[Federal Register Volume 64, Number 75 (Tuesday, April 20, 1999)]
[Rules and Regulations]
[Pages 19300-19309]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-9935]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
RIN 1018-AF59
Endangered and Threatened Wildlife and Plants; Emergency Rule To
List the Sierra Nevada Distinct Population Segment of California
Bighorn Sheep as Endangered
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Emergency rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), exercise our
authority to emergency list the Sierra Nevada distinct population
segment of California bighorn sheep (Ovis canadensis californiana),
occupying the Sierra Nevada of California, as endangered under the
Endangered Species Act of 1973, as amended (Act). The Sierra Nevada
bighorn sheep is known from five disjunct subpopulations along the
eastern escarpment of the Sierra Nevada totaling about 100 animals.
All five subpopulations are very small and are imminently
threatened by mountain lion (Puma concolor) predation and disease.
Because these threats constitute an emergency posing a significant risk
to the well-being of the Sierra Nevada bighorn sheep, we find that
emergency listing is necessary. This emergency rule provides Federal
protection pursuant to the Act for this species for a period of 240
days. A proposed rule to list the Sierra Nevada bighorn sheep as
endangered is published concurrently with this emergency rule in this
same issue of the Federal Register in the proposed rule section.
DATES: This emergency rule becomes effective immediately upon
publication and expires December 16, 1999.
ADDRESSES: The complete file for this rule is available for inspection,
by appointment, during normal business hours at the U.S. Fish and
Wildlife Service, Ventura Fish and Wildlife Office, 2493 Portola Rd.
Suite B, Ventura, California 93003.
FOR FURTHER INFORMATION CONTACT: Carl Benz, at the address listed above
(telephone 805/644-1766; facsimile 805/644-3958).
Background
The bighorn sheep (Ovis canadensis) is a large mammal (family
Bovidae) originally described by Shaw in 1804 (Wilson and Reeder 1993).
Several subspecies of bighorn sheep have been recognized on the basis
of geography and differences in skull measurements (Cowan 1940;
Buechner 1960). These subspecies of bighorn sheep, as described in
these early works, include O. c. cremnobates (Peninsular bighorn
sheep), O. c. nelsoni (Nelson bighorn sheep), O. c. mexicana (Mexican
bighorn sheep), O. c. weemsi (Weems bighorn sheep), O. c. californiana
(California bighorn sheep), and O. c. canadensis (Rocky Mountain
bighorn sheep). However, recent genetic studies question the validity
of some of these subspecies and suggest a need to re-evaluate overall
bighorn sheep taxonomy. For example, Sierra Nevada bighorn sheep appear
to be more closely related to desert bighorn sheep than the O. c.
californiana found in British Columbia (Ramey 1991, 1993). Regardless,
the Sierra Nevada bighorn sheep meets our criteria for consideration as
a distinct vertebrate population segment (as discussed below) and is
treated as such in this emergency rule.
The historical range of the Sierra Nevada bighorn sheep (Ovis
canadensis californiana) includes the eastern slope of the Sierra
Nevada, and, for at least one subpopulation, a portion of the western
slope, from Sonora Pass in Mono County south to Walker Pass in Kern
County, a total distance of about 346 kilometers (km) (215 miles (mi))
(Jones 1950; Wehausen 1979, 1980). By the turn of the century, about 10
out of 20 historical subpopulations survived. The number dropped to
five subpopulations at mid-century, and down to two subpopulations in
the 1970s, near Mount Baxter and Mount Williamson in Inyo County
(Wehauser 1979). Currently, five subpopulations of Sierra Nevada
bighorn sheep occur at Lee Vining Canyon, Wheeler Crest, Mount Baxter,
Mount Williamson, and Mount Langley in Mono and Inyo counties, three of
which are reintroduced subpopulations established from sheep obtained
from the Mount Baxter subpopulation from 1979 to 1986 (Wehausen et al.
1987).
The Sierra Nevada bighorn sheep is similar in appearance to other
desert associated bighorn sheep. The species' pelage shows a great deal
of color variation, ranging from almost white to dark brown, with a
white rump. Males and females have permanent horns; the horns are
massive and coiled in males, and are smaller and not coiled in females
(Jones 1950; Buechner 1960). As the animals age, their horns become
rough and scarred with age, and will vary in color from yellowish-brown
to dark brown. In comparison to many other desert bighorn sheep, the
horns of the Sierra Nevada bighorn sheep are generally more divergent
as they coil out from the base (Wehausen 1983). Adult male sheep stand
up to a meter (m) (3 feet (ft)) tall at the shoulder; males weigh up to
99 kilograms (kg) (220 pounds (lbs)) and females 63 kg (140 lbs)
(Buechner 1960).
The current and historical habitat of the Sierra Nevada bighorn
sheep is almost entirely on public land managed by the U.S. Forest
Service (USFS), Bureau of Land Management (BLM), and National Park
Service (NPS). The Sierra Nevada is located along the eastern boundary
of California, and peaks vary
[[Page 19301]]
in elevation from 1825 to 2425 (m) (6000 to 8000 ft) in the north, to
over 4300 m (14,000 ft) in the south adjacent to Owens Valley, and then
drop rapidly in elevation in the southern extreme end of the range
(Wehausen 1980). Most precipitation, in the form of snow, occurs from
October through April (Wehausen 1980).
Sierra Nevada bighorn sheep inhabit the alpine and subalpine zones
during the summer, using open slopes where the land is rough, rocky,
sparsely vegetated and characterized by steep slopes and canyons
(Wehausen 1980: Sierra Nevada Bighorn Sheep Interagency Advisory Group
(Advisory Group) 1997). Most of these sheep live between 3,050 and
4,270 m (10,000 and 14,000 ft) in elevation in summer (John Wehausen,
University of California, White Mountain Research Station, pers. comm.
1999). In winter, they occupy high, windswept ridges, or migrate to the
lower elevation sagebrush-steppe habitat as low as 1,460 m (4,800 ft)
to escape deep winter snows and find more nutritious forage. Bighorn
sheep tend to exhibit a preference for south-facing slopes in the
winter (Wehausen 1980). Lambing areas are on safe steep, rocky slopes.
They prefer open terrain where they are better able to see predators.
For these reasons, they usually avoid forests and thick brush if
possible (J. Wehausen, pers. comm. 1999).
