Federal Register: December 6, 2007 (Volume 72, Number 234)
DOCID: fr06de07-20 FR Doc E7-23416
DEPARTMENT OF THE INTERIOR
Veterans Affairs Department
CFR Citation: 50 CFR Part 17
NOTICE: Part III
DOCID: fr06de07-20
DOCUMENT ACTION: Notice of review.
SUBJECT CATEGORY:
Endangered and Threatened Wildlife and Plants; Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Notice of Findings on Resubmitted Petitions; Annual Description of Progress on Listing Actions
DATES: We will accept comments on the most recent Candidate Notice of Review at any time.
DOCUMENT SUMMARY:
In this Candidate Notice of Review (CNOR), we, the U.S. Fish and Wildlife Service (Service), present an updated list of plant and animal species native to the United States that we regard as candidates for or have proposed for addition to the Lists of Endangered and Threatened Wildlife and Plants under the Endangered Species Act of 1973, as amended. Identification of candidate species can assist environmental planning efforts by providing advance notice of potential listings, allowing landowners and resource managers to alleviate threats and thereby possibly remove the need to list species as endangered or threatened. Even if we subsequently list a candidate species, the early notice provided here could result in more options for species management and recovery by prompting candidate conservation measures to alleviate threats to the species.
The CNOR summarizes the status and threats that we evaluated in order to determine that species qualify as candidates and to assign a listing priority number (LPN) to each species, or to remove species from candidate status. Additional material that we relied on is available in the Species Assessment and Listing Priority Assignment Forms (species assessment forms, previously called candidate forms) for each candidate species.
Overall, this CNOR recognizes 5 new candidates, changes the LPN for 29 candidates, and removes 4 species from candidate status. Combined with other decisions for individual species that were published separately from this CNOR, the new number of species that are candidates for listing is 280.
We request additional status information that may be available for the 280 candidate species identified in this CNOR. We will consider this information in preparing listing documents and future revisions to the notice of review, as it will help us in monitoring changes in the status of candidate species and in management for conserving them. We also request information on additional species that we should consider including as candidates as we prepare future updates of this notice.
This document also includes our findings on resubmitted petitions and describes our progress in revising the Lists of Endangered and Threatened Wildlife and Plants during the period September 26, 2006, through September 30, 2007.
SUMMARY:
Interior Department, Fish and Wildlife Service,
SUPPLEMENTAL INFORMATION
Candidate Notice of Review
Background
The Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.) (Act), requires that we identify species of wildlife and plants that are endangered or threatened, based on the best available scientific and commercial information. As defined in section 3 of the Act, an endangered species is any species which is in danger of extinction throughout all or a significant portion of its range, and a threatened species is any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range. Through the Federal rulemaking process, we add species that meet these definitions to the List of Endangered and Threatened Wildlife at 50 CFR 17.11 or the List of Endangered and Threatened Plants at 50 CFR 17.12. As part of this program, we maintain a list of species that we regard as candidates for listing. A candidate species is one for which we have on file sufficient information on biological vulnerability and threats to support a proposal to list as endangered or threatened, but for which preparation and publication of a proposal is precluded by higher priority listing actions.
We maintain this list of candidates for a variety of reasons: to notify the public that these species are facing threats to their survival; to provide advance knowledge of potential listings that could affect decisions of environmental planners and developers; to provide information that may stimulate and guide conservation efforts that will remove or reduce threats to these species and possibly make listing unnecessary; to solicit input from interested parties to help us identify those candidate species that may not require protection under the Act or additional species that may require the Act's protections; and to solicit necessary information for setting priorities for preparing listing proposals. We strongly encourage collaborative conservation efforts for candidate species and offer technical and financial assistance to facilitate such efforts. For additional information regarding such assistance, please contact the appropriate Regional Office listed in SUPPLEMENTARY INFORMATION or visit our Internet Web site, http://endangered.fws.gov/candidates/index.html. Previous Notices of Review
We have been publishing candidate notices of review (CNOR) since
1975. The most recent CNOR (prior to this CNOR) was published on
September 12, 2006 (71 FR 53755). CNORs published since 1994 are
available on our Internet Web site, http://www.fws.gov/endangered/candidates/index.html. For copies of CNORs published prior to 1994,
please contact the Division of
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Conservation and Classification (see ADDRESSES section above).
On September 21, 1983, we published guidance for assigning an LPN for each candidate species (48 FR 43098). Using this guidance, we assign each candidate an LPN of 1 to 12, depending on the magnitude of threats, imminence of threats, and taxonomic status; the lower the LPN, the higher the listing priority (that is, a species with an LPN of 1 would have the highest listing priority). Such a priority ranking guidance system is required under section 4(h)(3) of the Act (15 U.S.C. 1533(h)(3)). As explained below, in using this system we first categorize based on the magnitude of the threat(s), then by the immediacy of the threat(s), and finally by taxonomic status.
Under this priority ranking guidance system, magnitude of threat can be either ``high'' or ``moderate to low.'' This criterion helps ensure that the species facing the greatest threats to their continued existence receive the highest listing priority. It is important to recognize that all candidate species face threats to their continued existence, so the magnitude of threats is in relative terms. When evaluating the magnitude of the threat(s) facing the species, we consider information such as: the number of populations and/or extent of range of the species affected by the threat(s); the biological significance of the affected population(s), taking into consideration the life history characteristics of the species and its current abundance and distribution; whether the threats affect the species in only a portion of its range, and if so the likelihood of persistence of the species in the unaffected portions; and whether the effects are likely to be permanent.
As used in our priority ranking system, immediacy of threat is categorized as either ``imminent'' or ``nonimminent'' and is not a measure of how quickly the species is likely to become extinct if the threats are not addressed; rather, immediacy is based on when the threats will begin. If a threat is currently occurring or likely to occur in the very near future, we classify the threat as imminent. Determining the immediacy of threats helps ensure that species facing actual, identifiable threats are given priority for listing proposals over those for which threats are only potential or species intrinsically vulnerable to certain types of threats but not known to be presently facing such threats.
Our priority ranking system has three categories for taxonomic status: Species that are the sole members of a genus; full species (in a genus that has more than one species); and subspecies, distinct population segments of vertebrate species, and species for which listing is appropriate in a significant portion of their range.
The result of the ranking system is that we assign each candidate a listing priority number of 1 to 12. For example, if the threat(s) is of high magnitude, with immediacy classified as imminent, the listable entity is assigned an LPN of 1, 2, or 3 based on its taxonomic status (e.g., if the species is the only member of a genus, it would be assigned to the LPN 1 category, a full species to LPN 2, and a subspecies, DPS, or significant portion of the range to LPN 3). In summary, the LPN ranking system provides a basis for making decisions about the relative priority for preparing a proposed rule to list a given species. No matter which LPN we assign to a species, each species included in this notice as a candidate is one for which we have sufficient information to prepare a proposed rule to list it because it is in danger of extinction or likely to become endangered within the foreseeable future throughout all or a significant portion of its range.
