[Federal Register: July 16, 2009 (Volume 74, Number 135)]
[Proposed Rules]
[Page 34539-34548]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16jy09-14]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[FWS-R1-ES-2008-0084; 14420-1113-0000-C6]
RIN 1018-AW16
Endangered and Threatened Wildlife and Plants; 12-Month Finding
on a Petition To Remove the Utah (Desert) Valvata Snail (Valvata
utahensis) From the List of Endangered and Threatened Wildlife and
Proposed Rule
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of 12-month petition finding; proposed rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a
12-month finding on a petition to remove the Utah (desert) valvata
snail (Valvata utahensis) from the Federal List of Endangered and
Threatened Wildlife (List) pursuant to the Endangered Species Act of
1973, as amended (Act) (16 U.S.C. 1531 et seq.). Based on a thorough
review of the best available scientific and commercial data, the Utah
valvata snail is more widespread and occurs in a greater variety of
habitats in the Snake River than known at the time of listing in 1992.
We now know that the Utah valvata snail is not limited to areas of
cold-water springs or spring outflows; rather, it persists in a variety
of aquatic habitats, including cold-water springs, spring creeks and
tributaries, the mainstem Snake River and associated tributary stream
habitats, and reservoirs influenced by dam operations. Given our
current understanding of the species' habitat requirements and threats,
the species does not meet the definition of a threatened or endangered
species under the Act. Therefore, we are proposing to remove the Utah
valvata snail from the List, thereby removing all protections provided
by the Act.
DATES: We will accept comments from all interested parties until
September 14, 2009. We must receive requests for public hearings, in
writing, at the address shown in the FOR FURTHER INFORMATION CONTACT
section by August 31, 2009.
ADDRESSES: You may submit comments 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: RIN 1018-AW16, 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 comments on
http://www.regulations.gov. This generally means that we will post any
personal information you provide us (see the Public Comments Solicited
section below for more information).
FOR FURTHER INFORMATION CONTACT: Jeffery L. Foss, State Supervisor,
Idaho Fish and Wildlife Office, 1387 S. Vinnell Way, Room 368, Boise,
ID 83709 (telephone 208/378-5243; facsimile 208/378-5262). Persons who
use a telecommunications device for the deaf (TDD) may call the Federal
Information Relay Service (FIRS) at 800/877-8339, 24 hours a day, 7
days a week.
SUPPLEMENTARY INFORMATION:
Public Comments Solicited
Our intent is to use the best available commercial and scientific
data as the foundation for all endangered and threatened species
classification decisions. Comments or suggestions from the public,
other concerned governmental agencies, the scientific community,
industry, or any other interested party concerning this proposed rule
to remove the Utah valvata snail from the List are hereby solicited.
Comments particularly are sought concerning:
(1) Additional information regarding the range, distribution, and
population size of the Utah valvata snail, including the locations of
any additional colonies or populations;
(2) Data on any threats (or lack thereof) to the Utah valvata
snail;
(3) Current or planned activities in the areas occupied by the Utah
valvata snail
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and possible impacts of these activities on this species; and
(4) Data on Utah valvata snail population trends.
You may submit your comments and materials concerning this proposed
rule by one of the methods listed in the ADDRESSES section. We will not
accept comments sent by e-mail or fax or to an address not listed in
the ADDRESSES section.
We will post your entire comment--including your personal
identifying information--on http://www.regulations.gov. If you provide
personal identifying information in addition to the required items
specified in the previous paragraph, such as your street address, phone
number, or e-mail address, 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.
Comments and materials we receive, as well as supporting
documentation we used in preparing this proposed rule, will be
available for public inspection on http://www.regulations.gov, or by
appointment, during normal business hours at the Idaho Fish and
Wildlife Office, 1387 S. Vinnell Way, Room 368, Boise, ID 83709; by
telephone at 208/378-5243.
Public Hearing
The Act provides for one or more public hearings on this proposal,
if requested. Requests must be received by the date specified in the
DATES section. Such requests must be made in writing and addressed to
the State Supervisor (see FOR FURTHER INFORMATION CONTACT section
above).
Species Information
The Utah valvata snail (Valvata utahensis) was first recognized as
a species in 1902 from specimens in Utah Lake and Bear Lake, Utah
(Walker 1902, p. 125). Its common name has since been changed by the
American Fisheries Society to the ``desert valvata'' in the benchmark
text for aquatic invertebrate nomenclature, Common and Scientific Names
of Aquatic Invertebrates from the United States and Canada (Turgeon et
al. 1998, p. 109), presumably due to the fact that it is no longer
known to occur in Utah. However, because the species is currently
listed in the Code of Federal Regulations as the Utah valvata snail,
Valvata utahensis will be referred to as the Utah valvata snail
throughout this proposed rule.
The Utah valvata snail is univoltine (produces one group of eggs
per year) with a lifespan of about 1 year. Reproduction and spawning
occur asynchronously between March and October, depending on habitat,
with the majority of young spawned between August and October (Cleland
1954, pp. 171-172; U.S. Bureau of Reclamation (USBR) 2003, p. 7).
Emergence of a new cohort follows approximately 2 weeks after
oviposition (Cleland 1954, p. 170; Dillon 2000, p. 103), and senescent
snails (i.e., those approximately 374 days old) die shortly after
reproduction (Cleland 1954, pp. 170-171; Lysne and Koetsier 2006a, p.
287).
Lysne and Koetsier (2006a, p. 288) determined the average size of
adult Utah valvata snails to be 0.17 inches (4.32 millimeters (mm)).
The Utah valvata snail has been observed to produce egg masses which
contained 3 to 12 developing snails (Lysne and Koetsier 2006a, p. 288).
Egg masses are approximately 0.39 to 0.06 inches (1.0 to 1.5 mm) in
diameter, and young snails are approximately 0.03 inches (0.7 mm) in
size upon emergence (Lysne and Koetsier 2006a, p. 289). Utah valvata
snail young possess a turbinate shell form and an incipient carina
(keel-shaped ridge) on the dorsal surface of the shell, which
distinguishes them from the morphologically similar Valvata humeralis.
Based on field and laboratory observations, the Utah valvata snail is
primarily a grazer (Lysne and Koetsier 2006a, p. 287; Frest and
Johannes 1992, pp. 13-14).
Range
The Utah valvata snail, or at least its closely related ancestors,
has been described as ranging widely across the western United States
and Canada as far back as the Jurassic Period, 199.6 0.6
to 145.5 4 million years ago (Taylor 1985a, p. 268).
Fossils of the Utah valvata snail are known from Utah to California
(Taylor 1985a, pp. 286-287). The Utah valvata snail was likely present
in the ancestral Snake River as it flowed south from Idaho, through
Nevada, and into northeastern California (Taylor 1985a, p. 303). The
Snake River escaped to join the Columbia River Basin approximately 2
million years ago (Hershler and Liu 2004, pp. 927-928).
