[Federal Register Volume 71, Number 188 (Thursday, September 28, 2006)]
[Proposed Rules]
[Pages 56932-56936]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-15874]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17


Endangered and Threatened Wildlife and Plants; 90-Day Finding on 
a Petition To List the Anacapa Deer Mouse as Threatened or Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 90-day petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
90-day finding on a petition to list the Anacapa deer mouse (Peromyscus 
maniculatus anacapae) as threatened or endangered under the Endangered 
Species Act of 1973, as amended. We find the petition does not present 
substantial information indicating that listing the Anacapa deer mouse 
may be warranted. Therefore, we are not initiating a status review in 
response to this petition. We ask the public to submit to us any new 
information that becomes available concerning the status of the 
subspecies or threats to it or its habitat at any time. This 
information will help us monitor and encourage the conservation of the 
subspecies.

DATES: The finding announced in this document was made on September 28, 
2006.

ADDRESSES: The complete supporting file for this finding is available 
for public inspection, by appointment, during normal business hours at 
the Ventura Fish and Wildlife Office, U.S. Fish and Wildlife Service, 
2493 Portola Road, Suite B, Ventura, California 93003. Submit new 
information, materials, comments, or questions concerning this 
subspecies to us at the above address.

FOR FURTHER INFORMATION CONTACT: Diane Noda, Field Supervisor, Ventura 
Fish and Wildlife Office (see ADDRESSES section above), by telephone at 
805/644-1766, or by facsimile at 805/644-3958.

SUPPLEMENTARY INFORMATION: 

[[Page 56933]]

Background

    Section 4(b)(3)(A) of the Endangered Species Act of 1973, as 
amended (Act) (16 U.S.C. 1531 et seq.), requires that we make a finding 
on whether a petition to list, delist, or reclassify a species presents 
substantial scientific or commercial information to indicate that the 
petitioned action may be warranted. We are to base this finding on 
information provided in the petition, supporting information submitted 
with the petition, and information otherwise available in our files at 
the time we make the determination. To the maximum extent practicable, 
we are to make this finding within 90 days of our receipt of the 
petition, and publish our notice of this finding promptly in the 
Federal Register.
    Our standard for substantial information within the Code of Federal 
Regulations (CFR) with regard to a 90-day petition finding is ``that 
amount of information that would lead a reasonable person to believe 
that the measure proposed in the petition may be warranted'' (50 CFR 
424.14(b)). If we find that substantial information was presented, we 
are required to promptly commence a review of the status of the 
species.
    In making this finding, we relied on information provided by the 
petitioners and evaluated that information in accordance with 50 CFR 
424.14(b). Our process of coming to a 90-day finding under section 
4(b)(3)(A) of the Act and section 424.14(b) of our regulations is 
limited to a determination of whether the information in the petition 
meets the ``substantial information'' threshold.
    On November 8, 2002, we received a formal petition, dated October 
29, 2002, from the Channel Islands Animal Protection Association and 
The Fund for Animals. The petition requested that the Anacapa deer 
mouse (Peromyscus maniculatus anacapae) be emergency listed as 
threatened or endangered in accordance with section 4 of the Act. The 
petition clearly identified itself as such and contained the names, 
addresses, and signatures of the petitioning organizations' 
representatives. In response to the petitioner's requests, we sent a 
letter to the petitioners dated March 10, 2003, explaining that we 
would not be able to address their petition until fiscal year 2004. The 
reason for this delay was that responding to existing court orders and 
settlement agreements for other listing actions required nearly all of 
our listing funding. We also concluded in our March 10, 2003, letter 
that emergency listing of the Anacapa deer mouse was not indicated. 
Delays in responding to the petition continued due to the high priority 
of responding to court orders and settlement agreements, until funding 
recently became available to respond to this petition.

