[Federal Register Volume 81, Number 189 (Thursday, September 29, 2016)]
[Rules and Regulations]
[Pages 66842-66865]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-23546]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R4-ES-2015-0137; 4500030113]
RIN 1018-AZ95
Endangered and Threatened Wildlife and Plants; Endangered Species
Status for Chamaecrista lineata var. keyensis (Big Pine Partridge Pea),
Chamaesyce deltoidea ssp. serpyllum (Wedge Spurge), and Linum arenicola
(Sand Flax), and Threatened Species Status for Argythamnia blodgettii
(Blodgett's Silverbush)
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), determine
endangered species status under the Endangered Species Act of 1973
(Act), as amended, for Chamaecrista lineata var. keyensis (Big Pine
partridge pea), Chamaesyce deltoidea ssp. serpyllum (wedge spurge), and
Linum arenicola (sand flax), and threatened species status for
Argythamnia blodgettii (Blodgett's silverbush), all plant species from
south Florida. The rule adds these species to the Federal List of
Endangered and Threatened Plants.
DATES: This rule is effective October 31, 2016.
ADDRESSES: This final rule is available on the Internet at http://www.regulations.gov. Comments and materials we received, as well as
supporting documentation we used in preparing this rule, are available
for public inspection at http://www.regulations.gov. Comments,
materials, and documentation that we considered in this rulemaking will
be available by appointment, during normal business hours at: U.S. Fish
and Wildlife Service, South Florida Ecological Services Field Office,
1339 20th Street, Vero Beach, FL 32960; telephone 772-562-3909;
facsimile 772-562-4288.
FOR FURTHER INFORMATION CONTACT: Roxanna Hinzman, U.S. Fish and
Wildlife Service, South Florida Ecological Services Field Office, 1339
20th Street, Vero Beach, FL 32960; telephone 772-562-3909; facsimile
772-562-4288. Persons who use a telecommunications device for the deaf
(TDD) may call the Federal Information Relay Service (FIRS) at 800-877-
8339.
SUPPLEMENTARY INFORMATION:
Executive Summary
Why we need to publish a rule. Under the Endangered Species Act, a
species may warrant protection through listing if it is endangered or
threatened throughout all or a significant portion of its range.
Listing a species as an endangered or threatened species can only be
completed by issuing a rule.
The basis for our action. Under the Endangered Species Act, we may
determine that a species is an endangered or threatened species based
on any of 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. We have determined that the threats
to Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii consist
primarily of:
Habitat loss and modification through urban and
agricultural development, and lack of adequate fire management (Factor
A); and
The proliferation of nonnative, invasive plants;
stochastic events (hurricanes and storm surge); maintenance practices
used on roadsides and disturbed sites; and sea level rise (Factor E).
Existing regulatory mechanisms have not been adequate to reduce or
remove these threats (Factor D).
Peer review and public comment. We sought comments from independent
specialists to ensure that our determination is based on scientifically
sound data, assumptions, and analyses. We invited these peer reviewers
to comment on our listing proposal. We also considered all other
comments and information we received during the comment period.
Previous Federal Actions
Please refer to the proposed listing rule for Chamaecrista lineata
var. keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum arenicola,
and
[[Page 66843]]
Argythamnia blodgettii (80 FR 58536; September 29, 2015) for a detailed
description of previous Federal actions concerning these species.
Background
Please refer to the proposed listing rule (80 FR 58536; September
29, 2015) for the complete discussion of each plant's description,
habitat, taxonomy, distribution, population estimates, climate,
historical range, current range, status, and biology.
Below, we present only revisions to the discussions in the
Background section of the proposed listing rule based on new
information from peer review and public comments; as such, not every
plant, or every topic for a plant, will be discussed below.
Chamaecrista lineata var. keyensis (Big Pine partridge pea)
Species Description
Please refer to the ``Species Description'' section of the proposed
rule for the complete discussion. We make one minor editorial revision
to our description of the plant's fruit, as follows: The fruit is an
elongate pod, roughly similar to that of a pea, 33-45 millimeters (mm)
(1.3-1.8 inches (in)) long and 4.5-5.0 mm (0.19-0.17 in) wide, with a
soft fuzzy texture, which turns gray with age and eventually splits
open to release seeds (Irwin and Barneby 1982, p. 757; Small 1933, pp.
662-663).
Habitat
Please refer to the ``Habitat'' section of the proposed rule for
the complete discussion. In the Pine Rocklands discussion, we correct
the following names of species: Quercus elliottii (running oak) is
corrected to Quercus elliottii (running oak), and Psidium longipes
(longstalked stopper) is corrected to Psidium longipes (longstalked
stopper). We also correct the reference to hardwoods in the pine
rocklands of the lower Florida Keys; the hardwoods in the subcanopy
include species such as Byrsonima lucida and Mosiera longipes (Bradley
2006, p. 3).
Current Range, Population Estimates, and Status
Please refer to the ``Current Range, Population Estimates, and
Status'' section of the proposed rule for the complete discussion. We
make minor editorial revisions to the first sentence of the third
paragraph of that section, as follows: A second indicator, the
frequency with which Chamaecrista lineata var. keyensis occurred in
sample plots on Big Pine Key from data collected in 2005, 2007, and
2013, also shows a decline.
Linum arenicola (sand flax)
Habitat
Please refer to the ``Habitat'' section of the proposed rule for
the complete discussion. Under Roadsides and Other Disturbed Sites, we
make minor editorial corrections concerning the plant's persistence on
roadsides, as follows: Linum arenicola was at one time more common in
pine rocklands in Miami-Dade County, but a lack of periodic fires in
most pine rocklands fragments over the last century has pushed this
species into the more sunny, artificial environments it prefers
(Bradley and Gann 1999, p. 61).
Please refer to the ``Current Range, Population Estimates, and
Status'' section of the proposed rule for the complete discussion. We
make the following corrections to that discussion:
(1) We correct the description of the current distribution of Linum
arenicola in Miami-Dade County, as follows: In Miami-Dade County, the
current distribution of Linum arenicola is from just north of SW 184
Street (in the Martinez Pinelands Preserve), south to the intersection
of Card Sound Road and the C-102 canal, and west to SW 264 Street and
177 Avenue (Everglades Archery Range at Camp Owaissa Bauer).
(2) We correct our description of the compilation of all survey
work to include a missed citation for Possley (2016, pers. comm.). The
corrected sentence reads: Based on a compilation of all survey work
through 2016, including Austin (1980), Kernan and Bradley (1996, pp. 1-
30), Bradley and Gann (1999, pp. 61-65), Hodges and Bradley (2006, pp.
37-41), Bradley and Saha (2009, p. 10), Bradley (2009, p. 3), Hodges
(2010, pp. 4-5, 15), Bradley and van der Heiden (2013, pp. 6-12, 19),
Bradley et al. (2015, pp. 28-29), and Possley (2016, pers. comm.), of
26 historical population records for Linum arenicola, 12 populations
are extant and 14 are extirpated (see Table 3), a loss of roughly 54
percent of known populations, from the early 1900s to the present.
(3) Under Miami-Dade County, we correct the location of the seventh
population of Linum arenicola, as follows: A seventh small population,
located in 2014 at Zoo Miami, (Possley 2016, pers. comm.) is located on
county land.
(4) As a result of the corrections described in (1) through (3),
above, we present a revised version of the proposed rule's Table 3
(note: in the following table, USFWS stands for U.S. Fish and Wildlife
Service; FWC stands for Florida Fish and Wildlife Conservation
Commission; HARB stands for Homestead Air Reserve Base; and SOCSOUTH
stands for Special Operations Command South Headquarters):
Table 3--Summary of the Status and Trends of the Known Occurrences of Linum arenicola
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Most Recent
Population Ownership Population County Trend
Estimate
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Extant 12 records
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Big Pine Key................. USFWS, FWC, TNC 2,676 (2007) \1\ Monroe.......... declining.
\12\, Private.
Upper Sugarloaf Key.......... FDOT \13\, USFWS 73 (2010) \2\... Monroe.......... insufficient data.
Lower Sugarloaf Key.......... FDOT \13\, USFWS 531 (2010) \2\.. Monroe.......... stable.
Big Torch Key................ FDOT \13\, 1 (2010) \2\.... Monroe.......... declining.
Private.
Zoo Miami.................... Miami-Dade 56 (2014) \5\... Miami-Dade...... insufficient data.
County.
Martinez Pineland............ Miami-Dade 100-200 (2013) Miami-Dade...... insufficient data.
County. \6\.
Everglades Archery Range..... Miami-Dade 23 (2012) \7\... Miami-Dade...... insufficient data.
County.
HAFB \15\ 1--S of Naizare DOD \14\, Miami- 24,000 (2013) Miami-Dade...... stable.
BLVD. Dade County. \7\.
SOCSOUTH (HAFB 2--NW side of DOD \14\ (leased 74,000 (2009) 7 Miami-Dade...... stable.
Bikini BLVD). from Miami-Dade 10.
County).
HARB (SW 288 St. and 132 Ave) DOD \14\........ 37 (2011) \7\... Miami-Dade...... insufficient data.
C-102 Canal SW 248 St. to SFWMD \11\...... 1,000-10,000 Miami-Dade...... insufficient data.
U.S. 1. (2013) \7\.
[[Page 66844]]
L-31E canal, from SW 328 St. SFWMD \11\...... Plants occur Miami-Dade...... insufficient data.
to Card Sound Road. along 14 km
(8.7 mi) of
levee (2013)
\7\.
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Extirpated 14 records
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Middle Torch Key............. FWC, FDOT\13\... 3 (2005) \3\.... Monroe. ...........................
Ramrod Key................... FDOT\13\........ 110 (1979) \4\.. Monroe. ...........................
Park Key..................... FDOT\13\........ unknown (1961) Monroe. ...........................
\3\.
Boca Chica................... DOD\14\, other unknown (1912) Monroe. ...........................
(unknown). \3\.
Camp Jackson................. unknown......... unknown (1907) Miami-Dade. ...........................
\9\.
Big Hammock Prairie.......... unknown......... unknown (1911) Miami-Dade. ...........................
\9\.
Camp Owaissa Bauer........... Miami-Dade 10 (1983) \7\... Miami-Dade. ...........................
County.
Allapatah Drive and Old Private......... 256 (1996) \8\.. Miami-Dade. ...........................
Cutler Road.
Bauer Drive (Country Ridge Miami-Dade 8 (1996) \8\.... Miami-Dade. ...........................
Estates). County.
Silver Green Cemetery........ Private......... 47 (1996) \8\... Miami-Dade. ...........................
Palmetto Bay Village Center.. Private......... 12 (1996) \8\... Miami-Dade. ...........................
HAFB (Community Partnership DOD\14\, Miami- unknown (2010) Miami-Dade. ...........................
Drive). Dade County. \7\.
Coco Plum Circle (corner of Private......... 75 (1996) \8\... Miami-Dade. ...........................
Robles Street & Vista Mar
Street).
George Avery Pineland Private......... ``small colony'' Miami-Dade. ...........................
Preserve. (2002) \7\.
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\1\ Bradley and Saha 2009, p. 10.
\2\ Hodges 2010, p. 10.
\3\ Hodges and Bradley 2006, pp. 39-48.
\4\ Austin et al. 1980 in FNAI.
\5\ Possley 2016, pers. comm., p. 11.
\6\ Possley 2014, pers. comm.
\7\ Bradley and Van Der Heiden 2013, pp. 6-11.
\8\ Kernan and Bradley 1996, p. 9.
\9\ Bradley and Gann 1999, p. 65.
\10\ Bradley 2009, p. 3.
\11\ South Florida Water Management District (SFWMD).
\12\ The Nature Conservancy (TNC).
\13\ Florida Department of Transportation (FDOT).
\14\ Department of Defense (DOD).
\15\ Homestead Air Force Base (HAFB; decommissioned).
Biology
Please refer to the ``Biology'' section of the proposed rule for
the complete discussion.
We revise the Life History and Reproduction discussion to read:
Life History and Reproduction: Little is known about the life
history of Linum arenicola, including pollination biology, seed
production, or dispersal. Reproduction is sexual, with new plants
generated from seeds. L. arenicola is apparently self-compatible
(Harris 2016, pers. comm.). The species produces flowers nearly year
round, with maximum flowering from April to September, with a peak
around March and April. L. arenicola population demographics or
longevity have not been studied (Bradley and Gann, 1999, p. 65; Hodges
and Bradley 2006, p. 41; Hodges 2007, p. 2; Harris 2016, pers. comm.).
Argythamnia blodgettii (Blodgett's silverbush)
Species Description
Please refer to the ``Species Description'' section of the proposed
rule for the complete discussion. We clarify the description of the
leaves of Argythamnia blodgettii, as follows: The leaves, arranged
alternately along the stems, are 1.5 to 4.0 centimeters (cm) (0.6 to
1.6 in) long, have smooth (or rarely toothed) edges, are oval or
elliptic in shape, and often are colored a distinctive, metallic bluish
green when dried.
Taxonomy
Please refer to the ``Taxonomy'' section of the proposed rule for
the complete discussion.
To the end of the first paragraph, we add the following: Ingram
(1952) indicates the distribution of Argythamnia argothamnoides
(including Florida material) as Florida and Venezuela. As such, the
Service accepts the treatment of Argythamnia blodgettii as a distinct
species and therefore does not find a compelling justification to
remove the species from consideration for listing under the Act.
Current Range, Population Estimates, and Status
Please refer to the ``Current Range, Population Estimates, and
Status'' section of the proposed rule for the complete discussion. We
make the following corrections to that discussion:
(1) We correct the data in Table 4, presented below. (Note: In the
following table, USFWS stands for U.S. Fish and Wildlife Service; FWC
stands for Florida Fish and Wildlife Conservation Commission; DOD
stands for Department of Defense; and ENP stands for Everglades
National Park.)
(2) Because of the corrections presented below for Table 4, the
text preceding the table in the proposed rule is now incorrect. Based
on the data presented below in Table 4, there are 50 records for
Argythamnia blodgettii in Miami-Dade and Monroe Counties. Twenty
populations are extant, 15 are extirpated, and the status of 15 is
uncertain because they have not been surveyed in 15 years or more.
[[Page 66845]]
Table 4--Summary of the Status and Trends of the Known Occurrences of Argythamnia blodgettii
----------------------------------------------------------------------------------------------------------------
Most recent
Population Ownership population County Trend
estimate
----------------------------------------------------------------------------------------------------------------
Extant 20 records
----------------------------------------------------------------------------------------------------------------
Plantation Key, Snake Creek FWC............. 101-1,000 (2005) Monroe.......... Insufficient data.
Hammock. \2\.
Lower Matecumbe Key--Klopp FDEP \6\........ 11-100 (2000) Monroe.......... Insufficient data.
Tract. \2\.
Lignumvitae Key.............. FDEP \6\........ 101-1,000 (2005) Monroe.......... Insufficient data.
\2\.
Big Munson Island............ Private (Boy 1,001-10,000 Monroe.......... Insufficient data.
Scouts of (2005) \2\.
America).
North Key Largo.............. DOD, FDOT....... No estimate Monroe.......... Insufficient data.
(2005) \8\.
Key Largo--Dove Creek Hammock FWC, FDOT....... 11-100 (2005) Monroe.......... Insufficient data.
\2\.
Vaca Key (Marathon)--Blue FWC, FDOT....... 11-100 (2005) Monroe.......... Insufficient data.
Heron Hammock. \2\.
Windley Key--State Park...... FDEP \6\........ 11-100 (2005) Monroe.......... Insufficient data.
\2\.
Boca Chica KWNAS \7\ Runway DOD............. 1,001-10,000 Monroe.......... Insufficient data.
25. (2004) \2\.
Boca Chica Key KWNAS \7\ DOD............. 200 (2004) \2\.. Monroe.......... Insufficient data.
Weapons Hammock.
Big Pine Key................. USFWS, FWC, ~2,200 (2005) Monroe.......... Insufficient data.
private. \2\.
ENP Long Pine Key Deer NPS \5\......... 2,000 (2015) \4\ Miami-Dade...... Insufficient data.
Hammock area (Pine Block A),
Turkey Hammock area (Pine
Block B), Pine Block E.
Fuch's Hammock............... Miami-Dade 12 (2008) \ 1\.. Miami-Dade...... Insufficient data.
County.
Owaissa Bauer Addition....... Miami Dade Parks 377 (2014) \9\.. Miami-Dade...... Insufficient data.
and Recreation.
Camp Owaissa Bauer........... Miami Dade Parks 878 (2009) \9\.. Miami-Dade...... Insufficient data.
and Recreation.
Ned Glenn Pineland Preserve.. Miami Dade Parks 8 (2016) \10\... Miami-Dade...... Insufficient data.
and Recreation.
Camp Choee................... Private (Girl 3 (2005) \3\.... Miami-Dade...... Insufficient data.
Scout Council
of Tropical
Florida).
Florida Power and Light Private......... 7 (2015) \9\.... Miami-Dade...... Insufficient data.
Easement adjacent to Ludlam
Preserve.