For more information on the process and standards used in assigning
LPNs, a copy of the guidance is available on our Web site at: http://www.fws.gov/endangered/policy/index.html. For more information on the
LPN assigned to a particular species, the species assessment for each
candidate contains the LPN chart and a detailed explanation of the
rationale for the determination of the magnitude and imminence of
threat(s) and assignment of the LPN; that information is summarized in this CNOR.
This revised notice supersedes all previous animal, plant, and combined candidate notices of review.
Summary of This CNOR
Since publication of the CNOR on September 12, 2006 (71 FR 53756), we reviewed the available information on candidate species to ensure that a proposed listing is justified for each species, and reevaluated the relative LPN assigned to each species. We also evaluated the need to emergencylist any of these species, particularly species with high priorities (i.e., species with LPNs of 1, 2, or 3). This review and reevaluation ensures that we focus conservation efforts on those species at greatest risk first. (In addition to reviewing candidate species, we have worked on numerous findings in response to petitions to list species, and on proposed and final determinations for rules to list species under the Act; some of these findings and determinations have been completed and published in the Federal Register, while work on others is still under way. See the discussions of Preclusion and Expeditious Progress, below, for details.)
Based on our review of the best available scientific and commercial information, with this CNOR we identify 5 new candidate species (see New Candidates, below), change the LPN for 28 candidates (see Listing Priority Changes in Candidates, below) and determine that listing proposals are not warranted for 4 species and thus remove them from candidate status (see Candidate Removals, below). Combined with the other decisions published separately from this CNOR for individual species that previously were candidates, a total of 280 species (including 139 plant and 141 animal species) are now candidates awaiting preparation of rules proposing their listing. These 280 species, along with the 2 species currently proposed for listing, are included in Table 1. (Note, regarding the two species currently proposed for listing, we proposed one since the last CNOR and we proposed the other prior to the last CNOR.)
Table 2 includes 8 species identified in the previous CNOR as either proposed for listing or classified as candidates that are no longer in those categories. This includes four species for which we published separate findings that listing is not warranted, plus the four species that we have determined do not warrant preparation of a rule to propose listing and therefore have removed from candidate status in this CNOR.
New Candidates
Below we present brief summaries of five new candidates that we are
recognizing in this CNOR, including one species of mammal, one
amphibian, one fish, one snail, and one plant. Complete information,
including references, can be found in the species assessment forms. You
may obtain a copy of these forms from the Regional Office having the
lead for the species, or from our Internet Web site (http://endangered.fws.gov/candidates/index.html ). For each of these five
species, we find that we have on file sufficient information on
biological vulnerability and threats to support a proposal to list as
endangered or threatened, but that preparation and publication of a
proposal is precluded by higherpriority listing actions (i.e., these
meet our definition of a candidate species). We also note below that
one other species, Casey's June beetle (an insect), was identified as a candidate
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earlier this year in a separate finding published in the Federal Register.
Mammals
New Mexico meadow jumping mouse (Zapus hudsonius luteus)The following summary is based on information contained in our files. The New Mexico meadow jumping mouse (jumping mouse) is endemic to New Mexico, Arizona, and a small area of southern Colorado. The jumping mouse nests in dry soils but uses moist, streamside, dense riparian/ wetland vegetation. Recent genetic studies confirm that the New Mexico meadow jumping mouse is a distinct subspecies from other Zapus hudsonius subspecies, confirming the currently accepted subspecies designation.
The threats that have been identified are excessive grazing pressure, water use and management, highway reconstruction, development, and recreation. Surveys conducted in 2005 and 2006 documented a drastic decline in the number of occupied localities and suitable habitat across the range of the species in New Mexico and Arizona. Of the original 98 known historical localities, there are now only 10 known extant localities in New Mexico, 1 in Arizona, and an additional 8 localities that have not been surveyed since the early to mid 1990s. Moreover, the highly fragmented nature of its distribution is also a major contributor to the vulnerability of this species and increases the likelihood of very small, isolated populations being extirpated. The paucity of secure populations, and the destruction, modification, or curtailment of its habitat, poses the most immediate threats to this species. Because the threats affect the jumping mouse in all but two of the extant localities, the threats are of a high magnitude. These threats are currently occurring and, therefore, are imminent. Thus, we assigned an LPN of 3 to this subspecies. Amphibians
Arizona treefrog, Huachuca/Canelo Distinct Population Segment (DPS) (Hyla wrightorum)The following summary is based on information in our files. The population is known from three general localities at Rancho Los Fresnos, northern Sonora, Mexico, and 1315 verified localities and one unverified locality in the Huachuca Mountains and Canelo Hills of Arizona. The population is both discrete and significant in accordance with our February 7, 1996, DPS policy (61 FR 4721). Evidence exists that the DPS persists in an ecological setting that is unique for the taxon, that loss of the population segment would result in a significant gap in the range of the taxon, and that the population segment differs markedly from other populations of the species in its genetic characteristics. The population is discrete from the Mogollon Rim population of Arizona and New Mexico based on a physical separation of 130 miles, and from the Sierra Madre Occidental population in Sonora and Chihuahua, Mexico by 145 miles.
The most significant threats to the existence of the Huachuca/ Canelo population of the Arizona treefrog are, in order of importance, habitat loss or degradation and direct mortality due to catastrophic fire; loss of populations due to drought or floods, which may be exacerbated by climatic extremes; predation by introduced species; and habitat degradation caused by livestock grazing, offhighway vehicles, and environmental contamination. The effects of these threats are exacerbated by small population sizes and low genetic diversity, as the Huachuca/Canelo Hills population has less than 20 known localities, each with observed breeding populations of 230 individuals. Taken together, these threats are of high magnitude, particularly in Arizona. The threats are also imminent or ongoing, particularly the threat of catastrophic wildfire; there have been several recent catastrophic fires in the Huachuca Mountains. Therefore, we have assigned an LPN of 3 to this population.
Fish
Laurel dace (Phoxinus saylori)The laurel dace is a rare minnow known only from three independent systems on the Walden Ridge section of the Cumberland Plateau, including Soddy Creek, Sale Creek, and Piney River. The primary threats to the laurel dace stem from impacts to riparian and instream habitat resulting from incompatible land uses. The riparian habitats associated with some streams occupied by laurel dace have been affected by extensive timber removal activities on Walden Ridge in their vicinity; these activities often do not employ adequate streamside management zones or best management practices for road construction. Proposed projects, including installation of a water line that would cross occupied streams and construction of an impoundment on a tributary to an occupied stream, present additional direct and indirect threats to laurel dace habitat in the headwaters of Sale and Soddy creeks. We believe that the threat of habitat degradation from siltation across the range of laurel dace and the localized threats facing populations in Sale and Soddy creeks combined with vulnerable status of the populations in Soddy and Sale creeks constitute threats collectively of high magnitude, but are nonimminent. Therefore, we assigned the laurel dace an LPN of 5.
