[Federal Register: July 29, 2008 (Volume 73, Number 146)]
[Proposed Rules]
[Page 43905-43910]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29jy08-17]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[FWS-R2-ES-2008-0060]; [1111-FY06-MO-B2]
Endangered and Threatened Wildlife and Plants; 90-Day Finding on
a Petition To List the Tucson Shovel-Nosed Snake (Chionactis
occipitalis klauberi) as Threatened or Endangered with Critical Habitat
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of 90-day petition finding and initiation of status
review.
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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 Tucson shovel-nosed snake
(Chionactis occipitalis klauberi) as threatened or endangered under the
Endangered Species Act of 1973, as amended (Act). We find that the
petition presents substantial scientific or commercial information
indicating that listing the Tucson shovel-nosed snake may be warranted.
Therefore, with the publication of this notice, we are initiating a
status review of the subspecies, and we will issue a 12-month finding
to determine if listing the subspecies is warranted. To ensure that the
status review of the Tucson shovel-nosed snake is comprehensive, we are
soliciting scientific and commercial information regarding this
subspecies.
DATES: To allow us adequate time to conduct a status review, we request
that information be submitted on or before September 29, 2008.
ADDRESSES: You may submit information by one of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the instructions for submitting comments.
U.S. mail or hand-delivery: Public Comments Processing,
Attn: FWS-R2-ES-2008-0060, Division of Policy and Directives
Management, U.S. Fish and Wildlife Service, 4401 N. Fairfax Drive,
Suite 222, Arlington, VA 22203.
We will not accept e-mail or faxes. We will post all information
received on http://www.regulations.gov. This generally means that we
will post any personal information you provide us (see the Information
Solicited section below for more details).
FOR FURTHER INFORMATION CONTACT: Steve Spangle, Field Supervisor,
Arizona Ecological Services Office, 2321 West Royal Palm Drive, Suite
103, Phoenix, AZ 85021; telephone 602-242-0210; facsimile 602-242-2513.
If you use a telecommunications device for the deaf (TDD), please call
the Federal Information Relay Service (FIRS) at 800-877-8339.
SUPPLEMENTARY INFORMATION:
Information Solicited
When we make a finding that a petition presents substantial
information indicating that listing a species may be warranted, we are
required to promptly commence a review of the status of the species. To
ensure that the status review is complete and based on the best
available scientific and commercial information, we are soliciting
information on the status of the Tucson shovel-nosed snake. We request
information from the public, other concerned governmental agencies,
Tribes, the scientific community, industry, or any other interested
parties concerning the status of the Tucson shovel-nosed snake. We are
seeking information regarding the subspecies' historical and current
status and distribution, its biology and ecology, its taxonomy
(especially genetics of the subspecies), ongoing conservation measures
for the subspecies and its habitat, and threats to either the
subspecies or its habitat.
If we determine that listing the Tucson shovel-nosed snake is
warranted, it is our intent to propose critical habitat to the maximum
extent prudent and determinable at the time we would propose to list
the subspecies. Therefore, with regard to areas within the geographical
range currently occupied by the Tucson shovel-nosed snake, we also
request data and information on what may constitute physical or
biological features essential to the conservation of the subspecies,
where these features are currently found, and whether any of these
features may require special management considerations or protection.
In addition, we request data and information regarding whether there
are areas outside the geographical area occupied by the subspecies that
are essential to the conservation of the subspecies. Please provide
specific information as to what, if any, critical habitat should be
proposed for designation, if the subspecies is proposed for listing,
and why that proposed habitat meets the requirements of the Act.
Please note that comments merely stating support or opposition to
the action under consideration without providing supporting
information, although noted, will not be considered in making a
determination, as section 4(b)(1)(A) of the Act directs that
determinations as to whether any species is a threatened or endangered
species must be made ``solely on the basis of the best scientific and
commercial data available.'' Based on the status review, we will issue
a 12-month finding on the petition, as provided in section 4(b)(3)(B)
of the Act.
You may submit your information concerning this finding by one of
the methods listed in the ADDRESSES section. We will not consider
submissions sent by e-mail or fax or to an address not listed in the
ADDRESSES section.