Bighorn sheep are primarily diurnal, and their daily activity show
some predictable patterns that consists of feeding and resting periods
(Jones 1950). Bighorn sheep are primarily grazers, however, they may
browse woody vegetation when it is growing and very nutritious. They
are opportunistic feeders selecting the most nutritious diet from what
is available. Plants consumed include varying mixtures of graminoids
(grasses), browse (shoots, twigs, and leaves of trees and shrubs), and
herbaceous plants depending on season and location (Wehausen 1980). In
a study of the Mount Baxter and Mount Williamson subpopulations,
Wehausen (1980) found that grass, mainly Stipa speciosa (perennial
needlegrass), is the primary diet item in winter. As spring green-up
progresses, the bighorn sheep shift from grass to a more varied browse
diet, which includes Ephedra viridis (Mormon tea), Eriogonum
fasciculatum (California buckwheat), and Purshia species (bitterbrush).
Sierra Nevada bighorn sheep are gregarious, with group size and
composition varying with gender and from season to season. Spatial
segregation of males and females occurs outside the mating season, with
males more than 2 years old living apart from females and younger males
for most of the year (Jones 1950; Cowan and Geist 1971; Wehausen 1980).
Ewes generally remain all their lives in the same band into which they
were born (Cowan and Geist 1971). During the winter, Sierra Nevada
bighorn sheep concentrate in those areas suitable for wintering,
preferably Great Basin habitat (sagebrush steppe) at the very base of
the eastern escarpment. Subpopulation size can number more than 100
sheep, including rams (this was observed at a time when the population
size was larger than it is currently) (J. Wehausen, pers. comm. 1999).
By summer, these subpopulations decrease in size as more habitat
becomes available. Breeding takes place in the fall, generally in
November (Cowan and Geist 1971). Single births are the norm for North
American wild sheep, but twinning is known to occur (Wehausen 1980).
Gestation is about 6 months (Cowan and Geist 1971).
Lambing occurs between late April to early July, with most lambs
born in May or June (Wehausen 1980, 1996). Ewes with newborn lambs live
solitarily for a short period before joining nursery groups that
average about six sheep. Ewes and lambs frequently occupy steep terrain
that provides a diversity of slopes and exposures for escape cover.
Lambs are precocious, and within a day or so, climb almost as well as
the ewes. Lambs are able to eat vegetation within 2 weeks of their
birth and are weaned between 1 and 7 months of age. By their second
spring, they are independent of their mothers. Female lambs stay with
ewes indefinitely and may attain sexual maturity during the second year
of life. Male lambs, depending upon physical condition, may also attain
sexual maturity during the second year of life (Cowan and Geist 1971).
Average lifespan is 9 to 11 years in both sexes, though some rams are
known to have lived 12 to 14 years (Cowan and Geist 1971; Wehausen
1980).
Distinct Vertebrate Population Segment
Recent analyses of bighorn sheep genetics and morphometrics (size
and shape of body parts) suggest reevaluation of the taxonomy of Sierra
Nevada bighorn sheep (Ovis canadensis californiana) is necessary (Ramey
1991, 1993,1995; Wehausen and Ramey 1993, 1998). A recent analysis of
the taxonomy of bighorn sheep using morphometrics (e.g., size and shape
of skull components) failed to support the current taxonomy (Wehausen
and Ramey 1993). However, this and other research (Ramey 1993) support
taxonomic distinction of the Sierra Nevada bighorn sheep relative to
other nearby regions.
The biological evidence supports recognition of Sierra Nevada
bighorn sheep as a distinct vertebrate population segment for purposes
of listing, as defined in our February 7, 1996, Policy Regarding the
Recognition of Distinct Vertebrate Population Segments (61 FR 4722).
The definition of ``species'' in section 3(16) of the Endangered
Species Act of 1973, as amended (Act) (16 U.S.C. 1531 et seq.) includes
``any distinct population segment of any species of vertebrate fish or
wildlife which interbreeds when mature.'' For a population to be listed
under the Act as a distinct vertebrate population segment, three
elements are considered--(1) the discreteness of the population segment
in relation to the remainder of the species to which it belongs; (2)
the significance of the population segment to the species to which it
belongs; and (3) the population segment's conservation status in
relation to the Act's standards for listing (i.e., is the population
segment endangered or threatened?) (61 FR 4722).
The distinct population segment (DPS) of bighorn sheep in the
Sierra Nevada is discrete in relation to the remainder of the species
as a whole. This DPS is geographically isolated and separate from other
California bighorn sheep. There is no mixing of this population with
other bighorn sheep, and this is supported by evaluation of the
population's genetic variability and morphometric analysis of skull and
horn variation (Ramey 1993, 1995; Wehausen and Ramey 1993, 1994;
Wehausen and Ramey 1999 (in review)). Researchers suggest that all
other populations of O. c. californiana be reassigned to other
subspecies, leaving O. c. californiana (i.e., the DPS that is the
subject of this rule) only in the central and southern Sierra Nevada
(Ramey 1993, 1995; Wehausen and Ramey 1993, 1994; Wehausen and Ramey
1999 (in review)).
Sierra Nevada bighorn sheep DPS is biologically and ecologically
significant to the species to which it belongs in that it constitutes
the only population of California bighorn sheep inhabiting the Sierra
Nevada. This DPS extends from Sonora Pass to Walker Pass, and spans
approximately 346 km (215 mi) of contiguous suitable habitat in the
United States. The loss of Sierra Nevada bighorn sheep would result in
the total extirpation of bighorn sheep from the Sierra Nevada in
California.
[[Page 19302]]
Status and Distribution
Historically, bighorn sheep populations occurred along and east of
the Sierra Nevada crest from Sonora Pass (Mono County) south to Walker
Pass (Olancha Peak) (Kern County) (Jones 1950; Wehausen 1979). Sheep
apparently occurred wherever appropriate rocky terrain and winter range
existed. With some exception, most of the populations wintered on the
east side of the Sierra Nevada and spent summers near the crest
(Wehausen 1979).
Subpopulations of Sierra Nevada bighorn sheep probably began
declining with the influx of gold miners to the Sierra Nevada in the
mid-1880s, and those losses have continued through the 1900s (Wehausen
1988). By the 1970s, only 2 subpopulations of Sierra Nevada bighorn
sheep, those near Mount Baxter and Mount Williamson in Inyo County, are
known to have survived (Wehausen 1979). Specific causes for the
declines are unknown. Market hunting may have been a contributing
factor as evidenced by menus from historic mining towns such as Bodie,
which included bighorn sheep (Advisory Group 1997). However, with the
introduction of domestic sheep in the 1860s and 1870s, wild sheep are
known to have died in large numbers in several areas from disease
contracted from domestic livestock (Jones 1950; Buechner 1960). Large
numbers of domestic sheep were grazed seasonally in the Owens Valley
and Sierra Nevada prior to the turn of the century (Wehausen 1988), and
disease is believed to be the factor most responsible for the
disappearance of bighorn sheep subpopulations in the Sierra Nevada.