Subspecies Information

    The deer mouse (Peromyscus maniculatus) is an abundant member of 
the rodent family Muridae and is widespread throughout much of North 
America except for the southeastern United States and some parts of 
Mexico. Adults range in size from 119 to 222 millimeters (5 to 9 
inches) and weigh from 10 to 24 grams (0.4 to 0.8 ounces). Deer mice 
range from grayish to reddish-brown with white underparts, and the tail 
is covered with fine hairs and is sharply bicolored (dark above, white 
below) (Bunker 2001, pp. 1-6).
    Deer mice may breed year-round, but breeding is more frequent 
during the warmer months when they may produce a litter every 3 to 4 
weeks. Gestation ranges from 22 to 31 days depending on whether or not 
the female is lactating; typical litter size is 4 to 6. Deer mice are 
primarily nocturnal and have keen senses of vision, hearing, touch, and 
smell. Nests may be located in trees, stumps, wood piles, or buildings 
and may be constructed of leaves, grasses, shredded bark, moss, paper, 
cloth, or any other available material. The home ranges of deer mice 
vary from 242 to 3,000 square meters (0.06 to 0.74 acres (ac)). Home 
ranges of males are larger than females and show more overlap. Females 
defend their territories more than males; therefore their territories 
overlap less. Deer mice are omnivorous and eat a wide variety of plant 
and animal material including seeds, fruit, flowers, nuts, insects, and 
other invertebrates. Deer mice are themselves preyed upon by a variety 
of predators, including snakes, birds of prey, and mammalian predators.
    Deer mice are found on all eight of the Channel Islands (from north 
to south: San Miguel, Santa Rosa, Santa Cruz, Anacapa, Santa Barbara, 
San Nicolas, Santa Catalina, and San Clemente), and are classified as 
separate subspecies on each island (Pergams and Ashley 2000, p. 278). 
Deer mice on the Channel Islands are generally darker and somewhat 
larger than those on the mainland, with the Anacapa deer mouse being 
one of the larger of the Channel Island deer mice (Pergams and Ashley 
2000, p. 279). Channel Island deer mice have been variously described 
since 1897 (Mearns 1897, pp. 719-724), when they were first identified; 
however, von Bloeker (1940, pp. 172-174; 1941, pp. 161-162) first 
described those from Anacapa Island as a separate subspecies. As 
indicated by its name, the Anacapa deer mouse is the endemic subspecies 
to Anacapa Island.
    Anacapa Island is one of the five islands that comprise the Channel 
Islands National Park and is the closest to the mainland, approximately 
15 kilometers (km) (9 miles (mi)) from the nearest point along the 
coast. Anacapa Island is approximately 8 km (5 mi) long and is 
comprised of three islets, East Anacapa, Middle Anacapa, and West 
Anacapa. Anacapa deer mice are known to occur on all three of the 
islets. The three islets are in close proximity to each other (less 
than 150 meters (450 feet)), and the total area of the three islets 
combined is approximately 290 hectares (717 ac). The rugged terrain of 
the island is characterized by steep cliffs and canyons, which provide 
limited access to the island. Access is also limited by National Park 
Service (NPS) regulations and during the nesting season of the 
endangered brown pelican (Pelicanus occidentalis). Vegetation on the 
island consists of mainly grasslands and scrub vegetation and is 
heavily influenced by nonnative species, including several nonnative 
grasses and iceplant (Malephora crocea).
    Although minor genetic differences occur between the deer mice on 
the three islets, all of them are classified as the same subspecies 
(Peromyscus maniculatus anacapae) based on both similar genetic and 
morphological characteristics (Pergams and Ashley 2000, p. 286). 
Pergams and Ashley (2000, p. 286) concluded that genetic similarities 
between the deer mice on the three islets indicates some migration 
between the islets occurs on a regular basis. As noted by Pergams and 
Ashley (2000, p. 286), deer mice were thought to be very rare on East 
Anacapa since 1966, and possibly extinct since about 1981; they were 
again found on East Anacapa in 1997. The genetic research of Pergams 
and Ashley (2000, p. 286) suggests either that the deer mice on East 
Anacapa were never completely extirpated or that East Anacapa was 
recolonized from one of the other islets.
    Although not listed as either threatened or endangered by the State 
of California, the California Department of Fish and Game (CDFG) has 
listed the Anacapa deer mouse as a Species of Special Concern.

Threats Analysis

    Section 4 of the Act and its implementing regulations (50 CFR part 
424) set forth the procedures for adding species to the Federal List of 
Endangered and Threatened Wildlife and Plants. A species may be 
determined to be an endangered or

[[Page 56934]]

threatened species due to one or more of the five factors described in 
section 4(a)(1) of the Act: (A) Present or threatened destruction, 
modification, or curtailment of habitat or range; (B) overutilization 
for commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) inadequacy of existing regulatory mechanisms; 
or (E) other natural or manmade factors affecting its continued 
existence. In making this finding, we evaluated whether threats to the 
Anacapa deer mouse presented in the petition and other information 
available in our files at the time of the petition review may pose a 
concern with respect to the subspecies' survival. Our evaluation of 
these threats is presented below. The petition did not address the five 
listing factors directly and did not organize potential threats to the 
Anacapa deer mouse by listing factor. In the discussion below, we have 
placed the threats listed in the petition under the most appropriate 
listing factor.