At the time of listing in 1992 (57 FR 59244, December 14, 1992) we
reported the range of the Utah valvata snail as existing at a few
springs and mainstem Snake River sites in the Hagerman Valley, Idaho
(River Mile (RM) 585), a few sites above and below Minidoka Dam (RM
675), and in the American Falls Dam tailwater near Eagle Rock damsite
(RM 709). Surveys at the State of Idaho's Thousand Springs Preserve (RM
585) indicated declining numbers of snails, with two colonies at or
below 6,000 individuals (57 FR 59245).
New data collected since the time of listing indicate that the
range of the species is discontinuously distributed in at least 255
miles (410 kilometers (km)) of the Snake River and some associated
tributary streams, an increase of nearly 122 river miles (196 km) from
the previously known range. Their current range in the Snake River
extends from RM 585 near the Thousand Springs Preserve (Bean 2005),
upstream to the confluence of the Henry's Fork with the Snake River (RM
837; Fields 2005, p. 11). Colonies of the Utah valvata snail have been
found in the Snake River near the towns of Firth (RM 777.5), Shelley
(RM 784.6), Payne (RM 802.6), Roberts (RM 815), and in the Henrys Fork
approximately 9.3 miles (15 km) upstream from its confluence with the
Snake River (at Snake RM 832.3) (Gustafson 2003). Based on limited
mollusk surveys, the species has not been found upstream from the
described location on the Henry's Fork or in the South Fork of the
Snake River. Tributary streams to the Snake River where Utah valvata
snails have been collected include Box Canyon Creek (RM 588) (Taylor
1985b, pp. 9-10), and at one location in the Big Wood River (WRM 35)
(USBR 2003, p. 22). Big Wood River observations require further
investigation and may be the result of seasonal transport of Utah
valvata snails via irrigation canals that connect the Big Wood and
Snake Rivers, or passive transport via waterfowl (Miller et al. 2006,
p. 2371) between large bodies of water (i.e., reservoirs).
Habitat Use
At the time of listing in 1992, the best available data indicated
that Utah valvata snails ``characteristically require cold, fastwater,
or lotic habitats * * * in deep pools adjacent to rapids or in
perennial flowing waters associated with large spring complexes'' (57
FR 59244, December 14, 1992). In numerous field studies conducted since
then, the species has been collected at a wide range of depths, ranging
from less than 3.2 feet (1 meter) (Stephenson and Bean 2003, pp. 98-99)
to depths greater than 45 feet (14 meters) (USBR 2003, p. 20), and at
temperatures between 37.4 and 75.2 degrees Fahrenheit (F) (4 to 24
degrees Celsius (C)) (Lysne 2007; Gregg 2006).
Recent work conducted by the Idaho Department of Fish and Game
(IDFG) in the upper Snake River demonstrated that Utah valvata snail
presence was positively correlated with water depth (up to 18.37 feet
(5.6 meters)) and temperature (up to 63 degrees F (17.2
[[Page 34541]]
degrees C)) (Fields 2005, pp. 8-9), and Utah valvata snail density was
positively correlated with macrophyte (a water plant large enough to be
observed with the unaided eye) coverage, water depth, and temperature
(Fields 2006, p. 6). Similarly, Hinson (2006, pp. 28-29) analyzed
available data from several studies conducted by the USBR (2001-2004),
Idaho Power Company (IPC) (1995-2002), IDFG, Idaho Transportation
Department (2003-2004) and others, and demonstrated a positive
relationship between Utah valvata snail presence and macrophytes,
depth, and fine substrates. One study reported Utah valvata snails in
organically enriched fine sediments with a heavy macrophyte community,
downstream of an aquaculture facility (RM 588) (Hinson 2006, pp. 31-
32).
Survey data and information reported since the time of listing
demonstrate that the Utah valvata snail is able to live in reservoirs,
which were previously thought to be unsuitable for the species (Frest
and Johannes 1992, pp. 13-14; USBR 2002, pp. 8-9; Fields 2005, p. 16;
Hinson 2006, pp. 23-33). We now know the Utah valvata snail persists in
a variety of aquatic habitats, including cold-water springs, spring
creeks and tributaries, the mainstem Snake River and associated
tributary stream habitats, and reservoirs.
Alterations of the Snake River, including the construction of dams
and reservoir habitats, have changed fluvial processes resulting in the
reduced likelihood of naturally high river flows or rapid changes in
flows, and the retention of fine sediments (U.S. Environmental
Protection Agency (USEPA) 2002, pp. 4.30-4.31), which may also increase
potential habitat for the species (e.g., Lake Walcott and American
Falls Reservoirs). Utah valvata snail surveys conducted downstream from
American Falls Dam (RM 714.1) to Minidoka Dam (RM 674.5), from 1997 and
2001-2007, consistently found Utah valvata snails on fine sediments
within this 39-mile (62.9 km) river/reservoir reach of the Snake River
(USBR 1997, p. 4; USBR 2003, p. 8; USBR 2004, p. 5; USBR 2005, p. 6;
USBR 2007, pp. 9-11; USFWS 2005, p. 119). Surveys conducted downstream
of Minidoka Dam (RM 674.5) to Lower Salmon Falls Dam (RM 573.0) have
detected Utah valvata snails, including one record from the tailrace
area of Minidoka Dam in 2001 (USFWS 2005, p. 120).
In summary, based on available information, the Utah valvata snail
is not as specialized in its habitat needs as we thought at the time of
listing. In the Snake River, the species inhabits a diversity of
aquatic habitats throughout its 255-mile (410 km) range, including
cold-water springs, spring creeks and tributaries, mainstem and free-
flowing waters, reservoirs, and impounded reaches. The species occurs
on a variety of substrate types including both fine sediments and more
coarse substrates in areas both with and without macrophytes. It has
been collected at water depths ranging from less than 3.2 feet (1
meter) to greater than 45 feet (14 meters), and at water temperatures
ranging from 37.4 to 75.2 degrees F (3 to 24 degrees C).
Population Density
The density of Utah valvata snails at occupied sites can vary
greatly. For example, at one cold-water spring site at the Thousand
Springs Preserve, the average density in 2003 was 197 snails/square
meter (m\2\) (ranging between 0 and 1,724 snails/m\2\) (Stephenson et
al. 2004, p. 23). In the mainstem Snake River between American Falls
Reservoir and Minidoka Dam in 2002, Utah valvata snail densities
averaged 91 snails/m\2\ (ranging from 0 to 1,188 snails per m\2\), and
in American Falls Reservoir densities averaged 50 snails/m\2\ (range
unavailable) (USBR 2003, p. 20). Above American Falls Reservoir in the
mainstem Snake River, Utah valvata snail densities at six sites
averaged 117 snails/m\2\ (ranging from 0 to 1,716 snails/m\2\) (Fields
2006, pp. 12-13).
Within reservoirs, the proportional occurrence of snails is
relatively high. For all field studies and surveys, the highest
proportions of samples where Utah valvata snails are present have been
collected in lower Lake Walcott Reservoir (USBR 2002, p. 5; USBR 2003,
p. 6). For sample years 2001 to 2006, the relative proportion of
samples containing Utah valvata snails ranged from 40 (in 2004) to 62
(in 2002) percent of samples collected. Similarly, American Falls
reservoir samples contain a high proportion of Utah valvata snails with
21 (in 2001) to 33 (in 2003) percent in collections between 2002
through 2004. Such high proportional occurrence in reservoirs is
additional evidence that Utah valvata snails are not restricted to
cold-water springs or their outflows.