[[Page 43906]]
If you submit information via http://www.regulations.gov, your
entire submission--including any personal identifying information--will
be posted on the Web site. If your submission is made via a hardcopy
that includes personal identifying information, you may request at the
top of your document that we withhold this information from public
review. However, we cannot guarantee that we will be able to do so. We
will post all hardcopy submissions on http://www.regulations.gov.
Information and materials we receive, as well as supporting
documentation we used in preparing this finding, will be available for
public inspection on http://www.regulations.gov, or by appointment,
during normal business hours, at the U.S. Fish and Wildlife Service,
Arizona Ecological Services Office (see FOR FURTHER INFORMATION
CONTACT).
Background
Section 4(b)(3)(A) of the Act 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. Such findings are based on
information contained in the petition, supporting information submitted
with the petition, and information otherwise available in our files at
the time we make the finding. To the maximum extent practicable, we are
to make this finding within 90 days of receipt of the petition and
publish our notice of this finding promptly in the Federal Register.
Our standard for ``substantial information,'' as defined in the
Code of Federal Regulations at 50 CFR 424.14(b), with regards 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.'' If we find that substantial information was
presented, we are required to promptly commence a status review of the
species.
We evaluated the information provided by the petitioner in
accordance with 50 CFR 424.14(b). Our process for making this 90-day
finding under section 4(b)(3)(A) of the Act and 50 CFR 424.14(b) of our
regulations is limited to a determination of whether the information in
the petition meets the ``substantial scientific and commercial
information'' threshold (as mentioned above).
We received a petition, dated December 15, 2004, from the Center
for Biological Diversity (CBD) requesting that we list the Tucson
shovel-nosed snake as threatened or endangered throughout its range and
designate critical habitat within its range in the United States. The
petition, which was clearly identified as such, contained detailed
information on the natural history, biology, current status and
distribution of the Tucson shovel-nosed snake. It also contained
information on what the petitioner reported as potential threats to the
subspecies from urban development, agricultural practices, collecting,
inadequacy of existing regulations, drought, and climate change. In
response to the petitioner's requests, we sent a letter to the
petitioner, dated September 7, 2005, explaining that, due to funding
constraints in fiscal year 2005, we would not be able to address the
petition in a timely manner. On February 28, 2006, the petitioner filed
a 60-day notice of intent to sue (NOI) the Department of the Interior
for failure to issue 90-day and 12-month findings, and a proposed
listing rule, as appropriate, in response to the petition as required
by 16 U.S.C. 1533(b)(3)(A) and (B). In response to the NOI, we agreed
to submit a 90-day finding to the Federal Register as expeditiously as
possible.
The petition also requested that the Service consider an
``intergrade zone'' between the Tucson shovel-nosed snake and the
Colorado Desert shovel-nosed snake as part of the Tucson shovel-nosed
snake's range. An intergrade zone is an area of overlap between the
ranges of two subspecies where individuals may possess intermediate
characters or traits of both subspecies. It is generally recognized and
accepted by practitioners of subspecies taxonomy that intergrade zones
may exist between the ranges of two subspecies where the diagnostic
characters of both subspecies may be found (Mayr 1942, 1963, 1969,
1970; Huxley 1943; Wake 1997, 2006; Rodr[iacute]guez-Robles and De
Jesus-Escobar 2000; Isaac et al. 2004; Krysko and Judd 2006). Current
practice in the scientific literature is to objectively describe the
ranges of different subspecies and any intergrade zones between them
with narrative descriptions, maps, or both (e.g., Wake, 1997, 2006;
Rodr[iacute]guez-Robles and De Jesus-Escobar 2000; Mahrdt et al. 2001;
Leach[eacute] and Reeder, 2002; Krysko and Judd 2006). Following this
practice, intergrade zones are identified, but not assigned to either
of the subspecies. As such, we find that including all shovel-nosed
snakes within the intergrade zone in the subspecies taxon of the Tucson
shovel-nosed snake would not be consistent with current scientific
practice in describing the ranges of the subspecies and the intergrade
zone between them. Therefore, we do not consider shovel-nosed snakes
within the intergrade zone to be members of the Tucson shovel-nosed
snake subspecies, and thus they are not included in our threats
analysis below.
Previous Federal Action
No previous Federal action has been taken on the Tucson shovel-
nosed snake. The Tucson shovel-nosed snake has no Federal regulatory
status under the Act.
