard states that generalizations such as those presented by
the authors of the 2009 petition, suggesting that compaction favors
nonnative species, should be interpreted with caution (Johnson-Maynard,
September 21, 2010, in litt., p. 3). In addition, survey efforts for
the GPE have been limited, and sampling protocols remain to be
developed. Until we have a better understanding of the species'
distribution and habitat information, we are unable to determine with
reasonable confidence whether soil compaction is occurring in GPE
habitat, and if it is, whether it is resulting in a negative response
in the species. Therefore, the best available scientific information
does not indicate soil compaction is a threat to the species.
Soil Chemistry
The pH scale describes how acidic or basic a substance is, and
ranges from 0 to 14, with 7 being neutral, below 7 being acidic, and
greater than 7 being basic. The petitioners cite soil chemistry
effects, notably a reduction in soil pH from nitrogenous fertilizer
application, as having deleterious effects on earthworms (Ma et al.
1990, p. 76), and state that generally earthworms do not thrive in
soils with a pH below 5 (Petition, p. 11; Edwards and Lofty 1977, p.
234). However, the best available scientific information related to the
responses of earthworms to pH appears to both support and contradict
the petitioners' claim with regard to the GPE. Soil pH is a factor that
often greatly affects earthworm populations, both in numbers of
individuals and numbers of species. According to the Natural Resources
Conservation Service (USDA-NRCS 2001, p. 5), earthworms do not thrive
in soils with a pH below 5 (USDA-NRCS 2001, p. 2; Edwards and Lofty
1977, p. 234; Edwards and Bohlen 1996, p. 276). However, one Australian
study of tillage effects to one native anecic earthworm species
(Spencefiella hamiltoni) described the surface soil in the study area
as highly acidic (pH = 4.1), with the pH increasing (or acidity
decreasing) with depth (pH = 5.0 at 0.8 meters) (Chan 2004, p. 90).
Some earthworm species are intolerant of acid soil conditions, some are
tolerant, and others can tolerate wide ranges of soil pH (Edwards and
Bohlen 1996, p. 142). Because soil pH is related to other soil factors,
such as clay content, or cation exchange capacity (the ability to hold
plant nutrients), it is often difficult to establish a direct cause-
and-effect relationship between soil pH and the size of earthworm
populations (Edwards and Bohlen 1996, p. 144).
Fender (1995, p. 56) stated that Argilophilini worms appear to have
higher tolerance than lumbricids (nonnative earthworms, such as the
night crawler) for low pH (below 5, acidic) soils; high clay; and
resinous, low-nitrogen, plant litter. S[aacute]nchez-de Le[oacute]n and
Johnson-Maynard (2009, pp. 1397, 1399) found a significant negative
interaction between soil pH and mean earthworm density and mean
earthworm fresh weight. The nonnative southern earthworm (Aporectodea
trapezoids) was more abundant in CRP sites with lower pH values (pH 5.9
to 6.2) than prairie soils (pH 6.3 to 6.6) in a study of four paired
CRP and prairie remnant sites. Their data did not support their
hypothesis that native
[[Page 44556]]
earthworms would be dominant in prairie remnants and exotic earthworms
dominant in CRP set-aside lands (S[aacute]nchez-de Le[oacute]n and
Johnson-Maynard 2009, pp. 1398). In that study, one GPE was collected
during sampling at the Smoot Hill prairie remnant study site. In the
study, the prairie remnants' mean soil pH at depth was pH 6.3 (20-30
cm), pH 6.5 (10-20 cm), and pH 6.6 (0-10 cm), while in the CRP study
sites the mean soil pH at depth was pH 6.2 (20-30 cm), pH 6.0 (10-20
cm), and pH 5.9 (0-10 cm) (S[aacute]nchez-de Le[oacute]n and Johnson-
Maynard 2009, p. 1397). The researchers stated they were unsure whether
lower pH (more acid) in CRP sites correlated with some other non-
measured soil parameter, such as previous fertilizer applications and
resultant increased organic matter. They hypothesized the negative
relationship between earthworm density and soil pH could be a
reflection of a past land use rather than a direct effect of soil pH on
earthworms (S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009, p.
1399). Other studies in the Palouse region demonstrated the mean soil
pH in direct-seeded agricultural fields was pH 5.35, and in
conventional tillage fields pH 5.61 (Umiker et al. 2009, p. 184). One
commenter (McGregor 2010, in litt., p. 4) stated less than 0.5 to 1
percent of the soils sampled in the Palouse have pH levels below 5.
In summary, studies investigating relationships between earthworms
and soil pH indicate that earthworm response can vary with species,
location, life-history strategy, or other attributes. The best
available scientific information on this relationship for the GPE is
limited (e.g., to our knowledge, only the Smoot Hill study has
investigated the potential soil pH relationship). There is significant
uncertainty regarding the correlation between soil pH and GPE
occurrence or persistence, and insufficient data to identify pH cause-
and-effect relationships that might be limiting for the persistence of
this species. However, in the Palouse region, soil pH levels do not
appear to be so acidic (below pH 5) that they negatively affect
earthworms generally. Also, the GPE may be more tolerant to acidity
than some species of earthworms. In addition, the range of the GPE is
wider than previously known, and includes pine forests on the eastern
slope of the Cascades, although the full extent and type of forested
habitats occupied by the GPE are not yet known. Detailed soil
characteristics are not known for the GPE location near Leavenworth,
Washington. Accordingly, the best available information does not
indicate that changes in soil chemistry represent a threat to the GPE.
Tillage and Agriculture
The petition states that tillage removes the original topsoil,
which may reduce earthworm burrow densities, soil aeration, soil
infiltration rates, and the amount of organic matter available to the
GPE for forage (Petition, pp. 10-11). Literature cited by the
petitioners stated the original topsoil has been lost from 10 percent
of Palouse cropland, and 60 percent of cropland has lost 25 to 75
percent of its topsoil (Veseth 1986b, p. 2). The petition did not
present detailed information on agriculture activities in the
Ellensburg area, although the Adolphson Associates report (2005, pp.
14-22) presented with the petition includes maps and photographs
depicting areas converted to agriculture within the Ellensburg,
Washington, city boundaries.
The potential threats to the GPE from tillage and cultivation are
reduced food sources and burrow compaction, but would likely vary
depending on its life-history strategy. Annual crops put a small
fraction of their production into root mass (James 2009, in litt., pp.
3-4), whereas perennial prairie grasses put approximately 50 percent of
their annual production into roots, which provide resources for soil
invertebrates (including endogeic earthworms). Endogeic earthworms,
which the petitioners assert the GPE to be (James 2009, in litt., pp.
3-4), would probably be more susceptible to agricultural activities
that reduce soil organic matter, based on their need for organic matter
as a food source. However, anecic earthworms use surface litter as a
food source, and the best available scientific information supports the
GPE being an anecic earthworm species. In either case, surveys to date
in the Palouse have not documented the GPE in either agricultural
fields or CRP lands (Fauci and Bezdicek, 2002, p. 254; S[aacute]nchez-
de Le[oacute]n and Johnson-Maynard 2009, p. 1393; Johnson-Maynard et
al. 2007, p. 340). Therefore, we have no information indicating that
the GPE would be exposed to reduced soil organic matter or reduced
surface litter caused by ongoing cultivation in the Palouse region.