Larry and Penny Thompson Park Miami Dade Parks 5,700 (2009) \9\ Miami-Dade...... Insufficient data.
and Recreation.
Boystown Pineland............ Private......... No estimate Miami-Dade...... Insufficient data.
(2005) \3\.
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Uncertain 15 records
----------------------------------------------------------------------------------------------------------------
Crawl Key, Forestiera Hammock Private......... 10 (1982) \3\... Monroe.......... Insufficient data.
Long Key State Park.......... FDEP............ No estimate Monroe.......... Insufficient data.
(1999) \2\.
Stock Island................. Private......... No estimate Monroe.......... Insufficient data.
(1981) \2\.
Boot Key..................... Private......... 11-100 (1998) Monroe.......... Insufficient data.
\2\.
Deering Estate............... State of Florida 11-100 (1991) Miami-Dade...... Insufficient data.
\1\.
Castellow Hammock............ Miami Dade Parks 11-100 (1991) Miami-Dade...... Insufficient data.
and Recreation. \1\.
Pine Ridge Sanctuary......... Private......... 2-10 (1992) \1\. Miami-Dade...... Insufficient data.
County Ridge Estates......... Private......... 11-100 (1999) Miami-Dade...... Insufficient data.
\1\.
Epmore Drive pineland........ Private......... 2-10 (1999) \1\. Miami-Dade...... Insufficient data.
Gifford Arboretum Pineland... Private......... 2-10 (1999) \1\. Miami-Dade...... Insufficient data.
Ned Glenn Nature Preserve.... Miami Dade Parks 11-100 (1999) Miami-Dade...... Insufficient data.
and Recreation. \1\.
Natural Forest Community #317 Private......... 2-10 (1999) \1\. Miami-Dade...... Insufficient data.
Old Dixie pineland........... Private......... 11-100 (1999) Miami-Dade...... Insufficient data.
\1\.
Castellow #33................ Private......... 12 (1995) \ 3\.. Miami-Dade...... Insufficient data.
Castellow #31................ Private......... 30 -50 (1995) Miami-Dade...... Insufficient data.
\3\.
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Extirpated 15 records
----------------------------------------------------------------------------------------------------------------
Upper Matecumbe Key.......... unknown......... No estimate Monroe. ...........................
(1967) \ 3\.
Totten Key................... NPS............. No estimate Monroe. ...........................
(1904) \1\.
Key West..................... City of Key West No estimate Monroe. ...........................
(1965) \1\.
SW 184th St. and 83rd Ave.... Private......... 0 (2016) \10\... Miami-Dade...... Insufficient data.
Tropical Park Pineland....... Miami Dade Parks 0 (2016) \9\.... Miami-Dade. ...........................
and Recreation.
Crandon Park--Key Biscayne... Miami Dade Parks 0 (2008) \9\.... Miami-Dade. ...........................
and Recreation.
Brickell Hammock............. unknown......... Extirpated 1937 Miami-Dade. ...........................
\1\.
Carribean Park............... Miami-Dade Extirpated 1998 Miami-Dade. ...........................
County. \1\.
Coconut Grove................ Miami-Dade Extirpated 1901 Miami-Dade. ...........................
County. \1\.
Coral Gables area............ unknown......... Extirpated 1967 Miami-Dade. ...........................
\1\.
Miller and 72nd Ave.......... unknown......... Extirpated 1975 Miami-Dade. ...........................
\1\.
[[Page 66846]]
Orchid Jungle................ Miami-Dade Extirpated 1930 Miami-Dade. ...........................
County. \1\.
Palms Woodlawn Cemetery...... Private......... Extirpated 1992 Miami-Dade. ...........................
\1\.
South of Miami River......... unknown......... Extirpated 1913 Miami-Dade. ...........................
\1\.
Naranja...................... Private......... No estimate Miami-Dade. ...........................
(1974) \3\.
----------------------------------------------------------------------------------------------------------------
\1\ Bradley and Gann 1999, p. 6.
\2\ Hodges and Bradley 2006, pp. 10-17.
\3\ FNAI 2011b.
\4\ Sadle 2015, pers. comm., p. 1.
\5\ National Park Service (NPS).
\6\ Florida Department of Environmental Protection (FDEP).
\7\ Key West Naval Air Station (KWNAS).
\8\ Henize and Hipes 2005, p. 25.
\9\ Possley 2016, pers. comm.
\10\ Lange 2016, pers. comm.
Summary of Comments and Recommendations
In the proposed rule published on September 29, 2015 (80 FR 58536),
we requested that all interested parties submit written comments on the
proposal by November 30, 2015. We also contacted appropriate Federal
and State agencies, scientific experts and organizations, and other
interested parties and invited them to comment on the proposal.
Newspaper notices inviting general public comment were published in the
Miami Herald and Key West Citizen. We did not receive any requests for
a public hearing. All substantive information provided during the
comment period has either been incorporated directly into this final
determination or is addressed below.
Peer Reviewer Comments
In accordance with our peer review policy published on July 1, 1994
(59 FR 34270), we solicited expert opinion from three knowledgeable
individuals with scientific expertise that included familiarity with
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii and their
habitats, biological needs, and threats. We received responses from all
three peer reviewers.
We reviewed all comments received from the peer reviewers for
substantive issues and new information regarding the listing of
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii. The peer
reviewers generally concurred with our methods and conclusions, and
provided additional information, clarifications, and suggestions to
improve this final rule.
(1) Comment: One peer reviewer and one public commenter provided
new information about the status of various populations of Linum
arenicola and Argythamnia blodgettii within Miami-Dade County
preserves. The peer reviewer suggested that the Service may be
overestimating the number of extant populations of A. blodgettii,
referring to outdated data for Tropical Park, Martinez Preserve, and
Crandon Park. The reviewer also suggested the rule should identify the
separate parcels within the Richmond Pinelands complex (i.e., Ram
Development Corporation, Martinez Pineland Preserve, Larry and Penny
Thompson Park, Zoo Miami, University of Florida, and those owned by the
Department of Defense (DOD)).
Our Response: The Service appreciates the new information. We have
updated the tables, and associated text, summarizing the status and
trends of the known occurrences of Linum arenicola and Argythamnia
blodgettii (Tables 3 and 4, above).
(2) Comment: Two peer reviewers and one public commenter identified
a recent publication by Ramirez-Amezcua and Steinman (2013) that
included a treatment of the Argythamnia subgenus Ditaxis in Mexico,
stating that the range of A. argothamnoides includes Florida, which may
bring into question the validity of A. blodgettii as a valid taxon. One
reviewer concluded that after reading the published information on the
subject, he did not find compelling information to suggest that Florida
A. blodgettii populations are synonymous with Argythamnia spp. outside
of Florida. This reviewer also recommended that the Service treat A.
blodgettii as a distinct species, endemic to Florida.
Our Response: The Service has reviewed Ramirez-Amezcua and Steinman
(2013) and additional literature relating to the taxonomy of
Argythamnia blodgettii. As stated in the ``Taxonomy'' sections of this
rule and the proposed rule, there is a history of changes to the
classification of this plant, with many based on studies that do not
include samples from across the plant's range, including the recent
publication suggesting that Argythamnia blodgettii is synonymous with
the wider ranging Ditaxis argothamnoides. However, the Service accepts
the treatment of A. blodgettii as a distinct species and therefore does
not find a compelling justification to remove the species from
consideration for listing under the Act.
(3) Comment: One reviewer commented on the need to include
information about genetic studies in the document.
Our Response: No genetic studies of Chamaecrista lineata var.
keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, or
Argythamnia blodgettii have been conducted.
(4) Comment: One reviewer disagreed with our statement that there
is no regulatory protection for State-listed plants on private lands
through Florida Administrative Code (FAC) 5B-40.
Our Response: The Service apologizes for mischaracterizing the
regulatory protections provided through FAC 5B-40. We have corrected
this, and describe the protections in detail in this final rule under
Factor D. The Inadequacy of Existing Regulatory Mechanisms, below.
(5) Comment: One reviewer suggested future research in best
practices for mowing areas that support Chamaecrista lineata var.
keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and
Argythamnia blodgettii.
Our Response: The Service agrees that the best mowing practices
should be investigated to support the species. This is a topic that
will be addressed in the recovery planning process.
[[Page 66847]]
(6) Comment: One reviewer provided new information from an ongoing
study about the direct and indirect effects of mosquito insecticide
spray on flower visitors and reproductive fitness of Chamaecrista
lineata var. keyensis and Linum arenicola in the lower Florida Keys. In
addition, two public commenters took issue with the section of the
proposed rule that discussed mosquito control pesticide applications as
a factor affecting pollinators of Chamaecrista lineata var. keyensis,
Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia
blodgettii. They asserted that the Service made incorrect statements
regarding the frequency and amount of mosquito control adulticide
treatments in South Florida. These public commenters requested that any
mention of pesticide effects on pollinators be removed from this final
rule.
Our Response: The Service appreciates the new information provided
by the peer reviewer. Data from ongoing studies in the lower Florida
Keys of L. arenicola flower visitor observations show that sites not
treated with adulticides had slightly higher fruit set rates than
treated sites and pollinator-excluded experimental trials. Several
species of small bees were observed frequenting flowers at untreated
sites, while visitation was much less frequent at the treated site.
Extensive studies in the Florida Keys suggest that broad spectrum
insecticides negatively affect nontarget invertebrates, including
pollinators (Hennessey 1991; Eliazar and Emmel 1991; Kevan et al. 1997;
Salvato 2001; Bargar 2011; Hoang et al. 2011). In addition, pesticides
have been shown to drift into adjacent undisturbed habitat that serves
as a refuge for native biota (Hennessey 1992; Pierce et al. 2005; Zhong
et al. 2010; Bargar 2011). These pesticides can be fatal to nontarget
invertebrates that move between urban and forest habitats, altering
ecological processes within forest communities (Kevan and Plowright
1989, 1995; Liu and Koptur 2003).
The Service believes that pesticide spraying may be a factor
affecting the reproductive success of Chamaecrista lineata var.
keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and
Argythamnia blodgettii. However, we acknowledge that pesticide spraying
practices by the Florida Keys Mosquito Control District (FKMCD) at
National Key Deer Refuge (NKDR) have changed over the years to reduce
pesticide use. Since 2003, expanded larvicide treatments to surrounding
islands have significantly reduced adulticide use on Big Pine Key, No
Name Key, and the Torch Keys. In addition, the number of aerially
applied naled (Dibrom[supreg]) treatments allowed on NKDR has been
limited since 2008 (FKMCD 2012, pp. 10-11). Zones that include the core
habitat used by pine rockland butterflies, and several linear miles of
pine rocklands habitat within the Refuge-neighborhood interface, were
excluded from truck spray applications (no-spray zones) (Anderson 2012,
pers. comm.; Service 2012, p. 32). These exclusions and buffer zones
encompass over 95 percent of extant croton distribution on Big Pine
Key, and include the majority of known recent and historical Florida
leafwing population centers on the island (Salvato 2012, pers. comm.).
Accordingly, the Service commends the FKMCD for its cooperation in
recovering endangered butterflies and plants. Nevertheless, we are
proceeding cautiously and have initiated a multi-year research project
to further investigate the level of impact pesticides have on these
four plants.
Federal Agency Comments
(7) Comment: The U.S. Navy expressed interest and a commitment to
work proactively with the Service to coordinate on the proposed listing
of Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii under the Act.
Naval Air Station (NAS) Key West, Florida, is subject to the NAS Key
West Integrated Natural Resources Management Plan (INRMP). The Navy
noted that the NAS Key West INRMP was acknowledged in the proposed
listing rule as providing a conservation benefit to Argythamnia
blodgettii habitat. The 2013 INRMP update identified several Monroe
County rare species, including Chamaecrista lineata var. keyensis,
Chamaesyce deltoidea ssp. serpyllum, and Linum arenicola, that do not
occur on NAS Key West properties. The Navy requested that the Service
coordinate with it prior to proposing critical habitat on Navy land for
any of these species and to fully consider the benefits imparted to
these species through INRMP implementation.
Our Response: We appreciate the U.S. Navy's interest and commitment
to work proactively with the Service to conserve Argythamnia
blodgettii. In particular, NAS Key West has been proactive in surveying
for these species and updating the NAS Key West INRMP to include
conservation measures for Argythamnia blodgettii. The Service will
coordinate early with NAS Key West regarding any critical habitat
proposal for Chamaecrista lineata var. keyensis, Chamaesyce deltoidea
ssp. serpyllum, Linum arenicola, or Argythamnia blodgettii.
Comments From the State
We received comments from a peer reviewer who is employed by the
Florida Forest Service. Those comments are addressed above under Peer
Reviewer Comments in our responses to Comments (3) and (4).
Public Comments
(8) Comment: One commenter opposed the proposed listing of the
plants on Big Pine Key, Florida. While the commenter generally agreed
with the field data for the Chamaecrista lineata var. keyensis,
Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia
blodgettii, the commenter asserted the habitat can no longer sustain
these and other federally protected endangered species going forward.
The commenter described several alterations, including drainage canals
and shallow wells for drainage, that they asserted have permanently
damaged the freshwater lens (convex layer of groundwater on top of a
layer of denser saltwater) in the Florida Keys. These alterations and
sea level rise have permanently changed the natural lens and the amount
of freshwater available to these species, particularly in times of
drought or following a major hurricane event.
Our Response: The Service acknowledges the challenges faced by the
Florida Keys due to salinization and sea level rise. These factors are
discussed at length in this final rule under Factor E. Other Natural or
Manmade Factors Affecting Its Continued Existence, below. In addition,
the Service agrees habitat loss or degradation is a factor that
threatens Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii. However, we
disagree that habitat on Big Pine Key can no longer sustain these or
other federally protected endangered species going forward. Canals,
which occur throughout a large portion of Big Pine Key, have allowed
saltwater intrusion into upland areas of the island for decades,
threatening upland ecosystems. However, habitat restoration is ongoing
across Big Pine Key, particularly within the pine rocklands and
rockland hammocks. These restoration efforts are attempting to protect
the freshwater lens required by native vegetation; this includes
filling or plugging drainage canals to reduce or halt seawater
intrusion into upland areas.
[[Page 66848]]
Summary of Changes From the Proposed Rule
None of the new information we received during the comment period
on the proposed rule changes our determinations in this final rule for
these four plants. Most of the changes are editorial in nature, and are
described above in the Background section of this rule. However, based
on comments we received from peer reviewers and the public, we make the
following substantive changes:
We update the status of several populations of Linum
arenicola and Argythamnia blodgettii;
We update the discussion of the taxonomy of A. blodgettii
to take into consideration a recent publication; and
We update our discussion of pesticide applications and
pollinators to reflect current application limitations now in effect on
Big Pine Key.
Summary of Factors Affecting the Species
The Act directs us to determine whether any species is an
endangered species or a threatened species because of any one of five
factors affecting its continued existence. In this section, we
summarize the biological condition of each of the plant species and its
resources, and the factors affecting them, to assess the species'
overall viability and the risks to that viability.
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii have experienced
substantial destruction, modification, and curtailment of their
habitats and ranges. Specific threats to these plants under this factor
include habitat loss, fragmentation, and modification caused by
development (i.e., conversion to both urban and agricultural land uses)
and inadequate fire management. Each of these threats and its specific
effects on these plants are discussed in detail below.
Human Population Growth, Development, and Agricultural Conversion
The modification and destruction of the habitats that support
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii has been extreme
in most areas of Miami-Dade and Monroe Counties, thereby reducing these
plants' current ranges and abundance in Florida. The pine rocklands
community of south Florida, in which all four plants primarily occur,
is critically imperiled locally and globally (FNAI 2012, p. 27).
Destruction of pine rocklands and rockland hammocks has occurred since
the beginning of the 1900s. Extensive land clearing for human
population growth, development, and agriculture in Miami-Dade and
Monroe Counties has altered, degraded, or destroyed thousands of acres
of these once abundant ecosystems.
In Miami-Dade County, development and agriculture have reduced pine
rocklands habitat by 90 percent in mainland south Florida. Pine
rocklands habitat decreased from approximately 74,000 hectares (ha)
(183,000 acres (ac)) in the early 1900s, to only 8,140 ha (20,100 ac)
in 1996 (Kernan and Bradley 1996, p. 2). The largest remaining intact
pine rocklands (approximately 2,313 ha (5,716 ac)) is located on Long
Pine Key in Everglades National Park (ENP). Outside of ENP, only about
1 percent of the pine rocklands on the Miami Rock Ridge have escaped
clearing, and much of what is left are small remnants scattered
throughout the Miami metropolitan area, isolated from other natural
areas (Herndon 1998, p. 1).