Species Information
The Tucson shovel-nosed snake was first described as a subspecies,
Sonora occipitalis klauberi, by Stickel in 1941. The genus was changed
to Chionactis from the genus Sonora two years later (Stickel 1943).
Since being described, the Tucson shovel-nosed snake has been widely
accepted as a subspecies (Klauber 1951, p. 187; Stebbins 2003, p. 394;
Crother 2008, p. 48), and is one of four currently recognized
subspecies of western shovel-nosed snakes, Chionactis occipitalis
(Crother 2008). In a recent study of genetic variation of mitochondrial
DNA, Wood et al. (2006) found significant geographical structuring
suggesting two distinct subspecies of western shovel-nosed snake rather
than four, combining western populations of C. o. occipitalis, the
Mojave shovel-nosed snake, with C. o. talpina, the Nevada shovel-nosed
snake; and eastern populations of C. o. occipitalis with C. o.
annulata, the Colorado Desert shovel-nosed snake, and C. o. klauberi.
However, Wood et al.'s inference was based on a single genetic marker
of mitochondrial DNA and did not include examination of nuclear
markers, which would more fully elucidate our understanding of the
taxonomic standing of this subspecies. Therefore, we continue to accept
the currently accepted designation of the subspecies C. o. klauberi.
The Tucson shovel-nosed snake is a small snake (250-425 millimeters
(mm) (9.84-16.73 inches (in)) total length) in the family Colubridae
with a shovel-shaped snout, an inset lower jaw, and coloring that
mimics coral snakes (Mahrdt et al. 2001, p. 731.1). The most notable
features of the Tucson shovel-nosed snake distinguishing it from the
other subspecies are (a) the red crossbands suffused with dark pigment,
making them appear brown or partly black, and (b) both black and red
crossbands not encircling the body (CBD 2004, p. 2).
Like other shovel-nosed snakes, the Tucson shovel-nosed snake uses
venom to capture arthropod prey (Rosen 2003).
[[Page 43907]]
The diet of shovel-nosed snakes consists of scorpions, beetle larvae,
spiders, crickets and centipedes (Rosen et al. 1996, p. 22-23). Like
the other subspecies, the Tucson shovel-nosed snake probably feeds on
scorpions. Glass (1972, p. 447) suggests that Tucson shovel-nosed
snakes may have developed a resistance to scorpion venom. Rosen et al.
(1996, p. 22) suggest that shovel-nosed snakes eat relatively
frequently. The authors (pp. 22-23) further support this observation by
noting that individual shovel-nosed snakes in captivity each consumed
five to eight crickets per week, and showed significant weight loss
after a two- to three-week lapse in feeding.
Like the other three subspecies of the western shovel-nosed snake,
the Tucson shovel-nosed snake uses ``sand swimming'' as its primary
locomotion. The snake moves using a sideways swaying motion while it is
either on or under the sand or loose soil (Stebbins 2003, p. 393).
Shovel-nosed snakes are primarily nocturnal in activity, although
specimens have been documented as active during daylight hours. Shovel-
nosed snakes are predominantly active at air temperatures between 70
and 90 degrees Fahrenheit (21 and 32 degrees Celsius), and from 7 p.m.
to 9 p.m. (Klauber 1951, p. 187). Rosen et al. (1996, p. 21) have also
observed that shovel-nosed snakes have been documented to be active in
the morning and just before sunset. Rosen et al. (1996, p. 21) further
note that activity seems to be highest when summer and spring
temperatures are moderate, and when the relative humidity is high.
Klauber (1951, p. 185) indicates that scattered sand hummocks,
crowned with mesquite or other desert shrubs, are favorite refuges for
shovel-nosed snakes. Rosen (2003, p. 8) suggests that the Tucson
shovel-nosed snake is found in more productive creosote-mesquite
floodplain environments, differing from the habitats preferred by other
subspecies of the western shovel-nosed snake. Rosen (2003, p. 8)
describes the associated soils of the Tucson shovel-nosed snake as
soft, sandy loams, with sparse gravel.