One Australian study demonstrated that 3 years of tillage reduced
earthworm burrow density by nearly 90 percent (Chan 2004, p. 89;
Petition, p. 10), which reduced the maximum infiltration rate of the
soil and significantly increased the likelihood of runoff and erosion.
Chan's study (2004, p. 90) compared tillage effects to soil
infiltration by monitoring burrow density for the North Auckland worm
(Spenceriella hamiltoni), an anecic member of the Megascolecidae (in
the same family as the GPE), under three conditions: no-till (crops
drilled directly into ground with a special slit drill), conventional
one-pass, and conventional two-pass tilled agriculture (Chan 2004, p.
94). The effect of tillage on earthworm abundance is usually negative
because tilling causes physical damage and burial of residues, although
tillage could also increase the abundance of some earthworm species due
to increases in food supply by incorporation of residues into the soil
(Chan 2004, p. 90). In this study, tillage was found to decrease burrow
density and water infiltration into the soil (Chan 2004, pp. 89, 94).
The author concluded that under cropping, preservation of earthworm
burrows can be achieved by adopting conservation tillage techniques
(Chan 2004, p. 96). Conservation tillage techniques generally involve
establishing crops in a previous crop's residues, which conserves water
and minimizes soil disturbance and erosion.
Johnson-Maynard (September 21, 2010, in litt., p. 2) discusses
studies in which tillage effects on earthworm density were found to be
dependent on the ecological grouping of earthworms in an area (i.e.,
anecic or endogeic). Chan (2001, pp. 179, 185-187) found in a 3-year
study that tillage had a strong negative impact on anecic species due
to a combination of direct damage, burial of residue (food source), and
destruction of earthworm burrows, while endogeic species were
positively affected in the short term due to their smaller size (less
physical damage) and increased availability of organic matter. In the
Palouse bioregion, tillage removes the original topsoil, which may
reduce earthworm burrow densities, soil aeration, soil infiltration
rates, and the amount of organic matter available to the giant Palouse
earthworm for forage (Veseth 1986b, p. 2; Petition, pp. 10-11). Edwards
and Bohlen (1996, p. 215) stated that earthworm populations were much
larger in soil that was manipulated using no-till methods. No-till
agriculture accounted for 14,563 acres (5,893 hectares), or roughly 5
percent of the total surveyed acreage in the Palouse in 1989, up from
the previous 5-year average (1984-1988) of 3 percent (Hall 1999, p.
15).
The GPE has been documented in the Palouse in remnant native
grassland and in Douglas-fir forests, and in ponderosa pine forest at
the Leavenworth site near Chelan, Washington. The GPE distribution is
wider than previously known, but its total distribution remains
uncertain because the species is very
[[Page 44557]]
difficult to detect, survey protocols are still being developed, and
the level of survey efforts within and outside of the Palouse area has
been very low. While there may have been historical impacts to the GPE
from agriculture in the Palouse, the magnitude of threats from those
activities is difficult to determine because we have no baseline
population or distribution information with which to make a comparison,
other than the anecdotal statement in Smith (1897, pp. 202-203). In
addition, to date the GPE has not been found in agriculture fields in
the Palouse, and we have no information that indicates the GPE is or
will be exposed to tillage and agriculture. Accordingly, the best
available information does not indicate that tilling and agriculture
represent a threat to the GPE.
Grazing
James stated that grazing degrades earthworm habitats, potentially
to the point of causing extirpation, and that soil compaction from
livestock grazing can affect earthworms by making burrowing and feeding
more difficult (James 2000, pp. 9-10). The petition also claims that
livestock grazing changes the quality and accessibility of detrital
material, decreasing organic matter available to earthworms through
conversion of herbage to partly digested clumps of organic matter
(James 2000, p. 9; Petition, p. 14).
The petitioners describe livestock grazing as a pervasive land use
in the range of the GPE. James (2000, p. 9) stated: (1) Livestock
grazing can cause soil compaction, thereby making burrowing and feeding
more difficult for earthworms; (2) effects are variable by earthworm
species or habitat type (or both); (3) large earthworm species are less
heavily impacted by grazing; and (4) ``without further knowledge about
native earthworms and the presence or absence of earthworms in lands
subject to grazing in the Columbia River basin assessment area, it is
of little use to speculate further.'' Cluzeau et al. (1992, pp. 1661,
1663) demonstrated intensive trampling by cattle can reduce earthworm
densities, particularly for smaller species and those living near the
surface. No specific information was provided by the petitioners
regarding the extent of livestock grazing impacts in the Palouse or
Ellensburg areas. However, several individuals (Field 2010, in litt.,
p. 2; Jensen 2010, in litt., p. 6) commented that grazing can benefit
some earthworms through increasing organic matter and plant species
diversity (Dorsey et al. 1998, p. 2; Taylor and Neary 2008, p. 2). We
cannot assess the distribution of the GPE in relation to grazing
activities or grazing intensity because the species' range is unknown,
but is wider than previously documented, there have been very few
surveys, and the habitats used by the species are more variable than
previously known. However, the best available information indicates
grazing can sometimes benefit earthworms and larger species like the
GPE may be less impacted by grazing than smaller species. Accordingly,
based on the best available information, grazing has not been
demonstrated to be a threat to the species.
Chemical Applications
Earthworms have been shown to be sensitive to some pesticides
(Edwards and Bohlen 1996, pp. 283-285), and the toxicity varies
depending on the type of pesticide used. Generally, carbamates (organic
compounds derived from carbamic acid and frequently used in
insecticides) are the most toxic (Edwards and Bohlen 1996, pp. 283-
285). In addition, although chemicals may not result in direct
toxicity, they may have indirect effects such as reduction in organic
matter, which is a food source for earthworms. Contaminant exposure and
toxicity depends on a wide range of chemical, physical, and biological
factors, and the rate of application. Specific knowledge of the fate
and transport of the chemical within the environment, physicochemical
attributes of the exposure media, and biological characteristics of the
organism are required to determine if a species may be impacted by
environmental contaminants. Although pesticide application is
widespread within the Palouse, information on GPE distribution,
biology, and life history is limited. There is significant uncertainty
with regard to determining the potential impact pesticides might
present to this species, and what application rate(s) would be required
for those impacts to rise to a level of being a threat to the species.
Exposure could also vary, depending on the GPE's life-history strategy.