Snails
San Bernardino springsnail (Pyrgulopsis bernardina)This species is endemic to one natural spring, Snail Spring, on private lands, and one artificial spring, Tule Spring, on National Wildlife Refuge lands, in the Rio Yaqui basin of Cochise County, Arizona. The species was formerly known from six to eight springs. Known threats include water diversion, spring modification, and contaminants, while suspected threats include livestock grazing and groundwater depletion. The San Bernardino National Wildlife Refuge is actively managing Tule Spring and is attempting to acquire the property containing Snail Spring. However, the Refuge cannot address the potential threat from groundwater depletion without assistance from local stakeholders. The magnitude of threats is high because the limited distribution of this narrow endemic makes any catastrophic event likely to result in extinction of the species. The threats are ongoing and therefore imminent. Thus, we have assigned an LPN of 2 for the San Bernardino springsnail.
Insects
Casey's June beetle (Dinacoma caseyi)We previously announced candidate status for this species in a separate warranted but precluded 12month petition finding published on July 5, 2007 (72 FR 36635). Plants
Eriogonum corymbosum var. nilesii (Las Vegas buckwheat)The following information is based on information contained in our files. The Las Vegas buckwheat is a woody perennial shrub up to 4 feet high with a mounding shape. The flowers of this plant are numerous, small and yellow with small bract like leaves at the base of each flower. The Las Vegas buckwheat is very conspicuous when flowering in late September and early October. It is restricted to gypsum soil outcroppings in Clark and Lincoln Counties, Nevada. Only recently has the taxonomy of the subspecies been confirmed using molecular genetic analyses.
Loss of habitat from development is a significant threat with over
95 percent of the historic range and potential habitat of the subspecies lost to development. In 2005, the Las Vegas
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buckwheat was known from nine locations on approximately 1,149 acres.
However, since that time, approximately 289 acres were or soon will be
developed, and the current distribution of the plant occupies 892
acres. In addition, OHV activity and other public land uses (casual
public use, mining, and dumping) directly and indirectly threaten over
half of the remaining habitat. To date, regulatory mechanisms to
protect the Las Vegas buckwheat are inadequate. Its designation as a
BLM special status species and limited resource and law enforcement
personnel has not provided adequate protection on lands managed by the
BLM. The Las Vegas buckwheat is not protected by the State of Nevada or
any other regulatory mechanisms on other federal lands. We have
determined that candidate status is warranted for the Las Vegas
buckwheat as a result of threats to the remaining 892 acres of Las
Vegas buckwheat. Conservation measures are being developed that could
reduce the amount of occupied habitat at risk, but we believe it would
be premature to consider these measures sufficiently complete as to
remove these threats. The magnitude of threats is high since the more
significant threats (development and surface mining) would result in
direct mortality of the plants in over half of its' habitat. While both
development and mining are very likely to occur in the future, they are
not expected to happen in the immediate future, and thus, the threats
are nonimminent. Accordingly, we assigned the Las Vegas buckwheat an LPN of 6.
Listing Priority Changes in Candidates
We reviewed the LPN for all candidate species and are changing the numbers for the following species. Some of the changes reflect actual changes in either the magnitude or imminence of the threats, and in one case, the LPN change reflects a change in the taxonomy of the species. For some species, our changes in the LPN reflect efforts to ensure national consistency as well as closer adherence to the 1983 guidelines in assigning these numbers, rather than a change in the nature of the threats.
Birds
Friendly grounddove, American Samoa DPS (Gallicolumba stairi stairi)The following summary is based on information contained in our files. The genus Gallicolumba is distributed throughout the Pacific and Southeast Asia. The genus is represented in the oceanic Pacific by six species. Three are endemic to Micronesian islands or archipelagos, two are endemic to island groups in French Polynesia, and G. stairi is endemic to Samoa, Tonga, and Fiji. All six species have some level of threatened status on the International Union for Conservation of Nature and Natural Resources (IUCN) Red List. Some authors recognize two subspecies of the friendly grounddove, one, slightly smaller, in the Samoan archipelago (G. s. stairi), and one in Tonga and Fiji (G. s. vitiensis), but morphological differences between the two are minimal.
In American Samoa, the friendly grounddove has been found on the islands of Ofu and Olosega (Manua Group). Threats to this subspecies have not changed over the past year. Of the primary threats to the subspecies (predation by nonnative species and natural catastrophes such as hurricanes), predation by nonnative species is thought to be occurring now, and predation likely has been occurring for several decades. This predation may be an important impediment to increasing the population. Predation by introduced species has played a significant role in reducing, limiting, and extirpating populations of island birds, especially groundnesters, in the Pacific and other locations worldwide. Nonnative predators known or thought to occur in the range of the friendly grounddove in American Samoa are feral cats (Felis catus), Polynesian rats (Rattus exulans), black rats (R. rattus), and Norway rats (R. norvegicus).
In January 2004 and February of 2005, hurricanes virtually destroyed the habitat of G. stairi in an area on Olosega Island where the species had been most frequently recorded. Although this species has coexisted with severe storms for millennia, this example illustrates the potential for natural disturbance to exacerbate the effect of anthropogenic disturbance on small populations. Consistent monitoring using a variety of methods over the last 5 years yielded few observations of this taxon in American Samoa. The total population size is poorly known, but is unlikely to number more than a few hundred pairs. The past five years or so of surveys have revealed no change in the relative abundance of this taxon in American Samoa. The distribution of the friendly grounddove is limited to steep, forested slopes with an open understory and a substrate of fine scree or exposed earth; this habitat is not common in American Samoa. We revised the LPN from a 6 to a 9 to better reflect the fact that the threats posed to the friendly grounddove (its small population size and nonnative predators), while imminent and occurring throughout its range, are believed to be of a moderate magnitude rather than a high magnitude.
Kittlitz's Murrelet (Brachyramphus brevirostris)Kittlitz's murrelet is a small diving seabird whose entire North American population, and most of the world's population, inhabits Alaskan coastal waters discontinuously from Point Lay south to northern portions of Southeast Alaska. Kittlitz's murrelets are associated with tidewater glaciers. The current population estimate for Kittlitz's murrelets in Alaska is approximately 16,700 birds, a decline of 74 to 84 percent during the past 10 to 20 years. New survey information supports and strengthens the negative population trend estimates that have been previously reported.