The subspecies is historically known from Pima County in the Avra
and Santa Cruz valleys and from southeastern Maricopa County and
southern Pinal County, including the Gila River Indian Community. The
area between the Tucson and Phoenix metropolitan areas is believed to
encompass the majority of the current range of this subspecies,
particularly west of Tucson northward along Avra Valley to Pinal
County, and westward into Maricopa County. The last verifiable record
of the Tucson shovel-nosed snake in Pima County was in 1979, near the
intersection of Avra Valley Road and Sanders Road in the Avra Valley
(Rosen 2003, p. 10). Although habitat still exists in Pima County, the
current distribution and abundance in Pima County is unknown. According
to the petition, most of the currently occupied range of the Tucson
shovel-nosed snake is believed to lie in southern Pinal County and
Maricopa County. An intergrade zone occurs between the range of the
Colorado Desert shovel-nosed snake and the range of the Tucson shovel-
nosed snake in Pima County (Klauber 1951, p. 159). Recent records of
shovel-nosed snakes in Pima County have been from within the intergrade
zone.
Threats Analysis
Section 4 of the Act (16 U.S.C. 1533), and its implementing
regulations (50 CFR 424) set forth the procedures for adding species to
the Federal Lists of Endangered and Threatened Wildlife and Plants. A
species, subspecies, or distinct population segment of vertebrate taxa
may be determined to be endangered or threatened 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 90-day finding, we evaluated whether information on
threats to the Tucson shovel-nosed snake, as presented in the petition,
and clarified by information readily available in our files at the time
of the petition review, is substantial, thereby indicating that the
petitioned action may be warranted. Our evaluation of this information
is presented below.
A. Present or Threatened Destruction, Modification, or Curtailment of
the Species' Habitat or Range
The petition states that the Tucson shovel-nosed snake is known
only from south central Arizona in Pima, Pinal, and Maricopa counties,
where it is dependent on Sonoran Desert scrub, particularly areas with
loose, sandy, wind-blown soils (CBD 2004, p. 6; Mattison 1989, p. 25).
According to the petitioner, much of the habitat within the former
range of the Tucson shovel-nosed snake has been converted to
agricultural fields and urban development, as well as new roads to
access these areas, all of which are unsuitable as habitat for this
subspecies. The petition further claims that once an area has been
plowed, or the soil has been compacted by urbanization or other
factors, it is unknown whether the habitat can ever be recovered and,
if so, how long it will take (CBD 2004, p. 10).
The petitioner cites a personal communication with herpetologist
Dr. Philip Rosen in which he pointed out that full recovery of native
vegetation to pre-disturbance conditions has not been documented, and
partial recovery of reptile and invertebrate groups has also not been
observed. We interpret partial recovery to mean either the re-invasion
of the disturbed lands by reptile and invertebrate groups or an
increase in their populations following a decline associated with the
disturbance. The petitioner notes that post-disturbance recovery (we
presume of both vegetation and wildlife) is possible with enough time,
but may not be practical because it may not provide habitat for the
Tucson shovel-nosed snake before it is extirpated from areas adjacent
to those rehabilitated habitats. The petitioner provided no data to
support such claims regarding habitat recovery.
To determine the historical and current distribution of Tucson
shovel-nosed snake habitat, the petitioner developed a model of the
snake's potential habitat with the cooperation of Dr. Rosen. The model
was developed and refined based on Dr. Rosen's professional knowledge
of habitat conditions, the conditions at observed locations, and
descriptions of habitat requirements from the literature.
Rosen (2003, p. 8) notes that significant amounts of Tucson shovel-
nosed snake habitat in the eastern portion of the Avra Valley in Pima
County was converted from desert to either agricultural or urban
development between 1954 and 1966, with many canals, wells, and field-
edge roads appearing in the interim. Rosen (2003, p. 7) also notes that
traffic in the Avra Valley increased after the 1960s, especially in the
late 1970s, following urban and agricultural development. Rosen (2003,
p. 8) further indicates that agricultural development was already
widespread in the western portion of the Avra Valley by 1959.