Jones (1950) suggested that scabies was responsible for a die-off in
the 1870s on the Great Western Divide. Experiments have confirmed that
bacterial pneumonia (Pasteurella species), carried normally by domestic
sheep, can be fatal to bighorn sheep (Foreyt and Jessup 1982).
By 1979, only 220 sheep were known to exist in the Mount Baxter
subpopulation, and 30 in the Mount Williamson subpopulation (Wehausen
1979). Conservation efforts by several Federal and State agencies from
1970 to 1988 were aimed at expanding the distribution of Sierra Nevada
bighorn sheep by translocating sheep back into historical habitat.
Sheep were obtained from the Mount Baxter subpopulation and
transplanted to three historic locations. Consequently, Sierra Nevada
bighorn sheep now occur in five subpopulations in Mono and Inyo
counties: Lee Vining Canyon, Wheeler Crest, Mount Baxter, Mount
Williamson, and Mount Langley. The Sierra Nevada bighorn sheep
population reached a high of about 310 in 1985-86. Subsequently,
population surveys have documented a declining trend (J. Wehausen,
pers. comm. 1999).
The following table best represents the total Sierra Nevada bighorn
sheep population over various time periods. These totals represent the
numbers of sheep emerging from winter in each of these years, and best
document the status of the population by incorporating winter
mortality, especially of lambs born the previous year. These totals are
not absolute values; numbers have been rounded to the nearest five (J.
Wehausen, pers. comm. 1999). The continuing decline of the Sierra
Nevada bighorn sheep has been attributed to a combination of the direct
and indirect effects of predation (Wehausen 1996).
Table 1. Sierra Nevada Bighorn Sheep Population Numbers, by Year (J.
Wehausen, Pers. Comm. 1999)
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Number of Total
Year populations sheep
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1978............................................. 2 250
1985............................................. 4 310
1995............................................. 5 100
1996............................................. 5 110
1997............................................. 5 130
1998............................................. 5 100
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Previous Federal Action
In our September 18, 1985, Notice of Review, we designated the
Sierra Nevada bighorn sheep as a category 2 candidate and solicited
status information (50 FR 37958). Category 2 candidates were those taxa
for which we had information indicating that proposing to list as
endangered or threatened was possibly appropriate, but for which
sufficient data on biological vulnerability and threats were not
currently available to support a proposed rule. Category 1 taxa were
those taxa for which we had sufficient information on file to support
issuance of proposed listing rules. In our January 6, 1989 (54 FR 554),
and November 21, 1991 (56 FR 58804), Notices of Review, we retained the
Sierra Nevada bighorn sheep in category 2. Beginning with our February
28, 1996, Notice of Review (61 FR 235), we discontinued the designation
of multiple categories of candidates, and we now consider only taxa
that meet the definition of former category 1 as candidates for
listing. At this point, the Sierra Nevada bighorn sheep was identified
as a species of concern.
The processing of this emergency rule conforms with our listing
priority guidance published in the Federal Register on May 8, 1998 (63
FR 25502). This guidance clarifies the order in which we will process
rulemakings giving highest priority (Tier 1) to processing emergency
listings and second highest priority (Tier 2) to resolving the listing
status of outstanding proposed listings, resolving the conservation
status of candidate species, processing administrative findings on
petitions to add species to the lists or reclassify species from
threatened to endangered status, and delisting or reclassifying
actions. The lowest priority actions, processing critical habitat
designations, are in Tier 3. This emergency rule constitutes a Tier 1
action.
Summary of Factors Affecting the Species
After a thorough review and consideration of all information
available, we have determined that the Sierra Nevada bighorn sheep
warrants classification as an endangered distinct population segment.
We followed procedures found at section 4 of the Act and regulations
(50 CFR part 424) promulgated to implement the listing provisions of
the Act. We may determine a species to be endangered or threatened due
to one or more of the five factors described in section 4(a)(1). These
factors, and their application to the Sierra Nevada bighorn sheep
distinct population segment (Ovis canadensis californiana), are as
follows:
A. The present or threatened destruction, modification, or
curtailment of its habitat or range. Habitat throughout the historic
range of Sierra Nevada bighorn sheep remains essentially intact; the
habitat is neither fragmented nor degraded. However, by 1900, about
half of the Sierra Nevada bighorn sheep populations were lost, most
likely because of introduction of diseases by domestic livestock, and
illegal hunting (Advisory Group 1997). Beginning in 1979, animals from
the Mount Baxter subpopulation were translocated to reestablish
subpopulations in Lee Vining Canyon, Wheeler Crest, and Mount Langley
in Mono and Inyo counties (Advisory Group 1997). Currently, Sierra
Nevada bighorn sheep are limited to five subpopulations. Almost all of
the historical and current habitat is administered by either the USFS,
BLM, or NPS. Some small parcels of inholdings within the species' range
are owned by the Los Angeles Department
[[Page 19303]]
of Water and Power. Also, there are some patented mining claims in
bighorn sheep habitat, but the total acreage is small.
B. Overutilization for commercial, recreational, scientific, or
educational purposes. During the period of the California gold rush
(starting about 1849), hunting to supply food for mining towns may have
played a role in the decline of the population (Wehausen 1988). Besides
being sought as food, Sierra Nevada bighorn sheep were also killed by
sheepmen who considered wild sheep as competitors for forage with
domestic sheep. The decimation of several wildlife species in the late
1800s prompted California to pass legislation providing protection to
deer, elk, pronghorn antelope, and bighorn sheep (Jones 1950; Wehausen
1979).
Commercial and recreational hunting of Sierra Nevada bighorn sheep
is not permitted under State law. There is no evidence that other
commercial, recreational, scientific, or educational activities are
currently a threat. Poaching does not appear to be a problem at this
time.
C. Disease or predation. Disease is believed to have been the major
contributing factor responsible for the precipitous decline of Sierra
Nevada bighorn sheep starting in the late 1800s (Foreyt and Jessup
1982).
Bighorn sheep are host to a number of internal and external
parasites, including ticks, lice, mites, tapeworms, roundworms, and
lungworms. Most of the time, parasites are present in relatively low
numbers and have little effect on individual sheep and populations
(Cowan and Geist 1971).