Similarly, most of the pine rocklands in the Florida Keys (Monroe
County) have been impacted (Hodges and Bradley 2006, p. 6). Pine
rocklands historically covered 1,049 ha (2,592 ac) of Big Pine Key
(Folk 1991, p. 188), the largest area of pine rocklands in the Florida
Keys. Pine rocklands now cover approximately 582 ha (1,438 ac) of the
island, a reduction of 56 percent (Bradley and Saha 2009, p. 3). There
were no estimates of pine rocklands area on the other islands
historically, but each contained much smaller amounts of the habitat
than Big Pine Key. Remaining pine rocklands on Cudjoe Key cover 72 ha
(178 ac), Little Pine has 53 ha (131 ac), No Name has 56 ha (138 ac),
and Sugarloaf has 38 ha (94 ac). The total area of remaining pine
rocklands in the Florida Keys is approximately 801 ha (1,979 ac).
Currently, about 478 ha (1,181 ac) (82 percent) of the pine rocklands
on Big Pine Key, and most of the pine rocklands on these other islands,
are protected within the NKDR and properties owned by the Nature
Conservancy, the State of Florida, and Monroe County (Bradley and Saha
2009, pp. 3-4). Based on the data presented above, the total remaining
acreage of pine rocklands in Miami-Dade and Monroe Counties is now
8,981 ha (22,079 ac) (approximately 8,140 ha (20,100 ac) in Miami-Dade
County, and 801 ha (1,979 ac) in the Florida Keys (Monroe County)).
The marl prairies that also support Linum arenicola have similarly
been destroyed by the rapid development of Miami-Dade and Monroe
Counties. At least some of the occurrences reported from this habitat
may be the result of colonization that occurred after they were
artificially dried-out due to local or regional drainage.
Likewise, habitat modification and destruction from residential and
commercial development have severely impacted rockland hammocks, and
coastal berm, that support Argythamnia blodgettii. Rockland hammocks
were once abundant in Miami-Dade and Monroe Counties but are now
considered imperiled locally and globally (FNAI 2010x, pp. 24-26). The
tremendous development and agricultural pressures in south Florida have
resulted in significant reductions of rockland hammock, which is also
susceptible to fire, frost, hurricane damage, and groundwater reduction
(Phillips 1940, p. 167; Snyder et al. 1990, pp. 271-272; FNAI 2010, pp.
24-26).
Pine rocklands, rockland hammock, marl prairie, and coastal
habitats on private land remain vulnerable to development, which could
lead to the loss of populations of these four species. As noted
earlier, all four plants have been impacted by development. The sites
of Small's 1907 and 1911 L. arenicola collections in Miami-Dade County
are now agricultural fields (Kernan and Bradley 1996, p. 4). A pine
rocklands site that supported L. arenicola on Vistalmar Street in Coral
Gables (Miami-Dade County) was cleared and developed in 2005, as part
of the growing the Cocoplum housing development. A second pine
rocklands site that supported L. arenicola, located on private land on
Old Cutler Road, was developed into the Palmetto Bay Village Center. L.
arenicola has not been observed at either site since they were
developed. A former marl prairie site supporting a sizable population
of L. arenicola near Old Cutler Road and Allapatah Drive (SW 112 Ave)
in Miami-Dade County was extirpated when the site was developed in the
1990s (Bradley and van der Heiden 2013, pp. 6-12, 19). The Boca Chica
Key population of L. arenicola was also likely lost due to development
(Hodges and Bradley 2006, p. 48).
Bradley and Gann (1999, p. 6) list 12 populations of Argythamnia
blodgettii in Miami-Dade County that were lost when the site that
supported them was developed. An A. blodgettii population on Key West
was likely lost due to the near complete urbanization of the island
(Hodges and Bradley 2006, p. 43). Any
[[Page 66849]]
development related to the Boy Scout camp on Big Munson Island is a
potential threat to the largest population A. blodgettii.
The largest Linum arenicola population in Miami-Dade County is
located on property owned by the Miami-Dade County Homeless Trust. U.S.
Special Operations Command South Headquarters (SOCSOUTH), a unified
command of all four services of DOD, has entered into a 50-year
agreement with Miami-Dade County to lease this 90-ac (36.4-ha) area,
where they are building a permanent headquarters on approximately 28 ac
(11.3 ha) (DOD 2009, p. 1). As stated above, the population of L.
arenicola is spread across the site and was estimated at 74,000 plants
in 2009 (Bradley 2009, p. 3). In consultation with the Service, the DOD
developed a plan that avoided the majority of the population with
accompanying protection and management of approximately 57,725
individuals of sand flax (about 78 percent of the estimated onsite
population) (Service 2011, p. 13). The plan will manage 5.95 ha (14.7
ac) of habitat, though most of it is scraped, and only a small portion
has a pine canopy (Van der Heiden and Johnson 2013, p. 2). An
additional 1.3 ha (3.2 ac) is being managed and supports 13,184
individuals of sand flax (about 18 percent of the estimated onsite
population) (Service 2011, p. 13).
Currently there are plans to develop a 55-ha (137-ac) privately-
owned portion of the largest remaining area of pine rocklands habitat
in Miami-Dade County, the Richmond pine rocklands, with a shopping
center and residential construction (RAM 2014, p. 2). Bradley and Gann
(1999, p. 4) called the 345-ha (853-ac) Richmond pine rocklands, ``the
largest and most important area of pine rockland in Miami-Dade County
outside of Everglades National Park.'' Populations of Argythamnia
blodgettii and Linum arenicola, along with numerous federally listed
species, occur in habitat adjacent to the area slated for development.
The Miami-Dade County Department of Regulatory and Economic Resources
(RER) has completed a management plan for county-owned portions of the
Richmond pine rocklands (Martinez Pineland Preserve, Larry and Penny
Thompson Park) under a grant from the Service and is leading the
restoration and management of these areas (Bradley and Gann 1999, p.
4). The developer has proposed to enter into a habitat conservation
plan in conjunction with their plans to develop their portion of the
site and was required by Miami-Dade County Natural Forest Community
(NFC) regulations to set aside and manage 15 ha (39 ac) of pine
rocklands and 2 ha (4 ac) of rockland hammock. A second project that
would result in the loss of pine rocklands habitat is also proposed for
the Richmond pine rocklands. It includes expanding the Miami Zoo
complex to develop an amusement park and large retail mall.
Approximately 25 percent of extant Linum arenicola occurrences (3
of 12 sites), and 40 percent of extant Argythamnia blodgettii
occurrences (14 of 35 sites), are located on private land; no extant
populations of Chamaecrista lineata var. keyensis or Chamaesyce
deltoidea ssp. serpyllum are located entirely on private land. It is
possible that the plants on private lands will be lost from most of
these sites in the future with increased pressure from development and
the other threats described below.
Argythamnia blodgettii is the only one of the four plant species
that occurs in ENP, where a population of over 2,000 plants is stable,
and prescribed fire and other management activities that benefit A.
blodgettii are conducted on a regular basis.
Most pine rocklands and rockland hammock habitat is now limited to
public conservation lands, where future development and habitat
alteration are less likely than on private lands. However, public lands
could be sold off (or leased) in the future and become more likely to
be developed or altered in a way that negatively impacts the habitat.
For example, at the SOCSOUTH site noted above (leased to DOD by Miami-
Dade County), ongoing development of headquarters buildings SOCSOUTH
has resulted in the loss of L. arenicola and pine rocklands habitat
(Bradley and van der Heiden 2013, pp. 8-10). Construction of visitor
facilities such as parking lots, roads, trails, and buildings can
result in habitat loss on public lands that are set aside as preserves
or parks.
Roadside populations of Chamaecrista lineata var. keyensis,
Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia
blodgettii are vulnerable to habitat loss and modification stemming
from infrastructure projects such as road widening, and installation of
underground cable, sewer, and water lines. The Lower Sugarloaf Key
population of Linum arenicola was impacted by repaving of the road,
which placed asphalt on top of and adjacent to the population (Hodges
and Bradley 2006, p. 41).
Although no entire populations of Chamaecrista lineata var.
keyensis or Chamaesyce deltoidea ssp. serpyllum have been extirpated by
habitat loss due to development, the size and extent of these
populations have been reduced on Big Pine Key (and surrounding islands
for Chamaecrista lineata var. keyensis). The total area of pine
rocklands on Big Pine Key has decreased by 56 percent from 1955 to the
present (Bradley and Saha 2009, p. 3).
The human population within Miami-Dade County is currently greater
than 2.4 million people, and is expected to grow to more than 4 million
by 2060, an annual increase of roughly 30,000 people (Zwick and Carr
2006, p. 20). Overall, the human population in Monroe County is
expected to increase from 79,589 to more than 92,287 people by 2060
(Zwick and Carr 2006, p. 21). All vacant land in the Florida Keys is
projected to be developed by then, including lands currently
inaccessible for development, such as islands not attached to the
Overseas Highway (U.S. 1) (Zwick and Carr 2006, p. 14). However, in an
effort to address the impact of development on federally listed
species, Monroe County implemented a habitat conservation plan (HCP)
for Big Pine and No Name Keys in 2006. In order to fulfill the HCP's
mitigation requirements, the County has been actively acquiring parcels
of high-quality pine rocklands, such as The Nature Conservancy's 20-
acre Terrestris Tract on Big Pine Key, and managing them for
conservation. Although the HCP has helped to limit the impact of
development, land development pressure and habitat losses may resume
when the HCP expires in 2023. If the HCP is not renewed, residential or
commercial development could increase to pre-HCP levels.
While Miami-Dade and Monroe County both have developed a network of
public conservation lands that include pine rocklands, rockland
hammocks, marl prairies, and coastal habitats, much of the remaining
habitat occurs on private lands as well as publicly owned lands not
managed for conservation. Species occurrences and suitable habitat
remaining on these lands are threatened by habitat loss and
degradation, and threats are expected to accelerate with increased
development. Further losses will seriously affect the four plant
species' ability to persist in the wild and decrease the possibility of
their recovery or recolonization.
Habitat Fragmentation
The remaining pine rocklands in the Miami metropolitan area are
severely fragmented and isolated from each other by vast areas of
development. Remaining pine rockland areas in the Florida Keys are
fragmented and are located on small islands separated by
[[Page 66850]]
ocean. Habitat fragmentation reduces the size of plant populations and
increases spatial isolation of remnants. Barrios et al. (2011, p. 1062)
investigated the effects of fragmentation on a pine rocklands plant,
Angadenia berteroi (pineland golden trumpet), which is recognized by
the State of Florida as threatened, and found that abundance and
fragment size were positively related. Possley et al. (2008, p. 385)
studied the effects of fragment size on species composition in south
Florida pine rocklands, and found that plant species richness and
fragment size were positively correlated (although some small fragments
supported nearly as many species as the largest fragment). Composition
of fragmented habitat typically differs from that of intact forests; as
isolation and edge effects increase, there is increased abundance of
disturbance-adapted species (weedy species; nonnative, invasive
species) and lower rates of pollination and propagule dispersal
(Laurence and Bierregaard 1997, pp. 347-350; Noss and Csuti 1997, pp.
284-299). The degree to which fragmentation threatens the dispersal
abilities of Chamaecrista lineata var. keyensis, Chamaesyce deltoidea
ssp. serpyllum, Linum arenicola, and Argythamnia blodgettii is unknown.
In the historical landscape, where pine rocklands occurred within a
mosaic of wetlands, water may have acted as a dispersal vector for all
pine rocklands seeds. In the current, fragmented landscape, this type
of dispersal would no longer be possible for any of the Miami-Dade
populations. While additional dispersal vectors may include animals and
(in certain locations) mowing equipment, it is likely that
fragmentation has effectively reduced these plants' ability to disperse
and exchange genetic material.
While pollination research has not been conducted for Chamaesyce
deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia blodgettii,
research regarding other species and ecosystems, including Chamaecrista
lineata var. keyensis (discussed below), provides valuable information
regarding potential effects of fragmentation on these plants. Effects
of fragmentation on pollinators may include changes to the pollinator
community as a result of limitation of pollinator-required resources
(e.g., reduced availability of rendezvous plants, nesting and roosting
sites, and nectar/pollen); these changes may include changes to
pollinator community composition, species abundance and diversity, and
pollinator behavior (Rathcke and Jules 1993, pp. 273-275; Kremen and
Ricketts 2000, p. 1227; Harris and Johnson 2004, pp. 30-33). As a
result, plants in fragmented habitats may experience lower visitation
rates, which in turn may result in reduced seed production of the
pollinated plant (which may lead to reduced seedling recruitment),
reduced pollen dispersal, increased inbreeding, reduced genetic
variability, and ultimately reduced population viability (Rathcke and
Jules 1993, p. 275; Goverde et al. 2002, pp. 297-298; Harris and
Johnson 2004, pp. 33-34).
In addition to affecting pollination, fragmentation of natural
habitats often alters other ecosystems' functions and disturbance
regimes. Fragmentation results in an increased proportion of ``edge''
habitat, which in turn has a variety of effects, including changes in
microclimate and community structure at various distances from the edge
(Margules and Pressey 2000, p. 248), altered spatial distribution of
fire (greater fire frequency in areas nearer the edge) (Cochrane 2001,
pp. 1518-1519), and increased pressure from nonnative, invasive plants
and animals that may out-compete or disturb native plant populations.
Liu and Koptur (2003, p. 1184) reported decreases in Chamaecrista
lineata var. keyensis's seed production in urban areas of Big Pine Key
due to increased seed predation, compared with areas away from
development.
The effects of fragmentation on fire go beyond edge effects and
include reduced likelihood and extent of fires, and altered behavior
and characteristics (e.g., intensity) of those fires that do occur.
Habitat fragmentation encourages the suppression of naturally occurring
fires, and has prevented fire from moving across the landscape in a
natural way, resulting in an increased amount of habitat suffering from
these negative impacts. High fragmentation of small habitat patches
within an urban matrix discourages the use of prescribed fire as well
due to logistical difficulties (see ``Fire Management,'' below). Forest
fragments in urban settings are also subject to increased likelihood of
certain types of human-related disturbance, such as the dumping of
trash (Chavez and Tynon 2000, p. 405). The many effects of habitat
fragmentation may work in concert to threaten the local persistence of
a species; when a species' range of occurrence is limited, threats to
local persistence increase extinction risk.
Fire Management
One of the primary threats to Chamaecrista lineata var. keyensis,
Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia
blodgettii is habitat modification and degradation through inadequate
fire management, which includes both the lack of prescribed fire and
suppression of natural fires. Where the term ``fire-suppressed'' is
used below, it describes degraded pine rocklands conditions resulting
from a lack of adequate fire (natural or prescribed) in the landscape.
Historically, frequent (approximately twice per decade), lightning-
induced fires were a vital component in maintaining native vegetation
and ecosystem functioning within south Florida pine rocklands. A period
of just 10 years without fire may result in a marked decrease in the
number of herbaceous species due to the effects of shading and litter
accumulation (FNAI 2010, p. 63). Exclusion of fire for approximately 25
years will likely result in gradual hammock development over that time
period, leaving a system that is very fire-resistant if additional pre-
fire management (e.g., mechanical hardwood removal) is not undertaken.
Today, natural fires are unlikely to occur or are likely to be
suppressed in the remaining, highly fragmented pine rocklands habitat.
The suppression of natural fires has reduced the size of the areas that
burn, and habitat fragmentation has prevented fire from moving across
the landscape in a natural way. Without fire, successional climax from
pine rocklands to rockland hammock is rapid, and displacement of native
species by invasive, nonnative plants often occurs. Understory plants
such as Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii are shaded out
by hardwoods and nonnatives alike. Shading may also be caused by a
fire-suppressed pine canopy that has evaded the natural thinning
effects that fire has on seedlings and smaller trees. Whether the dense
canopy is composed of pine, hardwoods, nonnatives, or a combination,
seed germination and establishment are inhibited in fire-suppressed
habitat due to accumulated leaf litter, which also changes soil
moisture and nutrient availability (Hiers et al. 2007, pp. 811-812).
This alteration to microhabitat can also inhibit seedling establishment
as well as negatively influence flower and fruit production
(Wendelberger and Maschinski 2009, pp. 849-851), thereby reducing
sexual reproduction in fire-adapted species such as Chamaecrista
lineata var. keyensis, Chamaesyce deltoidea ssp. serpyllum, L.
arenicola, and A. blodgettii (Geiger 2002, pp. 78-79, 81-83).
After an extended period of inadequate fire management in pine
[[Page 66851]]
rocklands, it becomes necessary to control invading native hardwoods
mechanically, as excess growth of native hardwoods would result in a
hot fire, which can kill mature pines. Mechanical treatments cannot
entirely replace fire because pine trees, understory shrubs, grasses,
and herbs all contribute to an ever-increasing layer of leaf litter,
covering herbs and preventing germination, as discussed above. Leaf
litter will continue to accumulate even if hardwoods are removed
mechanically. In addition, the ashes left by fires provide important
post-fire nutrient cycling, which is not provided via mechanical
removal.
Federal (Service, NPS, FFS (Florida Forest Service)), State (FDEP,
FWC), and County land managers (Miami-Dade RER and NAM (the Natural
Areas Management division of Department of Parks, Recreation and Open
Spaces), and nonprofit organizations (Institute for Regional
Conservation (IRC), The Nature Conservancy (TNC)) implement prescribed
fire on public and private lands within the ranges of these four
plants. While management of some County conservation lands includes
regular burning, other lands remain severely fire-suppressed. Even in
areas under active management, some portions are typically fire-
suppressed.