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range

    The petition did not list any threats to the habitat of the Anacapa 
deer mouse. We are not aware of any scientific or commercial 
information to indicate there are any present or future threats to the 
habitat of the Anacapa deer mouse.

B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    The petition did not provide information or list any threats to the 
Anacapa deer mouse from overutilization for commercial, recreational, 
scientific, or educational purposes. We are not aware of any scientific 
or commercial information that would indicate there are any past, 
present, or future threats to the Anacapa deer mouse from 
overutilization for commercial, recreational, scientific, or 
educational purposes.

C. Disease and Predation

    The petition did not list any threats to the Anacapa deer mouse 
from disease or predation. We are not aware of any scientific or 
commercial information that would indicate disease or predation poses a 
current threat to the Anacapa deer mouse. However, prior to the black 
rat (Rattus rattus) eradication program on Anacapa Island, information 
from the NPS (2003, p. 1) indicated that one of the most serious 
threats to the Anacapa deer mouse was the presence of the introduced 
black rat on the island. Black rats were likely first introduced to the 
island as a result of shipwrecks (NPS 2006, p. 1). Black rats are known 
to prey on Anacapa deer mice, and also compete with them for food and 
exclude them from certain habitats (NPS 2003, p. 1). Black rats may 
also have been responsible for the disappearance of deer mice on East 
Anacapa from at least 1981, until they were again found in 1997 
(Pergrams and Ashley 2000, p. 286; NPS 2003, p. 1). As of post-
eradication monitoring in 2005, black rats are no longer found on 
Anacapa Island (Howald et al. 2005, p. 305). Therefore, black rats are 
not a threat to the Anacapa deer mouse at the present time.

D. The Inadequacy of Existing Regulatory Mechanisms

Information Provided in the Petition
    The petitioners were concerned that the NPS project to eradicate 
black rats from Anacapa Island with poison would result in the 
extinction of the Anacapa deer mouse, and that the NPS mitigation plan 
for the mouse was insufficient. Specifically, the petition states that, 
``The NPS project poisoning Anacapa Island represents the premeditated 
man-made destruction of a large percentage of an already jeopardized 
population. This demonstrates that the listing by California Fish and 
Game [as a Species of Special Concern] insufficiently protects the rare 
Anacapa Deer Mouse, and that Federal listing under the Endangered 
Species Act is necessary.''
Analysis of Information Provided in the Petition and Information 
Available to Us at the Time of Petition Review
    The CDFG Species of Special Concern designation does not result in 
additional regulatory requirements with regard to Federal activities 
such as the NPS's black rat eradication activities, but is intended to 
result in special consideration for these animals by CDFG, land 
managers, consulting biologists, and others, and focus attention on the 
species to avert the need for listing under Federal and State 
endangered species laws. For example, the CDFG was one of the parties 
involved in formulating the basic plan for eradicating black rats from 
Anacapa Island and approving the funding for the Anacapa Island black 
rat eradication program (American Trader Trustee Council 2001, pp. 20-
23). As a participant, the CDFG recognized both that the black rat was 
a threat to the Anacapa deer mouse (American Trader Trustee Council 
2001, p. 21) and that eradicating black rats was likely to have a 
positive benefit to the Anacapa deer mouse in the long term (American 
Trader Trustee Council 2001, p. 22). However, it was also recognized 
that the poisoning of the rats would also poison other species, 
including the Anacapa deer mouse, but that the overall benefit to the 
island ecology would outweigh the short-term effects (American Trader 
Trustee Council 2001, p. 22). The importance of the Anacapa deer mouse 
was further recognized in that the NPS developed (NPS 2000, p. 17) and 
successfully carried out (Howald et al. 2005, p. 305) a plan for 
ensuring the protection of the mouse (for details see E. Other Natural 
or Manmade Factors Affecting Continued Existence below). Therefore, the 
status of the Anacapa deer mouse as a California Species of Special 
Concern played an important role in ensuring the protection of this 
subspecies during the planning stages of the black rat eradication 
process. We also note that the petition was prepared prior to the final 
black rat eradication activities that were completed in November 2002.
    Several Federal laws pertaining to national parks act indirectly 
protect the Anacapa deer mouse as one of many sensitive park resources. 
As noted above, Anacapa Island is part of the Channel Islands National 
Park (CINP). CINP was established in 1980, by Public Law (Pub. L.) 96-
199, ``* * * to protect the nationally significant natural, scenic, 
wildlife, marine, ecological, archaeological, cultural, and scientific 
values of the Channel Islands in the State of California.'' CINP is 
also affected by other laws pertaining to national parks. The NPS 
Organic Act of 1916 (16 U.S.C. 1) established the National Park Service 
and mandated that it ``shall promote and regulate the use of the 
Federal areas known as national parks, monuments, and reservations * * 
* by such means and measures as conform to the fundamental purpose of 
the said parks, monuments, and reservations, which purpose is to 
conserve the scenery and the natural and historic objects and the wild 
life therein and to provide for the enjoyment of the same in such 
manner and by such means as will leave them unimpaired for the 
enjoyment of future generations.'' Redwood National Park Expansion Act 
(Pub. L. 95-250) of 1978 directs that within the National Park System, 
``authorization of activities shall be construed and the protection, 
management, administration of these areas shall be conducted in light 
of the high public value and integrity of the National Park System and 
shall not be exercised in derogation of the values and purposes for 
which these various areas have been established.'' National Parks 
Omnibus Management Act of