Previous Federal Actions
We listed the Utah valvata snail as endangered on December 14, 1992
(57 FR 59244). Based on the best available data at that time we
determined that the Utah valvata snail was threatened by: Proposed
construction of new hydropower dams, the operation of existing
hydropower dams, degraded water quality, water diversions, the
introduced New Zealand mudsnail (Potamopyrgus antipodarum), and the
lack of existing regulatory protections (57 FR 59244). In 1995, we
published the Snake River Aquatic Species Recovery Plan (Plan), which
included the Utah valvata snail. Critical habitat has not been
designated for this species.
On April 11, 2006, we initiated a 5-year review for the species in
accordance with section 4(c)(2) of the Act (71 FR 18345). On December
26, 2006, the Service received a petition from the Governor of Idaho
and attorneys from several irrigation districts and canal districts
requesting that the Utah valvata snail be removed from the List. On
June 6, 2007, the Service published a Federal Register notice
announcing that the petition presented substantial scientific
information indicating that removing the Utah valvata snail from the
List may be warranted, and the initiation of a 12-month status review
of the species, to be conducted concurrent with our 5-year review (72
FR 31264). As part of our best available scientific and commercial data
analysis, we conducted a 30-day peer review on a draft status-review
document, which was completed in September 2007 (USFWS 2007). The
Summary of Factors Affecting the Species section below represents the
best available scientific and commercial data resulting from our
analysis and applicable updates from the previous peer review process.
Summary of Factors Affecting the Species
Section 4 of the Act (16 U.S.C. 1533) and implementing regulations
(50 CFR part 424) set forth procedures for adding species to, removing
species from, or reclassifying species on the Federal List of
Endangered and Threatened Wildlife. Changes in the List can be
initiated by the Service or through the public petition process.
Section 4 (b)(3)(A) of the Act (16 U.S.C. 1531 et seq.) requires that,
for any petition containing substantial scientific and commercial
information that listing may be warranted, we make a finding within 12
months of receiving the petition on whether the petitioned action is:
(a) Not warranted, (b) warranted, or (c) warranted, but that immediate
proposal of a regulation implementing the petitioned action is
precluded by pending proposals to determine whether other species are
threatened or endangered.
Under section (4) of the Act, a species may be determined to be
endangered or threatened on the basis of any of the following five
factors: (A) Present or
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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. We must consider these same five
factors in delisting a species. We may delist a species according to 50
CFR 424.11(d) if the best available scientific and commercial data
indicate that the species is neither endangered nor threatened for the
following reasons: (1) The species is extinct; (2) the species has
recovered and is no longer endangered or threatened; and/or (3) the
original scientific data used at the time the species was classified
were in error.
A species is ``endangered'' for purposes of the Act if it is in
danger of extinction throughout all or a significant portion of its
range and is ``threatened'' if it is likely to become endangered within
the foreseeable future throughout all or a significant portion of its
range. The word ``range'' in the significant portion of its range (SPR)
phrase refers to the range in which the species currently exists. The
word ``significant'' in the SPR phrase refers to the value of that
portion to the conservation of the species.
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of the Species' Habitat or Range
Construction of New Hydropower Dams
In our 1992 final rule listing the Utah valvata as an endangered
species, we stated: ``Six proposed hydroelectric projects, including
two high dam facilities, would alter free-flowing river reaches within
the existing range of [the Utah valvata snail]. Dam construction
threatens the [Utah valvata snail] through direct habitat modification
and moderates the Snake River's ability to assimilate point and non-
point pollution. Further hydroelectric development along the Snake
River would inundate existing mollusk habitats through impoundment,
reduce critical shallow, littoral shoreline habitats in tailwater areas
due to operating water fluctuations, elevate water temperatures, reduce
dissolved oxygen levels in impounded sediments, and further fragment
remaining mainstem populations or colonies of these snails'' (57 FR
59251).
Since the time of listing, proposed hydroelectric projects
discussed in the 1992 final rule are no longer moving forward. The A.J.
Wiley project and Dike Hydro Partners preliminary permits have lapsed;
the Kanaka Rapids, Empire Rapids, and Boulder Rapids permits were
denied by the Federal Energy Regulatory Commission (FERC) in 1995;
there was a notice of surrender of the preliminary permit for the River
Side Project in 2002; and two other proposed projects, the Eagle Rock
and Star Falls Hydroelectric Projects were denied preliminary permits
by the FERC. In 2003, a notice was provided of surrender of preliminary
permit for the Auger Falls Project. Information provided by the State
of Idaho indicates that all proposals and preliminary permits for the
construction of new dams along the mid-Snake River have either lapsed
or been denied by the FERC (Caswell 2006). Additionally, recent studies
have shown that the Utah valvata snail is not as limited in its habitat
needs as we had thought at the time of listing (see Species Information
section above).
Operation of Existing Hydropower Dams
In the 1992 final rule, we discussed peak-loading, the practice of
artificially raising and lowering river levels to meet short-term
electrical needs by local run-of-the-river hydroelectric projects, as a
threat to the Utah valvata snail. Peak-loading was described as ``a
frequent and sporadic practice that results in dewatering mollusk
habitats in shallow, littoral shoreline areas'' (57 FR 59252). Studies
conducted since the time of listing have shown the Utah valvata snail
is able to persist in reservoirs, contrary to our understanding of the
species at the time of listing (USFWS 2005, p. 105; 57 FR 59244,
59245). For example, Lake Walcott (RM 702.5 to 673.5; upstream of
Minidoka Dam) appears to contain the largest population of Utah valvata
snails in the Snake River system (USFWS 2005, pp. 111-112). This is
likely due to relatively good water quality in the reservoir compared
to downstream sections of the Snake River near Hagerman where water
quality is influenced by agricultural, municipal, and aquaculture flows
into the river. In lower Lake Walcott, there is a large area of
suitable Utah valvata snail habitat that remains submerged despite
annual drawdowns (the reservoir fluctuates by no more than 5 feet (1.5
meters) annually, thereby limiting the number of snails affected by
dewatering and desiccation). Further, surveys conducted in the mainstem
Snake River in 1997, 1998, and 2001, from American Falls Dam (RM 714.1)
to Lake Walcott (RM 702.5) indicate a fairly large and viable
population of Utah valvata snails even though shoreline habitats in
this stretch undergo annual dewatering (USFWS 2005, p. 119). In
American Falls reservoir, dam operations and fluctuating flows have
been estimated to kill between 5 and 40 percent of the Utah valvata
snails in most years. Nevertheless, Utah valvata snails continue to
persist in these reservoirs with relatively high proportional
occurrence (USFWS 2005, p. 119).
Degraded Water Quality
In the final listing rule, we stated: ``The quality of water in
[snail] habitats has a direct effect on the species [sic] survival. The
[Utah valvata snail] require[s] cold, well-oxygenated unpolluted water
for survival. Any factor that leads to deterioration in water quality
would likely extirpate [the Utah valvata snail]'' (57 FR 59252). As
described above in the Species Information section, our understanding
of the species' habitat requirements has changed substantially since
1992. Furthermore, new information has become available indicating both
(a) improvements to Snake River water quality, and (b) the ability of
Utah valvata snail to inhabit and persist in reaches of the Snake River
rich in nutrients (e.g., nitrogen and phosphorus).