Miami-Dade County: Implementation of a prescribed fire program in
Miami-Dade County has been hampered by a shortage of resources, as well
as by logistical difficulties and public concern related to burning
next to residential areas. Many homes have been built in a mosaic of
pine rocklands, so the use of prescribed fire in many places has become
complicated because of potential danger to structures and smoke
generated from the burns. Nonprofit organizations such as IRC have
similar difficulties in conducting prescribed burns due to difficulties
with permitting and obtaining the necessary permissions as well as
hazard insurance limitations (Gann 2013a, pers. comm.). Few private
landowners have the means or desire to implement prescribed fire on
their property, and doing so in a fragmented urban environment is
logistically difficult and may be costly.
All occurrences of Linum arenicola and Argythamnia blodgettii in
Miami-Dade County are affected by some degree of inadequate fire
management of pine rocklands and marl prairie habitat, with the primary
threat being the modification and loss of habitat due to an increase in
shrub and hardwood dominance, eliminating suitable conditions for the
four plants, and eventual succession to rockland hammock.
In Miami-Dade County, Linum arenicola occurred along the south edge
of Bauer Drive on the northern border of a pine rockland owned by
Miami-Dade County. The property is occupied by a communications tower,
and is not a managed preserve. Kernan and Bradley (1996) reported eight
plants. At the time (1992 through 1996), the road shoulder was
dominated by native grasses. Since then, native canopy hardwoods have
invaded the site and eliminated the sunny conditions required by L.
arenicola. It has not been seen since, despite multiple surveys between
1997 and 2012, and is considered to be extirpated. L. arenicola was
discovered at Camp Owaissa Bauer by George N. Avery in 1983. Since that
time, the pine rocklands habitat where he found the plants in the park
suffered extremely heavy hardwood recruitment due to fire suppression.
Despite recent hardwood control and reintroduction of fire, no plants
have been relocated. Bradley and Gann (1999, pp. 71-72) suggested that
the lack of fires in most forest fragments in Miami-Dade County during
the last century may be one of the reasons why L. arenicola occurs
primarily in disturbed areas.
Monroe County (Florida Keys): Fire management of pine rocklands of
the lower Florida Keys, most of which are within NKDR, is hampered by a
shortage of resources, technical challenges, and expense of conducting
prescribed fire in a matrix of public and private ownership.
Residential and commercial properties are embedded within or in close
proximity to pine rocklands habitat (Snyder et al. 2005, p. 2; C.
Anderson 2012a, pers. comm.). As a result, hand or mechanical
vegetation management may be necessary at select locations on Big Pine
Key (Emmel et al. 1995, p. 11; Minno 2009, pers. comm.; Service 2010,
pp. 1-68) to maintain or restore pine rocklands. Mechanical treatments
may be less beneficial than fire because they do not quickly convert
debris to nutrients, and remaining leaf litter may suppress seedling
development; fire has also been found to stimulate seedling germination
(C. Anderson 2010, pers. comm.). Because mechanical treatments may not
provide the same ecological benefits as fire, NKDR continues to focus
efforts on conducting prescribed fire where possible (C. Anderson
2012a, pers. comm.). However, the majority of pine rocklands within
NKDR are several years behind the ideal fire return interval (5-7
years) suggested for this ecosystem (Synder et al. 2005, p. 2; Bradley
and Saha 2011, pp. 1-16). Tree ring and sediment data show that pine
rocklands in the lower Keys have burned at least every 5 years and
sometimes up to three times per decade historically (Albritton 2009, p.
123; Horn et al. 2013, pp. 1-67; Harley 2012, pp. 1-246). From 1985 to
1992, prescribed burns were conducted in the NKDR mainly for fuel
reduction. There was no prescribed burning by Service staff in the NKDR
from 1992-1997, in part because not enough was known about the
ecological effects of prescribed fire in this system (Snyder et al.
1990, p. 2).
All occurrences of Chamaecrista lineata var. keyensis, Chamaesyce
deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia blodgettii
in the Florida Keys are affected by some degree of inadequate fire
management of pine rocklands habitat, with the primary threat being the
modification and loss of habitat due to an increase in shrub and
hardwood dominance, eliminating suitable conditions for the four
plants, and eventual succession to rockland hammock.
Prescribed fire management over the past decade has not been
sufficient to reverse long-term declines in Chamaecrista lineata var.
keyensis, Chamaesyce deltoidea ssp. serpyllum, or Linum arenicola on
Big Pine Key. Prescribed fire activity on Big Pine Key and adjacent
islands within NKDR appears to be insufficient to prevent loss of pine
rocklands habitat (Carlson et al. 1993, p. 914; Bergh and Wisby 1996,
pp. 1-2; O'Brien 1998, p. 209; Bradley and Saha 2009, pp. 28-29;
Bradley et al. 2011, pp. 1-16). As a result, many of the pine rocklands
across NKDR are being compromised by succession to rockland hammock
(Bradley and Saha 2009, pp. 28-29; Bradley et al. 2011, pp. 1-16).
Conservation Efforts To Reduce the Present or Threatened Destruction,
Modification, or Curtailment of Habitat or Range
Miami-Dade County Environmentally Endangered Lands (EEL) Covenant
Program: In 1979, Miami-Dade County enacted the Environmentally
Endangered Lands (EEL) Covenant Program, which reduces taxes for
private landowners of natural forest communities (NFCs; pine rocklands
and tropical hardwood hammocks) who agree not to develop their property
and manage it for a period of 10 years, with the option to renew for
additional 10-year periods (Service 1999, p. 3-177). Although these
temporary conservation easements provide valuable protection for their
duration, they are not considered under the discussion of Factor D,
below, because they are voluntary agreements and not regulatory
[[Page 66852]]
in nature. Miami-Dade County currently has approximately 59 pine
rocklands properties enrolled in this program, preserving 69.4 ha (172
ac) of pine rocklands habitat (Johnson 2012, pers. comm.). The program
also has approximately 21 rockland hammocks properties enrolled in this
program, preserving 20.64 ha (51 ac) of rockland hammock habitat
(Joyner 2013b, pers. comm.). The vast majority of these properties are
small, and many are in need of habitat management such as prescribed
fire and removal of nonnative, invasive plants. Thus, while EEL
covenant lands have the potential to provide valuable habitat for these
plants and reduce threats in the near term, the actual effect of these
conservation lands is largely determined by whether individual
landowners follow prescribed EEL management plans and NFC regulations
(see ``Local'' under Factor D discussion, below).
Fee Title Properties: In 1990, Miami-Dade County voters approved a
2-year property tax to fund the acquisition, protection, and
maintenance of natural areas by the EEL Program. The EEL Program
purchases and manages natural lands for preservation. Land uses deemed
incompatible with the protection of the natural resources are
prohibited by current regulations; however, the County Commission
ultimately controls what may happen with any County property, and land
use changes may occur over time (Gil 2013b, pers. comm.). To date, the
Miami-Dade County EEL Program has acquired a total of approximately 313
ha (775 ac) of pine rocklands, and 95 ha (236 ac) of rockland hammocks
(Guerra 2015, pers. comm.; Gil 2013b, pers. comm.). The EEL Program
also manages approximately 314 ha (777 ac) of pine rocklands, and 639
ha (1,578 ac) of tropical hardwood and rockland hammocks owned by the
Miami-Dade County Parks, Recreation and Open Spaces Department,
including some of the largest remaining areas of pine rocklands habitat
on the Miami Rock Ridge outside of ENP (e.g., Larry and Penny Thompson
Park, Zoo Miami pinelands, Navy Wells Pineland Preserve), and some of
the largest remaining areas of tropical hardwood and rockland hammocks
(e.g., Matheson Hammock Park, Castellow Hammock Park, Deering Estate
Park and Preserves).
Conservation efforts in Miami's EEL Preserves have been underway
for many years. In Miami-Dade County, conservation lands are and have
been monitored by Fairchild Tropical Botanic Garden (FTBG) and IRC, in
coordination with the EEL Program, to assess habitat status and
determine any changes that may pose a threat to or alter the abundance
of these species. Impacts to habitat (e.g., canopy) via nonnative
species and natural stochastic events are monitored and actively
managed in areas where the taxon is known to occur. These programs are
long-term and ongoing in Miami-Dade County; however, programs are
limited by the availability of annual funding.
Since 2005, the Service has funded IRC to facilitate restoration
and management of privately owned pine rocklands habitats in Miami-Dade
County. These programs included prescribed burns, nonnative plant
control, light debris removal, hardwood management, reintroduction of
pines where needed, and development of management plans. One of these
programs, called the Pine Rockland Initiative, includes 10-year
cooperative agreements between participating landowners and the
Service/IRC to ensure restored areas will be managed appropriately
during that time. Although most of these objectives have been achieved,
IRC has not been able to conduct the desired prescribed burns, due to
logistical difficulties as discussed earlier (see ``Fire Management,''
above).
Connect to Protect Program: FTBG, with the support of various
Federal, State, and local agencies and nonprofit organizations, has
established the ``Connect to Protect Network.'' The objective of this
program is to encourage widespread participation of citizens to create
corridors of healthy pine rocklands by planting stepping stone gardens
and rights-of-way with native pine rocklands species, and restoring
isolated pine rocklands fragments. By doing this, FTBG hopes to
increase the probability that pollination and seed dispersal vectors
can find and transport seeds and pollen across developed areas that
separate pine rocklands fragments to improve gene flow between
fragmented plant populations and increase the likelihood that these
plants will persist over the long term. Although these projects may
serve as valuable components toward the conservation of pine rocklands
species and habitat, they are dependent on continual funding, as well
as participation from private landowners, both of which may vary
through time.
National Wildlife Refuges: The National Wildlife Refuge System
Improvement Act of 1997 (16 U.S.C. 668dd note) and the Fish and
Wildlife Service Manual (601 FW 3, 602 FW 3) require maintaining
biological integrity and diversity, require comprehensive conservation
planning for each refuge, and set standards to ensure that all uses of
refuges are compatible with their purposes and the Refuge System's
wildlife conservation mission. The comprehensive conservation plans
(CCPs) address conservation of fish, wildlife, and plant resources and
their related habitats, while providing opportunities for compatible
wildlife-dependent recreation uses. An overriding consideration
reflected in these plans is that fish and wildlife conservation has
first priority in refuge management, and that public use be allowed and
encouraged as long as it is compatible with, or does not detract from,
the Refuge System mission and refuge purpose(s). The CCP for the Lower
Florida Keys National Wildlife Refuges (NKDR, Key West National
Wildlife Refuge, and Great White Heron National Wildlife Refuge)
provides a description of the environment and priority resource issues
that were considered in developing the objectives and strategies that
guide management over the next 15 years. The CCP promotes the
enhancement of wildlife populations by maintaining and enhancing a
diversity and abundance of habitats for native plants and animals,
especially imperiled species that are found only in the Florida Keys.
The CCP also provides for obtaining baseline data and monitoring
indicator species to detect changes in ecosystem diversity and
integrity related to climate change. The CCP provides specifically for
maintaining and expanding populations of candidate plant species,
including Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii, all four of
which are found in this refuge complex.
Department of Defense Lands: The Sikes Act requires the DOD to
develop and implement integrated natural resources management plans
(INRMPs) for military installations across the United States (see also
Factor D discussion, below). INRMPs are prepared in cooperation with
the Service and State fish and wildlife agencies to ensure proper
consideration of fish, wildlife, and habitat needs. The DOD has an
approved INRMP for Key West Naval Air Station (KWNAS) on Boca Chica Key
that includes measures that will protect and enhance Argythamnia
blodgettii habitat, including nonnative species control (DOD 2014, p.
69). Furthermore, DOD is currently preparing an INRMP for Homestead Air
Reserve Base (HARB) and SOCSOUTH. A previous biological opinion
(Service 2011, entire) required SOCSOUTH to protect and manage 7.4 ha
(18.3 ac) of pine rocklands habitat
[[Page 66853]]
and 70,909 individuals of Linum arenicola (approximately 96 percent of
the estimated onsite population) based on 2009 survey data. A
conservation easement was established over the protected areas, and DOD
has provided funds for management of the site, including fencing and
nonnative species control.
Summary of Factor A
We have identified a number of threats to the habitat of
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii that have
operated in the past, are impacting these species now, and will
continue to impact them in the future. Habitat loss, fragmentation, and
degradation, and associated pressures from increased human population,
are major threats; these threats are expected to continue, placing
these plants at greater risk. All four plants may be impacted when pine
rocklands are converted to other uses or when lack of fire causes the
conversion to hardwood hammocks or other unsuitable habitat conditions.
Any populations of these species found on private property could be
destroyed by development; the limited pine rocklands, rockland hammock,
and coastal berm habitat on public lands can also be affected by
development of recreational facilities or infrastructure projects.
Although efforts are being made to conserve publicly and privately
owned natural areas and apply prescribed fire, the long-term effects of
large-scale and wide-ranging habitat modification, destruction, and
curtailment will last into the future, while ongoing habitat loss due
to population growth, development, and agricultural conversion
continues to pose a threat. Therefore, based on the best information
available, we have determined that the threats to the four plants from
habitat destruction, modification, or curtailment are occurring
throughout the entire range of the species and are expected to continue
into the future.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
The best available data do not indicate that overutilization for
commercial, recreational, scientific, or educational purposes is a
threat to Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, or Argythamnia blodgettii. Threats to these
plants related to other aspects of recreation and similar human
activities (i.e., not related to overutilization) are discussed under
Factor E, below.
Factor C. Disease or Predation
No diseases or incidences of predation have been reported for
Chamaesyce deltoidea ssp. serpyllum or Argythamnia blodgettii.
Key deer are known to occasional browse plants indiscriminately,
including Chamaecrista lineata var. keyensis and Linum arenicola. Key
deer do not appear to feed on Argythamnia blodgettii, probably due to
potential toxicity (Hodges and Bradley 2006, p. 19).
Seed predation by an insect occurs in Chamaecrista lineata var.
keyensis, and seems to be exacerbated by habitat fragmentation.
Individuals at the urban edge suffer higher insect seed predation than
those inside the forest (Liu and Koptur 2003, p. 1184).
While seed predation and occasional Key deer browsing may be a
stressor, they do not appear to rise to the level of threat at this
time. Therefore, the best available data do not indicate that disease
or predation is a threat to Chamaecrista lineata var. keyensis or Linum
arenicola.
Factor D. The Inadequacy of Existing Regulatory Mechanisms
Under this factor, we examine whether threats to these plants are
discussed under the other factors are continuing due to an inadequacy
of an existing regulatory mechanism. Section 4(b)(1)(A) of the Act
requires the Service to take into account ``those efforts, if any,
being made by any State or foreign nation, or any political subdivision
of a State or foreign nation, to protect such species.'' In relation to
Factor D under the Act, we interpret this language to require the
Service to consider relevant Federal, State, and tribal laws,
regulations, and other such mechanisms that may minimize any of the
threats we describe in threat analyses under the other four factors, or
otherwise enhance conservation of the species. We give strongest weight
to statutes and their implementing regulations and to management
direction that stems from those laws and regulations. Examples are
State governmental actions enforced under a State statute or
constitution, and Federal actions authorized by statute.
Having evaluated the impact of the threats as mitigated by any such
conservation efforts, we analyze under Factor D the extent to which
existing regulatory mechanisms are inadequate to address the specific
threats to the species. Regulatory mechanisms, if they exist, may
reduce or eliminate the impacts from one or more identified threats. In
this section, we review existing Federal, State, and local regulatory
mechanisms to determine whether they effectively reduce or remove
threats to Chamaecrista lineata var. keyensis, Chamaesyce deltoidea
ssp. serpyllum, Linum arenicola, and Argythamnia blodgettii.
Federal
As Federal candidate species, the four plants are afforded some
protection through sections 7 and 10 of the Act and associated policies
and guidelines. Service policy requires that candidate species be
treated as proposed species for purposes of intra-Service consultations
and conferences where the Service's actions may affect candidate
species. Other Federal action agencies (e.g., NPS) are to consider the
potential effects (e.g., prescribed fire, pesticide treatments) to
these plants and their habitat during the consultation and conference
process. Applicants and Federal action agencies are encouraged to
consider candidate species when seeking incidental take for other
listed species and when developing habitat conservation plans. However,
candidate species do not receive the same level of protection that a
listed species does under the Act.
Populations of Argythamnia blodgettii within ENP are protected by
NPS regulations at 36 CFR 2.1, which prohibit visitors from harming or
removing plants, listed or otherwise, from ENP. However, the
regulations do not address actions taken by NPS that cause habitat loss
or modification.
As discussed above under Factor A, the CCPs for the Lower Florida
Keys National Wildlife Refuge and the Crocodile Lake National Wildlife
Refuge provide for Chamaecrista lineata var. keyensis, Chamaesyce
deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia blodgettii.