Surveys for the Tucson shovel-nosed snake began in the mid-to-late
1950s by Dr. Charles H. Lowe and his graduate students at the
University of Arizona, with a peak in the 1960s (Rosen 2003, p. 7). The
petition refers to records indicating the Tucson shovel-nosed snake was
reasonably abundant in the Avra Valley during the 1970s (Rosen 2003,
p.10). The last verifiable record of the Tucson shovel-nosed snake in
the
[[Page 43908]]
Avra Valley was in 1979, near the intersection of Avra Valley Road and
Sanders Road (Rosen 2003, p. 10). Surveys for the subspecies were
conducted in the Avra Valley and part of Pinal County in 2003, 2004 and
2007 (Rosen 2003, p. 6; Rosen 2004, p. 2; Rosen 2007, p. 1). Surveys
for shovel-nosed snakes were also conducted on Organ Pipe Cactus
National Monument in Pima County from 1987 through 1994 (Rosen et al.
1996, pp. 6-7). Additionally, surveys have been conducted
intermittently by various researchers throughout the range of the
Tucson shovel-nosed snake since the mid-1990s. During these recent
surveys, the Tucson shovel-nosed snake has been found in Pinal County
(Rosen 2003, p. 9; Rosen 2007, p. 2).
To determine the extent to which the Tucson shovel-nosed snake's
historical habitat has been lost to urban or agricultural development,
the petitioner combined the model of snake habitat (CBD 2004, p. 13)
with coverage of urban and agricultural areas developed by the
Southwestern Regional Gap Analysis Project, which used imagery current
to 2001. Their model of ``remaining good habitat'' (CBD 2004, p. 15)
covers roughly half of the historical range of the subspecies. Because
of a lack of available soils data, their model of historical habitat
does not include the entire range of the Tucson shovel-nosed snake on
lands in the east-central portion of Pinal and Maricopa counties. The
areas of habitat that were not modeled comprise approximately 25
percent of the historical range of the Tucson shovel-nosed snake. In
the areas modeled, the petitioner indicated that 1,271,319 acres (ac)
(514,503 hectares (ha)) of potential habitat occur within the range of
the Tucson shovel-nosed snake. Of this area, 914,015 ac (369,902 ha)
(72 percent) have been converted to either agriculture or urban
development (CBD 2004, p. 14). No estimates of habitat loss were
presented for areas not evaluated by the models.
The petitioner concluded that human population growth and habitat
loss predicted for Pima County also are likely to occur within the
species' range in Pinal and Maricopa counties, but did not provide
supporting citations or other information (CBD 2004, p. 14). We concur,
and have information readily available in our files that substantiates
human population growth and habitat loss are occurring, and will
continue to occur, in Pinal and Maricopa counties. For instance,
population growth in Pinal County is the sixth fastest among all
counties in the United States, and the current population of 313,000 is
predicted to grow to 600,000 by 2015 (Pisano 2007). The town of
Maricopa, which is within the current range of the Tucson shovel-nosed
snake in Pinal County, had a population of 4,855 in 2004, but is now
one of the country's fastest growing cities, and is planning for a
population of 350,000 by 2025 (Holcombe 2005). Additionally, a 275-
square-mile area of State Trust and private lands centered on Florence
Junction, also in Pinal County, is being planned for development
(Grammage 2006); approximately two thirds of this area falls within the
current range of the Tucson shovel-nosed snake. From July 2004 to July
2005, the population of Maricopa County increased by 137,000, which was
the largest numerical increase of any of the 3,141 counties in the
nation during that period (The Business Journal of Phoenix 2006). The
metropolitan areas of Tucson and Phoenix, between which the snake's
current range exists, are forecasted to meet and merge within a decade,
with the population increasing from 5 million today to upward of 10
million by 2040 (Reagor 2006).
The petition also lists mining, off-highway vehicles, construction
of roads, and livestock grazing as potential threats to the Tucson
shovel-nosed snake and its habitat. According to the petitioners (CBD
2004, p. 16), the Pima County Multi-Species Conservation Plan (2004)
indicates that off-highway vehicles can crush snakes buried in the sand
or compact soils used by the snake, although the Pima County Multi-
Species Conservation Plan (2004) does not provide specific evidence of
this threat. The petition further claims that construction of roads
fragments snake habitat, roads are a source of snake mortality, and
that livestock grazing compacts soils and may reduce the snake's prey
base by reducing and altering vegetation cover. No data or references
were provided to support the claims that mining and livestock grazing
are potential threats. Additionally, the petitioners provide no data to
support the claim that road construction fragments snake habitat and
roads are a source of snake mortality; however, we have information
from our files which supports this claim. Papers by Rosen and Lowe
(1994, pp. 146-148) and Andrews and Gibbons (2005, pp. 776-781) provide
substantial information indicating that road construction and increased
traffic on roads isolates habitat for snakes and increases snake
mortality.