Factors that are known to degrade water quality in the Snake River
include reduced water flow, warming due to impoundments, and increases
in the concentration of nutrients, sediment, and pollutants reaching
the river from agricultural and aquaculture inputs (USFWS 2005, p.
106). Several water-quality assessments have been completed for the
Snake River by the USEPA, USBR, U.S. Geological Survey (USGS), and IPC.
All of these assessments generally demonstrate that water quality in
the Snake River of southern Idaho meets Idaho's water-quality criteria
for the protection of aquatic life for some months of the year, but may
be poor in reservoirs or during summer high temperatures and low flows,
based on water-quality criteria such as dissolved oxygen (Clark et al.
1998, pp. 20-21, 24-27; Clark et al. 2004, pp. 38-40; Clark and Ott
1996, p. 553; Clark 1997, pp. 1-2, 19; Meitl 2002, p. 33).
Several reaches of the Snake River are classified as water-quality-
impaired due to the presence of one or more pollutants (e.g., Total
Phosphorus (TP), sediments, total coliforms) in excess of State or
Federal guidelines. Nutrient-enriched waters primarily enter the Snake
River via springs, tributaries, fish-farm effluents, municipal waste-
treatment facilities, and irrigation returns (USEPA 2002, pp. 4-18 to
4-24). Irrigation water returned to rivers is
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generally warmer, contains pesticides or pesticide byproducts, has been
enriched with nutrients from agriculture (e.g., nitrogen and
phosphorous), and frequently contains elevated sediment loads.
Pollutants in fish-farm effluent include nutrients derived from
metabolic wastes of the fish and unconsumed fish food, disinfectants,
bacteria, and residual quantities of drugs used to control disease
outbreaks. Elevated levels of fine sediments, nitrogen, and trace
elements (including cadmium, chromium, copper, lead, and zinc) have
been measured immediately downstream of several aquaculture discharges
(Hinson 2003, pp. 42-45). Additionally, concentrations of lead,
cadmium, and arsenic have been detected in snails collected from the
Snake River (Richards 2003). Studies have shown another native Snake
River snail, the Jackson Lake springsnail (Pyrgulopsis robusta), to be
relatively sensitive to copper (a common component in algaecides) and
pentachlorophenol, a restricted use pesticide/wood preservative
(Ingersoll 2006).
The effects of pollutants detected in the Snake River (e.g.,
metals, pesticides, excess nutrients) on the growth, reproduction, and
survival of the Utah valvata snail have not been evaluated. However,
the evidence available to us (including several intensive survey
efforts) does not indicate that the population is declining or that the
range of the species is contracting. Furthermore, the Utah valvata
snail has been documented to occur in low-oxygen, organically-enriched
sediments with heavy macrophyte communities downstream of an
aquaculture facility (RM 588) (Hinson 2003, p. 17), indicating that the
species may not be as sensitive to these pollutants as we once
suspected. Based on the current best available information, we are not
aware that water quality in the Snake River limits growth,
reproduction, or survival of the Utah valvata snail in any portion of
its range.
There have been substantial declines in total dissolved solids
(TSS) primarily as a result of changing irrigation practices. There
have also been substantial declines in TP from changing agricultural
practices and changing aquaculture feeds in the middle Snake River
downstream of Lake Walcott. Data collected by the Idaho Department of
Environmental Quality (IDEQ) show decreases of TSS near 64 percent
compared to 1990 levels, and decreases of TP near 33 percent compared
to 1990 levels (Buhidar 2006). The specific water-quality parameters
required for the survival and persistence of the Utah valvata snails
are not known. However, the Utah valvata snail occurs over a relatively
large documented range of over 255 river miles (410 km) (USFWS 2005,
pp. 110-113) and has the ability to tolerate and persist in a variety
of aquatic habitats with some degree of water-quality degradation
(Lysne and Koetsier 2006b, pp. 234-237). For example, studies conducted
by the USBR in 2003 in Lake Walcott Reservoir indicated the highest
Utah valvata snail densities occurred in the lower reservoir, where the
sediments had the greatest percentage of organic content (an indicator
that oxygen levels are likely low) (Hinson 2006, p. 19).
Summary of Factor A: Our understanding of the habitat needs of the
Utah valvata snail has changed substantially since the species was
listed in 1992. Survey data collected since 1992 indicate that the
geographic range of the species in the Snake River is approximately 122
river miles (196 km) larger than known at the time of listing, that it
occurs in a variety of substrate types (e.g., fines to cobble size) and
flows, and that it tolerates a range of water-quality parameters.
Threats pertaining to the construction of new hydropower dams as cited
in the 1992 final rule have not been realized as the plans for dam
construction have expired or been withdrawn. The operation of existing
hydropower dams and reservoirs likely affect the distribution of the
Utah valvata snail along the shoreline areas due to fluctuating flows
and seasonal dewatering; however, the species appears to persist in
these reservoirs with relatively high proportional occurrence. There is
no information to suggest that degraded water quality is affecting the
species' population numbers or distribution. Evidence indicates that
improvements have been made in Snake River water-quality parameters
including TSS and TP in some Snake River reaches since listing.
Therefore, destruction, modification, or curtailment of the Utah
valvata snail's habitat or range is not currently putting the species
in danger of extinction, and is not likely to result in the
endangerment or extinction of the species in the foreseeable future.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Based on the best available scientific and commercial data, we
believe that overutilization for commercial, recreational, scientific,
or educational purposes is not currently putting the Utah valvata snail
in danger of extinction, and is not likely to result in the
endangerment or extinction of the species in the foreseeable future.
There is no known commercial or recreational use of the species and
collections for scientific or educational purposes are limited in scope
and extent. While collection could result in mortality of individuals
within a small area, they are unlikely to have population-level effects
because only a few individuals and institutions are interested in
collecting the species and the life-history strategy of the species
makes populations relatively resilient to limited mortality (i.e.,
invests little in reproduction, relatively high reproductive output
(many eggs laid at a time), early age of reproduction, and short
lifespan).
Factor C. Disease or Predation
Parasitic trematodes similar to those of the genus Microphallus
have been identified in some freshwater snails (e.g., Pyrgulopsis
robusta) that share similar habitats in the Snake River in Idaho
(Dybdahl et al. 2005, p. 8). However, the occurrence of trematode
parasites on Utah valvata has not been studied.
Predators of the Utah valvata snail have not been documented;
however, we assume that some predation by native and non-native species
occurs. Aquatic snails in general are prey for numerous invertebrates
and vertebrates (Dillon 2000, pp. 274-304), and predation on other
aquatic snails by crayfish and fish is well documented (Lodge et al.
1994, p. 1265; Martin et al. 1992, p. 476; Merrick et al. 1992, p. 225;
Lodge et al. 1998, p. 53; McCarthy and Fisher 2000, p. 387).
