[Federal Register Volume 59, Number 188 (Thursday, September 29, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-24065]
[[Page Unknown]]
[Federal Register: September 29, 1994]
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Part III
Department of the Interior
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Fish and Wildlife Service
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50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Determination of
Endangered Status for the Pacific Pocket Mouse; Final Rule
DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
RIN 1018-AC39
Endangered and Threatened Wildlife and Plants; Determination of
Endangered Status for the Pacific Pocket Mouse
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: The Fish and Wildlife Service (Service) determines the Pacific
pocket mouse (Perognathus longimembris pacificus) to be an endangered
species throughout its range in coastal southern California, pursuant
to the Endangered Species Act of 1973, as amended (Act). Critical
habitat is not being designated. This small rodent is an obligate
resident of river and marine alluvium and coastal sage scrub plant
communities in the immediate vicinity of the coast. Although the
Pacific pocket mouse formerly occurred at a minimum of 8 general
locales encompassing some 29 sites from Los Angeles County south to San
Diego County, the only known, confirmed population extant occurs on the
Dana Point Headlands in Orange County, California. A maximum of 36
confirmed, individual Pacific pocket mice has been detected on 3.75
acres of identified occupied habitat during the last 20 years. The
Pacific pocket mouse is threatened with extinction due to documented
depredation by domestic cats and habitat loss and fragmentation as a
result of past and continuing land development projects. This rule
implements and guarantees continued Federal protection provided by the
Act for the Pacific pocket mouse, which was emergency listed as
endangered on January 31, 1994 for a period of 240 days.
EFFECTIVE DATE: September 26, 1994.
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, Carlsbad Field Office, 2730 Loker Avenue West,
Carlsbad, California 92008.
FOR FURTHER INFORMATION CONTACT: Mr. Gail C. Kobetich, Field
Supervisor, at the address listed above (telephone 619/431-9440).
SUPPLEMENTARY INFORMATION:
Background
The Pacific pocket mouse (Perognathus longimembris pacificus) is
one of 19 recognized subspecies of the little pocket mouse (Perognathus
longimembris) (Hall 1981). This species is one of the smallest members
of the family Heteromyidae, which consists of spiny pocket mice
(Heteromys and Liomys), pocket mice (Perognathus and Chaetodipus),
kangaroo rats (Dipodomys), and kangaroo mice (Microdipodops). Virtually
all (if not all) members of this family are nocturnal, granivorous and
have external, deep, fur-lined cheek pouches (Ingles 1965; Dr. P.
Brylski, consulting mammalogist, pers. comm., 1993).
Perognathus longimembris ranges in size from about 110 to 151
millimeters (mm) (4.3 to 5.9 inches) from nose to tip of tail (Hall
1981) and weighs 7 to 9 grams (\1/4\ to \1/3\ oz.) (Burt and
Grossenheider 1976). The body pelage is spineless, bristle-free, and
predominately brown, pinkish buff or ochraceous buff above and light
brown, pale tawny, buff, or whitish below. There are typically two
small patches of lighter hairs at the base of the ear. The tail can be
either distinctly or indistinctly bicolored. The little pocket mouse
exhibits a high degree of geographic variation in pelage color (Hall
1981; see also Ingles 1965). Vocalizations of this species include a
high-pitched squeal.
The Pacific pocket mouse is the smallest subspecies of the little
pocket mouse, ranging up to 131 mm (5.2 inches) in length from nose to
tip of the long tail. The tail, hind foot, and skull structures of
Pacific pocket mice are also the smallest of all little pocket mouse
subspecies (Huey 1939). Stephens (1906) labeled the species an ``* * *
exceedingly small [p]ocket [m]ouse * * *'' The Pacific pocket mouse is
one of the smallest rodents in the world.
The Los Angeles pocket mouse (Perognathus longimembris brevinasus),
which occurs mostly northeast of, and well inland from, the Pacific
pocket mouse, is the only other subspecies of little pocket mouse that
occurs in southern California west of the deserts. Individual Los
Angeles pocket mice range in size from 125 to 145 mm (4.9 to 5.7
inches) long. Overall, Los Angeles pocket mice have longer tails, hind
feet, skulls, and nasal bones than Pacific pocket mice (Huey 1939).
The Pacific pocket mouse was originally described by Mearns (1898)
as a distinct species, Perognathus pacificus, based on the type
specimen that was collected on the shore of the Pacific Ocean at
Mexican Boundary Monument 258 in San Diego County, California. Although
von Bloeker (1931a,b) initially recognized the Pacific pocket mouse as
a distinct species, he subsequently concluded that P. pacificus
represented two subspecies of the little pocket mouse, P. longimembris
pacificus and P. l. cantwelli, after examining additional specimens
(von Bloeker 1932). Subsequent to a biometric analysis of 331 specimens
of the little pocket mouse, Huey (1939) recognized P. l. pacificus to
be inclusive of the two subspecies described by von Bloeker (1932).
Subsequent taxonomic treatments (e.g., Hall 1981; Williams et al. 1993)
have retained the Pacific pocket mouse as a distinct subspecies.
Although a taxonomic review of P. longimembris may be appropriate, the
Pacific pocket mouse has been described as distinct from related forms
(Dr. D. Williams, mammalogist, in litt, 1993).
Under section 3(15) of the Act (16 U.S.C. 1531 et seq.), the term
``species'' is defined to include recognized subspecies. Therefore,
throughout the remainder of this rule, Perognathus longimembris
pacificus (hereafter referred to as the Pacific pocket mouse), is
treated as a ``species''.
The Pacific pocket mouse is endemic to the immediate coast of
southern California from Marina del Rey and El Segundo in Los Angeles
County, south to the vicinity of the Mexican border in San Diego County
(Hall 1981, Williams 1986, Erickson 1993). The species has not been
recorded outside of California (Williams et al. 1993; Erickson 1993).
Erickson (1993) noted further that the Pacific pocket mouse has not
been reliably recorded more than approximately 2 miles (3 kilometers)
inland from the coast or above 600 feet (180 meters) in elevation.
The habitat requirements of the Pacific pocket mouse are not well
understood, but they are known to occur on fine-grain, sandy substrates
in the immediate vicinity of the Pacific Ocean (Mearns 1898, von
Bloeker 1931; Grinnell 1933; Bailey 1939). The Pacific pocket mouse is
or was known to inhabit coastal strand, coastal dunes, river alluvium,
and coastal sage scrub growing on marine terraces (Grinnell 1933;
Meserve 1972; Erickson 1993). Stephens (1906) trapped a female ``* * *
on a dry mesa a short distance back from the seashore.'' von Bloeker
(1931a) reported that Pacific pocket mice detected near San Diego were
found only in open patches of ground that were otherwise surrounded by
weedy growth. M'Closkey (1972) and Meserve (1972, 1976b) detected the
Pacific pocket mouse on sandy substrates in coastal sage scrub habitats
in the San Joaquin Hills in Orange County, California. Brylski (1993)
detected the only known, confirmed population extant on the Dana Point
Headlands on loose sand substrates in a coastal sage scrub community
dominated by California buckwheat (Eriogonum fasiculatum) and
California sage (Artemisia californica). Brylski (1993) commented that
the Pacific pocket mouse's preferred habitat ``* * * appears to be open
coastal sage scrub on fine, sandy soil.''
Little quantitative information is available on the ecology and
life history of the Pacific pocket mouse. However, the attributes of
the little pocket mouse and the available data that pertain to the
Pacific pocket mouse subspecies suggest that this small rodent is
facultatively or partially fossorial, relatively sedentary, primarily
granivorous, and able to become torpid, estivate, or hibernate in
response to adverse environmental conditions (e.g., Ingles 1965; Kenagy
1973; Dr. P. Meserve, academic mammalogist, pers. comm., 1994; Dr. R.
MacMillan, academic mammalogist, pers. comm., 1994).
During those periods that they are not active on the surface of
preferred substrates or in preferred habitats, Pacific pocket mice
apparently dwell in underground burrows. Erickson (1993) noted that
``[n]umerous small burrows revealed the presence of some colonies to
early collectors.'' Kenagy (1973) observed that little pocket mice may
stay in their burrows continuously for up to five months in winter,
alternating between periods of dormancy and feeding on stored seeds.
Periods of dormancy apparently may be induced by, or correlated with,
food shortage (Kenagy 1973). Ingles (1965) noted that ``[t]he ability
of the little pocket mouse to become dormant for only a few bad nights
is an important factor in its survival.''
While active and above ground, little pocket mice have ranged up to
1,000 feet (320 meters) from their burrows in a 24-hour period (Burt
and Grossenheider 1976). However, based on his study from 1969-1973 in
the Owens Valley, California, Kenagy (1973) concluded that ``* * * the
maximum distance moved during the night by this little mouse was
undoubtedly much less than 50 m.'' Reported little pocket mouse home
ranges ranged in size from 0.12 to 0.56 hectares (0.30 to 1.4 acres)
and populations ranged in density from 1 to 5.5 individuals/hectare
(0.4 to 2.2 individuals/acre) in Joshua Tree National Monument,
California (Chew and Butterworth 1964). Adult density at Dana Point
Headlands was estimated to be 5.9/hectare (2.4/acre) by Brylski (1993).