Threats to Kittlitz's murrelets include largescale processes such
as global climate change and marine climate regime shift. These large
scale processes may influence Kittlitz's murrelet survival and
reproduction. Glacial retreat, a global phenomenon that affects many of
the glaciers with which Kittlitz's murrelets are associated, is
associated with changing forage fish availability and may result in
increased predation from corvids (retreat of glaciers allows corvids
easier access to murrelets on which they prey). Even if the causes of
rapid climate warming were curbed today, feedback mechanisms would
result in the continued retreat of tidewater glaciers into the
foreseeable future. In addition, the declining population trend makes
this species particularly susceptible to ongoing threats from other
human activities, including oil spills, bycatch in commercial gillnet
fisheries, and disturbance by tour boats. Kittlitz's murrelets are
believed to have been seriously affected by the Exxon Valdez oil spill
in Prince William Sound (PWS) in 1989. Estimates of direct mortality of
Kittlitz's murrelets from this oil spill constituted a loss of 7 to15
percent of the PWS population. Catastrophic events such as oil spills
could have a significant negative effect on the population of this
already diminished species. Susceptibility to mortality as bycatch in
commercial fishing could be a significant factor in their population
decline; Kittlitz's murrelets are caught in gill nets in numbers
disproportionate to their density. In PWS, salmon gillnet fisheries
occur each summer in or near Kittlitz's murrelet habitat. Kittlitz's
murrelets represented 5 percent and 30 percent of murrelet bycatch in
gillnets during 1990 and 1991, respectively. Tour boat visitation to
glacial fjords is a growing industry, and this activity may
increasingly disrupt Kittlitz's murrelet feeding behavior; tour boats [[Page 69038]]
may provide artificial perch sites for avian predators. The number of
cruise ships allowed into Glacier Bay has increased 30 percent since
1985, while smaller charter boats and private boats have increased 8
percent and 15 percent, respectively. An increase in tour boat
operations has been noted in Kenai Fjords National Park as well.
Disturbance can disrupt feeding birds and persistent boat traffic may prevent murrelets from using high quality foraging areas.
Based on the observed population trajectory and the severity of present threats (rapid glacial retreat, acute and chronic oil spills, commercial gillnet fishing, and human disturbance from tour boats), the threats to this species are high in magnitude and imminent. We changed the LPN from a 5 to a 2 to reflect that the threats to this species are ongoing.
Xantus's murrelet (Synthliboramphus hypoleucus)The Xantus's murrelet is a small seabird in the Alcid family that occurs along the west coast of North America in the United States and Mexico. The species has a limited breeding distribution, only nesting on the Channel Islands in southern California and on islands off the west coast of Baja California, Mexico. Although data on population trends are scarce, the population is suspected to have declined greatly over the last century, mainly due to introduced predators such as rats (Rattus sp.) and feral cats (Felis catus) to nesting islands, with extirpations on three islands in Mexico. A dramatic decline (up to 70 percent) from 1977 to 1991 was detected at the largest nesting colony in southern California, possibly due to high levels of predation on eggs by the endemic deer mouse (Peromyscus maniculatus elusus). Identified threats include introduced predators at nesting colonies, oil spills and oil pollution, reduced prey availability, human disturbance, and artificial light pollution.
Although substantial declines in the Xantus's murrelet population likely occurred over the last century, some of the largest threats are being addressed, and, to some degree, ameliorated. Declines and extirpations at several nesting colonies were thought to have been caused by nonnative predators, which have been removed from many of the islands where they once occurred. Most notably, since 1994, Island Conservation and Ecology Group has systematically removed rats, cats, and dogs from every murrelet nesting colony in Mexico, with the exception of cats and dogs on Guadalupe Island. In 2002, rats were eradicated from Anacapa Island in southern California, which has resulted in improvements in reproductive success at that island. In southern California, there are also plans to remove rats from San Miguel Island, and to restore nesting habitat on Santa Barbara Island through the Montrose Settlements Restoration Project, which may benefit the Xantus's murrelet population at those islands.
Artificial lighting from squid fishing and other vessels, or lights on islands, remains a potential threat to the species. Bright lights make Xantus's murrelets more susceptible to predation, and they can also become disoriented and exhausted from continual attraction to bright lights. Chicks can become disoriented and separated from their parents at sea, which could result in death of the dependent chicks. Highwattage lights on commercial market squid (Loligo opalescens) fishing vessels used at night to attract squid to the surface of the water in the Channel Islands was the suspected cause of unusually high predation on Xantus's murrelets by western gulls and barn owls at Santa Barbara Island in 1999. To address this threat, in 2000, the California Fish and Game Commission required light shields and a limit of 30,000 watts per boat; it is unknown if this is sufficient to reduce impacts. Squid fishing has not occurred at a particularly noticeable level near any of the colonies in the Channel Islands since 1999; however, this remains a potential future threat.
A proposal to build a liquid natural gas (LNG) facility 600 meters (1,969 feet) off the Coronados Islands in Baja California, Mexico, was considered a potential major threat to the species. This island contains one of the largest nesting populations of Xantus's murrelets in the world. Potential impacts of this facility to the nesting colony included bright lights at night from the facility and visiting tanker vessels, noise from the facility or from helicopters visiting the facility, and the threat of oil spills associated with visiting tanker vessels. However, Chevron announced in March 2007 that they have abandoned plans to develop this facility and withdrew their permits. LNG facilities are proposed for construction in the Channel Islands; however, these are early in the complex and longterm planning processes; it is possible that none of these facilities will be built. In addition, none of them are directly adjacent to nesting colonies, where their impacts would be expected to be more significant.
We considered the LNG facility off the Coronados Islands to be an imminent threat of high magnitude, which resulted in the previous listing priority of a 2. While this proposed LNG facility no longer poses a threat, the remaining threats, in particular oil spills, are high in magnitude since they have the potential to cause direct mortality and reduce reproductive success throughout a majority of the species' range. The threats are nonimminent since they are not currently occurring. Therefore, we have changed the LPN from a 2 to a 5.
Reptiles
Louisiana pine snake (Pituophis ruthveni)The Louisiana pine snake (LPS) historically occurred in firemaintained longleafpine ecosystems of westcentral Louisiana and extreme eastcentral Texas. Those ecosystems provided an herbaceous layer necessary to maintain the Louisiana pine snake's primary prey, the Baird's pocket gopher. Current potentially occupied habitat in Louisiana and Texas is estimated to be approximately 300,000 acres, with 70 percent occurring on public lands and 30 percent in private ownership. Results of trapping and radio telemetry surveys suggest that extensive population declines and local extirpations have occurred during the last 50 to 80 years. To address those issues on public lands, a Candidate Conservation Agreement (CCA) was completed in 2003 to maintain and enhance potentially occupied habitat, and protect known Louisianapinesnake populations. Much of the public land is now being managed on longer rotations (i.e., 70+ years) where silvicultural prescriptions include smaller clearcuts, midstory removal, thinning, and prescribed fire. Private lands generally are not managed to support the longleafpine ecosystem and its characteristic herbaceous layer; however, several private landowners with known Louisianapinesnake populations continue to be involved in conservation efforts with reported conservation of more than 2,000 acres in 2006.