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1998 (Pub. L. 105-391) directs ``the National Park Service to provide 
state-of-the-art management, protection, and interpretation of and 
research on the resources of the National Park system.'' This law also 
stipulates that ``the trend in the condition of resources of the 
National Park System shall be a significant factor in the annual 
performance evaluation of each superintendent of a unit of the National 
Park System.''
    The National Environmental Policy Act of 1969 (42 U.S.C. 4321 et 
seq.), as amended (NEPA), requires all Federal agencies to formally 
document and publicly disclose the environmental impacts of their 
actions and management decisions. NEPA documentation is provided in 
either an environmental impact statement (EIS), an environmental 
assessment, or a categorical exclusion, and may be subject to 
administrative or judicial appeal. The NPS considered the impacts of 
black rat eradication on the Anacapa deer mouse in their EIS on the 
Anacapa Island Restoration Project (NPS 2000, p. 1-139) and included a 
mitigation plan for the Anacapa deer mouse (NPS 2000, p. 17).
    Therefore, the State and Federal regulations listed above acted to 
ensure that the future of the Anacapa deer mouse was considered and 
planned for during the black rat eradication project, and we find that 
the petition, supporting information, and information readily available 
to the Service does not present substantial information for this factor 
indicating that the petitioned action may be warranted.

E. Other Natural or Manmade Factors Affecting Continued Existence

Information Provided in the Petition
    One of the concerns raised in the petition is the fact that the 
Anacapa deer mouse is restricted to a single island and therefore is 
vulnerable to extinction. However, the principal threat to the Anacapa 
deer mouse presented in the petition was the detrimental effects on the 
Anacapa deer mouse from the NPS project to eradicate black rats from 
the island. The eradication of black rats on Anacapa Island, which was 
initiated in 2001 as part of the Anacapa Island Restoration Project 
(NPS 2000, pp. 1-139), involved the aerial application of bait poisoned 
with the rodenticide brodifacoum. The petition stated that the 
application of brodifacoum to kill black rats would also kill all of 
the Anacapa deer mice on the island that had not been brought into 
captivity. Furthermore, the petitioners concluded that the NPS plan for 
ensuring the survival of the Anacapa deer mouse was insufficient to 
guarantee success. The petitioners believed that either the NPS would 
not capture enough mice to ensure that there would be a sufficient 
number available to repopulate the island or the mouse population would 
likely undergo a drastic crash while in captivity, which would again 
result in too few to repopulate the island. The petitioners stated 
that, although the geneticist for the NPS recommended 333 deer mice be 
captured on each of the three islets, the NPS only captured 175 on East 
Anacapa. The petitioners believed a crash in the captive population was 
likely to result from either the physical and psychological stresses of 
capture and confinement or from a rogue pathogen that would rapidly 
spread throughout the captive population or from a combination of these 
two reasons. Another issue the petitioners raised was the possibility 
that holding Anacapa deer mice in captivity could induce a genetic 
change that would alter the evolutionary process of the Anacapa deer 
mouse and that such a change could occur within just a few reproductive 
cycles. The petitioners believed that a genetic change in the captive 
Anacapa deer mice could result from the stress of captivity, limited 