Cattle were first introduced into the Sierra Nevada in 1860s but
were replaced with domestic sheep that could graze more extensively
over the rugged terrain (Wehausen et al. 1987; Wehausen 1988). Large
numbers of domestic sheep were grazed seasonally in the Sierra Nevada
prior to the turn of the century, and the domestic sheep would use the
same ranges as the wild sheep, occasionally coming into direct contact
with them. Both domestic sheep and cattle can act as disease
reservoirs. Scabies, most likely contracted from domestic sheep, caused
a major decline of bighorn sheep in California in the 1870s to the
1890s and caused catastrophic die-offs in other parts of their range
(Buechner 1960). A die-off of bighorn sheep in the 1870s on the Great
Western Divide (Mineral King area of Sequoia National Park) was
attributed to scabies, presumably contracted from domestic sheep (Jones
1950).
Die-offs from pneumonia contracted from domestic sheep is another
important cause of losses. In 1988, a strain of pneumonia, apparently
contracted from domestic sheep, wiped out a reintroduced herd of
bighorn sheep in Modoc County. Native bighorn sheep cannot tolerate
strains of respiratory bacteria, such as Pasteurella species, carried
normally by domestic sheep and close contact with domestic animals
results in transmission of disease and subsequent deaths of the exposed
animals (Foreyt and Jessup 1982). Bighorn sheep can also develop
pneumonia independent of contact with domestic sheep. Lungworms of the
genus Protostrongylus are often an important contributor to the
pneumonia disease process in some situations (J. Wehausen, pers. comm.
1999). Lungworms are carried by an intermediate host snail, which is
ingested by a sheep as it is grazing. Lungworm often exists in a
population, but usually doesn't cause a problem. However, if the sheep
are stressed in some way, they may develop bacterial pneumonia, which
is complicated by lungworm infestation. Bacterial pneumonia is usually
a sign of weakness caused by some other agent such as a virus,
parasite, poor nutrition, predation, human disturbance, or
environmental or behavioral stress that lowers the animal's resistance
to disease (Wehausen 1979; Foreyt and Jessup 1982). Bighorn sheep in
the Sierra Nevada carry Protostrongylus species (lungworms), but the
parasite loads have been low, and there has been no evidence of any
clinical signs of disease or disease transmission (Wehausen 1979;
Richard Perloff, Inyo National Forest, pers. comm. 1999).
Currently, domestic sheep grazing allotments are permitted by the
U.S. Forest Service in areas adjacent to Sierra Nevada bighorn sheep
subpopulations. Domestic sheep occasionally escape the allotments and
wander into bighorn sheep areas, sometimes coming into direct contact
with bighorn sheep (Advisory Group 1997). For example, in 1995, 22
domestic sheep that were permitted on USFS land wandered away from the
main band and were later found in Yosemite National Park, after
crossing through occupied bighorn sheep habitat (Advisory Group 1997;
Bonny Pritchard, Inyo National Forest, pers. comm. 1999; R. Perloff,
pers. comm. 1999). Other stray domestic sheep, in smaller numbers, have
been known to wander up the road in Lee Vining Canyon into bighorn
sheep habitat (B. Pritchard, pers. comm. 1999). Based on available
information, and given the susceptibility of bighorn sheep to
introduced pathogens, disease will continue to pose a significant and
underlying threat to the survival of Sierra Nevada bighorn sheep until
the potential for contact with domestic sheep is eliminated.
Predators such as coyote (Canis latrans), bobcat (Lynx rufus),
mountain lion, gray fox (Urocyon cinereoargenteus), golden eagle
(Aquila chrysaetos), and free-roaming domestic dogs prey upon bighorn
sheep (Jones 1950; Cowan and Geist 1971). Predation generally has an
insignificant effect except on small populations such as the Sierra
Nevada bighorn sheep. Coyotes are the most abundant large predator
sympatric (occurring in the same area) with bighorn sheep populations
(Bleich 1999) and are known to have killed young Sierra Nevada bighorn
sheep (Vernon Bleich, California Department of Fish and Game, pers.
comm. 1999). In the late 1980s, mountain lion predation of Sierra
Nevada bighorn sheep increased throughout their range (Wehausen 1996).
This trend has continued into the 1990s, as evidenced by Table 1.
Predation by mountain lion probably was a natural occurrence and
part of the natural balance of this ecosystem. From 1907 to 1963, the
State provided a bounty on mountain lions; the State also hired
professional lion hunters for many years. The bounty most likely kept
the mountain lion population reduced such that bighorn sheep predation
was rare and insignificant. Between 1963 and 1968, mountain lions were
managed as a nongame and nonprotected mammal, and take was not
regulated. From 1969 to 1972, lions were re-classified as game animals.
A moratorium on mountain lion hunting began in 1972 and lion numbers
likely increased. In 1986, the species was again classified as a game
animal, but the California Department of Fish and Game (CDFG) hunting
recommendations were challenged in court in 1987 and 1988 (Torres et
al. 1996). In 1990, a State-wide ballot initiative (Proposition 117)
passed into law prohibiting the killing of mountain lions except if
humans or their pets or livestock are threatened. Another ballot
measure, Proposition 197, which would have modified current law
regarding mountain lion management failed to pass in 1996, largely
because of the public's concern that the change may allow mountain lion
hunting (Torres et al. 1996). With the removal of the ability to
control the mountain lion population, lion predation has become a
significant limiting factor for the Sierra Nevada bighorn sheep.
[[Page 19304]]
The increased presence of mountain lions appears to have changed
Sierra Nevada bighorn sheep winter habitat use patterns. Wehausen
(1996) looked at mountain lion predation in two bighorn sheep
subpopulations, one in the Granite Mountains of the eastern Mojave
Desert, and the other was the Mount Baxter subpopulation in the Sierra
Nevada. He found that the lions reduced the subpopulation in the
Granite Mountains to eight ewes between 1989 and 1991, and held it at
that level for 3 years, after which lion predation decreased and the
bighorn sheep subpopulation increased at 15 percent per year for 3
years. All the mortality in that subpopulation was attributed to
mountain lion predation. The Mount Baxter bighorn sheep subpopulation
abandoned its winter ranges, presumably due to mountain lion predation.
Forty-nine sheep were killed by lions on their winter range between
1976 and 1988 out of an average subpopulation size of 127 sheep. These
mortalities from mountain lion predation represented 80 percent of all
mortality on the winter range, and 71 percent for all ranges used.
There is also evidence that many of the bighorn sheep killed were
prime-aged animals (J. Wehausen, pers. comm. 1999).
The bighorn sheep on Mount Baxter moved to higher elevations
possibly to evade lions. By avoiding the lower terrain and higher
quality forage present during the spring, sheep emerge from the winter
months in poorer condition. Consequences from the change in habitat use
resulted in a decline in the Mount Baxter subpopulation due to
decreased lamb survival, because lambs were born later and died in
higher elevations during the winter. This may have also been the case
with the Lee Vining subpopulation decline, when the bighorn sheep ran
out of fat reserves at a time when they should have been replenishing
their reserves with highly nutritious forage from low elevation winter
ranges. Because of the winter habitat shift by the bighorn sheep, the
Mount Baxter subpopulation has declined significantly. With the large
decline of bighorn sheep on Mount Baxter, the total population of
Sierra Nevada bighorn sheep has now dropped below what existed when the
restoration program began in 1979 (Wehausen 1996; Advisory Group 1997).