Linum arenicola occurs on DOD lands at HARB and SOCSOUTH. L. arenicola
and A. blodgettii may occur on Federal lands within the Richmond Pine
rocklands, including lands owned by the U.S. Coast Guard.
As discussed under Factor A, above, the DOD has an approved INRMP
for KWNAS on Boca Chica Key that includes measures that will protect
and enhance Argythamnia blodgettii habitat, including nonnative species
control (DOD 2014, p. 69). Furthermore, as also discussed above, DOD is
currently preparing an INRMP for HARB and SOCSOUTH, and a 2011 Service
biological opinion requires SOCSOUTH to protect and manage 7.4 ha (18.3
ac)
[[Page 66854]]
of pine rocklands habitat and 70,909 individuals of Linum arenicola.
However, certain populations of the four plants occur on State- or
county-owned properties, and development of these areas will likely
require no Federal permit or other authorization. Therefore, projects
that affect the plants on State- and county-owned lands do not have
Federal oversight, such as complying with the National Environmental
Policy Act (NEPA; 42 U.S.C. 4321 et seq.), unless the project has a
Federal nexus (Federal funding, permits, or other authorizations).
Therefore, the four plants have no direct Federal regulatory protection
in these areas.
State
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii are listed on
the Regulated Plant Index (Index) as endangered under chapter 5B-40,
Florida Administrative Code. This listing provides little or no habitat
protection beyond the State's development of a regional impact process,
which discloses impacts from projects, but provides only limited
regulatory protection for State-listed plants on private lands.
Florida Statutes 581.185 sections (3)(a) and (3)(b) prohibit any
person from willfully destroying or harvesting any species listed as
endangered or threatened on the Index, or growing such a plant on the
private land of another, or on any public land, without first obtaining
the written permission of the landowner and a permit from the Florida
Department of Plant Industry. The statute further provides that any
person willfully destroying or harvesting; transporting, carrying, or
conveying on any public road or highway; or selling or offering for
sale any plant listed in the Index as endangered must have a permit
from the State at all times when engaged in any such activities.
Further, Florida Statutes 581.185 section (10) provides for
consultation similar to section 7 of the Act for listed species, by
requiring the Department of Transportation to notify the Florida
Department of Agriculture and Consumer Services and the Endangered
Plant Advisory Council of planned highway construction at the time bids
are first advertised, to facilitate evaluation of the project for
listed plant populations, and to provide ``for the appropriate disposal
of such plants'' (i.e., transplanting).
However, this statute provides no substantive protection of habitat
or protection of potentially suitable habitat at this time. Florida
Statutes 581.185 section (8) waives State regulation for certain
classes of activities for all species on the Index, including the
clearing or removal of regulated plants for agricultural, forestry,
mining, construction (residential, commercial, or infrastructure), and
fire-control activities by a private landowner or his or her agent.
Local
In 1984, section 24-49 of the Code of Miami-Dade County established
regulation of County-designated NFCs. These regulations were placed on
specific properties throughout the County by an act of the Board of
County Commissioners in an effort to protect environmentally sensitive
forest lands. The Miami-Dade County RER has regulatory authority over
these County-designated NFCs and is charged with enforcing regulations
that provide partial protection of remaining upland forested areas
designated as NFC on the Miami Rock Ridge. NFC regulations are designed
to prevent clearing or destruction of native vegetation within
preserved areas. Miami-Dade County Code typically allows up to 20
percent of pine rocklands designated as NFC to be developed, and
requires that the remaining 80 percent be placed under a perpetual
covenant. The code requires that no more than 10 percent of a rockland
hammock designated as NFC may be developed for properties greater than
5 acres and that the remaining 90 percent be placed under a perpetual
covenant for preservation purposes (Joyner 2013a, 2014, pers. comm.;
Lima 2014, pers. comm.). However, for properties less than 5 acres, up
to one-half an acre may be cleared if the request is deemed a
reasonable use of property; this allowance often may be greater than 20
percent (for pine rocklands) or 10 percent (for rockland hammock) of
the property (Lima 2014, pers. comm.). NFC landowners are also required
to obtain an NFC permit for any work, including removal of nonnatives
within the boundaries of the NFC on their property. When RER discovers
unpermitted work, it takes appropriate enforcement action and seeks
restoration when possible. The NFC program is responsible for ensuring
that NFC permits are issued in accordance with the limitations and
requirements of the county code and that appropriate NFC preserves are
established and maintained in conjunction with the issuance of an NFC
permit when development occurs. The NFC program currently regulates
approximately 600 pine rocklands or pine rocklands/hammock properties,
comprising approximately 1,200 ha (3,000 ac) of habitat (Joyner 2013,
pers. comm.).
Although the NFC program is designed to protect rare and important
upland (non-wetlands) habitats in south Florida, the strategy has
limitations. For example, in certain circumstances where landowners can
demonstrate that limiting development to 20 percent (for pine
rocklands) or 10 percent (for rockland hammock) does not allow for
``reasonable use'' of the property, additional development may be
approved. Furthermore, Miami-Dade County Code provides for up to 100
percent of the NFC to be developed in limited circumstances for parcels
less than 2.02 ha (5 ac) in size and only requires coordination with
landowners if they plan to develop property or perform work within the
NFC-designated area. Therefore, many of the existing private forested
NFC parcels remain fragmented, without management obligations or
preserve designation, as development has not been proposed at a level
that would trigger the NFC regulatory requirements. Often, nonnative
vegetation over time begins to dominate and degrade the undeveloped and
unmanaged NFC landscape until it no longer meets the legal threshold of
an NFC, which applies only to land dominated by native vegetation. When
development of such degraded NFCs is proposed, Miami-Dade County Code
requires delisting of the degraded areas as part of the development
process. Property previously designated as NFC is removed from the list
even before development is initiated because of the abundance of
nonnative species, making it no longer considered to be jurisdictional
or subject to the NFC protection requirements of Miami-Dade County Code
(Grossenbacher 2013, pers. comm.).
Summary of Factor D
Currently, Chamaecrista lineata var. keyensis, Chamaesyce deltoidea
ssp. serpyllum, Linum arenicola, and Argythamnia blodgettii are found
on Federal, State, and county lands; however, there is no regulatory
mechanism in place that provides substantive protection of habitat or
protection of potentially suitable habitat at this time. NPS and
Service Refuge regulations provide protection at ENP and the Florida
Keys Wildlife Refuge Complex, respectively. The Act provides some
protection for candidate species on National Wildlife Refuges and
during intra-Service section 7 consultations. State regulations provide
protection against trade, but allow private landowners or their agents
to
[[Page 66855]]
clear or remove species on the Florida Regulated Plant Index. State
Park regulations provide protection for plants within Florida State
Parks. The NFC program in Miami is designed to protect rare and
important upland (non-wetlands) habitats in south Florida; however,
this regulatory strategy has several limitations (as described above)
that reduce its ability to protect the four plants and their habitats.
Although many populations of the four plants are afforded some
level of protection because they are on public conservation lands,
existing regulatory mechanisms have not led to a reduction or removal
of threats posed to these plants by a wide array of sources (see
discussions under Factor A, above, and Factor E, below).
Factor E. Other Natural or Manmade Factors Affecting Its Continued
Existence
Other natural or manmade factors affect Chamaecrista lineata var.
keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and
Argythamnia blodgettii to varying degrees. Specific threats to these
plants included in this factor consist of the spread of nonnative,
invasive plants; potentially incompatible management practices (such as
mowing and herbicide use); small population size and isolation; effects
of pesticide spraying on pollinators; climate change and sea level rise
(SLR); and risks from environmental stochasticity (extreme weather) on
these small populations. Each of these threats and its specific effect
on these plants is discussed in detail below.
Nonnative Plant Species
Nonnative, invasive plants compete with native plants for space,
light, water, and nutrients, and make habitat conditions unsuitable for
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii, which prefer
open conditions. Bradley and Gann (1999, pp. 13, 71-72) indicated that
the control of nonnative plants is one of the most important
conservation actions for these plants and a critical part of habitat
maintenance.
Nonnative plants have significantly affected pine rocklands, and
threaten all occurrences of these four species to some degree (Bradley
2006, pp. 25-26; Bradley and Gann 1999, pp. 18-19; Bradley and Saha
2009, p. 25; Bradley and van der Heiden 2013, pp. 12-16). As a result
of human activities, at least 277 taxa of nonnative plants have invaded
pine rocklands throughout south Florida (Service 1999, p. 3-175).
Neyraudia neyraudia (Burma reed) and Schinus terebinthifolius
(Brazilian pepper) threaten all four species (Bradley and Gann 1999,
pp. 13, 72). S. terebinthifolius, a nonnative tree, is the most
widespread and one of the most invasive species. It forms dense
thickets of tangled, woody stems that completely shade out and displace
native vegetation (Loflin 1991, p. 19; Langeland and Craddock Burks
1998, p. 54). Acacia auriculiformis (earleaf acacia), Rhynchelytrum
repens (natal grass), Lantana camara (shrub verbena), and Albizia
lebbeck (tongue tree) are some of the other nonnative species in pine
rocklands. More species of nonnative plants could become problems in
the future, such as Lygodium microphyllum (Old World climbing fern),
which is a serious threat throughout south Florida. Nonnative plants in
pine rocklands can also affect the characteristics of a fire when it
does occur. Historically, pine rocklands had an open, low understory
where natural fires remained patchy with low temperature intensity,
thus sparing many native plants such as Chamaecrista lineata var.
keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and
Argythamnia blodgettii. Dense infestations of Neyraudia neyraudia and
Schinus terebinthifolius cause higher fire temperatures and longer
burning periods. With the presence of invasive, nonnative species, it
is uncertain how fire, even under a managed situation, will affect
these plants.
At least 162 nonnative plant species are known to invade rockland
hammocks; impacts are particularly severe on the Miami Rock Ridge
(Service 1999, pp. 3-135). Nonnative plant species have significantly
affected rockland hammocks where Argythamnia blodgettii occurs and are
considered one of the threats to the species (Snyder et al. 1990, p.
273; Hodges and Bradley 2006, p. 14). In many Miami-Dade County parks,
nonnative plant species comprise 50 percent of the flora in hammock
fragments (Service 1999, pp. 3-135). Horvitz (et al. 1998, p. 968)
suggests the displacement of native species by nonnative species in
conservation and preserve areas is a complex problem with serious
impacts to biodiversity conservation, as management in these areas
generally does not protect native species and ecological processes, as
intended. Problematic nonnative, invasive plants associated with
rockland hammocks include Leucaena leucocephala (lead tree), Schinus
terebinthifolius, Bischofia javanica (bishop wood), Syngonium
podophyllum (American evergreen), Jasminum fluminense (Brazilian
jasmine), Rubus niveus (mysore raspberry), Nephrolepis brownii (Asian
swordfern), Schefflera actinophylla (octopus tree), Jasminum dichotomum
(Gold Coast jasmine), Epipremnum pinnatum (centipede tongavine), and
Nephrolepis cordifolia (narrow swordfern) (Possley 2013h-i, pers.
comm.).
Management of nonnative, invasive plants in pine rocklands and
rockland hammocks in Miami-Dade County is further complicated because
the vast majority of pine rocklands and rockland hammocks are small,
fragmented areas bordered by urban development. In the Florida Keys,
larger fragments are interspersed with development. Developed or
unmanaged areas that contain nonnative species can act as a seed source
for nonnatives, allowing them to continue to invade managed pine
rocklands or rockland hammocks (Bradley and Gann 1999, p. 13).
Nonnative plant species are also a concern on private lands, where
often these species are not controlled due to associated costs, lack of
interest, or lack of knowledge of detrimental impacts to the ecosystem.
Undiscovered populations of the four plants on private lands could
certainly be at risk. Overall, active management is necessary to
control for nonnative species and to protect unique and rare habitats
where the four plants occur (Snyder et al. 1990, p. 273).
Management of Roadsides and Disturbed Areas
All four plants occur in disturbed areas such as roadsides and
areas that formerly were pine rocklands. Linum arenicola is
particularly vulnerable to management practices in these areas because
nearly all populations of the species are currently found on disturbed
sites. The large L. arenicola population at HARB and SOCSOUTH is
located largely in areas that are regularly mowed. Similarly, the small
population of L. arenicola at the Everglades Archery Range, which is
owned by Miami-Dade County and managed as a part of Camp Owaissa Bauer,
is growing along the edges of the unimproved perimeter road that is
regularly mowed. Finally, the two populations of L. arenicola on canal
banks are subject to mowing, herbicide treatments, and revegetation
efforts (sodding) (Bradley and van der Heiden 2013, pp. 8-10). The
population of Argythamnia blodgettii at Lignumvitae Key Botanical State
Park grows around the perimeter of the large lawn around the residence.
Maintenance activities
[[Page 66856]]
and encroachment of exotic lawn grasses are potential threats to this
population (Hodges and Bradley 2006, p. 14). At Windley Key State Park,
A. blodgettii grows in two quarry bottoms. In the first, larger quarry,
to the east of the visitor center, plants apparently persist only in
natural areas not being mowed. However, the majority of the plants are
in the farthest quarry, which is not mowed (Hodges and Bradley 2006, p.
15).
While no studies have investigated the effect of mowing on the four
plants, research has been conducted on the federally endangered Linum
carteri var. carteri (Carter's small-flowered flax, a close relative of
Linum arenicola that also occurs in pine rocklands and disturbed
sites). The study found significantly higher densities of plants at the
mown sites where competition with other plants is decreased (Maschinski
and Walters 2007, p. 56). However, plants growing on mown sites were
shorter, which may affect fruiting magnitude. While mowing did not
usually kill adult plants, if mowing occurred prior to plants reaching
reproductive status, it could delay reproduction (Maschinski and
Walters 2007, pp. 56-57). If such mowing occurs repeatedly,
reproduction of those plants would be entirely eliminated. If, instead,
mowing occurs at least 3 weeks after flowering, there would be a higher
probability of adults setting fruit prior to mowing; mowing may then
act as a positive disturbance by both scattering seeds and reducing
competition (Maschinski and Walters 2007, p. 57). The exact impacts of
mowing thus depend on the timing of the mowing event, rainfall prior to
and following mowing, and the numbers of plants in the population that
have reached a reproductive state.
Herbicide applications, the installation of sod, and dumping may
affect populations of the four plants that occur on roadsides, canals
banks, and other disturbed sites. Signs of herbicide application were
noted at the site of the Big Torch Key roadside population of Linum
arenicola in 2010 (Hodges 2010, p. 2). At the L-31 E canal site, plants
of L. arenicola were lost on the levee close to Card Sound Road due to
the installation of Bahia grass (Paspalum conjugatum) sod in recent
years, an activity associated with the installation of new culverts. If
similar projects are planned, other erosion control measures should be
investigated that do not pose a threat to L. arenicola (Bradley and Van
Der Heiden 2013, p. 10). Illegal dumping of storm-generated trash after
Hurricane Wilma had a large impact on roadside populations of plants in
the lower Florida Keys (Hodges and Bradley 2006, pp. 11-12, 19, 39).
All populations of the four plants that occur on disturbed sites
are vulnerable to regular maintenance activities such as mowing and
herbicide applications, and dumping. This includes portions of all
populations of Chamaecrista lineata var. keyensis and Chamaesyce
deltoidea ssp. serpyllum, 10 of 12 Linum arenicola populations, and 5
of 34 Argythamnia blodgettii populations. All roadside populations are
also vulnerable to infrastructure projects such as road widening and
installation of underground cable, sewer, and water lines.
Pesticide Effects on Pollinators
Another potential anthropogenic threat to the four plants is
current application of insecticides throughout these plants' ranges to
control mosquito populations. Currently, an aerial insecticide (1,2-
dibromo-2,2-dichloroethyl dimethyl phosphate) and ground insecticide
(Permethrin) are applied during the May through November timeframe in
many parts of south Florida. Nontarget effects of mosquito control may
include the loss of pollinating insects upon which certain plants
depend.
Koptur and Liu (2003, p. 1184) reported a decrease in Chamaecrista
lineata var. keyensis pollinator activity following mosquito spraying
on Big Pine Key. Mosquito spraying remains a factor on Big Pine Key,
and its suppression of pollinator populations may have a long-term
impact on reproduction rates. Extensive studies in the Florida Keys
suggest that broad spectrum insecticides negatively affect nontarget
invertebrates, including pollinators (Hennessey 1991; Eliazar and Emmel
1991; Kevan et al. 1997; Salvato 2001; Bargar 2011; Hoang et al. 2011).
In addition, pesticides have been shown to drift into adjacent
undisturbed habitat that serves as a refuge for native biota (Hennessey
1992; Pierce et al. 2005; Zhong et al. 2010; Bargar 2011). These
pesticides can be fatal to nontarget invertebrates that move between
urban and forest habitats, altering ecological processes within forest
communities (Kevan and Plowright 1989, 1995; Liu and Koptur 2003).