Pacific pocket mice primarily eat the seeds of grasses and forbs
(von Bloeker 1931; Meserve 1972, 1976a). Meserve (1976a) observed
further that other plant materials were consumed, albeit in
comparatively smaller quantities. P. Brylski (pers. comm., 1993)
observed that ``Pacific pocket mice foraged mainly on the seeds of
grasses and, to a lesser degree, on leafy vegetation.'' Jameson and
Peeters (1988) reported that little pocket mice, like other pocket mice
species, also eat soil-dwelling insects.
Relatively little is known of the breeding biology of Pacific
pocket mice. Erickson (1993), relying largely on data provided by
Meserve (1972), noted that ``[p]regnant and lactating females have been
found from April through June with immatures noted from June through
September.'' P. Brylski (pers. comm., 1993) observed lactating females
in July and noted that two litters were produced that year. Limited
reproduction was attributed to juveniles in the Dana Point Headlands
population (P. Brylski, pers. comm., 1993). Jameson and Peeters (1988)
described the little pocket mouse as ``rather prolific'' and indicated
that ``[p]regnancies occur in spring and fall with a summer lull.''
Historical records indicate that the Pacific pocket mouse occurred
in 8 general areas encompassing some 29 separate trapping sites.
Approximately 80 percent of all Pacific pocket mouse records are from
1931 or 1932 (Erickson 1993). The following summary of records is
organized by county:
Los Angeles County. The Pacific pocket mouse historically was
detected in three areas--Marina del Rey/El Segundo, Wilmington, and
Clifton. One hundred and eighteen specimens or live captures were
recorded for the Marina Del Rey/El Segundo area from 1918 to 1938, with
most (86) of these records coming from ``Hyperion''; see Erickson
(1993). Three specimens were collected in Wilmington in 1865 (voucher
specimens on deposit at the Museum of Vertebrate Zoology, University of
California, Berkeley) and four were collected in ``Cliffton'' [sic] in
1931. Four specimens from San Fernando in 1932 that were originally
labeled as P. pacificus/P. cantwelli were referred to as P. l.
brevinasus by von Bloeker (1932); see Erickson (1993). There have been
no records of Pacific pocket mice from Los Angeles County since 1938
(Erickson 1993; P. Brylski, in litt, 1993).
Orange County. The Pacific pocket mouse has been confirmed at two
locales in Orange County: the San Joaquin Hills and Dana Point. The
species was found in Buck Gully (P. Meserve, pers. comm., 1994) and
nearby ``Spyglass Hill'' in the San Joaquin Hills from 1968 to 1971
(M'Closkey 1972; Meserve 1972; R. MacMillan, pers. comm., 1994). Forty-
four specimens or live captures from ``Spyglass Hill'' were recorded
from 1968-1971 (see Erickson 1993). The only known, confirmed
population extant of the Pacific pocket mouse was rediscovered in July
of 1993 on the Dana Point Headlands in Orange County, California
(Brylski 1993). G. Cantwell had previously collected 10 specimens of
this species at this locale in May of 1932 (voucher specimens on
deposit at the Natural History Museum of Los Angeles County).
Possible, recent records from Crystal Cove State Park (approx. 16
km (10 mi) NW Dana Point) resulting from pitfall trapping (see R.
MacMillan, pers. comm., 1994) await confirmation given the uncertainty
expressed by the observer and the negative results of recent walk-over
and trapping surveys there (see P. Brylski, in litt, 1994 and J. Webb,
in litt, 1994).
San Diego County. The Pacific pocket mouse historically was
confirmed at three general locales in San Diego County--the San Onofre
Area, Santa Margarita River Estuary, and the lower Tijuana River
Valley. One specimen was obtained at San Onofre in 1903 and two others
were secured at that locale in 1931. Seventy-one specimens or live
captures were recorded for the Santa Margarita River mouth area between
1931 and 1936, with the majority (50) of these reported for
``Oceanside''. One hundred and thirty-four specimens or live captures
have been recorded from the lower Tijuana River Valley, including the
type specimen. There has not been a confirmed Pacific pocket mouse
record at these locales or elsewhere in San Diego County since 1932
(see Erickson 1993).
However, there have been three recent, unconfirmed reports of the
Pacific pocket mouse from San Diego County. A document released by the
California Department of Fish and Game (Mudie et al. 1986) pertaining
to the wildlife resources at the San Dieguito Lagoon, Del Mar, and at
least one subsequent environmental ``baseline study'' pertaining to
that locale (see S. Montgomery, consulting biologist, in litt, 1994 and
R. Erickson, consulting biologist, pers. comm., 1994) provide species
lists that contain the little pocket mouse (Perognathus longimembris).
Given the location of the survey effort, it seems almost certain that
any and all little pocket mice recorded at this locale would be Pacific
pocket mice. However, it was subsequently ascertained that none of the
surveyors or report authors could recall capturing a little pocket
mouse on the site or reporting same (e.g., Montgomery in litt, 1994; R.
Erickson, consulting biologist, pers. comm., 1994). Subsequent walk-
over surveys of the area in 1992 did not reveal the presence of the
Pacific pocket mouse (Dr. P. Behrends, consulting mammalogist, pers.
comm., 1994).
A single Pacific pocket mouse was reported from Lux Canyon,
Encinitas, in June 1989. The record is now considered only probable by
the observer (Erickson 1993).
Most recently and since the publishing of the proposed and
emergency rules, Mr. S. Tremor (in litt, 1994) reported what he
believes to be a single Pacific pocket mouse from a locale in Del Mar,
California. However, the animal escaped before photographs or a pelage
description could be obtained. Given these considerations, the Service
concludes, in the present absence of definitive or additional
information, that the Del Mar observation, although certainly deserving
of further attention and investigation, remains unconfirmed until such
time that a positive species identification can be made. P. Brylski
(pers. comm., 1994) independently has arrived at the same conclusion.
Accordingly, the only known, recently confirmed population of the
Pacific pocket mouse extant remains on the Dana Point Headlands.
Between 25 to 36 individual Pacific pocket mice were detected there by
Brylski (1993) during trapping surveys that extended into August. Prior
to this recent rediscovery of the Pacific pocket mouse at the Dana
Point Headlands, the Pacific pocket mouse had not been positively
observed since 1971 (see Erickson 1993). Numerous, relatively recent
small-mammal survey and trapping efforts within the potential range of
the Pacific pocket mouse (e.g., Salata 1981; Jones and Stokes 1990;
Taylor and Tiszler 1991; D. Erickson, pers. comm. 1993; P. Brylski, in
litt, 1993; P. Behrends, pers. comm., 1994; Dr. P. Kelly, mammalogist,
pers. comm., 1994; R. MacMillan, pers. comm., 1994; Dr. R. Dingman,
mammalogist, pers. comm., 1994; Dr. J. Webb, biologist, in litt, 1994;
S. Montgomery, consulting biologist, in litt, 1994; P. Brylski, in
litt, 1994; United States Fish and Wildlife Service 1994a; United
States Fish and Wildlife Service 1994b) have failed to locate
additional extant populations.
From a species perspective, the persistence of the Pacific pocket
mouse is important, perhaps essential, in preserving an important and
unique portion of the historic habitat of the little pocket mouse and
in preserving potentially unique genetic stock. The Pacific pocket
mouse's adaptation to, and dependence on, coastal dune and coastal
alluvium substrates and coastal sage scrub habitats have probably
contributed to a genetic divergence from other subspecies of the little
pocket mouse. Maintaining a broad genetic stock may be critically
important to the species ability to adapt to changing environmental
conditions. The apparent sedentary nature of the Pacific pocket mouse
(Meserve 1972; Meserve, pers. comm., 1994) and the fragmentation of
this species' potential habitat increase the probability that localized
extirpations caused by the destruction of habitat or movement corridors
will be permanent. This could significantly reduce the extent of any
possible introgression between subpopulations and reduce genetic
heterozygosity and the overall fitness of the species. Such
perturbations could result in a permanent loss of genetic stock or, at
the extreme, result in the extinction of the Pacific pocket mouse.
Previous Federal Action
The Pacific pocket mouse was designated by the Service as a
category 2 candidate species for Federal listing as an endangered or
threatened species in 1985 (50 FR 37966). It was retained in this
category in subsequent notices of review published by the Service in
the Federal Register in 1989 and 1991 (54 FR 554 and 56 FR 58804,
respectively). Category 2 comprises taxa for which information now in
the possession of the Service indicates that proposing to list as
endangered or threatened is possibly appropriate, but for which
conclusive data on biological vulnerability and threat are not
currently available to support proposed rules.
Largely because of documented, imminent threats to the only known
population of the Pacific pocket mouse, the Service published an
emergency rule to list the species as endangered on February 3, 1994
(59 FR 5306). Interim protection afforded the Pacific pocket mouse as
the result of the promulgation of the emergency rule expires on
September 28, 1994. A proposed rule to list the Pacific pocket mouse
was concurrently published with the emergency rule (59 FR 5311).
Summary of Comments and Recommendations
In the proposed rule and associated news release announcing the
promulgation of the proposed rule and emergency rule, all interested
parties were requested to submit factual reports or information that
might contribute to the development of a final rule. The news release
was provided to media throughout southern California and to the
national media. In addition, 3 Federal agencies, 3 state agencies, 15
county and city governments, and 6 other potentially affected or
interested parties were individually notified of the promulgation of
the emergency and proposed rules. Representatives of Marine Corps Base,
Camp Pendleton; the County of Orange; the City of Dana Point; and the
Dana Point Headlands landowner, among others, were personally contacted
by Service personnel. Newspaper articles in the Los Angeles Times and
Orange County Register announcing the emergency listing of the Pacific
pocket mouse and scheduled public hearing appeared in February and
March 1994.