In a 1996 survey on Mount Williamson, there was no evidence of groups
of sheep, and this subpopulation was the last one found using its low-
elevation winter range in 1986. Mountain lion predation may have led to
the extirpation of this subpopulation, one of the last two native
subpopulations of Sierra Nevada bighorn sheep (Wehausen 1996; J.
Wehausen, pers. comm. 1999).
The Sierra Nevada bighorn sheep restoration program used the Mount
Baxter subpopulation as the source of reintroduction stock from 1979 to
1988. The three reintroduced subpopulations at Lee Vining Canyon,
Wheeler Mountain, and Mount Langley all suffered from mountain lion
predation shortly after translocation of sheep (Wehausen 1996). The Lee
Vining Canyon subpopulation lost a number of sheep to mountain lion
predation, threatening the success of the reintroduction effort (Chow
1991, cited by Wehausen (1996)). The subpopulation was supplemented
with additional sheep and the State removed one mountain lion each year
for 3 years, which helped reverse the decline of this subpopulation
(Bleich et al. 1991 and Chow 1991, cited by Wehausen (1996)). Also,
because domestic sheep are preyed upon by mountain lions, livestock
operators who have a Federal permit to graze their sheep on USFS land
can get a depredation permit from the State, and have the U.S.
Department of Agriculture, Wildlife Services, remove the mountain lion.
The Lee Vining Canyon subpopulation occurs in the general area where
domestic sheep are permitted, and has benefitted for the last 4 or 5
years from the removal of two to three mountain lions per year that
were preying on domestic sheep (B. Pritchard, pers. comm. 1999).
D. The inadequacy of existing regulatory mechanisms. In response to
a very rapid decline in population numbers, in 1876, the State
legislature amended a 1872 law that provided seasonal protection for
elk, deer and pronghorn to include all bighorn sheep. Two years later,
this law was amended, establishing a 4-year moratorium on the taking of
any pronghorn, elk, mountain sheep or female deer. In 1882, this
moratorium was extended indefinitely for bighorn sheep (Wehausen et al.
1987; Wehausen et al. 1988). In 1971, California listed the California
bighorn sheep as ``rare.'' The designation was changed to
``threatened'' in 1984 to standardize the terminology of the amended
California Endangered Species Act (Advisory Group 1997), and upgraded
the species to ``endangered'' in 1999 (San Francisco Chronicle 1999).
Pursuant to the California Fish and Game Code and the California
Endangered Species Act, it is unlawful to import or export, take,
possess, purchase, or sell any species or part or product of any
species listed as endangered or threatened. Permits may be authorized
for certain scientific, educational, or management purposes. The
California Endangered Species Act requires that State agencies consult
with the CDFG to ensure that actions carried out are not likely to
jeopardize the continued existence of listed species.
The California Fish and Game Code provides for management and
maintenance of bighorn sheep. The policy of the State is to encourage
the preservation, restoration, and management of California's bighorn
sheep. The CDFG supports the concept of separating livestock from
bighorn sheep, by creating buffers, to decrease the potential for
disease transmission. Such separation would require the purchase and
elimination of livestock allotments. However, the State does not have
authority to regulate grazing practices on Federal lands. State listing
has not prompted the BLM or USFS to effectively address disease
transmission associated with Federal livestock grazing programs.
Since the Sierra Nevada bighorn sheep was listed by the State of
California in 1971, the CDFG has undertaken numerous efforts for the
conservation of the sheep, including but not limited to--(1) intensive
field studies; (2) reestablishment of three additional subpopulations
in historical habitat; (3) creation, in 1981, of the Sierra Nevada
Bighorn Sheep Interagency Advisory Group, including representatives
from Federal, State, and local resource management agencies which has
produced the Sierra Nevada Bighorn Sheep Recovery and Conservation Plan
(1984) and a Conservation Strategy for Sierra Nevada Bighorn Sheep
(1997); and (4) culling four mountain lions that were taking Sierra
Nevada bighorn sheep, which played a significant role in the efforts to
reestablish one subpopulation (Chow 1991, cited by Wehausen (1996)).
Mountain lion hunting has not occurred in California since 1972
(Torres et al. 1996). As a result of passage of Proposition 117 in 1990
prohibiting the hunting or control of mountain lions, the CDFG does not
have the authority to remove mountain lions to protect the Sierra
Nevada bighorn sheep and secure their survival.
Federal agencies have adequate authority to manage the land and
activities under their administration to benefit the welfare of the
bighorn sheep. Steps are being taken to enhance habitat through
prescribed burning to improve forage and maintain open habitat, and to
retire domestic sheep allotments that run adjacent to bighorn sheep
habitat. For example, 650 acres were burned in 1997 in Lee Vining
Canyon to reduce mountain lion hiding cover, and there
[[Page 19305]]
are plans to do more burns in other areas on USFS land (R. Perloff,
pers. comm. 1999). However, in some cases, because of conflicting
management concerns, conservation efforts are not proceeding as quickly
as necessary. Although efforts have been underway for many years, the
USFS has been unable to eliminate the known threat of contact between
domestic sheep and the Sierra Nevada bighorn sheep by either
eliminating adjacent grazing allotments, or modifying allotments such
that a sufficient buffer zone exists that would prevent contact between
wild and domestic sheep.
In 1971, the State, in cooperation with the USFS, established a
sanctuary for the Mount Baxter and Mount Williamson subpopulation of
Sierra Nevada bighorn sheep and called it the California Bighorn Sheep
Zoological Area (Zoological Area) (Wehausen 1979; Inyo National Forest
Land Management Plan (LMP) 1988). About 16,564 hectares (41,000 acres)
of USFS land was set aside for these two subpopulations. At the time,
it was felt that the reason for the species' decline was related to
human disturbance. The sanctuary was designed to regulate human use in
some areas, and reduce domestic sheep/wild sheep interaction by
constructing a fence below the winter range of the Mount Baxter
subpopulation along the USFS boundary (Wehausen 1979). Adjacent summer
range on NPS land was also given a restrictive designation to reduce
human disturbance (Wehausen 1979). The Zoological Area continues to
receive special management by the USFS; it encompasses land designated
as wilderness and mountain sheep habitat (LMP 1988; R. Perloff, pers.
comm. 1999).