Anecic species (which we believe the GPE to be based on the best
available scientific information) may have less exposure than other
forms. For example, the black-headed worm (Aporrectodea longa), an
anecic species, was determined to be less susceptible to pesticides
because of its ability to burrow deep into the soil. This species also
undergoes an obligatory diapause in the summer months, which may limit
pesticide exposure (Wheatley and Hardman 1968, as referenced in Edwards
and Bohlen 1996, p. 280; Gerard 1967, as referenced in Edwards and
Bohlen 1996, p. 280). It is unknown whether the GPE undergoes a
diapause. In addition, in a midwestern United States study on
agriculture and earthworms, Simonson et al. (2010, p. 147) found the
most commonly applied pesticides and increased crop diversity did not
have a significant effect on either the endogeic or anecic earthworm
groups.
From 1992 through 1995, pesticides were assessed as part of the
National Water-Quality Assessment (NAWQA) Program, and at least one
pesticide was detected within 97 percent of surface water samples
collected within the Palouse bioregion. No pesticides were found in
groundwater (the only source of drinking water in the area) at
concentrations that exceeded drinking water standards or guidelines
(Roberts and Wagner 1996, p. 15). Although some data are available for
pesticide presence in surface and groundwater, there is little
information on pesticide presence or concentrations in soils within
documented GPE habitat. Many currently used pesticides are water
soluble and are much less persistent in soils than the organochlorine
pesticides used in the past.
Approximately 700,000 pounds of commonly used pesticides are
applied in the Palouse bioregion annually (Roberts and Wagner 1996, p.
2), and agricultural interests in the Palouse region apply many
herbicides to control invasive and noxious plants (Hall et al. 1999, p.
12, Table 3.08; Kellogg et al. 2000, p. 2). Wagner et al. (1995, pp.
21-22) identified several pesticides used in an area within the Palouse
bioregion, several of which were detected in water samples, including
Triazine (Atrazine) (pp. 15-16, Table 4), although several comments
(e.g., McGregor in litt., p. 4) stated that Triazine family herbicides
are not used commercially for agriculture in the Palouse. The petition
claims no-till farming uses herbicides rather than tilling for weed
control, resulting in higher herbicide use in no-till fields than in
tilled fields (Veseth 1986a, p. 1; Petition, p. 12); however, no-till
farming was estimated in 1989 to be used on only 5 percent of the
fields in the Palouse region (Hall 1999, p. 15). Several individuals
from the Palouse bioregion commented that no-till farming uses
glyphosate herbicides (Jensen 2010, in litt., p. 5; McGregor 2010, in
litt., p. 2; Mick 2010, in litt., p. 2), which studies show have no
toxicity for earthworms when properly applied (Edwards and Bohlen 1996,
p. 304). Individuals also commented that agricultural users apply
fertilizers and pesticides sparingly and with precision because of the
costs involved (Barstow
[[Page 44558]]
2010 in litt., p. 2; Jensen 2010 in litt., p. 5).
There is limited information available on pesticide use outside of
the Palouse bioregion in the vicinity of documented GPE locations. One
study detected such chemicals in irrigation canal monitoring sites in
the Yakima watershed (Johnson 2007, p. 1). However, the monitoring
sites used for the Johnson (2007) study appear to be lower in the
watershed than the Ellensburg GPE location (Fender and McKey-Fender
1990, pp. 358, 366). Although groundwater and surface water pesticide
monitoring studies provide an indication of pesticide use in the
general area, the data are not informative on whether pesticides are
present in GPE-documented habitats. We are also unaware of any
pesticide monitoring studies in the vicinity of the GPE location near
Leavenworth, Washington.
In summary, agricultural lands have been the primary focus areas
for pesticide and herbicide monitoring studies; however, the GPE has
not been documented to date in these types of areas. Although we have
some information on pesticide applications in the Palouse area, and
some generalized information regarding pesticide toxicity to
earthworms, the available information is inadequate to determine how
and whether those pesticides impact soils or habitats occupied by the
GPE. We have some limited pesticide application information for the
Ellensburg, Washington, vicinity, although the data are not
particularly enlightening with regard to proximity to the GPE location,
and we have no pesticide information related to the GPE location
documented near Leavenworth, Washington. However, information on
another anecic species (Wheatley and Hardman 1968, as referenced in
Edwards and Bohlen 1996, p. 280; Gerard 1967, as referenced in Edwards
and Bohlen 1996, p. 280) indicates deep-burrowing anecic species are
less susceptible to pesticides. In addition, the prevailing information
indicates the GPE is an anecic species, and anecic species have less
exposure to pesticides than other earthworm life-history forms. We do
not have information on GPE pesticide exposure in areas outside of the
Palouse region, and the exposure will vary with the distribution,
habitat types, and pesticide uses in those areas. The GPE has a wider
range and occurs in more diverse habitats than previously known, and we
have little information on pesticide applications occurring in those
areas. Accordingly, the best available scientific information does not
indicate the application of pesticides or herbicides is a threat to the
GPE.
Urbanization and Rural Development
The petitioners claim that urban sprawl and rural development
negatively impact GPE habitat in the Palouse and Ellensburg areas. The
Ellensburg, Washington; Pullman, Washington; and Moscow, Idaho human
populations increased by approximately 76, 88, and 73 percent,
respectively since 1980 (Petition, p. 12; http://www.census.gov, figure
4). The petition states that urban development compacts soil, removes
topsoil, and favors nonnative, invasive earthworms (Petition, pp. 12-
13), and road construction affects remaining prairie remnants
(Petition, p. 13). If urban or rural development were to occur on
remnant prairie habitats in the Palouse, there may potentially be an
impact to the GPE. However, the Palouse prairie is not the only habitat
type used by the GPE, as the species has also been located in Douglas-
fir forest in the Palouse and in ponderosa pine forest near
Leavenworth, Washington (see Table 1 above).
The petitioners (Petition p. 13) expressed concern about a
potential rerouting of U.S. 95 through a large prairie remnant in the
Palouse bioregion south of Moscow, Idaho. The planning for this project
is ongoing (Idaho Department of Transportation (IDOT) 2011a, p. 1).
There were three action alternatives under consideration (IDOT 2011c,
p. 1), one of which (the eastern alternative) would impact Paradise
Ridge, an area where the GPE has been documented. However, the IDOT
forwarded only alternatives that would have no direct impact on rare
plant communities (including remnant prairie habitat) for further
analysis (IDOT 2011b, p. 21, 25), and as a result, the Paradise Ridge
GPE site will not be affected by the IDOT project. Urban and rural
development in prairie remnants is still possible, given that Latah
County, Idaho, and Whitman County, Washington, do not prohibit this
type of development (Latah County Board of Commissioners 2010; Whitman
County 2010); however, there are significant scientific uncertainties
regarding the full extent of habitat types used by the GPE, as well as
the species' distribution, range, and population trends. In summary,
the best available scientific information does not indicate that
urbanization and rural development are threats to the GPE.
Forest Management
The impact of forest management actions on soils varies, and
uneven-aged management (i.e., selective harvest) can result in
machinery-induced soil compaction over a larger area than even-aged
management (i.e., clearcut harvest) (Harvey et al. 1994, p. 44).