Pesticide spraying practices by the Monroe County Mosquito Control
District within NKDR have changed to reduce pesticide use and limit
insecticide drift into pine rocklands habitat as a result of agreements
between the Service and Florida Keys Mosquito Control District (FKMCD)
after critical habitat was designated in 2014 for the Florida leafwing
(Anaea troglodyta floridalis) and Bartram's scrub-hairstreak (Strymon
acis bartrami) butterflies (79 FR 47180; August 12, 2014). This
designation includes all pine rockland within NKDR where its sole
larval host, Croton linearis, can potentially occur.
Since 2003, expanded larvicide treatments to surrounding islands
have significantly reduced adulticide use on Big Pine Key, No Name Key,
and the Torch Keys. In addition, the number of aerially applied Naled
treatments allowed on NKDR has been limited since 2008 (Florida Key
Mosquito Control District 2012, pp. 10-11). Designated ``No spray
zones'' that include the core habitat used by pine rockland butterflies
and several linear miles of pine rocklands habitat within the Refuge-
neighborhood interface are now excluded from truck spray applications
(Anderson 2012, pers. comm.; Service 2012, p. 32). These exclusions and
buffer zones encompass over 95 percent of extant croton distribution on
Big Pine Key, and include the majority of known recent and historical
Florida leafwing population centers on the island (Salvato 2012, pers.
comm.). The area largely coincides with the range of these four plants
in the lower Florida Keys. Therefore, the effects of mosquito control
pesticide application on the pollinators of the four plants have been
minimized at NKDR.
In summary, critical habitat regulations for Bartram's scrub-
hairstreak butterfly and Florida leafwing have extended benefits to
populations of these four plants and their pollinator guild by limiting
mosquito insecticide activity in pine rocklands habitat in the Florida
Keys. Nevertheless, we are proceeding cautiously and have initiated a
multi-year research project to further investigate the level of impact
pesticides have on these four plants and their pollinators throughout
their ranges.
Environmental Stochasticity
Endemic species whose populations exhibit a high degree of
isolation and narrow geographic distribution, such as Chamaecrista
lineata var. keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum
arenicola, and Argythamnia blodgettii, are extremely susceptible to
extinction from both random and nonrandom catastrophic natural or
human-caused events. Of the four species, Argythamnia blodgettii is
probably less vulnerable because of the larger number of sites where it
occurs throughout Miami-Dade and Monroe Counties. Small populations of
species,
[[Page 66857]]
without positive growth rates, are considered to have a high extinction
risk from site-specific demographic and environmental stochasticity
(Lande 1993, pp. 911-927).
The climate of south Florida is driven by a combination of local,
regional, and global weather events and oscillations. There are three
main ``seasons'': (1) The wet season, which is hot, rainy, and humid
from June through October; (2) the official hurricane season that
extends one month beyond the wet season (June 1 through November 30),
with peak season being August and September; and (3) the dry season,
which is drier and cooler, from November through May. In the dry
season, periodic surges of cool and dry continental air masses
influence the weather with short-duration rain events followed by long
periods of dry weather.
Florida is considered the most vulnerable State in the United
States to hurricanes and tropical storms (Florida Climate Center,
http://coaps.fsu.edu/climate_center). Based on data gathered from 1856
to 2008, Klotzbach and Gray (2009, p. 28) calculated the climatological
probabilities for each State being impacted by a hurricane or major
hurricane in all years over the 152-year timespan. Of the coastal
States analyzed, Florida had the highest climatological probabilities,
with a 51 percent probability of a hurricane (Category 1 or 2) and a 21
percent probability of a major hurricane (Category 3 or higher). From
1856 to 2008, Florida experienced 109 hurricanes, 36 of which were
considered major hurricanes. Given the few isolated populations and
restricted range of the four plants in locations prone to storm
influences (i.e., Miami-Dade and Monroe Counties), they are at
substantial risk from hurricanes, storm surges, and other extreme
weather events.
Hurricanes, storm surge, and extreme high tide events are natural
events that can pose a threat to the four plants. Hurricanes and
tropical storms can modify habitat (e.g., through storm surge) and have
the potential to destroy entire populations. Climate change may lead to
increased frequency and duration of severe storms (Golladay et al.
2004, p. 504; McLaughlin et al. 2002, p. 6074; Cook et al. 2004, p.
1015). The four plants experienced these disturbances historically, but
had the benefit of more abundant and contiguous habitat to buffer them
from extirpations. With most of the historical habitat having been
destroyed or modified, the few remaining populations of these plants
could face local extirpations due to stochastic events.
The Florida Keys were impacted by three hurricanes in 2005: Katrina
on August 26, Rita on September 20, and Wilma on October 24. Hurricane
Wilma had the largest impact, with storm surges flooding much of the
landmass of the Keys. In some places, this water impounded and sat for
days. The vegetation in many areas was top-killed due to salt water
inundation (Hodges and Bradley 2006, p. 9). Flooding kills plants that
do not have adaptations to tolerate anoxic soil conditions that persist
after flooding; the flooding and resulting high salinities might also
impact soil seed banks of the four plants (Bradley and Saha 2009, pp.
27-28). After hurricane Wilma, the herb layer in pine rocklands in
close proximity to the coast was brown with few plants having live
material above ground (Bradley 2006, p. 11). Subsequent surveys found
no Linum arenicola and little Chamaecrista lineata var. keyensis or
Chamaesyce deltoidea ssp. serpyllum in areas where they previously
occurred. Not only did the storm surge kill the vegetation, but many of
the roadside areas were heavily disturbed by dumping and removal of
storm debris (Bradley 2006, p. 37). Estimates of the population sizes
pre- and post-Wilma were calculated for Chamaesyce deltoidea ssp.
serpyllum and Chamaecrista lineata var. keyensis. Each declined in the
months following the storm, by 41.2 percent and 48.0 percent,
respectively (Bradley and Saha 2009, p. 2). L. arenicola was not found
at all in surveys 8 to 9 weeks after the hurricane (Bradley 2006, p.
36). The Middle Torch Key population was extirpated after Hurricane
Wilma, and the population on Big Torch Key declined drastically, with
only one individual located. Both of these areas were heavily affected
by storm surges during Hurricane Wilma (Hodges 2010, p. 2). As of 2013,
populations of Chamaecrista lineata var. keyensis, Chamaesyce deltoidea
ssp. serpyllum, and L. arenicola in the Florida Keys have not returned
to pre-Hurricane Wilma levels (Bradley et al. 2015, pp. 21, 25, 29).
Some climate change models predict increased frequency and duration
of severe storms, including hurricanes and tropical storms (McLaughlin
et al. 2002, p. 6074; Cook et al. 2004, p. 1015; Golladay et al. 2004,
p. 504). Other models predict hurricane and tropical storm frequencies
in the Atlantic are expected to decrease between 10 and 30 percent by
2100 (Knutson et al. 2008, pp. 1-21). For those models that predict
fewer hurricanes, predictions of hurricane wind speeds are expected to
increase by 5 to 10 percent due to an increase in available energy for
intense storms. Increases in hurricane winds can elevate the chances of
damage to existing canopy and increase storm surge heights.
All populations of the four plants are vulnerable to hurricane wind
damage. Populations close to the coast and all populations of the four
plants in the Florida Keys are vulnerable to inundation by storm surge.
Historically, the four plant species may have benefitted from more
abundant and contiguous habitat to buffer them from storm events. The
small size of many populations of these plants makes them especially
vulnerable, in which the loss of even a few individuals could reduce
the viability of a single population. The destruction and modification
of native habitat, combined with small population size, has likely
contributed over time to the stress, decline, and, in some instances,
extirpation of populations or local occurrences due to stochastic
events.
Due to the small size of some existing populations of Chamaecrista
lineata var. keyensis, Linum arenicola, and Argythamnia blodgettii (see
below) and the narrow geographic range of all four plant species, their
overall resilience to these factors is likely low. These factors,
combined with additional stress from habitat loss and modification
(e.g., inadequate fire management) may increase the inherent risk of
stochastic events that impact these plants. For these reasons, all four
plants are at risk of extirpation during extreme stochastic events. Of
the four species, Argythamnia blodgettii is probably less vulnerable
because of the larger number of sites where it occurs throughout Miami-
Dade and Monroe Counties.
Small Population Size and Isolation
Endemic species whose populations exhibit a high degree of
isolation are extremely susceptible to extinction from both random and
nonrandom catastrophic natural or human-caused events. Species that are
restricted to geographically limited areas are inherently more
vulnerable to extinction than widespread species because of the
increased risk of genetic bottlenecks, random demographic fluctuations,
climate change, and localized catastrophes such as hurricanes and
disease outbreaks (Mangel and Tier 1994, p. 607; Pimm et al. 1998, p.
757). These problems are further magnified when populations are few and
restricted to a very small geographic area, and when the number of
individuals is very small. Populations with these
[[Page 66858]]
characteristics face an increased likelihood of stochastic extinction
due to changes in demography, the environment, genetics, or other
factors (Gilpin and Soule 1986, pp. 24-34). Small, isolated populations
often exhibit reduced levels of genetic variability, which diminishes
the species' capacity to adapt and respond to environmental changes,
thereby decreasing the probability of long-term persistence (e.g.,
Barrett and Kohn 1991, p. 4; Newman and Pilson 1997, p. 361). Very
small plant populations may experience reduced reproductive vigor due
to ineffective pollination or inbreeding depression. Isolated
individuals have difficulty achieving natural pollen exchange, which
limits the production of viable seed. The problems associated with
small population size and vulnerability to random demographic
fluctuations or natural catastrophes are further magnified by
synergistic interactions with other threats, such as those discussed
above (see Factors A and C).
Chamaecrista lineata var. keyensis and Chamaesyce deltoidea ssp.
serpyllum both have large populations on Big Pine Key. The other extant
occurrence of Chamaecrista lineata var. keyensis in the Florida Keys,
on Cudjoe Key, is small. Five out of 12 extant Linum arenicola
populations, and 20 of 34 Argythamnia blodgettii populations, have
fewer than 100 individuals. These small populations are at risk of
adverse effects from reduced genetic variation, an increased risk of
inbreeding depression, and reduced reproductive output. Many of these
populations are small and isolated from each other, decreasing the
likelihood that they could be naturally reestablished in the event that
extinction from one location would occur. Argythamnia blodgettii is the
only one of the four plants species that occurs in ENP, where a
population of over 2,000 plants is stable and prescribed fire and other
management activities that benefit A. blodgettii are conducted on a
regular basis.
Climate Change and Sea Level Rise
Climatic changes, including sea level rise (SLR), are occurring in
the State of Florida and are impacting associated plants, animals, and
habitats. Our analyses under the Act include consideration of ongoing
and projected changes in climate. The term ``climate,'' as defined by
the Intergovernmental Panel on Climate Change (IPCC), refers to the
mean and variability of different types of weather conditions over
time, with 30 years being a typical period for such measurements,
although shorter or longer periods also may be used (IPCC 2013, p.
1450). The term ``climate change'' thus refers to a change in the mean
or variability of one or more measures of climate (e.g., temperature or
precipitation) that persists for an extended period, typically decades
or longer, whether the change is due to natural variability, human
activity, or both (IPCC 2013, p. 1450). A recent compilation of climate
change and its effects is available from IPCC reports (IPCC 2013,
entire).
Scientific measurements spanning several decades demonstrate that
changes in climate are occurring, and that the rate of change has been
faster since the 1950s. Examples include warming of the global climate
system, and substantial increases in precipitation in some regions of
the world and decreases in other regions. (For these and other
examples, see IPCC 2007a, p. 30; Solomon et al. 2007, pp. 35-54, 82-
85). Results of scientific analyses presented by the IPCC show that
most of the observed increase in global average temperature since the
mid-20th century cannot be explained by natural variability in climate,
and is ``very likely'' (defined by the IPCC as 90 percent or higher
probability) due to the observed increase in greenhouse gas (GHG)
concentrations in the atmosphere as a result of human activities,
particularly carbon dioxide emissions from use of fossil fuels (IPCC
2007a, pp. 5-6 and figures SPM.3 and SPM.4; Solomon et al. 2007, pp.
21-35). Further confirmation of the role of GHGs comes from analyses by
Huber and Knutti (2011, p. 4), who concluded it is extremely likely
that approximately 75 percent of global warming since 1950 has been
caused by human activities.
Scientists use a variety of climate models, which include
consideration of natural processes and variability, as well as various
scenarios of potential levels and timing of GHG emissions, to evaluate
the causes of changes already observed and to project future changes in
temperature and other climate conditions (e.g., Meehl et al. 2007,
entire; Ganguly et al. 2009, pp. 11555, 15558; Prinn et al. 2011, pp.
527, 529). All combinations of models and emissions scenarios yield
very similar projections of increases in the most common measure of
climate change, average global surface temperature (commonly known as
global warming), until about 2030. Although projections of the
magnitude and rate of warming differ after about 2030, the overall
trajectory of all the projections is one of increased global warming
through the end of this century, even for the projections based on
scenarios that assume that GHG emissions will stabilize or decline.
Thus, there is strong scientific support for projections that warming
will continue through the 21st century, and that the magnitude and rate
of change will be influenced substantially by the extent of GHG
emissions (IPCC 2007a, pp. 44-45; Meehl et al. 2007, pp. 760-764, 797-
811; Ganguly et al. 2009, pp. 15555-15558; Prinn et al. 2011, pp. 527,
529). (See IPCC 2007b, p. 8, for a summary of other global projections
of climate-related changes, such as frequency of heat waves and changes
in precipitation. Also see IPCC 2011 (entire) for a summary of
observations and projections of extreme climate events.)
Various changes in climate may have direct or indirect effects on
species. These effects may be positive, neutral, or negative, and they
may change over time, depending on the species and other relevant
considerations, such as interactions of climate with other variables
(e.g., habitat fragmentation) (IPCC 2007, pp. 8-14, 18-19). Identifying
likely effects often involves aspects of climate change vulnerability
analysis. Vulnerability refers to the degree to which a species (or
system) is susceptible to, and unable to cope with, adverse effects of
climate change, including climate variability and extremes.
Vulnerability is a function of the type, magnitude, and rate of climate
change and variation to which a species is exposed, its sensitivity,
and its adaptive capacity (IPCC 2007a, p. 89; see also Glick et al.
2011, pp. 19-22). There is no single method for conducting such
analyses that applies to all situations (Glick et al. 2011, p. 3). We
use our expert judgment and appropriate analytical approaches to weigh
relevant information, including uncertainty, in our consideration of
various aspects of climate change.
As is the case with all stressors that we assess, even if we
conclude that a species is currently affected or is likely to be
affected in a negative way by one or more climate-related impacts, it
does not necessarily follow that the species meets the definition of an
``endangered species'' or a ``threatened species'' under the Act. If a
species is listed as endangered or threatened, knowledge regarding the
vulnerability of the species to, and known or anticipated impacts from,
climate-associated changes in environmental conditions can be used to
help devise appropriate strategies for its recovery.
Global climate projections are informative, and, in some cases, the
only or the best scientific information available for us to use.
However, projected changes in climate and related
[[Page 66859]]
impacts can vary substantially across and within different regions of
the world (e.g., IPCC 2007a, pp. 8-12). Therefore, we use
``downscaled'' projections when they are available and have been
developed through appropriate scientific procedures, because such
projections provide higher resolution information that is more relevant
to spatial scales used for analyses of a given species (see Glick et
al. 2011, pp. 58-61, for a discussion of downscaling).
With regard to our analysis for Chamaecrista lineata var. keyensis,
Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia
blodgettii, downscaled projections suggest that SLR is the largest
climate-driven challenge to low-lying coastal areas in the subtropical
ecoregion of southern Florida (U.S. Climate Change Science Program
(USCCSP) 2008, pp. 5-31, 5-32). All populations of the four plants
occur at elevations from 2.83-4.14 meters (m) (9.29-13.57 feet (ft))
above sea level, making these plants highly susceptible to increased
storm surges and related impacts associated with SLR.
We acknowledge that the drivers of SLR (especially contributions of
melting glaciers) are not completely understood, and there is
uncertainty with regard to the rate and amount of SLR. This uncertainty
increases as projections are made further into the future. For this
reason, we examine threats to the species within the range of
projections found in recent climate change literature.
The long-term record at Key West shows that sea level rose on
average 0.229 cm (0.090 in) annually between 1913 and 2013 (National
Oceanographic and Atmospheric Administration (NOAA) 2013, p. 1). This
equates to approximately 22.9 cm (9.02 in) over the last 100 years.
IPCC (2008, p. 28) emphasized it is very likely that the average rate
of SLR during the 21st century will exceed the historical rate. The
IPCC Special Report on Emission Scenarios (2000, entire) presented a
range of scenarios based on the computed amount of change in the
climate system due to various potential amounts of anthropogenic
greenhouse gases and aerosols in 2100. Each scenario describes a future
world with varying levels of atmospheric pollution leading to
corresponding levels of global warming and corresponding levels of SLR.
The IPCC Synthesis Report (2007, entire) provided an integrated view of
climate change and presented updated projections of future climate
change and related impacts under different scenarios.