E. Other natural or manmade factors affecting its continued
existence. The Sierra Nevada bighorn sheep population is critically
small with a total of only about 100 sheep known from five
subpopulations. There is no known interaction between the separate
subpopulations. The Sierra Nevada bighorn sheep currently is highly
vulnerable to extinction from threats associated with small population
size and random environmental events.
Although inbreeding depression has not been demonstrated in the
Sierra Nevada bighorn sheep, the number of sheep occupying all areas is
critically low. The minimum size at which an isolated group of this
species can be expected to maintain itself without the deleterious
effects of inbreeding is not known. Researchers have suggested that a
minimum effective population size of 50 is necessary to avoid short-
term inbreeding depression, and 500 to maintain genetic variability for
long-term adaptation (Franklin 1980). Small populations are extremely
susceptible to demographic and genetic problems (Caughley and Gunn
1996). Small populations suffer higher extinction probabilities from
chance events such as skewed sex ratio of offspring, (e.g., fewer
females being born than males). For example, the Mount Langley
subpopulation has been declining. In 1996-97, out of a subpopulation of
4 ewes and 10 rams, 5 lambs were born, of which 4 were female. Although
a positive event for this subpopulation, it could have been devastating
if the female:male ratio of offspring had been reversed (J. Wehausen,
pers. comm. 1999).
Small, isolated groups are also subject to extirpation by naturally
occurring random environmental events, e.g., prolonged or particularly
heavy winters and avalanches. In 1995, for example, a dozen sheep died
in a single avalanche at Wheeler Ridge (J. Wehauser, pers. comm. 1999).
Such threats are highly significant because currently the
subpopulations are small and it is also common in bighorn sheep for all
members of one sex to occur in a single group. During the very heavy
winters in the late 1970s and early 1980s, there was no notable
mortality in the subpopulations because they were using low elevation
winter ranges (J. Wehausen, pers. comm. 1999).
Competition for critical winter range resources can occur between
bighorn sheep and elk and/or deer (Cowan and Geist 1971). However,
competition between these species does not appear significant since
deer and bighorn sheep readily mix on winter range, and the habitat
overlap between elk and bighorn sheep is slight (Wehausen 1979).
In addition to disease, mountain lion predation, and random natural
events, other factors may contribute to bighorn sheep mortality. For
example, two subpopulations (Wheeler Ridge and Lee Vining) have ranges
adjacent to paved roadways exposing individuals from those
subpopulations to potential hazards. Bighorn sheep have been killed by
vehicles in Lee Vining Canyon on several occasions (V. Bleich, pers.
comm. 1999).
Reason for Emergency Determination
Under section 4(b)(7) of the Act and regulations at 50 CFR 424.20,
we may emergency list a species if the threats to the species
constitute an emergency posing a significant risk to its well-being.
Such an emergency listing expires 240 days following publication in the
Federal Register unless, during this 240-day period, we list the
species following the normal listing procedures. We discuss the reasons
why emergency listing the Sierra Nevada bighorn sheep as endangered is
necessary below. In accordance with the Act, if at any time after we
publish this emergency rule, we determine that substantial evidence
does not exist to warrant such a rule, we will withdraw it.
Historically, the Sierra Nevada bighorn sheep ranged throughout
central and southern Sierra Nevada. The historical habitat of the
Sierra Nevada bighorn sheep remains intact. However, the entire range
of the species has been reduced to five subpopulations--the Mount
Williamson and Mount Baxter subpopulations, which are composed of
native sheep, and the Lee Vining Canyon, Wheeler Ridge, and Mount
Langley subpopulations, which are descended from sheep taken from the
Mount Baxter subpopulation and translocated to historical habitat.
These subpopulations have decreased in numbers significantly in the
last several years (see Table 1). As discussed under factors C, D, and
E in the Summary of Factors Affecting the Species section above, the
immediacy of threats to the Sierra Nevada bighorn sheep is so great to
a significant proportion of the total population that the routine
regular listing process is not sufficient to prevent losses that may
result in extinction or loss of significant recovery potential. An
emergency posing a significant risk to the well-being and continued
survival of the Sierra Nevada bighorn sheep exists as the result of the
continual exposure to predation (primarily mountain lion), and the
effects of avoidance by bighorn sheep of areas in which they are
particularly vulnerable to predation by mountain lions. The Sierra
Nevada bighorn sheep is also threatened by the potential increase of
contact with domestic sheep in the spring and summer and the
transmission of disease. The factors creating an extreme situation are
discussed in detail below.
Because Sierra Nevada bighorn sheep exist only as a series of very
small subpopulations vulnerable to extinction, the survival of Sierra
Nevada bighorn sheep now depends on the most rapid possible increase in
as many subpopulations as possible. These small subpopulations are
vulnerable to extinction from chance demographic events and the
continual loss of genetic variation if they remain small.
[[Page 19306]]
Vulnerability to Demographic Problems
Five subpopulations remain that include a total of nine female
demes (i.e., local populations) (Mount Langley--eight ewes, Mount
Williamson--three ewes, Black Mountain--five ewes, Sand Mountain--five
ewes, Sawmill Canyon--two ewes, Wheeler Ridge--17 ewes, Mount Gibbs--
two ewes, Tioga Crest--one ewe, Mount Warren--five ewes) (J. Wehausen,
pers. comm. 1999). These demes are defined by separate geographic home
range patterns of the females. Of these, the Mount Williamson, Black
Mountain, and Tioga Crest demes appear not to use low elevation winter
ranges at all, and they will probably go extinct as a result (J.
Wehausen, pers. comm. 1999). The Black Mountain deme was previously
part of the Sand Mountain deme (part of the Mount Baxter subpopulation)
and became a separate deme after winter range abandonment occurred in
the late 1980s. The five remaining ewes in this deme appear not to know
of the Sand Mountain winter range, which lies considerably north of
their home range. They were almost certainly all born after winter
range abandonment on Sand Mountain. This deme has shown a steady
decline in size (J. Wehausen, pers comm. 1999).
There are six female demes that may persist, but all are still very
vulnerable to extinction due to small size. Of the two ewes and lamb
that spent February, 1998, at the mouth of Sawmill Canyon (another
Mount Baxter subpopulation deme), only a ewe and a lamb remained when
last seen there in 1998. Shortly after they were last seen, evidence of
a mountain lion was found on the rocks where they had been weathering a
month of severe winter storms. When the normal summer range of this
deme of females was investigated twice last summer, it was difficult to
find evidence of any sheep remaining. This deme may contain only a
single remaining ewe, or none (J. Wehausen, pers. comm. 1999).