However, while selective timber harvest practices may result in soil
disturbance or compaction from heavy equipment, there will be less loss
of surface or soil organic matter than when clearcut timber harvest
methods are used (James 2000, p. 10). Forest management operations can
alter the cycling of above-ground organic materials and their
incorporation into soil (Harvey et al. 1994, p. 11), which may result
in not only impacts to soil nutrients, but also changes to soil
characteristics such as water-holding capacity, aeration, drainage, and
cation exchange.
The GPE has been documented in Douglas-fir forest at Moscow
Mountain in the Palouse, and recently confirmed in dry ponderosa pine
forest near Leavenworth, Washington (see Table 1 above), although
information regarding details on the forest stand at the GPE locations,
and the extent of habitats the GPE occupies in forested environments,
is incomplete. Forest types have changed in the Columbia Basin since
historical times, although the numbers of forested acres are not
substantially different (Quigley et al. 1996, p. 54). The potential
impacts to the GPE from forest management activities would likely
depend on whether the species requires certain forest types or ages,
and if so, the specific nature of the management prescription being
applied in those areas. There are uncertainties with regard to whether
the GPE is restricted to certain types of forests, certain ages of
forest, or certain elevations or other site characteristics, or whether
surface vegetation is relevant to the species. If the GPE occurs in
multiple types and ages of forest, the availability of a particular
forested habitat type may not be a limiting factor, and forest
management may have little impact.
James stated in 1995, that he can ``confidently state that nothing
is known of the impact of any management practice on any Columbia River
Basin native earthworm species'' (James 1995, p. 12). However, in 2000,
James stated that logging: (1) Degrades earthworm habitat, potentially
to the point of causing extirpation and changes in plant communities,
and (2) may degrade habitat through changing soil type, soil
temperature, moisture regime, or food resources (James 2000, p. 10). In
his 2000 study, James also related the primary effect of tree removal
on endogeic earthworms to soil climate and the availability of surface
and soil organic matter sufficient to support earthworms until second-
growth plants become established. James also stated
[[Page 44559]]
that epigeic species would be expected to suffer most from the loss of
tree cover because the preferred microhabitat would be less hospitable
and ultimately less abundant, with the loss of annual leaf input, and
indicated that disturbance caused from heavy equipment use may be the
most deleterious to earthworms (Shaefer and others 1990, in James 2000,
p. 10). However, James did not discuss how these types of activities
would affect an earthworm species with a deep-burrowing, anecic, life-
history strategy (James 2000, p. 10), such as the GPE. The Service
recognizes that forest management activities can affect soils,
temperatures, and vegetation, and the impacts would vary with types of
forest management, types of forest, and habitat needs of the GPE.
However, we were unable to determine how much forested habitat the GPE
occupies or where it occurs in forested habitat (other than the above
confirmed localities). Additional surveys will be needed to determine
the extent of forested habitat occupied by the species. In addition, we
have no information to indicate how GPE would respond to different
types of forest management activities. Therefore, the best available
information does not indicate that forest management activities
represent a threat to the GPE.
Summary of Factor A
The GPE is known to occur in both grassland habitats and forested
habitats in the Palouse. Native grassland habitats in the Palouse have
declined to very low levels; information on changes to forested
habitats in the Palouse is less well understood. The species' range
outside of the Palouse region is substantially greater than was
previously known, and includes portions of the eastern slope of the
Cascade Mountains. Survey efforts have been limited, it is difficult to
survey for the species, and effective survey methods remain to be
developed. In addition, there are significant scientific uncertainties
regarding the GPE's distribution, habitat diversity, biology, and
population trends, which need to be resolved to be able to conduct a
credible scientific assessment of potential threats to the species. The
best available information is inconclusive with regard to whether soil
pH is a limiting factor, or whether there are certain types of
management activities that affect soil pH in a manner that presents a
threat to the GPE. The literature suggests that compacting soils may
result in impacts to earthworms, depending on their life-history
strategy. However, there is no information with which to determine with
reasonable confidence whether soil compaction is occurring in GPE
habitat, and if so, whether it would result in a negative response in
the species.
While there may have been historical impacts to the GPE from
agricultural conversion in the Palouse, most agriculture conversion
activities were completed by 1910 (McGregor, 1982, p. 109). The extent
to which agricultural activities currently present a threat to the GPE
is undeterminable, given the limited information available on the
species' life history, its range, and the diversity of habitat types
where it occurs. However, the species has not been collected in
agricultural areas to date. The extent of the GPE's range and habitat
types used beyond the Palouse is also unknown. While there may
potentially be impacts from grazing activities, we have an incomplete
understanding of the species' occupied habitat, whether grazing occurs
therein, the magnitude and intensity of grazing activities in those
areas, and the GPE's exposure to grazing impacts. We have some
information on pesticides used in the Palouse area, and we have
generalized information on pesticide toxicity to earthworms. However,
we are unable to correlate that information to soils or habitats used
by the GPE in the Palouse or elsewhere, and whether the GPE is exposed
to those chemicals. The limited information on pesticide applications
in the Ellensburg, Washington, vicinity is not instructive with regard
to whether or not those activities might threaten the GPE, and there is
no information related to pesticide application in the Leavenworth,
Washington, GPE locality. Because of our limited knowledge of the
species' range and occupied habitat, we cannot credibly evaluate the
threat of urban or rural development to the species. We recognize that
forest management activities can affect soils, temperatures, and
vegetation, but there is no information correlating these activities to
a possible negative response by the GPE. In summary, there is very
little information available, and the best available scientific
information does not indicate the present or threatened destruction,
modification, or curtailment of the GPE's habitat or range from any of
the above activities constitutes a threat to the species such that
listing under the Act is warranted.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
The petition did not identify overutilization for commercial,
recreational, scientific, or educational purposes as a potential threat
to the GPE. Unlike butterflies, for example, earthworms are not likely
targets for collection by hobbyists. Recent records of the GPE are
based on the few individuals that were killed during or after their
collection (fewer than 10). While we anticipate some additional GPE
mortality due to scientific collection as we learn more about the
species, we have no reason to believe the loss of a few individuals for
scientific purposes would present a threat to the continued existence
of the species. Therefore, we conclude that overutilization for
commercial, recreational, scientific, or educational purposes is not a
threat to the species such that listing under the Act is warranted.
Factor C. Disease or Predation
The petition did not identify any threats to the GPE related to
disease or predation. Hendrix and Bohlen (2002, p. 802) stated that
imported nonnative earthworms may be vectors for plant or animal
pathogens or viruses, but the authors do not correlate this potential
threat to the GPE. Although James (1995, p. 11) stated that predation
on earthworms can be accentuated by tilling the soil and exposing
earthworms to bird predators, the correlation to the GPE is uncertain
as the GPE is believed to be an anecic species and therefore may be
less likely to be exposed by tilling. Also, surveys to date have not
found the GPE in agricultural fields, although we acknowledge the
extent of those surveys has been limited. However, the species would
not be exposed to increased predation caused by ongoing tillage if it
does not occupy agricultural areas. In summary, we do not have any
evidence indicating that disease or predation is a threat to the GPE
such that listing under the Act is warranted.