The Service held a public hearing on the proposed rule on March 24,
1994, in San Clemente, Orange County, California. Notification of the
hearing was published in the Federal Register on March 1, 1994 (59 FR
9720). Newspaper notices specifically announcing the hearing and
inviting general public comment on the proposal additionally were
published in the Orange County Register and San Diego Union Tribune.
Approximately 25 people attended the hearing and seven of these
provided oral comments.
A total of 71 comments was received. Although the comment period
technically closed on April 4, 1994, the Service considered all
comments received through June 20, 1994. (Five comments were received
by the Carlsbad Field Office after the deadline, including one from an
interested and potentially affected municipal jurisdiction.) Multiple
comments whether written or oral from the same party are regarded as
one comment.
Of the comments received, 48 persons or organizations (68 percent)
supported listing; 10 (14 percent) urged the protection of the only
confirmed, occupied habitat of the Pacific pocket mouse on the Dana
Point Headlands; 3 (4 percent) were against the listing; 3 (4 percent)
were in favor of the development of the Dana Point Headlands; 4 (6
percent) urged the application of sound science to the listing process;
and 3 (4 percent) were noncommittal.
Two Federal agencies and the sole city government responding were
neutral on the issue of listing. The California Department of Fish and
Game previously had gone on record as supporting a proposal to list the
Pacific pocket mouse (K. Berg, in litt, 1992). No citizens groups or
organizations opposed the proposed listing. Attorneys for one landowner
voiced opposition to both the emergency listing and proposed listing.
The Service has reviewed all of the written and oral comments
described above including those that were received outside of the
formal comment periods. Based on this review, 11 relevant issues have
been identified and are discussed below. The Service considers these
issues to be representative of the comments questioning or opposing the
proposed listing action.
Issue 1: One commenter noted that the listing action should not
occur because the Pacific pocket mouse subspecies is not a valid taxon
and the subject of taxonomic controversy. The commenter quotes a letter
from Mr. P. Collins, Associate Curator of the Santa Barbara Museum of
Natural History, to D. Erickson, in which it is stated that ``* * * I
think that it is imperative that the taxonomic status of the various
subspecies of Perognathus longimembris in central and southern
California be reevaluated using modern systematic techniques such as
electrophoresis and multivariate morphometrics. The systematic
questions will need to be answered before any population of this
species can be proposed for possible listing status.'' The commenter
further noted that ``* * * Service officials appeared to have
significant concerns regarding the appropriateness of listing the PPM
[Pacific pocket mouse] in the absence of sufficient data on the
taxonomy issue--even as recently as November 1993. (Exhibit J)'' The
Service is obliged to consider available data pertaining to the genetic
relationship between the Pacific pocket mouse and other groups of
little pocket mice as provided by Patton et al. (1981). The commenter
added that the subspecies designation is controversial and that ``* * *
alleged morphological characteristics could be the product of seasonal
or ecological variation among pocket mice. A proper resolution of the
resolution of the PPM's true status is required before the Service can
act to list the PPM as a subspecies. * * *''
Service Response: Although the Service initially and independently
reviewed all available information relating to the taxonomy, ecology,
biology, status and distribution of the Pacific pocket mouse, the
Service also solicited comments or suggestions from the public, other
concerned governmental agencies, the scientific community, industry,
and any other interested party on these and all other aspects of the
proposed rule. In particular, the Service has made a concerted effort
to obtain the best available scientific information regarding the
taxonomy of the Pacific pocket mouse.
Despite a recent taxonomic treatment of the rodent family
Heteromyidae published by the American Society of Mammalogists
(Society), the Service nonetheless solicited the expert opinions and
input of, among others, the President of the Society and the principal
author of the published taxonomy (Williams et al. 1993) regarding the
taxonomic validity of Perognathus longimembris pacificus. The Service
considers the Society to be a recognized authority on the taxonomy and
biology of North American mammals.
As is suggested by the commenter, the Service does have significant
concerns regarding the appropriateness of listing any species and
carefully considers its mandate in that regard as set forth by section
4 of the Act. In the present case, however, the Service cannot agree
that there is, as suggested by the commenter, an absence of sufficient
data pertaining to the taxonomy of the Pacific pocket mouse.
The Pacific pocket mouse was originally described by Mearns (1898)
as a distinct species, Perognathus pacificus. Subsequent to several
intervening taxonomic treatments or investigations (e.g., Stephens
1906; von Bloeker 1932; Grinnell 1933; Huey 1939), Hall (1981) and
others have recognized the Pacific pocket mouse as a distinct
subspecies of the little pocket mouse. Although the taxonomical history
of this species spans some 90 years and there is a current, peer-
reviewed, published classification of the heteromyid rodents inclusive
of the pocket mice taxa (Williams et al. 1993), the Service
nevertheless contacted Dr. Williams to insure that there was no doubt
as to the current, correct taxonomic treatment of the subject
subspecies (see D. Williams, in litt, 1993, which is identical to the
commenter's Exhibit J). Dr. Williams (in litt, 1993) confirmed the
taxonomic validity and distinctness of the Pacific pocket mouse.
Although it is recognized that a ``* * * modern revision of the
longimembris complex might cause a re-evaluation of the various
subspecies of this taxon'', the Service presently has no information or
scientific basis to refute a recognized authority's assertion that ``*
* * there is certainly every reason to consider pacificus valid with
current information'' (Dr. J. L. Patton, President of the American
Society of Mammalogists, in litt, 1994). Patton et al. (1981) did not
address the biochemical systematics of perognathine pocket mice (which
include the little pocket mouse and Pacific pocket mouse).
Mr. Collins has informed the Service (pers. comm., 1994) that he
has no alternative taxonomy to propose and is not now, and will not be
in the foreseeable future, investigating the taxonomy of Perognathus
longimembris. By contrast, P. Brylski has indicated (in litt, 1993)
that he and others are currently investigating the systematics of
Perognathus longimembris utilizing sequencing regions of mitochondrial
DNA and morphology. To date, no results from these studies have been
published or are otherwise forthcoming. In the interim, P. Brylski (in
litt, 1994) has most recently indicated that ``[a]t this time, there is
no evidence that contradicts the taxonomic distinctiveness of P.
longimembris pacificus.''
The traditional scientific approach to defining vertebrate
subspecies has been based almost exclusively on the identification of
morphological differences in body measurements and other morphometric
characters between geographically distinct populations of a species.
Given its apparent, current rarity, limited mobility, and distance from
other subspecies of the little pocket mouse (see, for instance, Meserve
1972; Hall 1981; P. Brylski, in litt, 1993; Erickson 1993) and the
definition and expected course of speciation, it seems reasonable to
assume that the Pacific pocket mouse is now, or will be, a de facto
``full'' species or genetically-isolated taxonomic entity unto itself.
In the absence of current, definitive information to the contrary
from an expert (or any other) source, the Service presently concludes
that the Pacific pocket mouse subspecies constitutes a valid taxon.
Issue 2: The same commenter concluded that the proposed rule must
be withdrawn because the Service improperly and secretly elevated the
species to a category 1 candidate status on the basis of new
information that was obtained in 1993.
Service Response: The three candidate levels (1-3) used by the
Service are administratively defined to periodically advise the public
on the status of various taxa that might come under the protection of
the Act. The terms ``candidate'' or ``category 1'' do not appear in the
Act or implementing regulations in 50 CFR. The Service had previously
notified the public in its candidate notices of review (e.g., 56 FR
58805) that when sufficient information was available, a proposed rule
might result. Section 4(b)(7) of the Act specifically authorizes the
Service to promulgate emergency rules when the well-being of a species
is at significant risk. A species need not be a previously declared
category 1 candidate species to meet the criteria for threatened or
endangered status and to be proposed accordingly or to have an
emergency rule promulgated. For reasons that are fully explored in the
``Summary of Factors'' portions of the February 3, 1994, emergency rule
(59 FR 5306) and this rule, the Service concludes that the Pacific
pocket mouse fully met and still meets the criteria necessary to
promulgate a rule listing the species as endangered.
The new information obtained in 1993 consists of all materials and
data that became available to the Service pertaining to, in part, the
status, distribution, ecology, and biology of the Pacific pocket mouse.
Included in these submittals was an updated manuscript by R. Erickson
(1993). Accompanying this manuscript were records of Pacific pocket
mouse museum or collection specimens and related documentation, raw
data and notes reflecting searches for additional Pacific pocket mice
records, peer-review correspondence, communications with experts in the
field, an updated bibliography, and other, relevant materials. Also
received in 1993 were Brylski's (1993) report and additional
correspondence (P. Brylski, in litt, 1993) that confirmed the
rediscovery of the Pacific pocket mouse on the Dana Point Headlands.
During the prescribed public comment period, the commenter viewed and
photographed or otherwise received all such materials.
Subsequent to an examination of all pre-existing information and
important, additional data received in 1993, the Service concluded that
sufficient data and information existed to list the Pacific pocket
mouse on an emergency basis pursuant to section 4 of the Act and
implementing regulations pertaining thereto. Given the information and
data that has been forthcoming since that time, the Service concludes
that the emergency listing was appropriate and that the species
continues to meet the criteria as an endangered species.