Within both the public and private sectors, interest in longleaf
pine restoration appears to be growing and with the appropriate
emphasis could slow or reverse habitat loss trends. To address this and
other issues, the LPS Conservation Group is expanding conservation
efforts through the development of a Comprehensive Conservation Plan
that would build upon the CCA success. Other factors affecting
Louisiana pine snakes throughout its range include low fecundity, which
magnifies other threats and increases the likelihood of local
extinctions, and vehicular mortality, which can significantly affect Louisianapinesnake population and community
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structure. While the magnitude of Louisianapinesnake habitat loss has
been great in the past and the remaining habitat is degraded, habitat
loss does not represent an imminent threat, because the rate of habitat
loss is declining. Additionally, proactive partnerships to address key
management concerns and research needs are resulting in some additional
longleaf pine habitat that is suitable for the Louisiana pine snake or
its prey species. However, while conservation actions have produced
needed results, they have not yet adequately reduced threats to the
species, particularly on private land. The lack of adequate habitat
still poses a threat and when coupled with the very low fecundity rate
and extremely low population size (based on capture rates and
population estimates) make the threat high in magnitude. Overall, due
to nonimminent, highmagnitude threats, we changed the LPN from an 8 to a 5 for this species.
Amphibians
Columbia spotted frog, Great Basin DPS (Rana luteiventris) Currently, Columbia spotted frogs appear to be widely distributed throughout southwestern Idaho, eastern Oregon, and northeastern and central Nevada, but local populations within these general areas appear to be small and isolated from each other. Recent work by researchers in Idaho and Nevada has documented loss of historically known sites, reduced numbers of individuals within local populations, and declines in the reproduction of those individuals. Small highly fragmented populations, characteristic of the majority of existing populations of Columbia spotted frogs in the Great Basin, are highly susceptible to extinction processes. Threats to Columbiaspottedfrog habitat, including water development, improper grazing, mining activities and nonnative species, have and continue to contribute to the degradation and fragmentation of habitat. Emerging fungal diseases, such as chytridiomycosis, and the spread of parasites are contributing factors to Columbiaspottedfrog population declines throughout portions of its range. Effects of climate change such as drought and stochastic (randomly occurring) events such as fire often have detrimental effects to small isolated populations and can often exacerbate existing threats.
A 10year Conservation Agreement and Strategy was signed in September 2003 for both the Northeast and the Toiyabe subpopulations in Nevada. The goals of the conservation agreements are to reduce threats to Columbia spotted frogs and their habitat to the extent necessary to prevent populations from becoming extirpated throughout all or a portion of their historic range and to maintain, enhance, and restore a sufficient number of populations of Columbia spotted frogs and their associated habitat to ensure their continued existence throughout their historical range. Additionally, a Candidate Conservation Agreement with Assurances was completed in 2006 for the Owyhee subpopulation at Sam Noble Springs, Idaho. Because these conservation agreements have reduced the magnitude of the imminent threats from high to moderate, we changed the LPN from a 3 to a 9 for this DPS of the Columbia spotted frog.
Black Warrior waterdog (Necturus alabamensis)The Black Warrior waterdog is a salamander that inhabits streams above the Fall Line within the Black Warrior River Basin in Alabama. There is very little specific locality information available on the historical distribution of the Black Warrior waterdog since little attention was given to this species between its description in 1937 and the 1980s. At that time, there were a total of only 11 known historical records from 4 Alabama counties. Two of these sites have now been inundated by impoundments. Extensive survey work was conducted in the 1990s to look for additional populations. Currently, the species is known from 14 sites in 5 counties.
Waterquality degradation is the biggest threat to the continued existence of the Black Warrior waterdog. Most streams that have been surveyed for the waterdog showed evidence of pollution and many appeared biologically depauperate. Sources of point and nonpoint pollution in the Black Warrior River Basin have been numerous and widespread. Pollution is generated from inadequately treated effluent from industrial plants, sanitary landfills, sewage treatment plants, poultry operations, and cattle feedlots. Surface mining represents another threat to the biological integrity of waterdog habitat. Runoff from old, abandoned coal mines generates pollution through acidification, increased mineralization, and sediment loading. The North River, Locust Fork, and Mulberry Fork, all streams that this species inhabits, are on the Environmental Protection Agency's list of impaired waters. An additional threat to the Black Warrior waterdog is the creation of large impoundments that have flooded thousands of square hectares (acres) of its habitat. These impoundments are likely marginal or unsuitable habitat for the salamander. While the water quality threat is pervasive and problematic, the overall magnitude of the threat is moderate as there has not been a steep rate of decline in this species population. Water quality degradation in the Black Warrior basin is ongoing; therefore, the threats are imminent. We changed the LPN from a 2 to an 8 for this species since the threats are of a moderate rather than high magnitude.
Clams
Fluted kidneyshell (Ptychobranchus subtentum)The fluted kidneyshell is a freshwater mussel (Unionidae) endemic to the Cumberland and Tennessee River systems (Cumberlandian Region) in Alabama, Kentucky, Tennessee, and Virginia. It requires shoal habitats in freeflowing rivers to survive and successfully recruit new individuals into its populations.
This species has been extirpated from numerous regional streams and
is no longer found in the State of Alabama. Habitat destruction and
alteration (e.g., impoundments, sedimentation, and pollutants) are the
chief factors that contributed to its decline. The fluted kidneyshell
was historically known from at least 37 streams but is currently
restricted to no more than 12 isolated populations. Current status
information for most of the 12 populations deemed to be extant is
available from recent periodic sampling efforts (sometimes annually)
and other field studies, particularly in the upper Tennessee River
system. Some populations in the Cumberland River system have had recent
surveys as well (e.g., Wolf, Little Rivers; Little South Fork; Horse
Lick, Buck Creeks). Populations in Buck Creek, Little South Fork, Horse
Lick Creek, Powell River, and North Fork Holston River have clearly
declined over the past two decades. Based on recent information, the
overall population of the fluted kidneyshell is declining rangewide and
the species remains in large numbers and is clearly viable in just the
Clinch River/Copper Creek, although smaller, viable populations remain
(e.g., Wolf, Little, North Fork Holston Rivers; Rock Creek). Most other
populations are of questionable or limited viability, with some on the
verge of extirpation (e.g., Powell River; Little South Fork; Horse
Lick, Buck, Indian Creeks). Newly reintroduced populations in the
Nolichucky and Duck Rivers will hopefully begin to reverse the downward
population trend of this species. The threats are high in magnitude
since all populations of this species are severely affected by numerous
threats (impoundments, sedimentation, small population size, [[Page 69040]]
isolation of populations, gravel mining, municipal pollutants,
agricultural runoff, nutrient enrichment, and coal processing
pollution) which results in mortality and/or reduced reproductive
output. Since the threats are ongoing, they are imminent. Therefore, to
help ensure consistency in the application of our listing priority
process, we changed the LPN from a 5 to a 2 to reflect that the threats are imminent and high in magnitude.