Factor D. The Inadequacy of Existing Regulatory Mechanisms
In our 2010 90-day finding (75 FR 42064; July 20, 2010), we
determined the existing regulatory mechanisms may be inadequate to
address potential threats to the GPE. The petitioners claim Federal,
State, or local regulations do not specifically protect the GPE or its
habitat. The Washington Department of Fish and Wildlife identifies the
GPE as a species of concern (WDFW 2009, p. 1), although this status
does not provide regulatory protection for the species. The petition
states the Palouse Subbasin Management Plan (Gilmore 2004) includes
objectives to protect and restore native grassland habitat within the
Palouse subbasin, and increase wildlife habitat value on agricultural
land, but is voluntary in nature and
[[Page 44560]]
does not provide regulatory mechanisms that protect the GPE or its
habitat. Habitat conversion in the Palouse may still occur, as neither
Latah County, Idaho, nor Whitman County, Washington, have ordinances or
regulations to prevent native habitat conversion (Latah County Board of
Commissioners 2010, pp. 1-27; Whitman County 2010, pp. 1-76). However,
we do not have evidence that habitat loss is a threat (see Factor A
discussion). The petition also acknowledges the existence of the U.S.
Forest Service, Bureau of Land Management, U.S. Fish and Wildlife
Service, Environmental Protection Agency, and National Oceanic and
Atmospheric Administration (NOAA) Fisheries Memorandum of Understanding
(MOU, USDA Forest Service et al. 2003), in which the agencies agreed to
voluntarily utilize the scientific findings of the Interior Columbia
Basin Strategy (CBS) to guide project implementation and to revise
resource management plans. The petitioners state the MOU and CBS do not
address the GPE or provide regulatory mechanisms for its protection
(Petition, p. 15), and claim existing regulations are ineffective in
reducing the importation of nonnative earthworm species, which present
a threat to the GPE. However, the best available information does not
indicate that exotic earthworms represent a threat to the GPE (see
Factor E discussion).
The U.S. Environmental Protection Agency (EPA) Office of Pesticide
Programs evaluates which ingredients and which pesticide products can
be used (registered) in the United States. The EPA evaluates the
potential effects of pesticides on human health and the environment,
conducts risk assessments, and works with companies to develop label
instructions that ensure safety (see the National Pesticide Information
Center at http://www.npic.orst.edu/reg.htm). One study found the use of
pesticides at recommended rates had no detectable negative effects on
earthworms in anecic or endogeic species (Simonsen et al., 2010, cited
in Johnson-Maynard, 2010, in litt., p. 2). Therefore, the best
available information indicates that the species is not threatened by
the inadequacy of pesticide management.
Surveys for the GPE have been limited, and there are significant
uncertainties regarding the species' distribution and life history, as
well as the diversity of habitat types where it may be found. This type
of information is essential to credibly assess whether or not existing
regulatory mechanisms are adequate to address potential threats to the
species. While we acknowledge the regulations and plans described above
do not provide specific protections for the GPE, we have no information
to indicate this lack of specific protections is resulting in threats
to the species. Therefore, we find that the available information does
not support a conclusion that the inadequacy of existing regulatory
mechanisms is a threat to the GPE.
Factor E. Other Natural or Manmade Factors Affecting the Species'
Continued Existence
The petitioners claim that the GPE is threatened by invasive,
nonnative earthworms (Petition, p. 1). In a 3-year study of earthworms
in the Palouse region of eastern Washington and Idaho, S[aacute]nchez-
de Le[oacute]n and Johnson-Maynard (2009, p. 1393) found a dominance of
invasive, nonnative earthworms in both native and nonnative grasslands.
Nonnative earthworms can invade new habitats, change the ecological
soil functions, and displace native species (Hendrix and Bohlen 2002,
p. 805; Petition, p. 16). Earthworm populations are dominated by
nonnative earthworms in agricultural sites and native prairie remnants
in the Palouse region (Fauci and Bezdicek 2002, p. 257; S[aacute]nchez-
de Le[oacute]n and Johnson-Maynard 2009, pp. 1396, 1399-1400; Petition,
p. 16). Habitat conversion favors invasion of nonnative earthworm
species that are better adapted to a disturbed or degraded environment
(Petition, p. 16; James 1995, p. 5). James (1995, p. 5) stated that
many exotic species occur in the Columbia Basin, possibly altering
previously worm-free soils and nutrient cycling pathways, competing
with native species, and generally modifying any processes linked to
soil physical or chemical properties. He also stated that invasive
earthworm species present a potential threat to the GPE, and described
the loss of a deep-dwelling Illinois earthworm species as an example of
this threat, although the particular study was not cited (James 2009,
in litt., p. 2). Based on the limited information that was provided, we
were unable to locate the study. James stated that although invasive
earthworms do not always reduce or eliminate populations of indigenous
worms, the invasion cannot help, and some species may be highly
competitive with, a deeper-dwelling species like the GPE, while others
may not (James 2009, in litt., p. 2). There are substantial weaknesses
in extrapolating data from an Illinois earthworm species to the GPE,
because we have no information that would indicate the responses would
be similar. While the Service concludes that the GPE is anecic based on
the best available information, there is some expert disagreement on
the GPE's life-history strategy. However, it is unclear whether this
matters in relation to invasion by nonnative earthworms, and James
(2009 in litt. p. 2) did not present a scientific basis for using an
Illinois species as a surrogate for the GPE.
We agree that a correlation of decline and extirpation of some
native earthworm species with the arrival of introduced earthworm
species is well documented (Hendrix and Bohlen 2002, pp. 805-806;
S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009, pp. 1393-1394),
although the cause may not always be direct. The causes of the declines
of native species of earthworms are not documented, but theories center
on ecosystem disturbance (Hendrix and Bohlen 2002, pp. 805-806) and
competitive exclusion (James 2000, p. 8; Hendrix and Bohlen 2002, pp.
805-806). In addition, James (2009, in litt., p. 2) noted that invasive
earthworms do not always reduce or eliminate populations of indigenous
earthworms. Depending on ecological requirements, some species may be
highly competitive with a deeper-dwelling species like the GPE, and
some not competitive, or there may be a combination of effects coupled
with habitat modification. Co-occurrence of native and nonnative
earthworm species is common both in disturbed and undisturbed
ecosystems; however, it is not known if this is a transient or
permanent state (Hendrix 2006, p. 1203). Ecosystem disturbance
sufficient to degrade or destroy habitat for native species may be
caused by the arrival of introduced worm species, or the arrival of
introduced species may follow habitat degradation caused by other
factors (Hendrix and Bohlen 2002, pp. 805-806). Nonnative earthworm
invasions may depend on the degree of disturbance, competition with
natives, and adaptability to site conditions (Hendrix and Bohlen 2002,
p. 1203; S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009, p.
1394).