Issue 3: The same commenter observed that the ``* * *[p]roposed
rule should be withdrawn because the Service lacks scientific data to
support a listing of the PPM as threatened or endangered.'' The Service
currently has insufficient information to assess the status and
distribution of the Pacific pocket mouse. Specifically, the commenter
argued ``* * *that a substantial number of trap nights-- perhaps a
minimum of roughly 500--must be employed in any survey effort deemed to
have any relevance for reaching conclusions on presence/absence.
Consistent with this need for reliable data, the M.H. Sherman Company
conducted 643 trap nights during its survey efforts at the Dana
Headlands site.'' The commenter further argued that the majority of
other recent surveys either were conducted ``* * *when the PPM can be
expected to be dormant* * *'' (e.g., Taylor and Tiszler 1991) or at
``[s]ites for which no survey dates are provided (and thus cannot be
considered to provide reliable presence or absence data)* * *'' (e.g.,
the Santa Margarita River Mouth). ``An examination of the data for just
the eight (8) locations historically known to have occupied habitat* *
*reveals a similar lack of information upon which to draw a conclusion
about the appropriateness of listing. The Service's own document
indicates that a live trapping program is needed before the
appropriateness of any listing can be made.'' Another commenter
encouraged the Service ``* * *to fully investigate all remaining
historic habitats as well as potential habitat areas for the Pacific
pocket mouse before making a final determination on its status.'' One
commenter concluded that ``[t]he Service's failure to establish and
publish the accepted survey protocol for the PPM prior to the close of
the public comment period renders this rule-making process invalid.''
Service Response: In response to similar comments regarding the
proposed listing of three Gulf Coast beach mice species (Peromyscus),
the Service (June 6, 1985, 50 FR 23874) argued that ``[i]t is not
necessary to have precise population numbers to determine that the
beach mice are endangered; indeed, it would probably be impossible to
obtain such numbers.'' In that instance, the Service concluded that the
three beach mice were endangered after a thorough review of adequate,
relevant population data and documentation of habitat loss or
perturbation, documented depredation, and other factors affecting the
species.
In consistent fashion, the Service has made every attempt to obtain
the best scientific information and data relating to the status of the
Pacific pocket mouse and the factors affecting that species. Subsequent
to a thorough consideration of these data and information, the Service
concludes that said data and information are adequate and collectively
support a listing as endangered. In particular, a composite of the
relevant data summarized and reported by Hall (1981), Williams (1986),
Williams et al. (1993), and Erickson (1993), the specimen records at
institutions throughout California, and the additional data,
references, and records summarized herein demonstrates that there in
not a paucity of relevant information on the Pacific pocket mouse or
the small rodent species of southern California in general.
An analysis of this very same information reveals that credible
determinations of presence/absence of the Pacific pocket mouse (and
many other small rodent species) depend on a number of factors that are
not a function of the number of survey trap nights. Legitimate small
mammal trappers in California are all licensed by the California
Department of Fish and Game and many possess endangered species permits
from the Service. These scientific surveyors are professionally
obligated and charged with knowing the conditions and circumstances
that will maximize the chances of detecting the Pacific pocket mouse
during focused surveys or otherwise result in an adequate
characterization of the rodent community at any given locale. An
adequate assessment of the appropriate number of trap nights and number
of trapping bouts during a given survey should reflect the experience
of the surveyor and will certainly incorporate, at a minimum, the
results of walk-over surveys for small rodent sign and burrows,
analyses of the size and physical characteristics of the area being
surveyed, the adjudged, current trappability of the target species,
apparent suitability or ``quality'' of site habitat(s), time of year,
phase of the moon, and the climatic conditions. Thus, a given focused
survey for the Pacific pocket mouse may appropriately require far less
than, or far greater than, five hundred trap nights.
All of the above considerations are factored into the Service's
guidelines for surveying the Pacific pocket mouse (U.S. Fish and
Wildlife Service 1994c) and it is likely that the protocol will evolve
pursuant to the recommendations of permitted surveyors and expert
sources. Although the Service has stipulated a minimum of five trapping
bouts at each site to reflect the rarity and possible difficulty in
locating or trapping the Pacific pocket mouse (e.g., Erickson 1993;
Behrends, in litt, 1994), it is further stated that ``[a] lesser effort
may be approved by the Carlsbad Field Office on a case by case basis.''
(U.S. Fish and Wildlife Service 1994c). If, for instance, the objective
is to merely establish presence/absence at a given locale, then a
lesser effort may well be justified if Pacific pocket mice are detected
in the first four trapping bouts. The recent, successful trapping
survey at the Dana Point Headlands is a case in point. Although the
Service concedes that the 643 trap-night effort at that locale in 1993
was justified, in that particular instance, to establish the
approximate range and extent of the local Pacific pocket mouse
population, it is nonetheless true that 9 Pacific pocket mice were
discovered during the first night of trapping subsequent to the
placement of 60 ``effective'' live traps at the site (Brylski 1993).
Even though it is apparent that Pacific pocket mice have not been
recorded in December, January, or February of any given year (see
Erickson 1993) and that the species apparently is most detectable from
April to August (e.g., Meserve 1972), it cannot be assumed that the
species is entirely undetectable during winter months. Subsequent to
his long-term (1969-1973) study of the little pocket mouse at an
elevation of approximately 1,220 meters (4,000 feet) in the Owens
Valley, California, Kenagy (1973) observed that ``[t]he extent of
winter activity in the population of P. longimembris was different in
each of the three winters, ranging from zero to 5 months of activity.*
* *'' Thus, the Service cannot automatically assume that trapping
surveys during winter months are of no value in determining the
presence/absence of the Pacific pocket mouse. If Pacific pocket mice
are active during a given period in winter, however, surface sign
should be visible. In any case, a review of the methodology employed by
Taylor and Tiszler (1991) reveals that ``[t]rapping began in November
of 1988 and was completed May 1989.'' Thus, these authors did conduct
trapping in at least portions of 4 calendar months during which Pacific
pocket mice have been recorded (Taylor and Tiszler 1991; see also
Erickson 1993).
In the emergency rule, R. Zembal, U.S. Fish and Wildlife Service
(pers. comm., 1993), is cited as a source to corroborate the statement
that recent small trapping efforts at the Santa Margarita River Mouth
have failed to detect the presence of the Pacific pocket mouse (59 FR
5307). As is reflected in the Pacific pocket mouse species file at the
Carlsbad Field Office, the referenced communication was ``[t]he Service
has looked repeatedly and intensively for the Pacific pocket mouse at
the Santa Margarita River Mouth in recent years with no success.''
This statement is borne out by records of recent survey and
trapping efforts at that locale. Salata (1981) failed to detect the
Pacific pocket mouse at the Santa Margarita River Mouth on Marine Corps
Base, Camp Pendleton, in dune, pickleweed/saltgrass, pickleweed, and
glasswort/upland grassland habitats during a survey effort in March
1981 that included 188 trap nights. Similarly, the Service (1994a)
reported no captures of the Pacific pocket mouse from June 1986
intermittently to August 1990, during a study of the Santa Margarita
River Mouth that involved a total of 11,380 trap nights and included
surveys of coastal strand, maritime scrub, salt pan, Salicornia upland,
Salicornia/Distichlis habitats, and Salicornia plots. Repeated trapping
bouts at optimum times and in documented Pacific pocket mice habitats
maximized the possibility of detecting the species. From 1986 to 1987,
for instance, coastal strand habitats were surveyed in June, May, and
then again in August for a total of 240 trap nights. In addition,
potential habitat in maritime scrub, Salicornia upland, Salicornia/
Distichlis dominated areas, and Salicornia plots were surveyed during
the same calendar months for a total of 2,040 trap nights. Trapping
bouts in all of the above-mentioned habitats during October of 1986 and
February of 1987 resulted in additional 1,320 trap nights of survey
data.
The Service document referenced by the commenter, a draft proposal
calling for a live trapping program, is not on letterhead, not dated,
and not signed by a Service Field Supervisor or person acting on his or
her behalf. Although the date of the document is unknown, Service staff
recall that this document has been in the files since at least November
1991. Thus, this draft document predates the receipt or filing of all
of the substantive data and scientific papers that were received in
1993 and 1994.
Given all of the information that was received in 1993 and the
additional information and materials that have been received since, the
Service concludes that sufficient, adequate data are available to
assess the likely status and distribution of Pacific pocket mice at the
remaining historic locales and elsewhere throughout its historic range.
The known present and past status and distribution of the Pacific
pocket mouse at these historic locales are again individually reviewed
below in the ``Summary of Factors Affecting the Species'' section of
this rule.
Issue 4: The data used by the Service to estimate the remaining
potential habitat of the Pacific pocket is inadequate. In particular,
``* * * the Service's data for San Diego County, Oberbauer and
Vanderwier (1991), turns out, upon inspection, to consist of nothing
more than unsubstantiated speculation on the part of two individuals.''
Service Response: The Service considers Oberbauer and Vanderwier's
(1991) published evaluation of the present, depleted status of
vegetation communities in San Diego County to be amongst the best
available scientific information on the subject. Given the data base
and expertise at the disposal of The Department of Planning and Land
Use for the County of San Diego, the Service has no reason to doubt the
validity of the presented data. No data or analysis have been submitted
to refute their findings. By contrast, the data, analyses, and
conclusions presented by Soule et al. (1992), summarized by the Service
(March 30, 1993; 58 FR 16742), and the relevant references cited
therein are corroborative.