Based on the best available scientific and commercial data, we
believe that the threat of disease or predation is not placing the Utah
valvata snail in danger of extinction, and is not likely to result in
the endangerment or extinction of the species in the foreseeable
future. The life-history strategy of the Utah valvata makes populations
relatively resilient to limited mortality due to parasites or disease
(i.e., invests little in reproduction, relatively high reproductive
output (many eggs laid at a time), early age of reproduction, and short
lifespan).
Factor D. Inadequacy of Existing Regulatory Mechanisms
In the final listing rule, we found inadequate regulatory
mechanisms to be a threat because: (1) Regulations were inadequate to
curb further water withdrawal from groundwater spring outflows or
tributary spring streams, (2) it was unlikely that pollution-control
regulations would reverse the trend in nutrient loading any time soon,
(3) there
[[Page 34544]]
was a lack of State-mandated protections for invertebrate species in
Idaho, and (4) regulations did not require FERC or the U.S. Army Corps
of Engineers to address Service concerns regarding licensing
hydroelectric projects or permitting projects under the Clean Water Act
for unlisted snails. Below, we address each of these concerns in turn.
Groundwater Withdrawal Regulations
Since 1992, new information has become available clarifying the
habitat requirements of the Utah valvata snail. The species is not
limited to cool, fast-water, or lotic habitats, or perennial flowing
waters associated with large spring complexes, as previously believed.
The species is able to live in a variety of aquatic habitats, and is
locally abundant throughout a 255-mile (410 km) stretch of the Snake
River in tributary streams, mainstem Snake River, and in reservoirs
that are managed for annual drawdowns.
The Idaho Department of Water Resources (IDWR) manages water in the
State of Idaho. Among the IDWR's responsibilities is the development of
the State Water Plan (IDWR 2006a). The State Water Plan was updated in
1996 and included a table of federally threatened and endangered
species in Idaho, such as the Utah valvata snail. The State Water Plan
outlines objectives for the conservation, development, management, and
optimum use of all unappropriated waters in the State. One of these
objectives is to ``maintain, and where possible enhance water quality
and water-related habitats'' (IDWR 2006a). It is the intent of the
State Water Plan that any water savings realized by conservation or
improved efficiencies is appropriated to other beneficial uses (e.g.,
fish and wildlife, hydropower, or agriculture). Another IDWR regulatory
mechanism is the ability of the Idaho Water Resource Board to
appropriate water for minimum stream flows when in the public interest
(IDWR 2006b).
Since 1992, the IDWR and other State agencies have also created
additional regulatory mechanisms that limit future surface and
groundwater development, including the continuation of various
moratoria on new consumptive water rights and the designation of Water
Management Districts (Caswell 2007). The State is working with numerous
interested parties to stabilize aquifer levels and enhance cold-water-
spring outflows from the Eastern Snake River Plains. The recently
proposed Comprehensive Aquifer Management Plan (CAMP) for the Eastern
Snake River Plains area identifies water conservation measures to be
implemented (Barker et al. 2007). The goal of the CAMP is to ``sustain
the economic viability and social and environmental health of the
Eastern Snake Plain by adaptively managing a balance between water use
and supplies.'' The CAMP will include several alternatives in an
attempt to increase water supply, reduce withdrawals from the aquifer,
and decrease overall demand for groundwater (Barker et al. 2007).
In addition, the State of Idaho established moratoria in 1993 (the
year after listing) that restricted further surface-water and
groundwater withdrawals for consumptive uses from the Snake River Plain
aquifer between American Falls Reservoir and C.J. Strike Reservoir. The
1993 moratoria were extended by Executive Order in 2004 (Caswell 2006,
attachment 1). However, these actions have not yet resulted in
stabilization of aquifer levels. Depletion of spring flows and
declining groundwater levels are a collective effect of drought
conditions, changes in irrigation practices (the use of central-pivot
sprinklers contribute little to groundwater recharge), and groundwater
pumping (University of Idaho 2007). The effects of groundwater pumping
downstream in the aquifer can affect the upper reaches of the aquifer,
and the effects of groundwater pumping can continue for decades after
pumping ceases (University of Idaho 2007).
Thus, we anticipate groundwater levels will likely continue to
decline in the near future, even as water-conservation measures are
implemented, and are being developed. Nevertheless, the extinction or
endangerment of the Utah valvata snail is unlikely given its ability to
survive and persist in a wide variety of aquatic habitats not dependent
upon groundwater outflows.
Pollution Control Regulations
Since 1992, reductions in sediment (TSS) and phosphorus (TP)
loading have improved water quality in localized reaches of the Snake
River (Buhidar 2005) (see Factor A above). Various State-managed water-
quality programs are being implemented within the range of the Utah
valvata snail. These programs are tiered off of the Clean Water Act
(CWA), which requires States to establish water-quality standards that
provide for (1) the protection and propagation of fish, shellfish, and
wildlife, and (2) recreation in and on the water. As required by the
CWA, Idaho has established water-quality standards (e.g., for water
temperature and dissolved oxygen) for the protection of cold-water
biota (e.g., invertebrate species) in many reaches of the Snake River.
The CWA also specifies that States must include an antidegradation
policy in their water quality regulations that protects water-body uses
and high-quality waters. Idaho's antidegradation policy, updated in the
State's 1993 triennial review, is detailed in their Water Quality
Standards (IDEQ 2009).
The IDEQ works closely with the USEPA to manage point and non-point
sources of pollution to water bodies of the State through the National
Pollutant Discharge Elimination System (NPDES) program under the CWA.
IDEQ has not been granted authority by the USEPA to issue NPDES permits
directly, all NPDES permits are issued by the USEPA Region 10 (USEPA
2009). These NPDES permits are written to meet all applicable water-
quality standards established for a water body to protect human health
and aquatic life. Waters that do not meet water-quality standards due
to point and non-point sources of pollution are listed on EPA's 303(d)
list of impaired water bodies. States must submit to EPA a 303(d) list
(water-quality-limited waters) and a 305(b) report (status of the
State's waters) every two years. IDEQ, under authority of the State
Nutrient Management Act, is coordinating efforts to identify and
quantify contributing sources of pollutants (including nutrient and
sediment loading) to the Snake River basin via the Total Maximum Daily
Load (TMDL) approach. In water bodies that are currently not meeting
water-quality standards, the TMDL approach applies pollution-control
strategies through several of the following programs: State
Agricultural Water Quality Program, Clean Water Act section 401
Certification, BLM Resource Management plans, the State Water Plan, and
local ordinances. Several TMDLs have been approved by the EPA in stream
segments within the range of the Utah valvata snail in the Snake River
or its tributaries (Buhidar 2006), although most apply only to TSS, TP,
or temperature.
State Invertebrate Species Regulations
There are no State regulatory protections for the Utah valvata
snail in Idaho. The primary threats to the species, as identified in
our listing rule, were related to the loss or alteration of habitat.
The lack of specific regulations protecting individual Utah valvata
snails does not, by itself, imply that the species is threatened or
endangered.