Snails
Black mudalia (Elimia melanoides)The black mudalia is a small species of aquatic snail found clinging to clean gravel, cobble, boulders and/or logs in flowing water on shoals and riffles. The historical habitat of the black mudalia included much of the upper Black Warrior River drainage above the Fall Line at Tuscaloosa, Alabama. The species has been extirpated from more than 80 percent of that range through the construction of dams and impoundments, sedimentation, and nonpoint source pollution from land surface runoff. Populations that may have avoided impoundment apparently disappeared due to historical pollution events and/or natural catastrophic events. However, after being considered extinct for two decades, the black mudalia was rediscovered in a small portion of its historical range in the Black Warrior drainage. Discovery of surviving populations in shoals of five streams in the upper Black Warrior River and high densities reported at Blackburn Fork reduce the magnitude of the threats from high to moderate. However, all known populations are currently affected by point and/or nonpoint source pollution; human land uses, including cattle grazing, row crops, timber, chicken farms, and home construction are currently causing sedimentation and eutrophication (reduction of oxygen in the water) of black mudalia habitats. Thus, based on ongoing threats that we now consider to be moderate in magnitude, we changed the LPN from 2 to 8 for the black mudalia.
Huachuca springsnail (Pyrgulopsis thompsoni)The following summary is based on information from our files. No new information was provided in the petition received on May 11, 2004. The Huachuca springsnail inhabits 13 springs and ci[eacute]negas at elevations of 4,500 to 7,200 feet in southeastern Arizona (11 sites) and adjacent portions of Sonora, Mexico (2 sites). The springsnail is typically found in the shallower areas of springs or cienegas, often in rocky seeps at the spring source. Ongoing threats include habitat modification, wildfire, cattle grazing, and groundwater pumping. Prior communication with personnel from Fort Huachuca indicated they were in the process of evaluating the status of this species on Department of Defense lands and developing conservation strategies; this may result in a reduction or elimination of threats in the future. Because we determined that the proportion of the range subjected to various threats is smaller than we previously determined, the threats are moderate in magnitude. In addition, although there is no actual change in threats over the past year, modification of the spring habitat, wildfire, cattle grazing, and groundwater pumping are ongoing or imminent threats. Therefore, to help ensure consistency in the application of our listing priority process, we changed the LPN from a 5 to an 8 to reflect that the threats are imminent but are moderate in magnitude.
Page springsnail (Pyrgulopsis morrisoni)The following summary is based on information from our files. No new information was provided in the petition received on May 11, 2004. The Page springsnail is known to exist only within a complex of springs located within an approximately 1.5kilometer (0.93mile) stretch along the west side of Oak Creek around the community of Page Springs, Yavapai County, Arizona. Many of the springs where the springsnail occurs have been subjected to some level of modification for domestic, agricultural, ranching, fish hatchery, and recreational activities. Arizona Game and Fish Department management plans for the Bubbling Ponds and Page Springs fish hatcheries include commitments to replace lost habitat and to monitor remaining populations of invertebrates such as the Page springsnail. The Arizona Game and Fish Department and the Service have made significant progress on development of a candidate conservation agreement, but the effectiveness of planned and implemented actions has not been demonstrated. Based on recent survey data, it appears that the Page springsnail is abundant within natural habitats and persists in modified habitats, albeit at reduced densities. The magnitude of threats is considered high because limited distribution of this narrow endemic makes any detrimental effects from threats likely to result in extirpation or extinction. The immediacy of the threat of groundwater withdrawal is uncertain due to conflicting information that suggests it may be either imminent or not. However, overall, the threats are imminent because the majority of them are currently occurring. Although there is no actual change in threats over the past year, modification of the spring habitat for this species is an ongoing or imminent threat. Therefore, to help ensure consistency in the application of our listing priority process, we changed the LPN from a 5 to a 2 to reflect that the threats are imminent.
Insects
Dakota skipper (Hesperia dacotae)The following summary is based on information contained in our files, including information from the petition we received on May 12, 2003. The Dakota skipper is a small to midsized butterfly that inhabits highquality tallgrass and mixed grass prairie in Minnesota, North Dakota, South Dakota, and the provinces of Manitoba and Saskatchewan in Canada. The species is presumed to be extirpated from Iowa and Illinois and from many sites within occupied States.
The species is threatened by conversion of its native prairie
habitat for agricultural purposes, overgrazing, invasive species,
gravel mining, inbreeding, population isolation, and, in some cases,
prescribed fire. Prairie succeeds to shrubland or forest without
periodic fire, grazing, or mowing; thus, the species is also threatened
at sites where such disturbances are not applied. We, other agencies,
and private organizations (e.g., The Nature Conservancy) protect and
manage some Dakota skipper sites. Although proper management is always
necessary to ensure its persistence, even at protected sites, it is
secure at some sites owned by these entities. The species is also
secure at some sites where private landowners manage native prairie in
ways that conserve Dakota skipper. Recent surveys in at least parts of
the species' range have led us to revise our view of the imminence of
threats to Dakota skipper. In January 2007, for example, Minnesota
Department of Natural Resources proposed revising the status of Dakota
skipper in the state from threatened to endangered because it ``appears
to be rapidly disappearing from remnant habitat.'' In addition,
approximately half of the inhabited sites are privately owned with
little or no protection. Ongoing threats on these sites include
invasive species, overgrazing, and herbicide applications. A few
private sites are protected from conversion by easements, but these do
not prevent adverse effects from overgrazing. The threats are such that
the species warrants listing; the threats are moderate in magnitude and, based on
[[Page 69041]]
the above new information, are imminent. Therefore, we changed the
listing priority number from an 11 to an 8 for the Dakota skipper to
reflect the increase in immediacy of threats to remnant habitat, particularly on private lands.
Coral Pink Sand Dunes tiger beetle (Cicindela albissima)The Coral Pink Sand Dunes tiger beetle occurs only at the Coral Pink Sand Dunes, approximately 7 miles west of Kanab, Kane County, in southcentral Utah. It is restricted to a small part of the dune field, situated at an elevation of about 1,820 m (6,000 ft). The beetle's habitat is being adversely affected by ongoing recreational offroad vehicle use that is destroying and degrading the beetle's habitat, especially the interdunal swales used by the larvae. The continued survival of the beetle depends on the preservation of its habitat. The two agencies that manage the dune field, the Utah Department of Parks and Recreation and the Bureau of Land Management, have restricted recreational off road vehicle use in some areas, which reduces impacts. However, the protected areas may not be of sufficient size to enable the population to increase in size. The beetle's population is also vulnerable to overcollecting by professional and hobby tigerbeetle collectors. Because the taxon was recently elevated to a full species based on genetic research, we changed the listing priority from a 9 to an 8. The imminence and magnitude of the threats remain the same (imminent and moderate to low magnitude).