The Service further concludes that the reported, extreme reduction
in the potential range and extirpation of the Pacific pocket mouse in
Los Angeles County is corroborated by a recent assessment of the land
use status of low-elevation lands therein. In the final rule listing
the coastal California gnatcatcher (Polioptila californica californica)
as threatened (March 30, 1993; 58 FR 16742), it was reported that over
96 percent of the habitat below 250 meters (800 feet) that might have
supported the gnatcatcher have been largely or entirely developed.
Although the coastal California gnatcatcher is sympatric with the only
known, confirmed population of Pacific pocket mouse on the Dana Point
Headlands (EDAW 1993), the latter species has not been documented above
approximately 180 meters (600 feet) (Erickson 1993) and apparently does
not extend nearly as far inland as the former species (summarized March
30, 1993; 58 FR 16742). Thus, given the intense, almost complete
development of the immediate coast in Los Angeles County, the Service
believes that it is reasonable to predict that the past reduction in
the range of the Pacific pocket mouse there exceeds the corresponding
reduction in the Los Angeles County range of the coastal California
gnatcatcher.
Issue 5: ``The Service should explain that with only 8 known
historic locations of the PPM and considering the available data on the
animal, the PPM may never have been abundant in either the number of
populations in the United States or the number of individuals in those
populations, at least for the last hundred years.'' In support of this
position, the commenter also notes that Stephens (1906) described the
Pacific pocket mouse as ``one of the rarest animals.'' The commenter
additionally indicates that ``[t]he Service should also explain that
the PPM may be much more abundant and widespread than suggested in the
[p]roposed [r]ule.''
Service Response: Because the Pacific pocket mouse range-wide has
been variously described as ``exceedingly difficult to catch'' with
snap traps (von Bloeker 1931a) or ``quite trappable'' once located (R.
M'Closkey, pers. comm., 1994; P. Meserve, pers. comm., 1994; R.
MacMillan, pers. comm., 1994), the Service concludes that this anomaly
is generated as a result of the patchy distribution of the species and
its ecological requirements (e.g., M'Closkey 1972; Meserve 1976b; P.
Meserve, pers. comm., 1994; R. M'Closkey, pers. comm., 1994; R.
MacMillan, pers. comm., 1994; P. Brylski, in litt, 1994). Apparently,
the ``* * * rareness of the Pacific pocket mouse is not an artifact of
low trappability * * *'' (P. Brylski, in litt, 1994). Even in an area
(the San Joaquin Hills) where the Pacific pocket mouse was repeatedly
located and studied during two research investigations of the ecology
of the local rodent community, the species was described there as rare
(M'Closkey 1972) or present in relatively low numbers (P. Meserve,
pers. comm., 1994).
Accordingly, given a composite of the available information and
data, the Service concludes that there are no data, substantive or
otherwise, that support the hypothesis that the Pacific pocket mouse is
much more abundant and widespread than suggested in the proposed rule.
Although the persistence of the Pacific pocket mouse on 45 acres of
occupied or potentially-occupied habitat (Brylski 1993) suggests the
real possibility that populations of the species exist elsewhere,
confirmed extant populations away from the Dana Point Headlands have
not been found or rediscovered in over 20 years. Thus, given the range-
wide survey data and all other relevant information now available, the
Service concludes that the Pacific pocket mouse is a patchily
distributed species that has been described as locally abundant (Bailey
1939) to rare on carefully studied plots. Further, this mouse has
become increasingly rare as a result of human-induced, direct impacts
that are presented and discussed in the ``Summary of Factors Affecting
the Species'' section of this rule.
Issue 6: The same commenter observed that ``[t]he Service
mischaracterizes the threat to the Dana Headlands PPM population
because the development of the site is not imminent and any threat
posed by feral or domestic cats cannot be effectively ameliorated by a
listing; accordingly, the [e]mergency [r]ule is improper.''
Service Response: The Service acknowledges that the development of
the Dana Point Headlands currently is not as imminent now as it
appeared in February of 1994. Since the publishing of the emergency and
proposed rules, the citizens of Dana Point have forced a referendum on
the proposed project that apparently will be decided in November of
1994. The referendum and subsequent possible City of Dana Point actions
could result in the delayed implementation of, or modifications to, the
proposed project. The commenter has agreed, however, that ``* * * the
Dana Headlands site is the only location recently shown to contain
PPM'' and that the landowners are requesting approval of a specific
plan that includes ``* * * development on and near the area where the
PPM was trapped in 1993.''
The Service disagrees that the documented predation by domestic and
feral cats cannot be effectively ameliorated by a listing. The mission
and mandate of the Service is to recover listed species utilizing the
funds and authority that Congress provides. A recovery plan for the
Pacific pocket mouse will almost certainly provide for means and
measures to prevent or reduce the depredation of the species. The
Service hopes and trusts that it will be able to enlist the cooperation
of all landowners and cat owners in or near occupied or suspected
Pacific pocket mouse habitat to prevent the continuing endangerment or
extinction of the species.
Issue 7: The same commenter concluded that listing of the Pacific
pocket mouse is not warranted because a comprehensive survey for the
species has not been done in Baja California, Mexico.
Service Response: The Service finds no scientific basis for
concluding or speculating that a possible population or populations of
Pacific pocket mice in Mexico preclude the need to list the species.
Although the range map in Hall (1981) suggests that the range of the
Pacific pocket mouse may extend into northwestern Baja California,
Mexico, there are no known records of the species outside of California
and, thus, the United States as a whole (Hall 1981; Erickson 1993;
Williams et al. 1993). By contrast, an analysis of species limits maps
(Hall 1981) and composite of documented records (Hall 1981; Williams et
al. 1993) reveals that at least 12 small rodent species have been
historically recorded on the coast of northwestern Baja California in
San Quintin, Ensenada, or their environs, to wit: Perognathus baileyi,
Perognathus arenarius, Perognathus fallax, Dipodomys agilis, Dipodomys
merriami, Dipodomys gravipes, Reithrodontomys megalotis, Onochomys
torridus, Peromyscus californicus, Peromyscus maniculatus, Microtus
californicus, and Neotoma fuscipes. Consequently, the best available
data does not support the conclusion that the Pacific pocket mouse may
occur in Mexico. Delaying listing until surveys outside of the known
range had been completed would not be in keeping with the purposes of
the Act.
Even if the Pacific pocket mouse occurs in coastal Baja California,
it is likely that the species does not occur south of 30 deg. north
latitude, which represents an important transition zone for various
birds, plants, land mammals, and other animal taxa. If, in an extreme
case, it is true that the species is patchily distributed southward to
30 deg. north latitude, the Service, pursuant to analyses and
subsequent conclusions reached prior to the listing of the coastal
California gnatcatcher, presently concludes that the United States
historic distribution of the Pacific pocket mouse would represent a
significant portion of the species' overall (hypothetical) range (see
58 FR 16742).
Issue 8: ``Although the Pacific pocket mouse is not one of the
identified species in the State's [Natural Communities Conservation
Planning] program, it may be included in the subregional NCCP for this
area.'' The County of Orange has been provided with updated habitat
information and the subregional plan is currently being prepared.
Therefore, ``* * * the characterization of the NCCP program as
`inadequate' may be premature.''
Service Response: The only use of the word ``inadequate'' in the
proposed or emergency rules (59 FR 5306) refers to the previously
proposed program to control domestic cat predation on the Dana Point
Headlands and not to the State's NCCP program. As currently proposed,
the NCCP program may, in fact, eventually result in the conservation of
the Pacific pocket mouse or the species' potential habitat. At the
present time, however, it remains true that Pacific pocket mouse is not
an NCCP target species and no subregional plans or individual plans
have been completed or implemented that would provide for the
protection of the only known, confirmed population or the conservation
of the species as a whole.
Issue 9: The proposed relocation of the only confirmed population
extant is not a viable conservation alternative for the species.
Service Response: Given the apparent rarity of the Pacific pocket
mouse and the experimental nature of relocation programs, the Service
would carefully review any proposal to relocate--in whole or in part--
any population of the Pacific pocket mouse. It remains true that one of
the central purposes of the Act is to protect the natural habitat of
the listed species. However, if and when Pacific pocket mouse
population levels allow, the Service likely will investigate the
possibility and feasibility of translocating animals to historically-
occupied locales or other areas with suitable habitat and attributes to
affect the recovery of the species or, in an extreme case, prevent
extinction. Pursuant to the requirements of the purpose and section 7
of the Act, the Service likely would solicit the cooperation and
participation of all Federal agencies and landowners in this regard.
Issue 10: The listing of the Pacific pocket mouse may be in
conflict with Federal statutory authority (22 U.S.C. 277d-32) and
important Federal, international wastewater treatment and flood control
projects along the Tijuana River that will diminish threats to public
health and safety.
Service Response: Several recent surveys conducted in the Tijuana
River Valley (e.g., U.S. Fish and Wildlife Service 1994b) have not
resulted in detections of the Pacific pocket mouse. Therefore, given
the best scientific information available, the listing of the Pacific
pocket mouse apparently will not conflict with the proposed projects.
Even if the Pacific pocket mouse is rediscovered in the Tijuana River
Valley or found elsewhere in Federal project ``action areas,'' as
defined at 50 CFR 402.02, the Act provides, under prescribed
circumstances involving public health and safety, for expedited
emergency consultations.