Federal Consultation Regulations
The discussion regarding the lack of a Federal regulatory mechanism
in the 1992 listing rule was primarily related
[[Page 34545]]
to the proposed construction of six dams within the range of the
species coupled with our belief at the time of listing that the species
required cold, fast-water, or lotic habitats. As stated above, dams are
no longer being proposed for construction and our understanding of Utah
valvata snail habitat requirements has changed. Thus, the importance of
a regulatory mechanism to address these threats is no longer a
significant issue with regard to the conservation of the Utah valvata
snail.
Summary of Factor D: Although there are no specific State
regulations protecting the Utah valvata snail, the primary threats
identified in the final listing rule were related to the loss or
alteration of the species' habitat. Furthermore, as our understanding
of the species' habitat requirements has changed, so has our
understanding of the species' conservation and regulatory needs.
Regulatory mechanisms such as Idaho's water-quality standards and TMDLs
will continue to apply to habitats that the Utah valvata snails occupy
should we finalize this delisting proposal. Therefore, the inadequacy
of existing regulatory mechanisms does not presently endanger the Utah
valvata snail, nor is it likely to do so in the foreseeable future.
Factor E. Other Natural or Manmade Factors Affecting the Species'
Continued Existence
The final listing rule stated that New Zealand mudsnails were not
yet abundant in cold-water spring flows with colonies of the Utah
valvata snail, but that they likely did compete with the species in the
mainstem Snake River habitats (57 FR 59254). Surveys have found that
Utah valvata snails and New Zealand mudsnails frequently co-occur in
cold-water spring, mainstem Snake River, and reservoir habitats (37
percent co-occurrence in combined habitat types), which may indicate
that these two species are able to co-exist or that they actually have
slightly different resource preferences (e.g., periphytic vs.
perilithic algae) (Hinson 2006, p. 42). However, Hinson (2006, p. 41)
also notes that the overlap in habitat utilization between the Utah
valvata snail and the New Zealand mudsnail could lead to direct
competition for resources between these two species.
The USBR reported that New Zealand mudsnails are increasing in Lake
Walcott, yet the densities observed were substantially lower than those
observed in mainstem Snake River habitats downstream (USBR 2003, p. 19,
USBR 2005, p. 6). Further upstream, the distribution of New Zealand
mudsnails currently appears to be limited to the upper end of American
Falls Reservoir near the input of the Snake and Portneuf rivers (USBR
2003, p. 21). Surveys conducted even further upstream in the Snake
River and tributaries (Field 2004, 2005, pp. 8-12) found moderate-to-
high densities of the New Zealand mudsnail at five sites. However,
Field (2005, p. 10) stated that the current distribution of New Zealand
mudsnails in the Snake River above American Falls Reservoir could more
strongly reflect patterns of introductions rather than habitat
preferences. Populations of the New Zealand mudsnail are not known to
occur in the Wood River.
Summary of Factor E: The New Zealand mudsnail frequently co-occurs
with the Utah valvata snail and may be competing for habitat or food.
The New Zealand mudsnail can reach extremely high densities in the
middle Snake River (Richards et al. 2001, p. 375), and has been
recorded at moderate-to-high densities at five sites in tributaries to
the Snake River and the Snake River above American Falls Reservoir.
Populations of the New Zealand mudsnail are not known to occur in the
Wood River. The overall impact on the Utah valvata snail from the
invasion of the New Zealand mudsnail is unknown (Lysne 2003, pp. 85-86;
Hinson 2006, p. 41). However, after approximately 20 years of co-
occurrence there is no evidence suggesting that the New Zealand
mudsnail has caused local extirpations of the Utah valvata snail.
Although this does not rule out potential future effects to the Utah
valvata snail's distribution or abundance, the current evidence does
not support the conclusion that the New Zealand mudsnail presently
endangers the Utah valvata snail, nor that it is likely to do so in the
foreseeable future.
Foreseeable Future
For the purposes of this proposed rule, the ``foreseeable future''
is the period of time over which events or effects reasonably can or
should be anticipated, or trends reasonably extrapolated, such that
reliable predictions can be made concerning the status of the species.
As discussed above in the Summary of Factors section, we determined
that the primary threats that were identified at the time the Utah
valvata snail was listed in 1992 (construction of new, and operation of
existing, hydropower dams; water quality and quantity; inadequacy of
regulatory mechanisms; and the introduction of a new invasive snail
(i.e., the New Zealand mudsnail)) no longer exist (e.g., new dams),
have improved (e.g., water quality), or have not been as severe as
expected (e.g., the New Zealand mudsnail). All indications, based on
our improved understanding of the Utah valvata snail's range, habitat
requirements, and ecology, suggest that the Utah valvata snail is more
widely distributed and occurs in a variety of ecological settings over
a 255-mile (410 km) range of the Snake River. Much of the Snake River
within the range of the Utah valvata is influenced by seasonal dam
operations for hydroelectric or agricultural purposes, yet the species
persists in these varied mainstem Snake River systems, including
impounded reservoir habitats (e.g., Lake Walcott and American Falls
reservoirs). In short, given the available information, we can not
reasonably predict or anticipate that threats to the Utah valvata snail
will increase in severity in the future such that they would lead the
species to become threatened or endangered throughout all or a
significant portion of its range.
Conclusion of the Rangewide 5-Factor Analysis
As required by the Act, we considered the five potential threat
factors to assess whether the Utah valvata snail is threatened or
endangered throughout its range (our analysis of whether there are
significant portions of the species' range that are threatened or
endangered follows this section). Information collected since the
species' listing in 1992 indicates that the Utah valvata snail is
widely distributed and occurs in a variety of ecological settings over
a 255-mile range of the Snake River. Much of the Snake River within the
range of the Utah valvata is influenced by seasonal dam operations for
hydroelectric or agricultural purposes, yet the species persists in
these varied mainstem Snake River systems, including impounded
reservoir habitats (e.g., Lake Walcott and American Falls reservoirs).
None of the threats that we identified in the 1992 listing appear to be
significant to the species in light of our current understanding of its
status. Nor have we identified any other threats to the species.
Therefore, we find that the Utah valvata snail is not in danger of
extinction throughout its range, nor is it likely to become so in the
foreseeable future.
The Service has determined that the original data for
classification of the Utah valvata snail used in 1992 were in error.
However, it is important to note that the original data for
classification constituted the best available scientific and commercial
data available at the time and were in error only in the sense that
they were incomplete. The primary considerations for proposing to
delist
[[Page 34546]]
the Utah valvata snail are described in the five-factor analysis above.
Significant Portion of the Range Analysis
Having determined that the Utah valvata snail does not meet the
definition of a threatened or endangered species throughout its range,
we must next consider whether there are any significant portions of its
range where it is in danger of extinction or is likely to become
endangered in the foreseeable future. On March 16, 2007, a formal
opinion was issued by the Solicitor of the Department of the Interior,
``The Meaning of `In Danger of Extinction Throughout All or a
Significant Portion of Its Range' '' (U.S. DOI 2007). We have
summarized our interpretation of that opinion and the underlying
statutory language below. A portion of a species' range is significant
if it is part of the current range of the species and is important to
the conservation of the species because it contributes meaningfully to
the representation, resiliency, or redundancy of the species. The
contribution must be at a level such that its loss would result in a
decrease in the ability to conserve the species.