Stephan's riffle beetle (Heterelmis stephani)The following summary is based on information from our files. No new information was provided in the petition we received on May 11, 2004. The Stephan's riffle beetle is an endemic riffle beetle found in limited spring environments within the Santa Rita Mountains, Pima County, Arizona. The beetle is known from Bog Spring and Sylvester Spring in Madera Canyon, within the Coronado National Forest. These springs are typical isolated, midelevation, permanently saturated, springfed aquatic climax communities commonly referred to as ci[eacute]negas. Threats are largely from habitat modification (from recreational activities in the springs and changes in water chemistry due to catastrophic natural disasters such as fires or floods); we consider them to be of moderate to low magnitude due to the lack of focused studies to evaluate the permanence of threats or the likelihood of persistence of the species in areas that are unaffected. Furthermore, because the threats are currently occurring, they are best characterized as imminent. Due to moderate to low magnitude of imminent threats, we changed the LPN from a 5 to an 8 for Stephan's riffle beetle.
Crustaceans
Typhlatya monae (troglobitic groundwater shrimp)Typhlatya monae is a subterranean small shrimp known from Puerto Rico, Barbuda, and Dominican Republic. It is classified as a troglobite, or obligatory cave organism, of which its most extraordinary feature is the reduction or loss of vision and pigmentation. It feeds on organic waste material and debris, such as bat guano.
Little is known concerning the status of Typhlatya monae in either Barbuda or Dominican Republic. Although in Puerto Rico this species was previously found at Mona Island, currently Typhlatya monae is known from only three caves within the Gu[aacute]nica Commonwealth Forest in the municipalities of Gu[aacute]nica, Yauco, and Guayanilla. However, the species may still be found in the reef deposit aquifers in Mona Island that have not yet been surveyed. In 1995, close to 2,000 individuals were estimated; over 95 percent of these were observed in only one cave. Although no systematic censuses have been conducted since 1995, we have recently documented the presence of the species in all three caves and obtained information regarding another cave in which the species may occur from Puerto Rico Commonwealth Forest personnel.
Changes in groundwater quality, collection of rare animals, predation, limited distribution of the species, limited availability of appropriate habitat (i.e., underground aquifers within cave formations), potential reduction of food sources (e.g., mortality or reduction in bat populations), and low population numbers potentially threaten populations of Typhlatya monae. However, because the known range of Typhlatya monae is within protected lands, and because we have received new information of known management activities within the Gu[aacute]nica Commonwealth Forest or Mona Island (activities are managed such that some of the threats to this species no longer exist; e.g. the caves are closed to visitors), we now consider the magnitude of the remaining threats (possible extraction of groundwater in Mona and vulnerability to catastrophic events) moderate to low. Therefore, we changed the LPN from a 5 to an 11 for this species.
Flowering plants
Abronia alpina (Ramshaw Meadows sandverbena)Abronia alpina is a small perennial herb, 2.5 to 15.2 centimeters (1 to 6 inches) across which forms compact mats with lavenderpink, trumpetshaped, and generally fragment flowers. Abronia alpina is known from one main population center in Ramshaw Meadow on the Kern Plateau of the Sierra Nevada, California, and from one subpopulation found in adjacent Templeton Meadow. The total estimated area occupied is approximately 6 hectares (15 acres). The population fluctuates from year to year without any clear trends. Population estimates from 19851994 range from a low of 69,652 plants in 1986 to 132,215 plants in 1987. Surveys conducted since 1994 indicate that no significant changes have occurred in population size or location, although, the 2003 survey showed population numbers to be at the low end of the range. The population was last monitored in 2006.
The threats currently facing Abronia alpina include natural and
human habitat alteration, hydrologic changes to the water table, and
recreational use within meadow habitats. Lodgepole pine encroachment
has altered the meadow and becoming established within A. alpina
habitat. Lodgepole pine encroachment may alter soil characteristics by
increasing organic matter levels, decreasing porosity, and moderating
diurnal temperature fluctuations thus reducing the competitive ability
of A. alpina to persist in an environment more hospitable to other
plant species. The Ramshaw Meadow ecosystem is subject to potential
alteration by lowering of the water table due to downcutting of the
South Fork of the Kern River (SFKR). The SFKR flows through Ramshaw
Meadow, at times coming within 15 m (50 ft) of A. alpina habitat,
particularly in the vicinity of five subpopulations. The habitat
occupied by A. alpina directly borders the meadow system supported by
the SFKR. Drying out of the meadow system could potentially affect A.
alpina pollinators and/or seed dispersal agents. Established hiker,
packstock, and cattle trails pass through A. alpina subpopulations. Two
main hiker trails pass through Ramshaw Meadow, but were rerouted out of
A. alpina subpopulations where feasible, in 1988 and 1997. Remnants of
cattle trails that pass through subpopulations in several places
receive occasional incidental use by horses and sometimes hikers.
Cattle use, however, currently, is not a threat due to the 2001 implementation of a tenyear
[[Page 69042]]
moratorium on the Templeton allotment which prohibits cattle from all
A. alpina locations. In 2007, the U.S. Forest Service in cooperation
with the Service drafted a Conservation Agreement for A. alpina that
would provide protective measures via increased management of
recreation in the area, habitat management, and research on A. alpina.
Approval and finalization of this Agreement is anticipated in Fiscal
Year 2008. The Service is funding studies to determine appropriate
conservation measures. As a result of rerouting hiking trails,
curtailing grazing, and development of a Conservation Agreement between
the U.S. Forest Service and the Service the threats facing Abronia
alpina have been reduced. Because the population is stable and the
threats have been reduced, we changed the LPN for A. alpina from an 8
to an 11, reflecting nonimminent threats that are moderate to low in magnitude.
Bidens campylotheca ssp. waihoiensis (Kookoolau)Kookoolau is an erect, perennial found in wet AcaciaMetrosideros (koaohia) forest on Maui, Hawaii. Bidens campylotheca ssp. waihoiensis is known from 1 and possibly 2 populations, 1 of 200 individuals, and the second of possibly as many as 300 individuals. It is threatened by feral pigs and cattle, which eat this plant and degrade and destroy habitat, and by nonnative plants that outcompete and displace it. Conservation measures such as strategic fences and control of nonnative plants benefit the plants in Kipahulu Valley; however, the individuals in Waihoi Valley are still affected by these threats. Therefore, to reflect the fact that the threats are ongoing, we have changed the LPN for this species from a 6 to a 3.