In a 2003-2005 research effort in the Palouse region of
southeastern Washington and northern Idaho, S[aacute]nchez-de
Le[oacute]n and Johnson-Maynard (2009, pp. 1394-1395) compared four
paired study sites representing native prairie remnants and CRP set-
aside lands. The study objective was to characterize and compare native
and nonnative earthworm populations in two important grassland
ecosystems within the Palouse region. Their results found that one
invasive earthworm species, the southern worm (Aporrectodea
trapezoides) comprised
[[Page 44561]]
90 percent of the total earthworm density in their study areas
(S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009, p. 1396). One
GPE was collected at one of the four prairie remnant study sites. The
authors suggested that because native earthworms are found in
fragmented native habitats along with exotic earthworms, the GPE may be
able to coexist with exotic species in Palouse prairie remnants. They
indicated that further study would be required to determine whether the
GPE is a resilient species based on its deep-burrowing behavior, or
whether the results of their study demonstrate a species replacement
process (S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009, pp.
1398).
The rarity of native earthworms in their native prairie remnant
study areas lends support to the researchers' theory that native
earthworms are being replaced by nonnative earthworms, even in visibly
intact remnants of fragmented habitats (S[aacute]nchez-de Le[oacute]n
and Johnson-Maynard 2009, pp. 1398-1399). The researchers suggested
Apporectodea trapezoides may compete with the GPE for food in upper
layers of soil (S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009,
pp. 1398-1399), but could not exclude the possibility that the GPE did
not historically occur in high densities within these prairie remnants
because of their steep slope or high rock content, the very factors
that prevented these areas from being plowed and preserved them as
remnant prairie (S[aacute]nchez-de Le[oacute]n and Johnson-Maynard
2009, p. 1398). They acknowledged that these findings are inconsistent
with other studies showing that native earthworms predominate in
undisturbed or minimally disturbed grasslands (James 1991, pp. 2101-
2109; Callaham et al. 2003, pp. 1079-1093; Winsome et al. 2006, pp. 38-
53; in S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009, pp.
1397-1398).
The researchers suggested that a combination of extensive habitat
fragmentation in the Palouse region, low habitat quality of remaining
prairie remnants, and possible competitive interactions with nonnative
earthworms could have decimated GPE populations at their study sites
(S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009, p. 1398). They
acknowledged that no information is available on GPE pre-agricultural
density or distribution, but the description of the species as being
abundant by Smith (1897) contrasts with the rarity of finding the
earthworm today. They stated that this suggests a significant reduction
in population size (S[aacute]nchez-de Le[oacute]n and Johnson-Maynard
2009, pp. 1394, 1399), but acknowledge their sampling methodology could
have influenced the results. The hand-sorting sampling method is
regarded as the best method to estimate abundance of most earthworm
species, but is also known to underestimate the abundance of deep-
burrowing species. The researchers recommend the use of a combination
of methods for future studies, including non-destructive alternatives
such as electrical methods or extraction methods with chemicals of low
toxicity that are more suited for deep-burrowing earthworm species
(S[aacute]nchez-de Le[oacute]n and Johnson-Maynard 2009, p. 1399).
The GPE's range is more extensive than previously known, survey
efforts for this species have been limited, and effective survey
protocols remain to be developed. We acknowledge conflicting opinions
by earthworm researchers regarding the GPE's life-history strategy,
which could influence how it interacts with exotic earthworms. However,
we believe the prevailing evidence points to the GPE being a deep-
burrowing anecic species, based on observations in the field by
scientists who appear to be most familiar with this particular species,
and the report by Smith (1897, pp. 202-203) describing burrows
extending to a depth of over 15 feet in new road cuts. Endogeic worms
(which the petitioners believe the GPE to be) live in the upper layers
of mineral soil, whereas anecic earthworms live in deep, semi-permanent
burrows. The researchers S[aacute]nchez-de Le[oacute]n and Johnson-
Maynard also acknowledge that the hand-sorting sampling method (which
has apparently been applied in most earthworm surveys) underestimates
the abundance of deep-burrowing species. In addition, the limited
evidence available does not lead to a reasoned scientific conclusion
regarding competitive interactions between exotic earthworms and the
GPE. In summary, we do not have evidence to support a conclusion that
competition with exotic earthworms is a threat to the GPE.
Nonnative Plants
The petitioners describe the existence of introduced annual grasses
and noxious weeds in the Palouse region, including Poa pratensis
(Kentucky bluegrass), crops, Bromus tectorum (cheatgrass), and
Centaurea solstitialis (yellowstar-thistle) (Gilmore 2004, pp. 1-87),
and state that it is likely these species do not provide the same
quality and quantity of earthworm forage as native vegetation
(Petition, p. 17). However, they did not provide any evidence to
support this statement. There may be differences in nutritive value
between weeds and native plants, and there may be differences in
phenology (e.g., nonnative plants emerging at a different time than
native plants), but it is unknown if this is important to the GPE.
Invasive weed control in the Palouse is difficult (Jensen, 2010, in
litt., p. 3; Nyamai 2009, pp. 6-7, 21-22). Native plant communities in
the Palouse are susceptible to invasion by nonnative plants (Gilmore
2004, pp. 1-26; James 2000, p. 8); domination of deep-soil sites by
Kentucky bluegrass is common, and in shallow soils cheatgrass and
yellowstar-thistle weeds compete with native grasslands. McGregor
(1982, pp. 124-125) commented that nonnative weeds, including
cheatgrass, have been present in the Palouse region since the 1890s.
The Draft Palouse Subbasin Management Plan (Gilmore 2004, pp. 1-86)
states that exotic weed invasions are possibly the greatest threat
facing the grasslands and shrublands of the arid and semiarid West
today, and species-rich ecosystems are being converted to monotonous
weedlands as aggressive weeds replace native plants and degrade habitat
for wildlife.
There are significant scientific uncertainties regarding the
distribution and life history of the GPE, and the range of habitat
types it occupies is unknown. Although there have been some studies
relevant to nonnative plant invasion and conversion of native habitats
and ecosystems, we are unaware of any scientific studies or other data
that would allow an extrapolation of these observations to the GPE.
Accordingly, we have no information to indicate that the introduction
of nonnative plants represents a threat to the species.
Climate Change
The petitioners noted that, because Fender and McKey-Fender (1990,
p. 366) describe annual precipitation as a parameter of GPE habitat, it
is likely that changing weather patterns caused by global warming will
impact this species' habitat and distribution (Petition, p. 17). This
citation in fact defines the lower limit of precipitation tolerated by
argilophilini worm species to be about 15 in (38 cm) annually, which
the authors characterize as being ``about the edge of moist forests in
our area, although the range of Driloleirus americanus extends into
treeless areas.'' Although the petition expresses a concern about
future climate change and its effects on the GPE, it did not present
information or data in this regard.
The Service evaluated information available in our files and
queried other available information related to this potential threat.