breeding selection, radical environmental changes, or an unknown 
influence. They also believed that this genetic change could be 
detrimental to the survival of the Anacapa deer mice once they were 
released back to Anacapa Island. The petitioners also stated that the 
captive Anacapa deer mice must be released at a specific point in their 
population cycle to maximize chances of survival. Finally, the 
petitioners believed that the poison bait could remain in the 
environment for decades and threaten any Anacapa deer mice released.
Analysis of Information Provided in the Petition and Information 
Available to Us at the Time of Petition Review
    We agree with the petitioners that species, such as the Anacapa 
deer mouse, that inhabit islands, especially small islands, are 
vulnerable to extinction. However, over the last several hundred years, 
most island extinctions have resulted from human-related threats, 
especially introduced species such as the black rat (for a review of 
island extinctions, see Chapter 20 in Bryant 2005, pp. 1-19). We do not 
base a decision to list a species as endangered or threatened because 
it is restricted to an island or is simply rare, but because its 
existence is threatened by one or more of the five listing factors. 
Recognizing the damage black rats were doing to nesting seabirds and 
the environment of Anacapa Island, the NPS developed and carried out a 
project to eliminate rats from the island as part of their goal to 
restore the ecology of the island (NPS 2000, pp. 1-139). Predation by 
black rats was probably the main cause for the long-term decline in the 
breeding populations of Xantus's murrelets (Synthliboramphus 
hypoleucus) and other seabirds observed on Anacapa Island (McChesney et 
al. 2000, p. 2). The NPS stated that maintaining the island as rat-free 
would improve seabird nesting habitat and aid in the recovery of 
crevice-nesting seabirds, such as the Xantus's murrelet and ashy storm-
petrel (Oceanodroma homochra). The abundance of crevice-nesting habitat 
at Anacapa Island suggests a potential for Anacapa Island to support 
large populations of these species (NPS 2000, p. 6). The removal of 
black rats from Anacapa Island would provide a substantial increase in 
nesting habitat available to these seabird species in California (NPS 
2000, p. 6). The removal of black rats would also benefit the Anacapa 
deer mouse in the long term. Rats may have been the cause of 
extirpation of deer mice from East Anacapa; deer mice were rediscovered 
there in 1997. If not eliminated, the black rats could lead to the 
extirpation of deer mice again, which could have serious implications 
for the birds of prey that rely on the deer mice as their primary prey 
base (NPS 2000, p. 53).
    We concur with the petitioners that the use of poison bait to kill 
black rats would also kill Anacapa deer mice. This was also recognized 
by the NPS (2000, pp. 1-139), and during implementation of the black 
rat eradication program, the remaining free-ranging Anacapa deer mice 
were killed (Howald et. al. 2005, p. 305). To prevent the extermination 
of the Anacapa deer mouse along with the black rats, the NPS developed 
and followed a mitigation plan for the Anacapa deer mouse (NPS 2000, 
pp. 1-139; Howald et. al. 2005, p. 302). The mitigation plan included 
conducting the black rat poisoning over a 2-year period, which allowed 
for staggering of the poisoning between East Anacapa and the other 
islets so that there would be free-ranging mice at all times on at 
least one of the islets. The mitigation plan also called for using bait 
that would degrade rapidly, capturing sufficient Anacapa deer mice to 
ensure success, releasing mice back to each islet at the appropriate 
time, providing supplemental food to the newly released

[[Page 56936]]