The Sand Mountain deme has had only four ewes in it for almost this
entire decade. During the summer of 1998, Dr. John Wehausen finally
documented a yearling female with them, thus the total of five ewes
listed above. However, the four adult ewes must now be approaching the
ends of their lives, making this deme also very vulnerable to
extinction, even if they have been showing some increased winter range
use. Without successful births and recruitment of female lambs into
this deme quickly, this deme will experience a decline.
Currently, there is a large lion occupying the winter range areas
used by members of the Mount Langley deme. These ewes have been using
that winter range enough over the past three winters to be showing a
subpopulation increase (recruitment of five lambs for four ewes in the
past 2 years). This lion could easily reverse that trend by killing
multiple members of this deme and discouraging them from using this
winter range. These ewes can be expected to begin appearing on this
winter range any day (J. Wehausen pers. comm. 1999).
The Mount Warren deme that uses Lee Vining Canyon as a winter range
continues to decline. Besides the loss of numerous ewes last winter or
spring to unknown causes, one of two telemetered (radio-collared) ewes
was lost to a lion on the winter range in April, 1998. The collar of
the other ewe was recently dug out of a snow bank at 3050 m (10,000 ft)
in Deer Creek, but biologists will be unable to investigate her cause
of death until the summer of 1999 when the snow melts, allowing her
carcass to be found. She was last documented alive in late October
1998, but was not with a group of 13 sheep seen in mid-December, thus
she may have died in November. This leaves only five ewes in this deme.
If the lion that killed at least one ewe in April 1998 returns this
spring, it might seriously compromise the future of this deme (J.
Wehausen, pers. comm. 1999).
With the likely extinction of some of the existing demes, the
remaining demes become all the more important to the persistence of
this distinct population segment. We do not know which demes may
survive and which may die out. All population dynamics over the past 15
years have been unanticipated (J. Wehausen, pers. comm. 1999). In
short, it is not possible to predict population trajectories.
Individual mountain lions can do enormous damage to any of these small
demes, as can catastrophic events such as snow avalanches. The current
larger size of the Wheeler Ridge deme does not preclude it from
experiencing a sudden decline, as the Mount Warren deme experienced
last winter (J. Wehausen, pers. comm. 1999).
Every deme is critical to the survival of the DPS at this point. We
do not know which ewes in each deme may prove to be the ones critical
to persistence of those demes. Thus, every remaining female in every
deme is critically important to the persistence of their demes.
Lastly, the potential for contact with domestic sheep and the
transmission of disease could, by itself, eliminate an entire deme.
Domestic sheep continue to stray into Sierra Nevada bighorn sheep
habitat. Recently, domestic sheep have come in close proximity to the
resident bighorn sheep on numerous occasions, but, by good fortune,
domestic sheep have not come into contact with bighorn sheep during
these events.
Vulnerability to demographic problems must be viewed as a
combination of immediate threats of predation, changed habitat use due
to the presence of mountain lions, the resultant decline in ewe
nutrition and lamb survivorship, exposure to environmental
catastrophes, and the transmission of disease from domestic sheep.
Vulnerability to Genetic Problems
Also unknown is the current distribution of genetic variation among
all of these subpopulations. It will be at least a year before fecal
DNA research will shed some light on this question (J. Wehausen, pers
comm. 1999). It is likely that each subpopulation has lost some genetic
variability thereby reducing its ability for long-term adaptation. The
ultimate goal of conserving this DPS must be to preserve as much of its
genetic variation as possible. It is likely that all or some of the
existing demes now contain some variation not represented in others.
Once some measure of this distribution is known through DNA analysis, a
possible goal will be to attempt to distribute that variation among as
many subpopulations as possible. Until some measure of the distribution
of genetic variation exists, every deme should be considered a
significant portion of the overall population, just as they should from
a demographic perspective. Maintenance of genetic variability requires
preservation of rams in addition to ewes.
In summary, it is now necessary to consider that every individual
is currently a significant portion of the overall population of Sierra
Nevada bighorn sheep because of the small number of sheep remaining and
extreme vulnerability of every deme to extinction. Losses from
predation and the potential for disease transmission through contact
with domestic sheep are threats posing a significant risk to the well-
being of the DPS. For these
[[Page 19307]]
reasons, we find that the Sierra Nevada bighorn sheep is in imminent
danger of extinction throughout all or a significant portion of its
range and warrants immediate protection under the Act.
Critical Habitat
Critical habitat is defined in section 3 of the Act as--(i) the
specific area within the geographical area occupied by a species, at
the time it is listed in accordance with the Act, on which are found
those biological features (I) essential to the conservation of the
species and (II) that may require special management considerations or
protection; and (ii) specific areas outside the geographical area
occupied by a species at the time it is listed, upon a determination
that such areas are essential for the conservation of the species.
``Conservation'' means the use of all methods and procedures needed to
bring the species to the point at which listing under the Act is no
longer necessary.
Section 4(a)(3) of the Act, and implementing regulations (50 CFR
424.12) require that, to the maximum extent prudent and determinable,
the Secretary designate critical habitat at the time the species is
determined to be endangered or threatened. Our regulations (50 CFR
424.12(a)) state that critical habitat is not determinable if
information sufficient to perform required analysis of impacts of the
designation is lacking or if the biological needs of the species are
not sufficiently well known to permit identification of an area as
critical habitat. Section 4(b)(2) of the Act requires us to consider
economic and other relevant impacts of designating a particular area as
critical habitat on the basis of the best scientific data available.
The Secretary may exclude any area from critical habitat if he
determines that the benefits of such exclusion outweigh the
conservation benefits, unless to do such would result in the extinction
of the species.
We find that designation of critical habitat for the Sierra Nevada
bighorn sheep is not determinable at this time. We have determined that
information sufficient to perform required analysis of impacts of the
designation is lacking. We specifically solicit this information in the
proposed rule (see ``Public Comments Solicited'' section) published in
this same issue of the Federal Register. When a ``not determinable''
finding is made, we must, within 2 years of the publication date of the
original proposed rule, designate critical habitat, unless the
designation is found to be not prudent. We will protect Sierra Nevada
bighorn sheep habitat through section 7 consultations to determine
whether Federal actions are likely to jeopardize the continued
existence of the species, through the recovery process, through
enforcement of take prohibitions under section 9 of the Act, and
through the section 10 process for activities on non-Federal lands with
no Federal nexus.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Act include recognition, recovery actions,
requirements for Federal protection, and prohibitions against certain
activities. Recognition through listing encourages and results in
conservation actions by Federal, State, and private agencies, groups
and individuals. The Act provides for possible land acquisition and
cooperation with the States and requires that recovery actions be
carried out for all listed species. We discuss the protection required
of Federal agencies and the prohibitions against taking and harm, in
part, below.