Subsequent to the 2007 IPCC Report, the scientific community has
continued to model SLR. Recent peer-reviewed publications indicate a
movement toward increased acceleration of SLR. Observed SLR rates are
already trending along the higher end of the 2007 IPCC estimates, and
it is now widely held that SLR will exceed the levels projected by the
IPCC (Rahmstorf et al. 2012, p. 1; Grinsted et al. 2010, p. 470). Taken
together, these studies support the use of higher end estimates now
prevalent in the scientific literature. Recent studies have estimated
global mean SLR of 1.0-2.0 m (3.3-6.6 ft) by 2100 as follows: 0.75-1.90
m (2.50-6.20 ft; Vermeer and Rahmstorf 2009, p. 21530); 0.8-2.0 m (2.6-
6.6 ft; Pfeffer et al. 2008, p. 1342); 0.9-1.3 m (3.0-4.3 ft; Grinsted
et al. 2010, pp. 469-470); 0.6-1.6 m (2.0-5.2 ft; Jevrejeva et al.
2010, p. 4); and 0.5-1.4 m (1.6-4.6 ft; National Research Council 2012,
p. 2).
Other processes expected to be affected by projected warming
include temperatures, rainfall (amount, seasonal timing, and
distribution), and storms (frequency and intensity) (see
``Environmental Stochasticity'', above). Models where sea surface
temperatures are increasing also show a higher probability of more
intense storms (Maschinski et al. 2011, p. 148). The Massachusetts
Institute of Technology (MIT) modeled several scenarios combining
various levels of SLR, temperature change, and precipitation
differences with human population growth, policy assumptions, and
conservation funding changes. All of the scenarios, from small climate
change shifts to major changes, indicate significant effects on coastal
Miami-Dade County. The Science and Technology Committee of the Miami-
Dade County Climate Change Task Force (Wanless et al. 2008, p. 1)
recognize that significant SLR is a serious concern for Miami-Dade
County in the near future. In a January 2008 statement, the committee
warned that sea level is expected to rise at least 0.9-1.5 m (3.0-5.0
ft) within this century (Wanless et al. 2008, p. 3). With a 0.9-1.2 m
(3.0-4.0 ft) rise in sea level (above baseline) in Miami-Dade County,
spring high tides would be at about 1.83-2.13 m (6.0-7.0 ft);
freshwater resources would be gone; the Everglades would be inundated
on the west side of Miami-Dade County; the barrier islands would be
largely inundated; storm surges would be devastating to coastal habitat
and associated species; and landfill sites would be exposed to erosion,
contaminating marine and coastal environments. Freshwater and coastal
mangrove wetlands will be unable to keep up with or offset SLR of 0.61
m (2.0 ft) per century or greater. With a 1.52 m (5.0 ft) rise, Miami-
Dade County will be extremely diminished (Wanless et al. 2008, pp. 3-
4).
SLR projections from various scenarios have been downscaled by TNC
(2011, entire) and Zhang et al. (2011, entire) for the Florida Keys.
Using the IPCC best-case, low-pollution scenario, a rise of 18 cm (7
in) (a rate close to the historical average reported above) would
result in the inundation of 23,796 ha (58,800 acres) or 38.2 percent of
the Florida Keys upland area by the year 2100 (TNC 2011, p. 25). Under
the IPCC worst-case, high-pollution scenario, a rise of 59 cm (23.2 in)
would result in the inundation of 46,539 ha (115,000 acres) or 74.7
percent of the Florida Keys upland area by the year 2100 (TNC 2011, p.
25). Using Rahmstorf et al.'s (2007; p. 368) SLR projections of 100 to
140 cm, 80.5 to 92.2 percent of the Florida Keys land area would be
inundated by 2100. The Zhang et al. (2011, p. 136) study models SLR up
to 1.8 m (5.9 ft) for the Florida Keys, which would inundate 93.6
percent of the current land area of the Keys.
Prior to inundations from SLR, there will likely be habitat
transitions related to climate change, including changes to hydrology
and increasing vulnerability to storm surge. Hydrology has a strong
influence on plant distribution in coastal areas (IPCC 2008, p. 57).
Such communities typically grade from salt to brackish to freshwater
species. From the 1930s to 1950s, increased salinity contributed to the
decline of cabbage palm forests in southwest Florida (Williams et al.
1999, pp. 2056-2059), expansion of mangroves into adjacent marshes in
the Everglades (Ross et al. 2000, pp. 101, 111), and loss of pine
rocklands in the Keys (Ross et al. 1994, pp. 144, 151-155). In Florida,
pine rocklands transition into rockland hammocks, and, as such, these
habitat types are closely associated in the landscape. A study
conducted in one pine rocklands location on Sugar Loaf Key (with an
average elevation of 0.89 m (2.90 ft)) found an approximately 65
percent reduction in an area occupied by South Florida slash pine over
a 70-year period, with pine mortality and subsequent increased
proportions of halophytic (salt-loving) plants occurring earlier at the
lower elevations (Ross et al. 1994, pp. 149-152). During this same time
span, local sea level had risen by 15 cm (6 in), and Ross et al. (1994,
p. 152) found evidence of groundwater and soil water salinization.
Extrapolating this situation to hardwood hammocks is
[[Page 66860]]
not straightforward, but it suggests that changes in rockland hammock
species composition may not be an issue in the immediate future (5-10
years); however, over the long term (within the next 10-50 years), it
may be an issue if current projections of SLR occur and freshwater
inputs are not sufficient to maintain high humidities and prevent
changes in existing canopy species through salinization (Saha et al.
2011, pp. 22-25). Ross et al. (2009, pp. 471-478) suggested that
interactions between SLR and pulse disturbances (e.g., storm surges)
can cause vegetation to change sooner than projected based on sea level
alone.
Impacts from climate change including regional SLR have been
studied for coastal hammocks but not rockland hammock habitat. Saha (et
al. 2011, pp. 24-25) conducted a risk assessment on rare plant species
in ENP and found that impacts from SLR have significant effects on
imperiled taxa. This study also predicted a decline in the extent of
coastal hammocks with initial SLR, coupled with a reduction in
freshwater recharge volume and an increase in pore water (water filling
spaces between grains of sediment) salinity, which will push hardwood
species to the edge of their drought (freshwater shortage and
physiological) tolerance, jeopardizing critically imperiled or endemic
species, or both, with possible extirpation. In south Florida, SLR of
1-2 m (3.3-6.6 ft) is estimated by 2100, which is on the higher end of
global estimates for SLR. These projected increases in sea level pose a
threat to coastal plant communities and habitats from mangroves at sea
level to salinity-intolerant, coastal rockland hammocks where
elevations are generally less than 2.0 m (6.1 ft) above sea level (Saha
et al. 2011, p. 2). Loss or degradation of these habitats can be a
direct result of SLR or in combination of several other factors,
including diversion of freshwater flow, hurricanes, and exotic plant
species infestations, which can ultimately pose a threat to rare plant
populations (Saha et al. 2011, p. 24).
Habitats for these species are restricted to relatively immobile
geologic features separated by large expanses of flooded, inhospitable
wetland or ocean, leading us to conclude that these habitats will
likely not be able to migrate as sea level rises (Saha et al. 2011, pp.
103-104). Because of the extreme fragmentation of remaining habitat and
isolation of remaining populations, and the accelerating rate at which
SLR is projected to occur (Grinsted et al. 2010, p. 470), it will be
particularly difficult for these species to disperse to suitable
habitat once existing sites that support them are lost to SLR. Patterns
of development will also likely be significant factors influencing
whether natural communities can move and persist (IPCC 2008, p. 57;
CCSP 2008, pp. 7-6). The plant species face significant risks from
coastal squeeze that occurs when habitat is pressed between rising sea
levels and coastal development that prevents landward migration of
species. The ultimate effect of these impacts is likely to result in
reductions in reproduction and survival, with corresponding decreases
in population numbers.
Saha (et al. 2011, p. 4) suggested that the rising water table
accompanying SLR will shrink the vadose zone (the area which extends
from the top of the ground surface to the water table); increase
salinity in the bottom portion of the freshwater lens, thereby
increasing brackishness of plant-available water; and influence tree
species composition of coastal hardwood hammocks based upon species-
level tolerance to salinity or drought or both. Evidence of population
declines and shifts in rare plant communities, along with multi-trophic
effects, already have been documented on the low-elevation islands of
the Florida Keys (Maschinski et al. 2011, p. 148).
Direct losses to extant populations of all four plants are expected
due to habitat loss and modification from SLR by 2100. We analyzed
existing sites that support populations of the four plants using the
National Oceanic and Atmospheric Administration (NOAA) Sea Level Rise
and Coastal Impacts viewer. Below, we discuss general implications of
sea level rise within the range of projections discussed above on the
current distribution of these species. The NOAA tool uses 1-foot
increments, so the analysis is based on 0.91 m (3 ft) and 1.8 m (6 ft).
Chamaecrista lineata var. keyensis: A 0.91-m (3-ft) rise would
inundate most areas of Big Pine Key, and all areas of Cudjoe Key, that
support Chamaecrista lineata var. keyensis, and reduce both Keys to
several much smaller islands. The remaining uplands on these islands
would likely transition to buttonwoods and saltmarshes, and would be
extremely vulnerable to storm surge. This will further reduce and
fragment these populations. A 1.8-m (6-ft) rise would completely
inundate all areas that support C. lineata var. keyensis and eliminate
all pine rocklands habitat within the historic range of the species.
Chamaesyce deltoidea var. serpyllum: A 0.91-m (3-ft) rise would
inundate most areas of Big Pine Key that support Chamaesyce deltoidea
var. serpyllum, and reduce the Key to three to five much smaller
islands. The remaining uplands would likely transition to buttonwoods
and saltmarshes, and would be extremely vulnerable to storm surge. This
will further reduce and fragment the population. A 1.8-m (6-ft) rise
would completely inundate all areas that support C. deltoidea var.
serpyllum and eliminate all pine rocklands habitat within the historic
range of the species.
Linum arenicola: In Miami-Dade County, a 0.91-m (3-ft) rise would
inundate the area that supports a large extant population of Linum
arenicola along L-31E canal. While other areas that support the species
are located in higher elevation areas along the coastal ridge, changes
in the salinity of the water table and soils, along with additional
vegetation shifts in the region, are likely. Remaining uplands may
transition to wetter, more salt-tolerant plant communities. This will
further reduce and fragment the populations. A 1.8-m (6-ft) rise would
inundate portions of the largest known population (HARB), as well the
population along L-31E canal. The areas that support Linum arenicola at
the Richmond pinelands to the north would not be inundated, but pine
rocklands in these areas may be reduced through transition to wetter,
more salt-tolerant plant communities, as discussed above.
In the Florida Keys, a 0.91-m (3-ft) rise would inundate most areas
of Big Pine Key and Lower Sugarloaf Key, and all of the areas on Upper
Sugarloaf Key and Big Torch Key, that support Linum arenicola, and
reduce these Keys to numerous much smaller islands. The remaining
uplands on these small islands would likely transition to buttonwoods
and saltmarshes, and would be extremely vulnerable to further losses
due to storm surge. This would further reduce and fragment the
populations. A 1.8-m (6-ft) rise would completely inundate all areas
that support Linum arenicola in the Florida Keys and eliminate all pine
rocklands habitat within the historic range of the species in Monroe
County.
Argythamnia blodgettii: In Miami-Dade County, a 0.91-m (3-ft) rise
would not inundate any extant populations of Argythamnia blodgettii
because these habitats are located in higher elevation areas along the
coastal ridge. However, changes in the salinity of the water table and
soils, along with additional vegetation shifts in the region, are
likely. Remaining uplands may likely transition to wetter, more salt-
tolerant plant communities. This will further
[[Page 66861]]
reduce and fragment the populations. A 1.8-m (6-ft) rise would inundate
portions of Crandon Park, making it unsuitable for A. blodgettii. Other
areas that support A. blodgettii, including the Richmond pinelands to
the north, and Long Pine Key in ENP, would not be inundated, but
habitats in these areas may be reduced through transition to wetter,
more salt-tolerant plant communities, as discussed above.
In the Florida Keys, a 0.91-m (3-ft) rise would reduce the area of
islands in the upper Keys, but extant populations on Key Largo, Windley
Key, and Lignumvitae Key are less vulnerable than the Middle and Lower
Keys, which are at lower elevations. Lower Matecumbe Key, Plantation
Key, Vaca Key, Big Pine Key, and Big Munson Island would be fragmented
and reduced to numerous much smaller islands. The remaining uplands on
these small islands would likely transition to buttonwoods and
saltmarshes, and would be extremely vulnerable further losses to storm
surge. This would further reduce and fragment the populations. A 1.8-m
(6-ft) rise would completely inundate all areas that support
Argythamnia blodgettii south of Lignumvitae Key. Key Largo, Windley
Key, and Lignumvitae Key are the only existing areas supporting extant
populations that could continue to support a population given a 1.8-m
(6-ft) sea level rise.
Conservation Efforts To Reduce Other Natural or Manmade Factors
Affecting Its Continued Existence
NPS, the Service, Miami-Dade County, and the State of Florida have
ongoing nonnative plant management programs to reduce threats on public
lands, as funding and resources allow. In Miami-Dade County, nonnative,
invasive plant management is very active, with a goal to treat all
publicly owned properties at least once a year and more often in many
cases. IRC and FTBG conduct research and monitoring in various natural
areas within Miami-Dade County and the Florida Keys for various
endangered plant species and nonnative, invasive species.
Summary of Factor E
We have analyzed threats from other natural or manmade factors
including: Nonnative, invasive plants; management practices used on
roadsides and disturbed sites (such as mowing, sodding, and herbicide
use); pesticide spraying and its effects on pollinators; environmental
stochasticity; effects from small population size and isolation; and
the effects of climate change, including SLR. The related risks from
hurricanes and storm surge act together to impact populations of all
four plants. Some of these threats (e.g., nonnative species) may be
reduced on public lands due to active programs by Federal, State, and
county land managers. Many of the remaining populations of these plants
are small and geographically isolated, and genetic variability is
likely low, increasing the inherent risk due to overall low resilience
of these plants.
Cumulative Effects of Threats
When two or more threats affect populations of the four plants, the
effects of those threats could interact or become compounded, producing
a cumulative adverse effect that is greater than the impact of either
threat alone. The most obvious cases in which cumulative adverse
effects would be significant are those in which small populations
(Factor E) are affected by threats that result in destruction or
modification of habitat (Factor A). The limited distributions and small
population sizes of many populations of the four plants make them
extremely susceptible to the detrimental effects of further habitat
modification, degradation, and loss, as well as other anthropogenic
threats. Mechanisms leading to the decline of the four plants, as
discussed above, range from local (e.g., agriculture) to regional
(e.g., development, fragmentation, nonnative species) to global (e.g.,
climate change, SLR) influences. The synergistic effects of threats,
such as impacts from hurricanes on a species with a limited
distribution and small populations, make it difficult to predict
population viability. While these stressors may act in isolation, it is
more probable that many stressors are acting simultaneously (or in
combination) on populations of these four plants, making them more
vulnerable.
Determination
We have carefully assessed the best scientific and commercial data
available regarding the past, present, and future threats to
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii. Numerous
populations of all four plants have been extirpated from these species'
historical ranges, and the primary threats of habitat destruction and
modification resulting from human population growth and development,
agricultural conversion, and inadequate fire management (Factor A);
competition from nonnative, invasive species (Factor E); changes in
climatic conditions, including SLR (Factor E); and natural stochastic
events (Factor E) remain threats for existing populations. Existing
regulatory mechanisms have not led to a reduction or removal of threats
posed to the four plants from these factors (see Factor D discussion,
above). These threats are ongoing, rangewide, and expected to continue
in the future. A significant percentage of populations of Chamaecrista
lineata var. keyensis, Linum arenicola, and Argythamnia blodgettii are
relatively small and isolated from one another, and their ability to
recolonize suitable habitat is unlikely without human intervention, if
at all. The threats have had and will continue to have substantial
adverse effects on the four plants and their habitats. Although
attempts are ongoing to alleviate or minimize some of these threats at
certain locations, all populations appear to be impacted by one or more
threats.
The Act defines an endangered species as ``any species which is in
danger of extinction throughout all or a significant portion of its
range'' and a threatened species as ``any species which is likely to
become an endangered species within the foreseeable future throughout
all or a significant portion of its range.'' As described in detail
above, Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, and Linum arenicola are currently at risk throughout all of
their range due to the immediacy, severity, significance, timing, and
scope of those threats. Impacts from these threats are ongoing and
increasing; singly or in combination, these threats place these three
plants in danger of extinction. The risk of extinction is high because
the populations are small, are isolated, and have limited to no
potential for recolonization. Numerous threats are currently ongoing
and are likely to continue in the foreseeable future, at a high
intensity and across the entire range of these plants. Furthermore,
natural stochastic events and changes in climatic conditions pose a
threat to the persistence of these plants, especially in light of the
fact these events cannot be controlled and mitigation measures have yet
to be addressed. Individually and collectively, all these threats can
contribute to the local extirpation and potential extinction of these
plant species. Because these threats are placing them in danger of
extinction throughout their ranges, we have determined that each of
these three plants meets the definition of an endangered species
throughout their ranges.