mice, and monitoring mouse populations over time (NPS 2000, pp. 17-18). 
The black rat eradication program began with the application of 
poisoned bait on East Anacapa in December 2001, followed by the release 
of the Anacapa deer mice held in captivity onto East Anacapa in spring 
2002 (NPS 2003, p. 1), and the poisoning of rats on Middle and West 
Anacapa in November 2002 (Howald et. al. 2005, p. 301). Finally, 
Anacapa deer mice were released on Middle and West Anacapa in spring 
2003 (NPS 2003, p. 1). Subsequent monitoring has shown that the 
eradication program successfully eliminated all black rats from the 
island (Howald et. al. 2005, p. 305).
    Prior to the application of poison to the island, genetic research 
indicated that deer mice from the three Anacapa islets were all the 
same subspecies (Pergrams et al. 2000, p. 828). A population viability 
analysis was conducted on the Anacapa deer mouse that indicated a total 
of 1,000 mice would be required to successfully repopulate the island 
and maintain genetic diversity (Pergrams et al. 2000, p. 829). However, 
to ensure that the Anacapa deer mouse subspecies was protected and that 
healthy deer mouse populations could be restored to Anacapa Island (NPS 
2003, p. 1), the NPS captured and released over 1,700 Anacapa deer mice 
(Howald et. al. 2005, p. 302). To further ensure the survival of the 
Anacapa deer mice released back to the island, the bait used for 
poisoning the rats was selected because it would break down in a matter 
of days (Howald et. al. 2005, p. 303), thereby eliminating the concern 
that captive Anacapa deer mice would be poisoned after being released 
back to the island. Many of the Anacapa deer mice were released in the 
early spring, which was considered the optimum time because it was the 
start of the breeding season and a time when natural food would be most 
abundant. Subsequent monitoring of the released population using 
marking and recapture techniques showed that the mice were reproducing 
in the wild and increasing in numbers (Faulkner 2003). By May 2003, the 
population of Anacapa deer mice on East Anacapa had increased to over 
8,000 individuals (NPS 2003, p. 1). By August 2003, the estimated 
number of Anacapa deer mice had increased to at least 16,000 on East 
Anacapa and 2,600 on Middle Anacapa (Faulkner 2003). Finally, the NPS 
concluded monitoring Anacapa deer mouse populations in Fall 2004, when 
the population was about 13,500 on East Anacapa, 23,400 on Middle 
Anacapa, and 42,500 on West Anacapa for a combined total of over 79,000 
mice (Gellerman 2005). The NPS did not conduct any type of genetic 
research on deer mice either while they were being held in captivity or 
after their release. Therefore, we cannot specifically address the 
possibility that genetic changes may have occurred in the captive deer 
mice. However, based on the rapid increase in numbers that occurred in 
the released deer mice, it is unlikely that any significant genetic 
change occurred during their captivity or if a change did occur, it was 
not detrimental to their recovery.
    As a result, we find that the petition, supporting information, and 
information readily available to the Service does not present 
substantial information for this factor indicating that the petitioned 
action may be warranted.
Finding
    We evaluated each of the five listing factors individually, and 
because the threats to the Anacapa deer mouse are not mutually 
exclusive, we also evaluated the collective effect of these threats. 
The petitioners raised a concern about the fact that the Anacapa deer 
mouse is restricted to a single island and therefore is vulnerable to 
extinction, but were primarily concerned that the NPS project to 
eradicate black rats from Anacapa Island with poison would result in 
the extinction of the Anacapa deer mouse, and that the NPS mitigation 
plan for the mouse was insufficient. When the petitioners submitted 
their petition in October 2002, the NPS had not yet completed either 
the process of eradicating black rats from the island or repopulating 
the island with captive Anacapa deer mice. Now that the project is 
completed, we know that the NPS was successful not only in eradicating 
black rats from the island but also protecting enough Anacapa deer mice 
to recover the population on the island. We conclude that the 
petitioners' concerns regarding the Anacapa deer mouse mitigation plan, 
including the likelihood of an insufficient number of captive mice to 
be successful, population crashes while in captivity, detrimental 
genetic change, timing of release, and longevity of poisoned bait, are 
no longer threats to the Anacapa deer mouse. We are unaware of any 
threats to the Anacapa deer mouse that would indicate that the long-
term viability of the subspecies is a concern and that the subspecies 
is either in danger of extinction throughout all or a significant 
portion of its range or likely to become an endangered species. 
Therefore, we find the petition, supporting information, and 
information readily available to the Service does not present 
substantial information indicating that the petitioned action may be 
warranted.
    We have reviewed the petition and literature cited in the petition 
and evaluated that information in relation to information available to 
us. After this review and evaluation, we find the petition does not 
present substantial scientific information to indicate listing the 
Anacapa deer mouse may be warranted at this time. Although we will not 
commence a status review in response to this petition, we will continue 
to monitor the subspecies' population status and trends, potential 
threats, and ongoing management actions that might be important with 
regard to the conservation of the Anacapa deer mouse across its range. 
We encourage interested parties to continue to gather data that will 
assist with the conservation of the subspecies. If you wish to provide 
information regarding the Anacapa deer mouse, you may submit your 
information or materials to the Field Supervisor, Ventura Fish and 
Wildlife Office (see ADDRESSES section).
References Cited
    A complete list of all references cited herein is available, upon 
request, from the Ventura Fish and Wildlife Office (see ADDRESSES 
section).
Author
    The primary author of this notice is the staff of the Ventura Fish 
and Wildlife Office (see ADDRESSES section).
Authority
    The authority for this action is section 4 of the Endangered 
Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: September 20, 2006.
Marshall P. Jones,
Acting Director, Fish and Wildlife Service.
 [FR Doc. E6-15874 Filed 9-27-06; 8:45 am]
BILLING CODE 4310-55-P