Issue 11: The Service must comply with Executive Order No. 12630
and conduct a takings analysis before reaching any final decision on
listing the Pacific pocket mouse. The commenter noted that the
executive order ``* * * requires the preparation and consideration of a
Takings Implication Assessment (`TIA') by a United States executive
agency before that agency takes actions which may result in a taking of
private property for which compensation may be due under the Fifth
Amendment of the Constitution.''
Service Response: In accordance with 16 U.S.C. 1533(b)(1)(A) and 50
CFR 424.11(b), listing decisions are made solely on the basis of the
best scientific and commercial data available.
In adding the word ``solely'' to the statutory criteria for listing
a species, Congress specifically addressed this issue in the 1982
amendments to the Act. The addition of the word ``solely'' was intended
to remove from the process of the listing or delisting of species any
factor not related to the biological status of the species. It was
determined by a congressional committee that economic considerations
have no relevance to determinations regarding the status of species.
The application of economic criteria to the analysis of these
alternatives and to any phase of the species listing process is
applying economics to the determinations made under section 4 of the
Act and was specifically rejected by the inclusion of the word
``solely'' in the legislation (see H.R. Report No. 567, part I, 97th
Congress, 2d Session 20 [1982]).
Therefore, the Service concludes that it cannot consider a ``TIA''
until a final decision has been made whether or not to list a proposed
species. However, with the signing and publication of this rule in the
Federal Register, the Service will complete and consider a TIA.
Summary of Factors Affecting the Species
After a thorough review and consideration of all available
information, the Service has determined that the Pacific pocket mouse
should be classified as an endangered species. Procedures found at
section 4(a)(1) of the Act (16 U.S.C. 1533) and regulations (50 CFR
part 424) promulgated to implement the listing provisions of the Act
were followed. A species may be determined 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 Pacific pocket
mouse (Perognathus longimembris pacificus) are as follows:
A. The present or threatened destruction, modification, or
curtailment of its habitat or range. The Pacific pocket mouse
historically was recorded and confirmed at eight locales encompassing
some 29 specific trapping stations or sites (see Erickson 1993).
Currently, however, the Pacific pocket mouse is known to exist at only
one site on the Dana Point Headlands, City of Dana Point, Orange
County, California. Although the Dana Point Headlands have not been
developed or significantly altered since the Pacific pocket mouse was
detected at this locale, the ``* * * landowners are requesting approval
on a specific plan from the City of Dana Point, which plan envisions
development on and near the area where PPM were trapped in 1993'' (A.
Hartzell, Attorney-at-Law, in litt, 1994; see also EDAW 1993 and City
of Dana Point, in litt, 1994).
The recent status of the Pacific pocket mouse and its habitat has
been summarized by Erickson (1993) based on a comprehensive search for
museum specimens and capture records and conversations with pocket mice
researchers and recognized expert sources. Other records and
information have been obtained by the Service and made part of the
public record pertaining to this action. A composite of this
information is arranged by county and summarized below:
Los Angeles County. The Pacific pocket mouse historically was
detected in three areas--Marina del Rey/El Segundo, Wilmington, and
Clifton. Two of the three historic locales for the Pacific pocket mouse
(Clifton and Wilmington) in Los Angeles County have been developed
(Erickson 1993). The Service is unaware of potential Pacific pocket
mice habitat at these two locales; none was disclosed or revealed as a
result of the Service's request for information. The third historic
locale (Marina del Rey/El Segundo) apparently has been substantially
altered since the species was last detected there (Erickson 1993; P.
Brylski, in litt, 1993). The Hyperion area, which formerly contained
relatively large expanses of coastal strand and wetland habitats, has
been extensively developed. Although potential habitat remains at the
El Segundo Dunes, walk-over and trapping surveys by J. Maldonado and P.
Brylski, including a 366-trap-night effort in July of 1993, have caused
the latter surveyor to conclude that is ``unlikely'' that the Pacific
pocket mouse occurs there (P. Brylski, in litt, 1993).
Elsewhere in Los Angeles County, a focused survey for the Pacific
pocket mouse in Culver City consisting of 600 trap nights over three
nights in June of 1991 in remnants of appropriate habitat resulted in
no detections of Pacific pocket mice (P. Kelly, pers. comm., 1994).
Although patches of suitable habitat apparently remain on the Palos
Verdes Peninsula and trapping surveys of at least two sites are
recommended, walk-over surveys of two other areas with suitable habitat
by P. Brylski and S. Dodd revealed no pocket mouse burrows or diggings
(P. Brylski, in litt, 1993).
It remains true that there have been no records of the Pacific
pocket mouse in Los Angeles County since 1938 (Erickson 1993; see also
Brylski, in litt, 1993). Given the available information at that time,
Williams (1986) concluded that it was probable that all populations
north of the San Joaquin Hills in Orange County were extirpated.
Orange County. The Pacific pocket mouse has been confirmed at two
locales in Orange County: the San Joaquin Hills and Dana Point.
Development of the ``Spyglass Hill'' area in the San Joaquin Hills
began in 1972 and has resulted in the destruction of the site where the
Pacific pocket mouse and a number of other small rodent species were
studied for a three-year period (P. Meserve, pers. comm., 1994; R.
M'Closkey, pers. comm., 1994; R. MacMillan, pers. comm., 1994; see also
M'Closkey 1972 and Meserve 1972). Prior to the rediscovery of the
Pacific pocket mouse in 1993 on the Dana Point Headlands (Brylski
1993), the last record of the species was from ``Spyglass Hill'' in the
San Joaquin Hills in 1971 (see Erickson 1993). Recent June to October
trapping efforts totaling 1197 trap nights in the San Joaquin Hills and
adjacent Laguna Canyon were unsuccessful in detecting the Pacific
pocket mouse (Erickson, pers. comm., 1993).
Elsewhere, extensive, recent small mammal surveys of the coast of
Orange County away from the Dana Point Headlands have not resulted in
the detection of the Pacific pocket mouse. For instance, no Pacific
pocket mice were detected during 54 trapping bouts conducted from 1979
to 1994 during calendar months from March to October at a total of 24
different locales in coastal Orange County, including areas in or near
Corona del Mar, Crystal Cove State Park, Laguna Beach, and San Clemente
(J. Webb, in litt, 1994). Additional trapping efforts during late fall
or winter months at some of these same locales resulted in the capture
of a variety of other native small rodent species but no Pacific pocket
mice.
A focused trapping survey of appropriate habitats involving a total
effort of 558 trap nights during April of 1990 did not result in the
detection of the Pacific pocket mouse along Aliso Creek (Jones and
Stokes 1990). R. MacMillan (pers. comm., 1994) also did not detect the
Pacific pocket mouse during a June, 60-trap night, survey of suitable
habitat in South Laguna Beach and mentioned that an additional survey
in Alta Laguna conducted for the City of Laguna Beach was unsuccessful.
Surveys contributing to a total effort of 1067 trap nights conducted
elsewhere within the potential Orange County range of the Pacific
pocket mouse during calendar months from April through November
resulted in no detections of the species (Erickson, pers. comm., 1993).
The only known population of the Pacific pocket mouse has persisted
on the Dana Point Headlands in southern, coastal Orange County. Given
the data and analysis presented by Brylski (1993), it is apparent that
25 to 36 Pacific pocket mice occupied approximately 3.75 acres of
habitat within a coastal sage scrub community at that locale in 1993.
As is discussed above, this population is located on land that is under
consideration for development (City of Dana Point, in litt, 1994; EDAW
1994).
San Diego County. The Pacific pocket mouse historically has been
detected at three general locales in San Diego County: the San Onofre
area, Santa Margarita River Estuary, and the lower Tijuana River
Valley. Although portions of the San Onofre area are relatively
undisturbed and deserving of further attention (e.g., P. Brylski, in
litt, 1994), recent small mammal trapping efforts at the locale failed
to detect the presence of the Pacific pocket mouse (Erickson 1993; R.
Erickson, pers. comm., 1993).
As is reflected in the Service's response to ``Issue 3'' in the
``Summary of Comments and Recommendations'' section of this rule,
recent, intense survey efforts at the Santa Margarita River Mouth
similarly have not resulted in any Pacific pocket mouse detections
(Salata 1981; U.S. Fish and Wildlife Service 1994a; see also Zembal
1984). Although the relatively undisturbed coastline of Marine Corps
Base Camp Pendleton ``* * * probably provides the best chance for the
survival of the subspecies'' (Erickson 1993), the Base Environmental
and Natural Resources Management Office has indicated that ``[o]ther
than the recorded documentation of this species in the vicinity of San
Onofre and the Santa Margarita Estuary in the 1930's * * * we have no
information regarding the occurrence of this species aboard Marine
Corps Base Camp Pendleton. To date, none of the environmental studies
which have occurred aboard the Base since that time have identified
this species.'' (L. Armas, in litt, 1994).
During the 1930's, Camp Pendleton Marine Corps Base did not exist
and the city of Oceanside was immediately adjacent to the Santa
Margarita River Estuary. Much of the southern half of the Santa
Margarita River Estuary was destroyed in the early 1940's during the
establishment of Marine Corps Base Camp Pendleton and the related
construction of a boat basin and harbor facilities. In addition, the
Oceanside area has been extensively developed since the Pacific pocket
mouse was last recorded there in 1931 and the Service is aware of
little, if any, remaining suitable habitat in that jurisdiction.