We conclude that the petition provides substantial information to
support the claim that agricultural and urban development present
direct and indirect threats to the Sonoran Desert scrub habitat upon
which the Tucson shovel-nosed snake currently depends. Dr. Phil Rosen
has studied shovel-nosed snakes in Arizona for 17 years and has
coauthored one peer-reviewed journal article regarding the reproductive
ecology of C. occipitalis and coauthored a literature review of both
species. Dr. Rosen has studied herpetology in the American Southwest
for almost 30 years and has been instrumental in various aspects of
conservation of reptiles and amphibians in the southwestern United
States. Dr. Rosen has been active in helping Pima County develop the
Sonoran Desert Conservation Plan, particularly with regard to the
reptiles and amphibians being considered for protection in the plan.
Additionally, Dr. Rosen has worked with the Town of Marana to help
develop their Habitat Conservation Plan, which also considers the
conservation of local reptiles. Both the Sonoran Desert Conservation
Plan and the Town of Marana Habitat Conservation Plan are considering
conservation of the Tucson shovel-nosed snake, and Dr. Rosen has helped
them develop habitat models of what constitutes Tucson shovel-nosed
snake habitat, including former habitat and remaining habitat. Although
the petition relies heavily on non-peer-reviewed literature to support
its claims regarding loss and degradation of Tucson shovel-nosed snake
habitat, we find that the data presented, as well as clarifying
information in our files, relating to threats from agricultural and
urban development are credible and substantial, indicating that listing
the Tucson shovel-nosed snake may be warranted.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
The petition claims that scientific and commercial collection is
not widespread, but that the Tucson shovel-nosed snake could be
somewhat affected by collection in limited areas. The petition further
claims that enforcement of laws prohibiting commercial collection of
reptiles is limited. While we accept the claim that the Tucson shovel-
nosed snake occurs within a limited distribution in Arizona, the
petition does not provide data to substantiate the claim that the
subspecies may be threatened by collection. Therefore, we find that the
petition does not provide substantial information to support the claim
that overutilization for commercial, recreational, scientific, or
educational purposes may pose a significant threat to the Tucson
shovel-nosed snake.
[[Page 43909]]
C. Disease or Predation
The petitioner presented no data that diseases affect Tucson
shovel-nosed snakes. The petitioner provided data that predation by
native wildlife occurs on Colorado Desert shovel-nosed snakes (Funk
1965, p. 16; Mahrdt and Banta 1996, p. 81). It is likely that predation
also occurs on Tucson shovel-nosed snakes since most of the native
wildlife occurs within the range of both subspecies; however, the
petitioner provided no data to support predation as a significant
impact to populations of Tucson shovel-nosed snakes. Therefore, we find
that the petition does not provide substantial information that listing
the subspecies due to disease or predation may be warranted.
D. Inadequacy of Existing Regulatory Mechanisms
The petition claims the Tucson shovel-nosed snake is not currently
afforded any State or Federal protection and is not listed on any State
or Federal list of species of concern. The petitioner indicated that,
according to the Arizona Game and Fish Department's Wildlife Management
Program Strategic Plan for the Years 2001-2006, the Tucson shovel-nosed
snake is not included on Arizona's Wildlife of Special Concern list
(Arizona Game and Fish Department 2001). The petitioner further stated
that, even if the Tucson shovel-nosed snake was considered Wildlife of
Special Concern, it would receive little protection because the list
only serves to notify the public of the species' status and does not
require any conservation or management actions (Arizona Game and Fish
Department 2001). Since we received the petition, the Arizona Game and
Fish Department has developed Arizona's Comprehensive Wildlife
Conservation Strategy: 2005-2015 (CWCS), in which the Tucson shovel-
nosed snake has been identified as a Species of Greatest Conservation
Need for which immediate conservation action is necessary (Tier 1b
under the Vulnerable category) (Arizona Game and Fish Department 2006,
Appendix A p. 3, Appendix K p. 139). However, the CWCS was not designed
to replace or duplicate the Department's existing wildlife management
strategic plan (Arizona Game and Fish Department 2001), nor does it
provide further regulatory protection for the snake. It serves only to
prioritize funds and guide implementation of conservation activities
for Arizona's vulnerable wildlife (Arizona Game and Fish Department
2006, p. 9).