Lawler and Mathias
[[Page 44562]]
(2007, pp. 19-20) investigated possible climate change impacts to
vascular plants, stating that plants may mature earlier, creating
potential mismatches between pollinators and plants, parasites and
hosts, and herbivores and food sources; increased summer temperatures
and decreased summer precipitation may lead to changes in distribution
of some plant species; sagebrush steppe and grasslands may contract,
while dry forests and woodlands expand; and plant distribution changes
will depend in part on plant water-use efficiencies. According to the
United Nations Framework Convention on Climate Change (2010, p. 1),
plant growth may benefit from fewer freezes and chills, but some crops
may be damaged by higher temperatures, particularly if combined with
water shortages. Certain weeds may expand their range into higher-
latitude habitats. Higher levels of carbon dioxide should stimulate
photosynthesis in certain plants, in principle. This is particularly
true for C3 plants (named for their carbon fixation pathway) because
increased carbon dioxide tends to suppress their photo-respiration. C3
plants make up the majority of species globally, especially in cooler
and wetter habitats, and include most crop species, such as wheat,
rice, barley, cassava, and potato.
It is difficult to predict how or if future changes in growth or
distribution of vegetation resulting from climate change will affect
local conditions for weeds, native vegetation, or both, or to predict
how such changes would affect earthworms. Earthworm mortality can
result from extreme temperatures, and the upper lethal temperature for
different earthworm species is lower than for other invertebrates
((Edwards and Bohlen 1996, p. 146) (e.g., 28 [deg]C (82 [deg]F) for
Lumbricus terrestris; 37 to 37.75 [deg]C (98.6 to 100 [deg]F) for
Pheretima californica (Schread 1952, as referenced in Edwards and Lofty
1977, pp. 156-157)). Earthworms tolerate higher temperatures by
migrating, or burrowing deeper, but must still be able to feed on the
surface or the top layers of the soil.
The petition did not present any specific information, and we are
unaware of any studies, that would facilitate an evaluation of the
extent to which the GPE may be affected by: (1) Increased air
temperatures or soil changes; (2) earlier seasonality of plant
production; or (3) changes in plant distribution. Climate change models
used in the Intergovernmental Panel on Climate Change Fourth Assessment
Report project increased air annual temperatures in the Pacific
Northwest of, on average, 1.1 [deg]C (2.0 [deg]F) by the 2020s, 1.8
[deg]C (3.2 [deg]F) by the 2040s, and 2.9 [deg]C (5.3 [deg]F) by the
2080s, compared to 1970 and 1999 (averaged across all climate models);
however, increased air temperature does not necessarily correlate with
increased surface or soil temperatures. Projected changes in annual
precipitation averaged over all models are small (+1 to +2 percent),
but some models project an enhanced seasonal precipitation cycle with
changes toward wetter autumns and winters, and drier summers (Littell
et al., 2009, p. 1). In the Pullman, Washington, area, baseline annual
precipitation is estimated at 21.1 in (53.6 cm); models projecting to
2080 do not project annual precipitation below 15 in (38.1 cm) under
any scenarios (Climate Impacts Group 2009, pp. 197-198). Fifteen inches
(38.1 cm) of annual precipitation has been suggested as the lower limit
of precipitation tolerated by argilophilini worm species, such as the
GPE (Fender and McKey-Fender 1990, p. 366).
The impact of climate change on selected but economically
significant crops in eastern Washington was predicted to be generally
mild in the short term (i.e., the next two decades), but increasingly
detrimental with time (potential yield losses reaching 25 percent for
some crops by the end of the century). The projected elevated carbon
dioxide (CO2) was expected to provide significant mitigation
of climate change and its effects, and in fact result in important
yield gains for some crops (Littell et al. 2009, p. 212), and it is
likely that some native or nonnative plants would be similarly
increased, potentially increasing the forage base for GPE.
Existing climate change projections are inadequate to allow a
prediction regarding whether or how future climate change will impact
the GPE or its habitat. This is further complicated by the significant
uncertainties that exist regarding the species' distribution, biology,
and habitat needs. However, given that the prevailing evidence
indicates the species is anecic based on the results of survey efforts
and the description of deep burrows associated with the species (Smith
1897, pp. 202-203), it is reasonable to conclude the species' deep-
burrowing behavior will limit its exposure and increase its
adaptability to increased soil temperatures. It is unclear how or
whether drier summers would impact the GPE, or whether vegetation
changes would impact the GPE. Therefore, based on the best available
information, we conclude that climate change does not constitute a
threat to the species.
Summary of Factor E
Although the decline and extirpation of some native earthworm
species with the arrival of introduced earthworm species has been well
documented, survey efforts for this species have been limited and
effective survey protocols remain to be developed. In addition, there
are conflicting opinions by earthworm researchers regarding the GPE's
life history strategy, which could influence how it interacts with
exotic earthworm species. Native plant communities in the Palouse
bioregion are susceptible to invasion by nonnative plants, although we
are unaware of any studies that correlate nonnative plant invasion and
conversion of GPE habitat. The petition stated that future climate
change could affect the GPE, although no supporting information or data
was presented. Our examination of this concern has determined that
existing climate change projections are inadequate to predict how
future climate change may impact the GPE, which is further complicated
because of the significant uncertainties regarding the species'
distribution, life history, and the range of habitat types it occupies.
In summary, there is no scientific evidence to support a conclusion
that the GPE is threatened by competitive interactions with exotic
earthworms, the conversion of habitat by nonnative plants, or future
climate change.
Summary of Factors
A summary of our conclusions for each of the five factors is found
in Table 2. More specific information for each threat considered under
the five factors is available in the Summary of Information Pertaining
to the Five Factors section above.
Table 2--Section 4(a)(1) Listing Factors Summary of Potential Threats
Considered
------------------------------------------------------------------------
------------------------------------------------------------------------
Factor A.......................... Habitat loss and fragmentation: The
current or historical population,
distribution, and range of the GPE
is unknown; the habitats used by
the GPE are more diverse than
suggested by petitioners; survey
efforts have been limited and
sampling protocols remain to be
developed to improve detection
capabilities; there is no evidence
with which to correlate current or
future habitat loss with GPE
abundance or status.
[[Page 44563]]
Soil characteristics: There is no
information with which to link soil
disturbance with GPE presence or
absence.
Soil compaction: There is no
evidence that compaction is
occurring in GPE habitat or that
compaction would trigger a negative
response.
Soil chemistry: Earthworm responses
to soil pH vary depending on the
species, location, and life history
strategy; there is insufficient
information with which to establish
cause-effect relationship that
might be limiting to GPE; and there
is no information that Palouse
region soils are acidic enough to
negatively affect earthworms.
Tillage and agriculture: There is no
information indicating the GPE is
exposed to these activities, and no
GPEs have been documented in
agricultural areas.
Grazing: There is no information
with which to correlate GPE
distribution and grazing areas; the
species' range is unknown and
surveys have been limited; grazing
can sometimes benefit earthworms;
and larger species like the GPE may
be less impacted than smaller
species.
Chemical applications: Chemicals are
applied in agricultural areas--the
GPE has not been documented in
agricultural areas; the available
information is inadequate to
determine how and whether
pesticides impact soils occupied by
the GPE; some studies indicate
anecic species are less susceptible
to pesticides; the GPE has wider
range and occurs in more diverse
habitats than previously known; and
there is limited information on
pesticide applications in known GPE
areas.