Chamaecrista lineata var. keyensis (Big Pine partridge pea)This pea is endemic to the lower Florida Keys, and restricted to pine rocklands, hardwood hammock edges, and roadsides and firebreaks within these ecosystems. Historically, it was known from Big Pine, No Name, Ramrod, and Cudjoe Keys (Monroe County, Florida). It presently occurs on Big Pine, plus two very small populations found on Cudjoe and lower Sugarloaf Keys in 2005. It is fairly well distributed in Big Pine Key pine rocklands, which encompass approximately 580 hectares (1,433 acres). Roughly 90 percent of its current range is within the Service's National Key Deer Refuge. In late 2005, it occurred within 37.2 percent of 541 plots sampled throughout the publicly owned pine rocklands on Big Pine Key. Frequency of occurrence was twice as great and density over 3 times greater in the less fragmented, more fireprone northern portion of Big Pine Key than the southern part. Pine rockland communities are maintained by relatively frequent fires. In the absence of fire, shrubs and trees encroach on pine rockland and the pea is eventually shaded out. The National Key Deer Refuge (NKDR) has a prescribed fire program, though with many constraints on implementing fire. Absence of fire is the greatest of the shortterm and deterministic threats.
Hurricanes are also a threat. Hurricane Wilma (October 2005) resulted in a storm surge that covered most of Big Pine Key with sea water. In plots sampled after Wilma, frequency of occurrence decreased to less than a third and density decreased to less than half that found in plots sampled before Wilma.
The magnitude of threats to the Big Pine partridge pea is moderate. Partridge pea has a very limited distribution that is somewhat fragmented and fire limitation, salt water storm surges (direct mortality, as well as slash pine mortality, associated with hurricanes), and pollinator limitation, constitute significant threats. Additionally, threats from storm surges associated with hurricanes are exacerbated by sea level rise. Big Pine partridge pea exists as one relatively large population (possibly fragmented into a metapopulation) on Big Pine Key and two very small, isolated populations on two other keys. However, population size is on the order of several hundred thousand, and the majority occurs on the NKDR. Over the long run, partridge pea receives protective measures only on NKDR and the Terrestris Preserve. The immediacy of threats is imminent as the probability of intense hurricanes has increased in recent years, and increasingly sea levels have exacerbated the threat. Additionally, storm surges have complicated efforts to conduct prescribed fires. If the frequency of prescribed fire does not increase, the imminence of threats due to fire suppression will continue to increase. Because the threats are moderate rather than high in magnitude due to some protection from threats provided by the NKDR and Terrestris Preserve, we changed the LPN from a 6 to a 9 for the Big Pine partridge pea.
Chamaesyce deltoidea ssp. serpyllum (Wedge spurge)New survey results were obtained in March 2006. Wedge spurge is a small, prostrate herb. It has always been restricted to Big Pine Key in Monroe County, Florida. Most of the range falls within the National Key Deer Refuge. It is restricted to pinelands on limestone rock (pine rockland), at sites with exposed rock or gravel, low understory cover, and low hardwood density. Pine rocklands encompass approximately 580 hectares (1,433 acres) on Big Pine Key. It is not widely dispersed within the limited range. In late 2005, it occurred within 7.4 percent of 541 plots sampled throughout the publicly owned pine rocklands on Big Pine Key. Hurricane Wilma (October 2005) resulted in a storm surge that covered most of Big Pine Key with seawater. Before and after Wilma, it occurred in 9.3 of 332 sample plots and 4.3 percent of 209 sample plots, respectively, and density decreased significantly within plots. Occupied plots had become restricted to the higher, middle portion of Big Pine Key. In the absence of fire, shrubs and trees encroach on pine rockland and spurge is eventually shaded out.
The magnitude of threats to the wedge spurge is moderate. Wedge spurge has a narrow distribution composed of few occurrences, and threats result from lack of fire, hurricanes, sea level rise, and invasive exotic plants. Additionally, threats from storm surges associated with hurricanes are exacerbated by sealevel rise. Wedge spurge exists essentially as a single (fragmented) population on Big Pine Key, which over the long run is protected only on NKDR and the Terrestris Preserve. However, population size is on the order of several hundred thousand, and the majority occurs on the NKDR. The National Key Deer Refuge has a prescribed fire program, though with many constraints on implementing fire.
The threats to the wedge spurge are imminent. The best available information indicates that this plant is intrinsically vulnerable to extinction because it is a narrow endemic. Moreover, the threats of hurricanes and shading due to lack of fire are ongoing. However, because the threats are moderate rather than high in magnitude due to some protection from threats provided by the NKDR and Terrestris Preserve, we changed the LPN from a 6 to a 9 for the wedge spurge.
Cordia rupicola (no common name)Cordia rupicola, a small shrub,
has been described from southwestern Puerto Rico (Pe[ntilde]uelas and
Gu[aacute]nica), Vieques Island, and Anegada Island (British Virgin
Islands). Cordia rupicola is restricted to subtropical dry forest life
zone overlying a limestone substrate. At present time, less than 20
individuals of C. rupicola are currently known from four sites in
Puerto Rico; only a few individuals are located in protected lands managed for conservation by the
[[Page 69043]]
Puerto Rico Department of Natural and Environmental Resources or the
Service. The area that contains 83 percent of the known population is
located in a privatelyowned property and is threatened by habitat
destruction or modification. While the population on Anegada Island is
currently stable, this population is threatened by potential
residential and commercial development. Both populations are also
vulnerable to natural (e.g., hurricanes) or manmade (e.g., human
induced fires) threats. All sites are located in a xeric environment
vulnerable to humaninduced fires which could destroy entire
populations. For these reasons, the magnitude of the current threats is
high. While hurricanes and fire do occur, the rate of occurrence is
such that they do not pose an imminent threat. The threats this species
faces are ones that will arise in the future if conservation measures
are not implemented and longterm impacts are not averted. For these
reasons, the threats to the species as a whole are nonimminent, and
therefore, we changed the LPN from a 2 to a 5 for this species.
Dalea carthagenensis floridana (Florida prairieclover)Dalea carthagenensis floridana occurs in Big Cypress National Preserve in Monroe and Collier Counties, Florida. It is also known from small populations in MiamiDade County. There are a total of nine extant occurrences, most of which are on conservation land. Existing occurrences are extremely small and may not be viable, especially those in MiamiDade County. Remaining habitats are fragmented. This plant is threatened by habitat loss and habitat degradation due to fire suppression, the di
FOR FURTHER INFORMATION CONTACT
The Endangered Species Coordinator(s) in the appropriate Regional Office(s) or Chris Nolin, Chief, Division of Conservation and Classification (telephone 7033582171; facsimile 7033581735). Persons who use a telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 800877 8339.