The petitioner claims that approximately 21 percent of the Tucson
shovel-nosed snake's historical range (including the intergrade zone)
occurs on lands administered by the State of Arizona. The percentage of
State of Arizona lands within the current range (and excluding the
intergrade zone) was not presented and is unknown to the Service. The
State of Arizona currently has no regulations or programs to protect
the Tucson shovel-nosed snake. The petitioner pointed out that the
Federal Enabling Act for Arizona and the State Constitution limit
conservation on State lands by requiring that use of the lands maximize
the economic value of State lands to benefit schools. The petition
further describes the Arizona Preserve Initiative (HB 2555) passed in
1996, which establishes a process by which State lands can be leased or
purchased for conservation purposes; however, the petitioner claims
that the legality of this law is in question because of the Arizona
State Constitutional requirement to maximize economic value. The
petitioner also claims that even without its legality issues, the
Arizona Preserve Initiative provides little protection for the Tucson
shovel-nosed snake because it only allows for the lease and purchase of
State land. The Arizona Preserve Initiative does not require any
purchase or lease to conserve habitat for the snake. Although State
lands currently provide open space, there are no known plans to require
protection of Tucson shovel-nosed snake habitat on State lands, and no
other protections are afforded the snake on State lands.
The petition claims that enforcement of laws prohibiting commercial
collection of reptiles is limited. State law limits the collection of
non-protected snakes to no more than four individuals of a species per
year with a valid hunting license. If more than four are to be
collected (e.g., for research purposes), a scientific collecting permit
must be obtained. It is illegal to commercially sell, barter, or trade
any native Arizona wildlife. While we are aware that the Arizona Game
and Fish Department enforces these laws to the extent that it can, it
is likely that some level of illegal collection of shovel-nosed snakes
occurs. We do not, however, have information indicating the level of
this illegal activity, nor how it impacts the population as a whole.
The petition states that 16 percent of the Tucson shovel-nosed
snake's habitat occurs on Bureau of Land Management (BLM) lands, most
of which falls within the intergrade zone of the snake. The intergrade
zone is an area not included in this analysis (see Background). Of the
remaining area (not within the intergrade zone), the petition states
that the recent creation of the Ironwood Forest National Monument,
which is administered by the BLM, provides the Tucson shovel-nosed
snake possible protections. Additionally, we are aware of BLM lands
between Tucson and Florence, Arizona, that may support habitat for the
Tucson shovel-nosed snake for which the petitioner provided no
information on status or threats.
The BLM currently has no regulations to protect the Tucson shovel-
nosed snake, does not survey for the snake on its habitat, and does not
consider impacts on the subspecies during project-specific analyses.
BLM lands are secure from agricultural and urban development; however,
as previously mentioned, the petitioner claims that off-highway vehicle
use, livestock grazing, roads, and mine leasing are all potential
threats to Tucson shovel-nosed snakes and their habitat. The petitioner
admitted that the extent of these threats and their impacts on the
Tucson shovel-nosed snake have not been studied, but they expect that
they are likely impacting the snake to some unknown level. Impacts from
these activities may exist; however, the petition provides no data to
support these claims.
The petitioner points to the perceived inadequacies in the Pima
County Multi-species Conservation Plan (referred to in the petition as
the Sonoran Desert Conservation Plan) and the Town of Marana Habitat
Conservation Plan as regulatory mechanisms. Because neither of these
plans is finalized, we will not explore the adequacies of these plans
as possible regulatory mechanisms for the snake.
The petition provides no information about existing regulatory
mechanisms on lands managed by the Gila River Indian Community, which
is within the current range of the Tucson shovel-nosed snake. The
petition does state that 17 percent of the snake's habitat is under the
control of the Tohono O'odham Nation. Most of the Tohono O'odham lands
are in Pima County west of Tucson, with a small portion falling within
Pinal and Maricopa counties. All of these lands are within the
intergrade zone, which we have excluded from consideration.