Section 7(a) of the Act, as amended, requires Federal agencies to
evaluate their actions with respect to any species that is proposed or
listed as endangered or threatened, and with respect to its critical
habitat, if any is being designated. Regulations implementing this
interagency cooperation provision of the Act are codified at 50 CFR
Part 402. Section 7(a)(4) of the Act requires Federal agencies to
confer informally with us on any action that is likely to jeopardize
the continued existence of a proposed species or result in destruction
or adverse modification of proposed critical habitat. If a species is
subsequently listed, section 7(a)(2) requires Federal agencies to
ensure that activities they authorize, fund, or carry out are not
likely to jeopardize the continued existence of such a species or to
destroy or adversely modify its critical habitat. If a Federal agency
action may affect a listed species or its critical habitat, the
responsible Federal agency must enter into consultation with us.
Federal agency actions that may require conference and/or consultation
include those within the jurisdiction of the USFS, BLM, and NPS.
We believe that protection of the Sierra Nevada bighorn sheep
requires reduction of the threat of mountain lion predation,
particularly during the months of April and May 1999 when bighorn sheep
attempt to use low elevation winter ranges to obtain necessary
nutrition after lambing, and ewes and lambs are most vulnerable to lion
predation. Emergency listing will allow the Service to remove mountain
lions that threaten Sierra Nevada bighorn sheep. Removal of mountain
lions may not necessarily involve lethal techniques.
We believe that protection of the Sierra Nevada bighorn sheep also
requires reduction of the threat of disease transmission from domestic
sheep by preventing domestic sheep from coming into contact with
bighorn sheep. We will work with the USFS to reduce the threat of
disease transmission by domestic sheep. Reduction of this threat may
involve elimination of grazing allotments adjacent to bighorn sheep
habitat, or modifying allotments to create a sufficient buffer zone
that would prevent contact between domestic sheep and bighorn sheep.
The Act and implementing regulations found at 50 CFR 17.21 set
forth a series of general prohibitions and exceptions that apply to all
endangered wildlife. The prohibitions, as codified at 50 CFR 17.21, in
part, make it illegal for any person subject to the jurisdiction of the
United States to take (including harass, harm, pursue, hunt, shoot,
wound, kill, trap, capture, collect, or attempt any such conduct),
import or export, transport in interstate or foreign commerce in the
course of commercial activity, or sell or offer for sale in interstate
or foreign commerce any listed species. It is also illegal to possess,
sell, deliver, carry, transport, or ship any such wildlife that has
been taken illegally. Certain exceptions apply to our agents and State
conservation agencies.
Permits may be issued to carry out otherwise prohibited activities
involving endangered wildlife species under certain circumstances.
Regulations governing permits are at 50 CFR 17.22 and 17.23. For
endangered species, such permits are available for scientific purposes,
to enhance the propagation or survival of the species, or for
incidental take in connection with otherwise lawful activities.
[[Page 19308]]
It is our policy, published in the Federal Register on July 1, 1994
(59 FR 34272), to identify to the maximum extent practical at the time
a species is listed those activities that would or would not constitute
a violation of section 9 of the Act. The intent of this policy is to
increase public awareness of the effect of a listing on proposed and
ongoing activities within a species' range. Activities that we believe
could potentially result in take include, but are not limited to:
(1) Unauthorized trapping, capturing, handling or collecting of
Sierra Nevada bighorn sheep. Research activities involving trapping or
capturing Sierra Nevada bighorn sheep will require a permit under
section 10(a)(1)(A) of the Act.
(2) Unauthorized livestock grazing that results in transmission of
disease or habitat destruction by the accidental or intentional escape
of livestock.
Activities that we believe are unlikely to result in a violation of
section 9 are:
(1) Possession, delivery, or movement, including interstate
transport and import into or export from the United States, involving
no commercial activity, of dead specimens of Sierra Nevada bighorn
sheep that were collected prior to the date of publication of this
emergency listing rule in the Federal Register;
(2) Unintentional vehicle collisions resulting in death or injury
to Sierra Nevada bighorn sheep, when complying with applicable laws and
regulations; and
(3) Normal, authorized recreational activities in designated
campsites or recreational use areas and on authorized trails.
Questions regarding any specific activities should be directed to
our Ventura Fish and Wildlife Office (see ADDRESSES section). Requests
for copies of the regulations regarding listed wildlife and about
prohibitions and permits may be addressed to the U.S. Fish and Wildlife
Service, Ecological Services, Endangered Species Permits, 911 Northeast
11th Avenue, Portland, Oregon 97232-4181 (telephone 503/231-2063;
facsimile 503/231-6243).
National Environmental Policy Act
We have determined that Environmental Assessments and Environmental
Impact Statements, as defined in the National Environmental Policy Act
of 1969, need not be prepared in connection with regulations adopted
pursuant to section 4(a) of the Endangered Species Act of 1973, as
amended. We published a notice outlining our reasons for this
determination in the Federal Register on October 25, 1983 (48 FR
49244).
Paperwork Reduction Act
This rule does not contain any new collections of information other
than those already approved under the Paperwork Reduction Act, 44
U.S.C. 3501 et seq., and assigned Office of Management and Budget
clearance number 1018-0094. 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 control number. For additional
information concerning permit and associated requirements for
endangered species, see 50 CFR 17.21 and 17.22.
References Cited
A complete list of references cited in this rule is available upon
request from the Ventura Fish and Wildlife Office of the U.S. Fish and
Wildlife Service (see ADDRESSES section).
Author
The primary author of this emergency rule is Carl Benz of the
Ventura Fish and Wildlife Office of the U.S. Fish and Wildlife Service
(see ADDRESSES section).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Regulation Promulgation
Accordingly, part 17, subchapter B of chapter I, title 50 of the
Code of Federal Regulations, is amended 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.
2. In Sec. 17.11(h) add the following to the List of Endangered and
Threatened Wildlife in alphabetical order under MAMMALS:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
SPECIES Vertebrate
-------------------------------------------------------- population where Critical Special
Historic range endangered or Status When listed habitat rules
Common name Scientific name threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
MAMMALS
* * * * * * *
Sheep, Sierra Nevada bighorn..... Obis canadensis U.S.A. (western U.S.A. (CA-Sierra E 660 NA NA
californiana. conterminous Nevada).
states), Canada
(southwest),
Mexico (north).
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 19309]]
Dated: April 14, 1999.
Jamie Rappaport Clark,
Director, Fish and Wildlife Service.
[FR Doc. 99-9935 Filed 4-19-99; 8:45 am]
BILLING CODE 4310-55-P