The lower Tijuana River Valley, which accounts for approximately 35
percent of all specimen records (Erickson 1993), evidently supported a
relatively large population of the Pacific pocket mouse in historic
times (e.g., von Bloeker 1931b). Citing two recent, unsuccessful
trapping efforts (Taylor and Tiszler 1991; R.T. Miller, pers. comm.,
1993), Erickson (1993) commented that the remaining habitat there is
possibly insufficient to support the species. Most recently, the U.S.
Fish and Wildlife Service (1994b) conducted a focused survey for the
Pacific pocket mouse in the Tijuana River Valley from April 18, 1994 to
May 13, 1994. Despite walk-over surveys of the area, four or five
trapping bouts in each of eight separate locales, and a total of 4,242
trap nights of survey effort, no Pacific pocket mice were detected.
Elsewhere in San Diego County, a small mammal trapping program that
began in 1987 is continuing at Torrey Pines State Park in habitats that
have ranged from maritime chaparral to open (barren) areas as a result
of two prescribed burns in the project area. Since 1988, 88 traps have
been set every other week from mid-March to October during the study
period. Despite an effort that now exceeds 7,500 trap nights, no
Pacific pocket mice have been detected (R. Dingman, pers. comm., 1994).
Analysis of the relevant data reveals that the habitat and
potential range of the Pacific pocket mouse apparently have been
significantly reduced in the recent past. Opportunities to find
additional populations of the Pacific pocket mouse apparently are
limited as a result of the extent of land development in coastal
southern California (Service files).
Based on the best available scientific information, the Service
considers the historic, known range of the Pacific pocket mouse to
encompass a 3.2-km (2-mile) wide band along the immediate coast of Los
Angeles, Orange, and San Diego Counties from Marina Del Rey/El Segundo
south to the international border. Most native habitats within 3 km (2
miles) of the coast in Los Angeles, Orange and San Diego counties have
been converted to urban and agricultural uses (Service files).
Specifically, less than 400 hectares (1,000 acres) or 1 percent of
approximately 28,000 hectares (69,000 acres) that encompass the
projected range of the Pacific pocket mouse in Los Angeles County are
undeveloped (Service files). In Orange County, about 17,600 hectares
(43,500 acres) or 81 percent of approximately 21,600 hectares (53,500
acres) encompassing the projected range of the species have been
developed (Service files). Oberbauer and Vanderwier (1991) reported
that 72 percent of the original coastal sage scrub, 94 percent of
native grasslands, 88 percent of coastal mixed chaparral, 88 percent of
coastal salt marsh, 100 percent of coastal strand, and 92 percent of
maritime sage scrub habitats in San Diego County had been converted to
urban and agricultural uses by 1988.
Although the historic distribution of the coastal sage scrub
element of Pacific pocket mouse habitat was undoubtedly patchy to some
degree, this condition evidently has been greatly exacerbated by urban
and agricultural development. All of the published literature on the
status of coastal sage scrub vegetation in California supports the
conclusion that this plant community is one of the most depleted
habitat types in the United States (Service files). In a broader
context, the California floristic province, which is recognized as a
separate evolutionary center by botanists, is identified by Wilson
(1992) as one of the recognized world ``hot spots,'' which are defined
to be ``* * * habitats with many species found nowhere else and in
greatest danger of extinction from human activity.'' The California
floristic province is the only designated ``hot spot'' in North America
and Mexico (Wilson 1992).
The available information further suggests that the quantity of
potential Pacific pocket mouse river alluvium substrates have
significantly declined since the species was last recorded in numbers
in the 1930's. With few exceptions (such as the Santa Margarita River),
essentially all of the rivers and creeks within its historic range are
now partially or completely channelized. In many cases (e.g., Los
Angeles River, San Gabriel River, Santa Ana River) stream and sediment
flows are regulated or inhibited by dams, reservoirs or other water
conservation or impoundment facilities (see also Erickson 1993).
Although some suitable Pacific pocket mouse habitat apparently
remains in San Onofre and contiguous coast of Marine Corps Base Camp
Pendleton, the San Joaquin Hills, the Palos Verdes Peninsula, the El
Segundo Dunes and at scattered locales elsewhere in the historic range
of the species, this habitat is becoming increasingly scarce and likely
will continue to be destroyed, disturbed or otherwise impacted as a
manifest result of human activities. Williams (1986) concluded that
habitat losses resulting from off-road vehicle activities, highways,
and urbanization likely were extensive. Erickson (1993) observed that
industrial and agricultural development likely were additional factors
contributing to the decline of the species. More recently, the Service
(1994b) reported that habitats or lands in a historically-occupied
Pacific pocket mouse locale apparently have been impacted by artificial
lighting, disking or blading, the presence of non-native rodent species
(see also Soule et al. 1992), and pedestrian and horse traffic. The
Pacific pocket mouse, as a representative heteromyid rodent, may be
more susceptible to the adverse effects of the human presence than
cricetid rodents (R. MacMillan, pers. comm., 1994).
Although it is possible that fire may intermittently create or
sustain Pacific pocket mouse habitat mosaics, it has been reported that
increased fire frequency may contribute to the type conversion of
coastal sage scrub to grassland habitats (Service files). In addition,
the Service acknowledges that the protection of lives and property may
require fire prevention strategies that do not necessarily result in
the maintenance or creation of potential Pacific pocket mouse habitat.
Accordingly, the Service concludes that fire prevention measures and
unnaturally high fire frequencies resulting from anthropogenic
ignitions may directly or indirectly impact the Pacific pocket mouse.
Equally, if not more, problematical than habitat disturbance or
destruction, however, has been an increasing degree of habitat
fragmentation in coastal southern California (e.g., Soule et al. 1992;
Service files), which is known generally to reduce habitat quality and
promote increased levels of local extinction (e.g., Terborgh and Winter
1980; Wilcox 1980; Ehrlich and Ehrlich 1981; Wilson 1992; Bolger et al.
1994 in press). Given the location of the research areas and thrust and
direction of the investigations, the research and findings of Soule et
al. (1992) are particularly relevant to a discussion of fragmentation
effects on the Pacific pocket mouse.
Based on studies of native bird, rodent and flowering plant species
persistence in chaparral and coastal sage scrub habitat remnants in
coastal San Diego County, California, Soule et al. (1992) concluded
that ``[t]he effects of fragmentation in a scrub habitat in California
on three taxa (plants, birds, and rodents) are concordant. Extinctions
within the habitat remnants occur quickly and the sequence of species
disappearances of birds and rodents is predictable based on population
density in undisturbed habitat.'' Terborgh and Winter (1980) observed
previously that ``[r]arity proves to be the best index of
vulnerability.''
Bolger et al. (1994, in press) concluded that ``[f]ragments support
fewer species [of native rodents] than equivalently sized plots in
large plots of unfragmented chaparral indicating that local extinctions
have occurred following insularization.'' Given a composite of the
available data on the local status and distribution of select species
within the study area in coastal San Diego County, Soule et al. (1992)
remarked that it was possible to assess with reasonable accuracy the
date that a particular habitat remnant became isolated.
Soule et al. (1992) further noted that ``* * * urban barriers
including highways, streets, and structures, impose a very high degree
of isolation.'' Similarly, Ehrlich and Ehrlich (1981) observed that
``smaller animals may also suffer fragmentation of their populations by
highways, railways, canals, etc., changing population structures and
making the remaining populations smaller and more subject to random
extinction. One study has indicated that a four-lane divided highway
may be a barrier to the movement of small forest mammals equivalent to
a river twice as wide.'' (Ehrlich and Ehrlich 1981). Although not a
forest animal, the Pacific pocket mouse must be now considered rare by
any standard and, therefore, particularly vulnerable to the effects of
continuing habitat destruction and fragmentation (see Terborgh and
Winter 1980).
Largely on the bases of significant habitat loss and fragmentation
in coastal California, the Service has listed several other species of
plants and animals as endangered or threatened, including the
California least tern (Sterna antillarum browni), light-footed clapper
rail (Rallus longirostris levipes), the Palos Verdes blue butterfly
(Glaucopsyche lygdamus palosverdesensis), El Segundo blue butterfly
(Euphilotes battoides allyni), and, most recently, the coastal
California gnatcatcher (58 FR 16742; Service files). The Service listed
the coastal California gnatcatcher, because of, in part, the
significant and ongoing destruction, perturbation, or fragmentation of
that species' coastal sage scrub habitat (58 FR 16742).
B. Overutilization for commercial, recreational, scientific, or
educational purposes. Although the existing information and data are
not conclusive, P. Brylski (pers. comm., 1994) has commented that
scientific collecting in the 1930's may have substantially impacted the
Pacific pocket mouse population in the El Segundo area. Erickson (1993)
reported the existence of 78 specimens collected in ``Hyperion'' (now
Marina del Rey/El Segundo) during the fall of 1931 and spring of 1932.
Otherwise, there is no substantive information that this factor is
applicable.
C. Disease or predation. The expressed, perhaps synergistic effects
of habitat fragmentation and the proximity of urban environments to
Pacific pocket mouse habitats are likely to increase the rate of
depredation on that species. Most recently, Soule et al. (1992) has
confirmed earlier conclusions by noting that ``[t]here is evidence that
large predators retard the biotic collapse of these [habitat] remnants
by controlling populations of smaller, semi-commensal predators,
including domestic cats * * *.''