We have reviewed the information provided in the petition as well
as all sources cited in the petition. Many of the regulatory mechanisms
discussed pertain to lands that are in the intergrade zone of the
snake, which we have excluded from this analysis. For the remaining
areas within the snake's range, we conclude that the petition and
information in our files present substantial information that existing
regulatory mechanisms may be
[[Page 43910]]
inadequate to prevent the progressive decline of populations of the
Tucson shovel-nosed snake and its habitat.
E. Other Natural or Manmade Factors Affecting the Species' Continued
Existence
The petition claims that severe weather, particularly prolonged
drought, has the potential to negatively impact Tucson shovel-nosed
snake populations. The petitioner described prolonged drought as a
potential reason that no Tucson shovel-nosed snakes were located in the
Avra Valley within the historical range in Pima County during extensive
searches by local researchers (Rosen 2003, p. 16). No data to support
this claim were provided by the petitioner or by Rosen (2003), and
although we have information in our files indicating that conditions in
the United States (Intergovernmental Panel on Climate Change 2007, p.
9), and in the southwestern United States in particular (Seager et al.
2007, p. 1181) are likely to be drier and warmer in the near future, we
have no information indicating such changes will negatively impact the
Tucson shovel-nosed snake. The petitioner also claims that, in addition
to prolonged drought, climate change or habitat modification that
results in permanently wetter environmental conditions could also lead
to further declines of this arid-adapted subspecies, particularly under
prevailing conditions in which only fragments of the original
distribution remain occupied. However, the petition provides no data to
support the claim that climate change will result in wetter
environmental conditions within the current range of the species, nor
does it provide data to support the claims that the Tucson shovel-nosed
snake responds negatively to wetter environmental conditions and that
fragmented habitat would exacerbate negative impacts due to wetter
conditions. Therefore, we do not find that the petition provides
substantial information to support the claim that prolonged drought or
climate change pose significant threats to the Tucson shovel-nosed
snake.
Finding
We have reviewed the petition and the literature cited in the
petition, and evaluated the information to determine whether the
sources cited support the claims made in the petition. We also reviewed
reliable information that was readily available in our files to clarify
and verify information in the petition. Based on our evaluation of the
information provided in the petition, and in accordance with recent
applicable court decisions pertaining to 90-day findings, we find that
the petition presents substantial scientific information indicating
that listing the Tuscon shovel-nosed snake may be warranted. Our
process for making this 90-day finding under section 4(b)(3)(A) of the
Act is limited to a determination of whether the information in the
petition presents ``substantial scientific and commercial
information,'' which is interpreted in our regulations as ``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)).
The petitioners presented substantial information indicating that
the Tucson shovel-nosed snake may be threatened by Factors A and D
throughout the entire range of the subspecies. The petitioners did not
present substantial information that Factors B, C and E are currently,
or in the future, considered a threat to this species. Based on this
review and evaluation, we find that the petition has presented
substantial scientific or commercial information that listing the
Tucson shovel-nosed snake throughout all or a portion of its range may
be warranted due to current and future threats under Factors A and D.
As such, we are initiating a status review to determine whether listing
the Tucson shovel-nosed snake under the Act is warranted. We will issue
a 12-month finding as to whether any of the petitioned actions are
warranted. To ensure that the status review is comprehensive, we are
soliciting scientific and commercial information regarding the Tuscon
shovel-nosed snake.
It is important to note that the ``substantial information''
standard for a 90-day finding is in contrast to the Act's ``best
scientific and commercial data'' standard that applies to a 12-month
finding as to whether a petitioned action is warranted. A 90-day
finding is not a status assessment of the species and does not
constitute a status review under the Act. Our final determination as to
whether a petitioned action is warranted is not made until we have
completed a thorough status review of the species, which is conducted
following a positive 90-day finding. Because the Act's standards for
90-day and 12-month findings are different, as described above, a
positive 90-day finding does not mean that the 12-month finding also
will be positive.
References Cited
A complete list of all references cited is available, upon request,
from the Arizona Ecological Services Office (see FOR ADDITIONAL
INFORMATION CONTACT section).
Author
The primary author of this notice is the Arizona Ecological
Services Office (see FOR ADDITIONAL INFORMATION CONTACT 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: July 14, 2008.
Kenneth Stansell,
Deputy Director, U.S. Fish and Wildlife Service.
[FR Doc. E8-17221 Filed 7-28-08; 8:45 am]
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