The first step in determining whether a species is threatened or
endangered in a significant portion of its range is to identify any
portions of the range of the species that warrant further
consideration. The range of a species can theoretically be divided into
portions in an infinite number of ways. However, there is no purpose to
analyzing portions of the range that are not reasonably likely to be
significant and threatened or endangered. To identify only those
portions that warrant further consideration, we determine whether there
is substantial information indicating that (i) the portions may be
significant and (ii) the species may be in danger of extinction there
or likely to become so within the foreseeable future. In practice, a
key part of this analysis is whether the threats are geographically
concentrated in some way. If the threats to the species are essentially
uniform throughout its range, no portion is likely to warrant further
consideration. Moreover, if any concentration of threats applies only
to portions of the range that are unimportant to the conservation of
the species, such portions will not warrant further consideration.
If we identify any portions of a species' range that warrant
further consideration, we then determine whether in fact the species is
threatened or endangered in any significant portion of its range.
Depending on the biology of the species, its range, and the threats it
faces, it may be more efficient in some cases for the Service to
address the significance question first, and in others the status
question first. Thus, if the Service determines that a portion of the
range is not significant, the Service need not determine whether the
species is threatened or endangered there; conversely, if the Service
determines that the species is not threatened or endangered in a
portion of its range, the Service need not determine if that portion is
significant.
The terms ``resiliency,'' ``redundancy,'' and ``representation''
are intended to be indicators of the conservation value of portions of
the species' range. Resiliency of a species allows the species to
recover from periodic disturbance. A species will likely be more
resilient if large populations exist in high-quality habitat that is
distributed throughout the range of the species in such a way as to
capture the environmental variability within the range of the species.
It is likely that the larger size of a population will help contribute
to the viability of the species. Thus, a portion of the range of a
species may make a meaningful contribution to the resiliency of the
species if the area is relatively large and contains particularly high-
quality habitat or if its location or characteristics make it less
susceptible to certain threats than other portions of the range. When
evaluating whether or how a portion of the range contributes to
resiliency of the species, it may help to evaluate the historical value
of the portion and how frequently the portion is used by the species.
In addition, the portion may contribute to resiliency for other
reasons--for instance, it may contain an important concentration of
certain types of habitat that are necessary for the species to carry
out its life-history functions, such as breeding, feeding, migration,
dispersal, or wintering.
Redundancy of populations may be needed to provide a margin of
safety for the species to withstand catastrophic events. This does not
mean that any portion that provides redundancy is a significant portion
of the range of a species. The idea is to conserve enough areas of the
range such that random perturbations in the system act on only a few
populations. Therefore, each area must be examined based on whether
that area provides an increment of redundancy that is important to the
conservation of the species.
Adequate representation insures that the species' adaptive
capabilities are conserved. Specifically, the portion should be
evaluated to see how it contributes to the genetic diversity of the
species. The loss of genetically based diversity may substantially
reduce the ability of the species to respond and adapt to future
environmental changes. A peripheral population may contribute
meaningfully to representation if there is evidence that it provides
genetic diversity due to its location on the margin of the species'
habitat requirements.
Applying the process described above we evaluated a recent genetic
study of the Utah valvata snail (Miller et al. 2006) and the ecological
settings in which the species occurs throughout its range. We divided
the range into three population units for further analysis: The Wood
River population unit, the Snake River population unit, and the
Hagerman population unit. Both the Wood River and Hagerman populations
are separated geographically, and in the case of the Hagerman
population, genetically and ecologically. Geographically, the Upper
Snake and Henry's Fork Rivers and reservoirs of the Snake River are
proximal and have a greater potential for connectivity of the Utah
valvata snail populations in these reaches. They were analyzed as one
unit: the Snake River population unit. We then evaluated whether each
unit constitutes a significant portion of the range of the species, and
if so, whether that portion was threatened or endangered.
Wood River Population Unit
There is a high degree of uncertainty concerning the distribution
and abundance of the species in the Wood River since there has been
only one documented colony and systematic surveys have not been
conducted. Based on the limited information we have on the Utah valvata
snail in the Wood River, this colony does not appear to exist in an
unusual or unique ecological setting or contain a large portion of the
habitat or individuals (in fact, it appears to constitute an extremely
small portion of the overall habitat and number of individuals).
Further, recent genetic work conducted by Miller et al. (2006, pp.
2367-2372) found that the Wood River occurrence is not genetically
divergent or unique from the Snake River population unit. Because of
genetic similarities between Utah valvata snails in the Snake River and
Wood River units, the Wood River unit could provide some redundancy to
the species if the Snake River unit (see below for further information)
is extirpated by a catastrophic event. However, given that Utah valvata
are distributed discontinuously along 255 miles (410 km) of the Snake
River unit, a catastrophic event of the magnitude
[[Page 34547]]
necessary to simultaneously eliminate all Utah valvata colonies from
the Snake River unite is highly unlikely. In addition, due to the
geographic separation of the Wood River unit from the Snake River unit,
it is unlikely that the Wood River unit would be a significant source
of snails to recolonize the Snake River. Therefore, given these
factors, we determined the Wood River population unit did not provide a
significant contribution to the species with regard to redundancy,
resiliency, and representation, and was not evaluated further.
Snake River Population Unit
The Snake River population unit contains the largest and widest
ranging portion of the overall Utah valvata snail population and
contributes substantially to the resiliency, representation, and
redundancy of the species. As mentioned above, the Snake River
population was analyzed as one unit because the Upper Snake and Henry's
Fork Rivers and reservoirs of the Snake River are proximal and have a
greater potential for connectivity of the Utah valvata populations in
these reaches. Other information contributing to its significance
includes: (1) Additional surveys in this unit would likely find more
colonies of Utah valvata snail, since most surveys conducted since 1992
have been project based and systematic surveys have not yet occurred
throughout much of this reach; (2) the uppermost reaches of the Snake
River unit, including the Henry's Fork River where Utah valvata snail
occurs, is not influenced by dam and other water management operations,
and water quality is considered to be better than that found in the
Wood River or Hagerman reaches further downstream in the Snake River;
(3) Lower Lake Walcott Reservoir has high densities and high
proportional occurrence of the Utah valvata snail and likely provides
refugia for the species primarily due to the human-induced stability of
this reservoir environment; and (4) genetically, the Snake River
population unit represents the ancestral haplotypes of this species
(Miller et al. 2006, p. 2368).
For all of these reasons, we determined that the Snake River
population unit of the Utah valvata snail constitutes a significant
portion of the species' range. The Snake River population unit was then
evaluated to determine if the Utah valvata snail is threatened or
endangered in this portion of its range. This unit covers a wide
geographic range and provides a wide variety of suitable habitats for
Utah valvata snail in both reservoir and riverine reaches. This unit
likely contains the largest number of individuals and colonies of the
Utah valvata snail and would likely sustain the species into the
foreseeable future independent of the other population units.
Water quality is relatively good in the upstream (Henry's Fork)
reaches of this unit compared to other population units, and the New
Zealand mudsnail has not become established throughout this unit.