Throughout its range, Argythamnia blodgettii faces threats similar
to the
[[Page 66862]]
other three plant species that are the subjects of this rule. However,
we find that endangered species status is not appropriate for A.
blodgettii. While we have evidence of threats under Factors A, D, and E
affecting the species, insufficient data are available to identify the
trends in extant populations. Twenty populations are extant, 15 are
extirpated, and we are uncertain of the status of 15 populations that
have not been surveyed in 15 years or more. Additionally, data show
that the threat of habitat loss from sea level rise is not as severe
for this species. Also, A. blodgettii is likely less vulnerable because
of the larger number of sites where it occurs throughout Miami-Dade and
Monroe Counties. Further, A. blodgettii is the only one of the four
plants species that occurs in ENP, where a population of over 2,000
plants is stable and where prescribed fire and other management
activities that benefit A. blodgettii are conducted on a regular basis.
Therefore, based on the best available information,
Significant Portion of the Range (SPR)
Under the Act and our implementing regulations, a species may
warrant listing if it is endangered or threatened throughout all or a
significant portion of its range. The threats to the survival of
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii occur throughout
these species' ranges and are not restricted to any particular
significant portion of those ranges. Accordingly, our assessment and
determination applies to each of the four plants throughout its entire
range. Because we have determined that Chamaecrista lineata var.
keyensis, Chamaesyce deltoidea ssp. serpyllum, and Linum arenicola meet
the definition of endangered species, and Argythamnia blodgettii meets
the definition of a threatened species, throughout their ranges, no
portion of their ranges can be ``significant'' for purposes of the
definitions of ``endangered species'' and ``threatened species.'' See
the Service's SPR Policy (79 FR 37578; July 1, 2014).
Therefore, on the basis of the best available scientific and
commercial information, we list Chamaecrista lineata var. keyensis,
Chamaesyce deltoidea ssp. serpyllum, and Linum arenicola as endangered
species in accordance with sections 3(6) and 4(a)(1) of the Act. We
find that threatened species status is not appropriate for Chamaecrista
lineata var. keyensis, Chamaesyce deltoidea ssp. serpyllum, and Linum
arenicola because of the contracted range of each species and because
the threats are occurring rangewide, are ongoing, and are expected to
continue into the future. We find that A. blodgettii is likely to
become an endangered species within the foreseeable future throughout
all or a significant portion of its range, and we list the species as a
threatened species in accordance with sections 3(20) and 4(a)(1) of the
Act.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Act include recognition, recovery actions,
requirements for Federal protection, and prohibitions against certain
practices. Recognition through listing results in public awareness, and
conservation by Federal, State, Tribal, and local agencies; private
organizations; and individuals. The Act encourages cooperation with the
States and other countries and calls for recovery actions to be carried
out for listed species. The protection required by Federal agencies and
the prohibitions against certain activities are discussed, in part,
below.
The primary purpose of the Act is the conservation of endangered
and threatened species and the ecosystems upon which they depend. The
ultimate goal of such conservation efforts is the recovery of these
listed species, so that they no longer need the protective measures of
the Act. Subsection 4(f) of the Act calls for the Service to develop
and implement recovery plans for the conservation of endangered and
threatened species. The recovery planning process involves the
identification of actions that are necessary to halt or reverse the
species' decline by addressing the threats to its survival and
recovery. The goal of this process is to restore listed species to a
point where they are secure, self-sustaining, and functioning
components of their ecosystems.
Recovery planning includes the development of a recovery outline
shortly after a species is listed and preparation of a draft and final
recovery plan. The recovery outline guides the immediate implementation
of urgent recovery actions and describes the process to be used to
develop a recovery plan. Revisions of the plan may be done to address
continuing or new threats to the species, as new substantive
information becomes available. The recovery plan also identifies
recovery criteria for review of when a species may be ready for
downlisting or delisting, and methods for monitoring recovery progress.
Recovery plans also establish a framework for agencies to coordinate
their recovery efforts and provide estimates of the cost of
implementing recovery tasks. Recovery teams (composed of species
experts, Federal and State agencies, nongovernmental organizations, and
stakeholders) are often established to develop recovery plans. If these
four plant species are listed, a recovery outline, draft recovery plan,
and the final recovery plan will be available on our Web site (http://www.fws.gov/endangered), or from our South Florida Ecological Services
Field Office (see FOR FURTHER INFORMATION CONTACT).
Implementation of recovery actions generally requires the
participation of a broad range of partners, including other Federal
agencies, States, Tribes, nongovernmental organizations, businesses,
and private landowners. Examples of recovery actions include habitat
restoration (e.g., restoration of native vegetation), research, captive
propagation and reintroduction, and outreach and education. The
recovery of many listed species cannot be accomplished solely on
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires
cooperative conservation efforts on private, State, and Tribal lands.
If these four plant species are listed, funding for recovery actions
will be available from a variety of sources, including Federal budgets,
State programs, and cost share grants for non-Federal landowners, the
academic community, and nongovernmental organizations. In addition,
pursuant to section 6 of the Act, the State of Florida would be
eligible for Federal funds to implement management actions that promote
the protection or recovery of the four plants. Information on our grant
programs that are available to aid species recovery can be found at:
http://www.fws.gov/grants.
Please let us know if you are interested in participating in
recovery efforts for Chamaecrista lineata var. keyensis, Chamaesyce
deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia blodgettii.
Additionally, we invite you to submit any new information on these
plants whenever it becomes available and any information you may have
for recovery planning purposes (see FOR FURTHER INFORMATION CONTACT).
Section 7(a) of the Act requires Federal agencies to evaluate their
actions with respect to any species that is listed as an endangered or
threatened species and with respect to its critical habitat, if any is
designated. Regulations implementing this interagency cooperation
provision of the Act are codified at 50 CFR part 402. Section
[[Page 66863]]
7(a)(2) of the Act requires Federal agencies to ensure that activities
they authorize, fund, or carry out are not likely to jeopardize the
continued existence of the species or destroy or adversely modify its
critical habitat. If a Federal action may affect a listed species or
its critical habitat, if designated, the responsible Federal agency
must enter into consultation with the Service.
Federal agency actions within the species' habitat that may require
consultation as described in the preceding paragraph include management
and any other landscape-altering activities on Federal lands
administered by the Service, NPS, and Department of Defense; issuance
of section 404 Clean Water Act (33 U.S.C. 1251 et seq.) permits by the
U.S. Army Corps of Engineers; construction and management of gas
pipeline and power line rights-of-way by the Federal Energy Regulatory
Commission; construction and maintenance of roads or highways by the
Federal Highway Administration; and disaster relief efforts conducted
by the Federal Emergency Management Agency.
With respect to endangered plants, prohibitions outlined at 50 CFR
17.61 make it illegal for any person subject to the jurisdiction of the
United States to import or export, transport in interstate or foreign
commerce in the course of a commercial activity, sell or offer for sale
in interstate or foreign commerce, or to remove and reduce to
possession any such plant species from areas under Federal
jurisdiction. In addition, for endangered plants, the Act prohibits
malicious damage or destruction of any such species on any area under
Federal jurisdiction, and the removal, cutting, digging up, or damaging
or destroying of any such species on any other area in knowing
violation of any State law or regulation, or in the course of any
violation of a State criminal trespass law. Exceptions to these
prohibitions are outlined at 50 CFR 17.62. With respect to threatened
plants, 50 CFR 17.71 provides that, with certain exceptions, all of the
prohibitions outlined at 50 CFR 17.61 for endangered plants also apply
to threatened plants. Permit exceptions to the prohibitions for
threatened plants are outlined at 50 CFR 17.72.
Preservation of native flora of Florida through Florida Statutes
581.185, sections (3)(a) and (3)(b), provide limited protection to
species listed in the State of Florida Regulated Plant Index including
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii, as described
under the Factor D discussion, above. Federal listing will increase
protection for these plants by making violations of section 3 of the
Florida Statute punishable as a Federal offense under section 9 of the
Act. This would provide increased protection from unauthorized
collecting and vandalism for the plants on State and private lands,
where they might not otherwise be protected by the Act, and would
increase the severity of the penalty for unauthorized collection,
vandalism, or trade in these plants.
The Service acknowledges that it cannot fully address some of the
natural threats facing Chamaecrista lineata var. keyensis, Chamaesyce
deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia blodgettii,
(e.g., hurricanes, storm surge) or even some of the other significant,
long-term threats (e.g., climatic changes, SLR). However, through
listing, we can provide protection to the known populations and any new
population of these plants that may be discovered (see discussion
below). With listing, we can also influence Federal actions that may
potentially impact these plants (see discussion below); this is
especially valuable if these plants are found at additional locations.
With listing, we will also be better able to deter illicit collection
and trade.
We may issue permits to carry out otherwise prohibited activities
involving endangered or threatened plants under certain circumstances.
Regulations governing permits for endangered plants are codified at 50
CFR 17.62, and for threatened plants at 50 CFR 17.72. With regard to
endangered plants, the Service may issue a permit authorizing any
activity otherwise prohibited by 50 CFR 17.61 for scientific purposes
or for enhancing the propagation or survival of endangered plants.
It is our policy, as published in the Federal Register on July 1,
1994 (59 FR 34272), to identify to the maximum extent practicable at
the time a species is proposed for listing or listed, those activities
that would or would not constitute a violation of section 9 of the Act.
The intent of this policy is to increase public awareness of the effect
of a final listing on proposed and ongoing activities within the range
of the species. Based on the best available information, the following
actions may potentially result in a violation of section 9, of the Act;
this list is not comprehensive:
(1) Import any such species into, or export any of the four plant
species from, the United States.
(2) Remove and reduce to possession any of the four plant species
from areas under Federal jurisdiction; maliciously damage or destroy
any of the four plant species on any such area; or remove, cut, dig up,
or damage or destroy any of the four plant species on any other area in
knowing violation of any law or regulation of any State or in the
course of any violation of a State criminal trespass law.
(3) Deliver, receive, carry, transport, or ship in interstate or
foreign commerce, by any means whatsoever and in the course of a
commercial activity, any of the four plant species.
(4) Sell or offer for sale in interstate or foreign commerce any of
the four plant species.
(5) Introduce any nonnative wildlife or plant species to the State
of Florida that compete with or prey upon Chamaecrista lineata var.
keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, or
Argythamnia blodgettii.
(6) Release any unauthorized biological control agents that attack
any life stage of Chamaecrista lineata var. keyensis, Chamaesyce
deltoidea ssp. serpyllum, Linum arenicola, or Argythamnia blodgettii.
(7) Manipulate or modify, without authorization, the habitat of
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, or Argythamnia blodgettii on Federal lands.
Questions regarding whether specific activities would constitute a
violation of section 9 of the Act should be directed to the Field
Supervisor of the Service's South Florida Ecological Services Field
Office (see FOR FURTHER INFORMATION CONTACT). Requests for copies of
regulations regarding listed species and inquiries about prohibitions
and permits should be addressed to the U.S. Fish and Wildlife Service,
Ecological Services Division, Endangered Species Permits, 1875 Century
Boulevard, Atlanta, GA 30345 (phone 404-679-7140; fax 404-679-7081).
When Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii are listed under
the Act, the State of Florida's Endangered Species Act (Florida
Statutes 581.185) is automatically invoked, which also prohibits take
of these plants and encourages conservation by State government
agencies. Further, the State may enter into agreements with Federal
agencies to administer and manage any area required for the
conservation, management, enhancement, or protection of endangered
species (Florida Statutes 581.185). Funds for these activities can be
made available
[[Page 66864]]
under section 6 of the Act (Cooperation with the States). Thus, the
Federal protection afforded to these plants by listing them as
endangered species will be reinforced and supplemented by protection
under State law.
Activities that the Service believes could potentially harm these
four plants include, but are not limited to:
(1) Actions that would significantly alter the hydrology or
substrate, such as ditching or filling. Such activities may include,
but are not limited to, road construction or maintenance, and
residential, commercial, or recreational development.
(2) Actions that would significantly alter vegetation structure or
composition, such as clearing vegetation for construction of
residences, facilities, trails, and roads.
(3) Actions that would introduce nonnative species that would
significantly alter vegetation structure or composition. Such
activities may include, but are not limited to, residential and
commercial development, and road construction.
(4) Application of herbicides, or release of contaminants, in areas
where these plants occur. Such activities may include, but are not
limited to, natural resource management, management of rights-of-way,
residential and commercial development, and road construction.
Critical Habitat
Section 3(5)(A) of the Act defines critical habitat as (i) the
specific areas within the geographical area occupied by the species, at
the time it is listed on which are found those physical or biological
features (I) essential to the conservation of the species and (II)
which may require special management considerations or protection; and
(ii) specific areas outside the geographical area occupied by the
species at the time it is listed upon a determination by the Secretary
of the Interior that such areas are essential for the conservation of
the species. Section 3(3) of the Act defines conservation as to use and
the use of all methods and procedures which are necessary to bring any
endangered species or threatened species to the point at which the
measures provided pursuant to the Act are no longer necessary.
Section 4(a)(3) of the Act, as amended, and implementing
regulations (50 CFR 424.12), require that, to the maximum extent
prudent and determinable, the Secretary will designate critical habitat
at the time the species is determined to be an endangered or threatened
species. Our regulations (50 CFR 424.12(a)(1)) state that the
designation of critical habitat is not prudent when one or both of the
following situations exist:
(1) The species is threatened by taking or other human activity,
and identification of critical habitat can be expected to increase the
degree of threat to the species, or
(2) Such designation of critical habitat would not be beneficial to
the species.
In our proposed listing rule, we determined that because the
designation of critical habitat will not likely increase the degree of
threat to the species and may provide some measure of benefit, the
designation of critical habitat is prudent for Chamaecrista lineata
var. keyensis, Chamaesyce deltoidea ssp. serpyllum, Linum arenicola,
and Argythamnia blodgettii.
Our regulations (50 CFR 424.12(a)(2)) further state that critical
habitat is not determinable when one or both of the following
situations exists: (1) Information sufficient to perform required
analysis of the impacts of the designation is lacking; or (2) the
biological needs of the species are not sufficiently well known to
permit identification of an area as critical habitat. On the basis of a
review of available information, we find that critical habitat for
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, Linum arenicola, and Argythamnia blodgettii is not
determinable because the specific mapping and economic information
sufficient to perform the required analysis of the impacts of the
designation is currently lacking. We are still in the process of
obtaining more information needed to properly evaluate the economic
impacts of designation. We intend to publish a proposed rule
designating critical habitat for Chamaecrista lineata var. keyensis,
Chamaesyce deltoidea ssp. serpyllum, Linum arenicola, and Argythamnia
blodgettii by the end of fiscal year 2017.
Required Determinations
National Environmental Policy Act (42 U.S.C. 4321 et seq.)
We have determined that environmental assessments and environmental
impact statements, as defined under the authority of the National
Environmental Policy Act need not be prepared in connection with
listing a species as an endangered or threatened species under the
Endangered Species Act. We published a notice outlining our reasons for
this determination in the Federal Register on October 25, 1983 (48 FR
49244).
References Cited
A complete list of references cited in this rulemaking is available
on the Internet at http://www.regulations.gov and upon request from the
South Florida Ecological Services Field Office (see FOR FURTHER
INFORMATION CONTACT).
Authors
The primary authors of this final rule are the staff members of the
South Florida Ecological Services Field Office.
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Regulation Promulgation
Accordingly, we amend part 17, subchapter B of chapter I, title 50
of the Code of Federal Regulations, as follows:
PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS
0
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 1531-1544; and 4201-4245, unless
otherwise noted.
0
2. Amend Sec. 17.12(h) by adding entries for Argythamnia blodgettii,
Chamaecrista lineata var. keyensis, Chamaesyce deltoidea ssp.
serpyllum, and Linum arenicola, in alphabetical order under FLOWERING
PLANTS, to the List of Endangered and Threatened Plants to read as
follows:
Sec. 17.12 Endangered and threatened plants.
* * * * *
(h) * * *
[[Page 66865]]
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Listing citations
Scientific name Common name Where listed Status and applicable
rules
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Flowering Plants
* * * * * * *
Argythamnia blodgettii........... Blodgett's Wherever found..... T [Insert Federal
silverbush. Register
citation];
September 29,
2016.
* * * * * * *
Chamaecrista lineata var. Big Pine partridge Wherever found..... E [Insert Federal
keyensis. pea. Register
citation];
September 29,
2016.
* * * * * * *
Chamaesyce deltoidea ssp. Wedge spurge....... Wherever found..... E [Insert Federal
serpyllum. Register
citation];
September 29,
2016.
* * * * * * *
Linum arenicola.................. Sand flax.......... Wherever found..... E [Insert Federal
Register
citation];
September 29,
2016.
* * * * * * *
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Dated: September 21, 2016.
Stephen Guertin,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2016-23546 Filed 9-28-16; 8:45 am]
BILLING CODE 4333-15-P