Urbanization and rural development:
There are significant uncertainties
regarding GPE distribution, range,
population trends and extent of
habitat types used; and there is no
evidence that correlates
urbanization and rural development
with threats to the GPE.
Forest management: Information is
insufficient to determine the
extent of forested habitat occupied
by the GPE or where it occurs in
forested habitat; and there is no
information available regarding how
the GPE would respond to differing
types of forest management
activities.
Factor B.......................... Mortality resulting from scientific
collections: Earthworms are not
targets for collection by
hobbyists; some mortality is
expected from scientific
collection, but we have no basis to
conclude that removal of a few
individuals for this purpose would
have population-level impacts.
Factor C.......................... Disease: We do not have any evidence
indicating disease is a threat to
the GPE.
Predation resulting from exposure
during tilling operations: GPEs
have not been observed in
agricultural areas; the GPE is
believed to be an anecic species,
which would be less likely to be
exposed by tilling, even if it were
to occupy agricultural areas.
Factor D.......................... Non-regulatory programs and
measures: Although the WDFW
considers the GPE to be a species
of concern and the USFS, FWS, NOAA,
BLM, EPA developed a MOU agreeing
to use scientific findings of the
CBS to guide management plans,
these are voluntary measures and
have no regulatory affect;
EPA pesticide regulations: The EPA
regulates use of pesticide in the
U.S.; one study found the use of
pesticides at recommended rates had
no detectable negative effects on
anecic or endogeic earthworms; and
having a better understanding of
GPE distribution, life history, and
diversity of habitat used is
essential to credibly assess
whether existing regulatory
mechanisms are inadequate.
Factor E.......................... Nonnative invasive earthworms: The
co-occurrence of native and
nonnative earthworms is common in
both disturbed and undisturbed
ecosystems, and the limited
evidence available does not lead to
a reasoned scientific conclusion
regarding competitive interactions
between the GPE and exotic
earthworms;
Nonnative plants: Significant
scientific uncertainties exist
regarding GPE distribution, life
history, and range; the best
available information does not
allow an extrapolation of nonnative
plant invasion to GPE threats.
Climate change: The best available
information is insufficient to
determine the extent to which the
GPE might be affected by increased
air temperatures or soil changes,
earlier seasonality of plant
production, or changes in plant
distribution; fifteen inches of
annual precipitation was suggested
as lower limit of precipitation
tolerated by species such as the
GPE, although models projecting out
to 2080 do not show annual
precipitation in the Pullman, WA
vicinity falling below 15 inches
under any scenarios; and
significant uncertainties regarding
the GPE's distribution, biology,
and habitat needs frustrate efforts
to draw parallels between climate
change and the species' response.
------------------------------------------------------------------------
A: Present or threatened destruction, modification, or curtailment of
habitat or range;
B: Overutilization for commercial, recreational, scientific, or
educational purposes;
C: Disease or predation;
D: Inadequacy of existing regulatory mechanisms;
E: Other natural or manmade factors.
------------------------------------------------------------------------
Finding
As required by the Act, we considered the five factors in assessing
whether the GPE is endangered or threatened throughout all or a
significant portion of its range. We examined the best scientific and
commercial information available regarding the past, present, and
future threats faced by the GPE. We reviewed the petition, information
available in our files, and other available published and unpublished
information, and we consulted with the most qualified GPE experts and
queried universities, State agencies, conservation districts, and other
entities. In considering what factors might constitute threats, we must
look beyond the mere exposure of the species to the factor to determine
whether the species responds to the factor in a way that causes actual
impacts to the species. If there is exposure to a factor, but no
response, or only a positive response, that factor is not a threat. If
there is exposure and the species responds negatively, the factor may
be a threat and we then attempt to determine how significant a threat
it is. If the threat is significant, it may drive or contribute 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. This does not necessarily require empirical proof of a threat. The
[[Page 44564]]
combination of exposure and some corroborating evidence of how the
species is likely impacted could suffice. The mere identification of
factors that could impact a species negatively is not sufficient to
compel a finding that listing is appropriate; we require evidence that
these factors are operative threats that act on the species to the
point that the species meets the definition of endangered or threatened
under the Act.
The analysis of threats (the five factors) to determine if the
status of GPE meets the definition of endangered or threatened was
particularly challenging, because the range of the species appears to
be greater than it was originally thought to be. In addition to the
Palouse area prairie, the species has been documented in dry forest
habitat on the east slope of the Cascades. Survey effort for this
species has been low, especially outside of the Palouse grasslands, and
appropriate survey methods remain to be developed. In addition, the
life history of the GPE is not completely understood. There is still
some scientific debate regarding whether the GPE is an anecic or
endogeic species, although the most recent field observations and
prevailing scientific evidence indicates it is a deep-burrowing anecic
species (Johnson-Maynard 2010, p. 2), which would result in a different
exposure to threats than if it were an endogeic species. There is no
scientific basis to conclude that any of the activities identified as
threats by the petitioners are, in fact, threats to the GPE.
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 the GPE 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 the GPE does not
meet the definition of an endangered or threatened species throughout
its range.
Distinct Vertebrate Population Segment and Significant Portion of the
Range Analysis
After assessing whether the species is endangered or threatened
throughout its range, we next consider whether a distinct vertebrate
population segment (DPS) or whether any significant portion of the GPE
range meets the definition of endangered or is likely to become
endangered in the foreseeable future (threatened), in accordance with
the Service's Policy Regarding the Recognition of Distinct Vertebrate
Population Segments under the Endangered Species Act (61 FR 4722,
February 7, 1996). Because the GPE is not a vertebrate species, the
Distinct Vertebrate Population Segment policy is not applicable to this
finding.
Significant Portion of the Range
Having determined that the GPE does not meet the definition of an
endangered or threatened species, we must next consider whether there
are any significant portions of the range where the GPE is in danger of
extinction or is likely to become endangered in the foreseeable future.
Because of significant uncertainties regarding the range of the GPE,
the limited survey efforts, and the paucity of information regarding
its life history, there is nothing to suggest that threats are
disproportionately acting on any portion of the species' range, such
that the species is at risk of extinction now or in the foreseeable
future. Therefore, we find that listing the GPE as an endangered or
threatened species is not warranted throughout all or a significant
portion of its range. The designation of critical habitat for this
species as requested by the petitioner is not appropriate, based on our
determination that the species does not warrant listing under the Act.
The Service continues to be interested in the status of this unique
species. We request that you submit any new information concerning the
status of, or threats to, the GPE to our Washington Fish and Wildlife
Office (see ADDRESSES) whenever it becomes available. New information
will help us monitor the GPE and encourage its conservation.
References Cited
A complete list of references cited is available on the Internet at
http://www.regulations.gov and upon request from the Washington Fish
and Wildlife Office (see ADDRESSES).
Author(s)
The primary authors of this notice are the staff members of the
Washington Fish and Wildlife 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: July 12, 2011.
David Cottingham,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2011-18645 Filed 7-25-11; 8:45 am]
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