Therefore, in the context of new information regarding the species'
habitat and ecology, we likewise conclude that the Snake River
population unit of Utah valvata snail is not threatened or endangered.
Hagerman Population Unit
The best available data indicate that the Hagerman population unit
is likely isolated and separated geographically from other Utah valvata
snail colonies further upstream that constitute the Snake River
population unit, but overall represents a small area of occupancy
compared to the rest of the range of the species. The geographic
isolation of the Hagerman population unit is an important
consideration; the Miller et al. (2006) genetics paper suggests that
Utah valvata snails found in cold-water spring outflows at the Thousand
Springs Preserve may have been genetically isolated for over 10,000
years and should be evaluated to determine if they can reproduce with
other Utah valvata snails elsewhere in their range. This population
unit also has a unique ecological setting compared to the other two
units, as the species mainly occurs in tributary springs (and at their
cold-water outflows), and not in reservoir or riverine habitats.
In light of the above, we concluded that the Hagerman population
unit may constitute a significant portion of the range of the Utah
valvata snail. To determine if the Utah valvata snail is either
threatened or endangered in this portion of the range, we evaluated the
threat factors of water quality and effects, current hydropower
operations, and the New Zealand mudsnail, and potential for other
invasive species effects in the future.
Currently, water quality is not considered to be a threat that is
of high severity or magnitude to the Hagerman population unit for the
reasons outlined in Factor A of the rangewide analysis. Furthermore,
two cold-water spring outflows, Box Canyon and Thousand Springs,
provide a relatively high-quality and stable aquatic environment for
some Utah valvata snail colonies. Although flows have recently declined
in some cold-water springs due to groundwater withdrawals, and water
quantity and quantity could decrease over time if flows are not
preserved, the Utah valvata snail would continue to persist in the
mainstem Snake River in the Hagerman reach where it can tolerate
variable water temperatures and water quality. Although there is
evidence of some density-dependent effects and competition where the
New Zealand mudsnail co-occurs with the Utah valvata snail, the Utah
valvata snail continues to persist in these habitats. Despite
approximately 20 years of co-occurrence of the New Zealand mudsnail and
Utah valvata snail, there is no evidence suggesting that the New
Zealand mudsnail has caused local extirpations of the Utah valvata
snail in Hagerman reach. Therefore, we conclude that the Hagerman
population unit of the Utah valvata snail is not threatened or
endangered in this portion of its range.
In summary, our understanding of the Utah valvata snail's habitat
requirements, range, and threats has changed since the time of listing.
From studies conducted since 1992, we now know that the species occurs
over a much larger geographic range in the Snake River and is able to
live in a variety of aquatic habitats and is not limited to cold, fast-
water, or lotic habitats, or in perennial flowing waters associated
with large spring complexes as previously believed. In addition, the
proposed construction of six new hydropower facilities as discussed at
the time of listing is no longer a threat. The Utah valvata snail is
now known to occur in, and persist in, aquatic habitats influenced by
dam operations (e.g., reservoirs, and at elevated water temperatures),
and the species co-exists in a variety of Snake River aquatic habitats
with the invasive New Zealand mudsnail. We have determined that none of
the existing or potential threats, either alone or in combination with
others, are likely to cause the Utah valvata snail to become in danger
of extinction within the foreseeable future throughout all or any
significant portion of its range. The Utah valvata snail no longer
requires the protection of the Act, and, therefore, we are proposing to
remove it from the Federal List of Endangered and Threatened Wildlife.
Effects of This Rule
If made final, this rule would revise 50 CFR 17.11(h) to remove the
Utah valvata snail from the Federal List of Endangered and Threatened
Wildlife. The prohibitions and conservation measures provided by the
Act, particularly through sections 7 and 9, would no longer apply to
this species.
[[Page 34548]]
Federal agencies would no longer be required to consult with the
Service under section 7 of the Act in the event that activities they
authorize, fund, or carry out may affect the Utah valvata snail. There
is no critical habitat designated for this species.
Peer Review
In accordance with our joint policy published in the Federal
Register on July 1, 1994 (59 FR 34270), we will seek the expert
opinions of at least three appropriate and independent specialists
regarding this proposed rule. The purpose of such review is to ensure
that our proposed rule is based on scientifically sound data,
assumptions, and analyses. We will send peer reviewers copies of this
proposed rule immediately following publication in the Federal Register
and will invite them to comment, during the public comment period, on
the specific assumptions and conclusions regarding the proposal to
delist the Utah valvata snail. We will consider all comments and
information received during the comment period on this proposed rule
during preparation of a final rulemaking. Accordingly, the final
decision may differ from this proposal.
Public Hearings
Section 4(b)(5)(D) of the Act requires that we hold one public
hearing on this proposal, if requested. Requests must be received
within 45 days of the date of publication of the proposal in the
Federal Register (see DATES). Such requests must be made in writing and
be addressed to the State Supervisor at the address in the FOR FURTHER
INFORMATION CONTACT section above.
Clarity of This Proposed Rule
We are required by Executive Orders 12866 and 12988 and by the
Presidential Memorandum of June 1, 1998, to write all rules in plain
language. This means that each rule we publish must:
(a) Be logically organized;
(b) Use the active voice to address readers directly;
(c) Use clear language rather than jargon;
(d) Be divided into short sections and sentences; and
(e) Use lists and tables wherever possible.
If you feel that we have not met these requirements, send us
comments by one of the methods listed in the ADDRESSES section. To
better help us revise the rule, your comments should be as specific as
possible. For example, you should tell us the numbers of the sections
or paragraphs that are unclearly written, which sections or sentences
are too long, the sections where you feel lists or tables would be
useful, etc.
Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.)
This rule does not contain any new collections of information that
require approval by OMB under the Paperwork Reduction Act. This rule
will not impose recordkeeping or reporting requirements on State or
local governments, individuals, businesses, or organizations. An agency
may not conduct or sponsor, and a person is not required to respond to,
a collection of information unless it displays a currently valid OMB
control number.
National Environmental Policy Act
We have determined that environmental assessments and environmental
impact statements, as defined under the authority of the National
Environmental Policy Act of 1969, need not be prepared in connection
with regulations adopted pursuant to section 4(a) of the Act. We
published a notice outlining our reasons for this determination in the
Federal Register on October 25, 1983 (48 FR 49244).
References Cited
A complete list of all references cited herein is available upon
request from the Idaho Fish and Wildlife Office (see ADDRESSES).
Author
The primary author of this document is the Idaho Fish and Wildlife
Office (see ADDRESSES).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, and Transportation.
Proposed Regulation Promulgation
Accordingly, we propose to amend part 17, subchapter B of chapter
I, title 50 of the Code of Federal Regulations, as set forth below:
PART 17--[AMENDED]
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.
4201-4245; Pub. L. 99-625, 100 Stat. 3500, unless otherwise noted.
Sec. 17.11 [Amended]
2. Section 17.11(h) is amended by removing the entry for ``Snail,
Utah valvata'' under ``SNAILS'' from the List of Endangered and
Threatened Wildlife.
Dated: July 7, 2009.
James J. Slack,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. E9-16837 Filed 7-15-09; 8:45 am]
BILLING CODE 4310-55-P