Several species have been reported as potential or documented
predators of the Pacific pocket mouse, including the red fox (Vulpes
vulpes). The explosive proliferation of non-native populations of red
foxes in coastal southern California is well documented (e.g., Lewis et
al., 1993). Given the relative abundance of the red fox in coastal
southern California (Lewis et al. 1993) and the fact that descriptions
of the diet of red foxes invariably include mice (Ingles 1965; Jameson
and Peeters 1988; Burkett and Lewis 1992; Lewis et al. 1993), it seems
reasonable to assume that ``feral'' foxes similarly could substantially
impact populations of Pacific pocket mice if and when the species
overlap. Erickson (1993) has commented that the red fox ``* * * may
have hastened the demise of pacificus'' in the El Segundo area, a
locale that previously and historically accommodated the Pacific pocket
mouse in numbers.
In addition, feral and domestic cats (Felis catus) are known to be
formidable predators of native rodents (e.g., Hubbs 1951; George 1974;
Frank 1992). Pearson (1964) concluded that the removal of 4,200 mice
from a 14-hectare (35-acre) test plot was accomplished largely by 6
cats over 8 months.
Feral or domestic cats are threatening the only known, confirmed
population of Pacific pocket mouse. Specifically, a resident living
immediately adjacent to the Dana Point Headlands population reported
that domestic cats had recently and repeatedly brought in a number of
``tiny gray mice.'' One such specimen was retrieved and confirmed to be
a Pacific pocket mouse (P. Brylski, in litt, 1993).
D. The inadequacy of existing regulatory mechanisms. Should
protection afforded the Pacific pocket mouse pursuant to the emergency
rule under the Act (59 FR 5306) lapse or otherwise be removed, other
select existing regulatory or conservation mechanisms could possibly
provide some protection for the species. These include--(1) the Act if
the species were to occur sympatrically with a listed species, (2) the
California Natural Community Conservation Planning effort, (3) the
California Environmental Quality Act, (4) land acquisition and
management by Federal, State, or local agencies or by private groups
and organizations, and (5) local laws and regulations.
The Pacific pocket mouse is currently recognized as a Species of
Special Concern ``Of Highest Priority'' by the California Department of
Fish and Game. If emergency protection afforded the Pacific pocket
mouse pursuant to the Act were to be removed prior to the promulgation
of a final rule listing the species as endangered, the species would
retain its status as a proposed species under the Act.
The only known, confirmed population of the Pacific pocket mouse
does occur sympatrically with a population of the threatened coastal
California gnatcatcher (Brylski 1993; EDAW 1993). Under provisions of
section 10(a) of the Act, the Service may permit the incidental take of
the coastal California gnatcatcher during the course of an otherwise
legal activity, provided that the species' survival and recovery in the
wild is not precluded. The issuance of section 10(a) permit to take the
coastal California gnatcatcher on the Dana Point Headlands could result
in the extinction of the Pacific pocket mouse.
In 1991, the State of California commenced the Natural Communities
Conservation Planning (NCCP) program to address the conservation needs
of natural ecosystems throughout the State. The initial focus of that
program is the coastal sage scrub community, which is occupied, in
part, by the Pacific pocket mouse. At the present time, however, no
program plans have been completed or implemented, and no protection is
currently in place or proposed to reduce or eliminate possible, future
impacts to habitat occupied in 1994 by the Pacific pocket mouse on the
Dana Point Headlands, which is the only known, confirmed refugium for
the species.
In many instances, land-use planning decisions in southern
California have been made and continue to be made on the basis of
environmental review documents prepared in accordance with California
Environmental Quality Act and the National Environmental Policy Act.
Although impacts to sensitive species and habitats must be disclosed
pursuant to these statutes, the protection or conservation of the
species or their habitats are at the discretion of the decision makers.
Given a composite of the best available scientific information, it is
clear that these statutes have not adequately protected the Pacific
pocket mouse or its habitat.
Prior to the emergency-listing of the Pacific pocket mouse as
endangered, a relocation program and predator management program were
proposed to mitigate impacts to the Pacific pocket mouse on the Dana
Point Headlands (EDAW 1993). More recently, the City of Dana Point
(City) (in litt, 1994) has indicated that the project applicant must,
if the Pacific pocket mouse is listed, obtain a take permit for the
Pacific pocket mouse prior to the issuance of any city permits ``* * *
that would allow activity that would harm or harass the Pacific pocket
mouse * * *''
Because the Service has not received a formal, detailed mitigation
proposal from the City or project proponent, the Service cannot
presently assess the merits of said proposal or render a judgment as to
whether or not the proposed impact avoidance and mitigation measures
will prevent jeopardy to the Pacific pocket mouse. Although the Service
notes and appreciates the fact that it would be given the opportunity
to review the relocation program if the Pocket mouse is not listed
(City of Dana Point, in litt, 1994), the Service has concluded that the
potential effects of translocation are not relevant to a decision on
whether to list a species. Under section 4 of the Act, if data warrant
listing, the Service must proceed to list the species. The Service (59
FR 5308) and the California Department of Fish and Game (in litt, 1993)
both have independently concluded that the relocation program
previously outlined (EDAW 1993) is inadequate.
E. Other natural or man-made factors affecting its continued
existence. Considering the extremely small population size and current
range of the Pacific pocket mouse (no more than 36 individuals have
been detected in the last 22 years), the current extent of the coastal
strand, coastal dune, river alluvium, and coastal sage scrub habitats
upon which it depends, further losses of habitat will have significant
adverse effects on any extant populations of this species. Given all
relevant data and considerations, it is apparent that the species is
highly susceptible to extinction as a result of environmental or
demographic factors alone (e.g., Mace and Lande 1991).
The Service has carefully assessed the best scientific and
commercial information available regarding the past, present, and
future threats faced by this species in determining to make this rule
final. Based on this evaluation, the Service finds that the Pacific
pocket mouse warrants protection under the Act on the basis of
continuing threats to the species, which include substantial habitat
loss and fragmentation and depredation. Therefore, the preferred and
only possible action is to list the Pacific pocket mouse as endangered,
which is defined in section 3(6) of the Act as a species ``which is in
danger of extinction throughout all or a significant portion of its
range * * *.''
As provided by 5 U.S.C. 553(d), the Service has determined that
good cause exists to make the effective date of this rule immediate.
Delay in implementation of the effective date would place the remaining
Pacific pocket mice and habitat of the species at risk (see relevant
discussion below under the heading of ``Critical Habitat'').
Critical habitat is not being designated at this time for the
reasons discussed below.
Critical Habitat
Critical habitat is defined in section 3 of the Act as: (i) the
specific areas within the geographical area occupied by a species, at
the time it is listed in accordance with the Act, on which are found
those physical or 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, as amended, requires critical habitat
to be designated to the maximum extent prudent and determinable at the
time a species is listed as endangered or threatened. The Service has
concluded that designation of critical habitat is not prudent for the
Pacific pocket mouse at this time. The Service's regulations (50 CFR
424.12(a)(1)) state that designation of critical habitat is not prudent
when one or both of the following situations exist--(1) the species is
threatened by taking or other human activity, and identification of
critical habitat can be expected to increase the degree of such threat
to the species, or (2) such designation of critical habitat would not
be beneficial to the species.
In the case of the Pacific pocket mouse, both criteria are met. A
communication has been received by the Service that effectively
threatens the only known, confirmed population of the species. This
threat was received from an individual who was apparently incensed at
the emergency and proposed listings of the species. On the basis of
this kind of activity, the Service finds that publication of critical
habitat descriptions and maps would likely make the species more
vulnerable to activities prohibited under section 9 of the Act.
Secondly, the only known, confirmed population of the Pacific
pocket mouse is found on private property where Federal involvement in
land-use activities is not expected to occur. Protection resulting from
critical habitat designation is largely achieved through the Federal
consultation process pursuant to section 7 of the Act and the
implementing regulations pertaining thereto (50 CFR 402). Because
section 7 would not apply to many, if any, of the majority of land-use
activities occurring within the species' known habitat, its designation
would not appreciably benefit the species.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Endangered Species 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 local agencies,
private organizations, 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. The protection
required of Federal agencies and the prohibitions against taking and
harm are discussed, 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 the Service 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 insure 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
action may affect a listed species or its critical habitat, the
responsible Federal agency must enter into formal consultation with the
Service. Federal agencies that may be involved through activities they
authorize, fund, or carry out that may affect the Pacific pocket mouse
or its historical habitat include the Army Corps of Engineers, Federal
Highway Administration, the Department of the Navy (including Marine
Corps Base Camp Pendleton).
The Act and implementing regulations set forth a series of general
prohibitions and exceptions that apply to all endangered wildlife. The
prohibitions, codified at 50 CFR 17, 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, or
collect; or attempt any such conduct), import or export, ship in
interstate commerce in the course of commercial activity, or sell or
offer for sale in interstate or foreign commerce any listed species.
The term ``harm'' as it applies to the take prohibition is defined in
50 CFR 17.3 to include an act that actually kills or injures listed
wildlife. Such act may include significant habitat modification or
degradation where it actually kills or injures listed wildlife by
significantly impairing essential behavioral patterns, including
breeding, feeding or sheltering. It also is illegal to possess, sell,
deliver, carry, transport, or ship any such wildlife that has been
taken illegally. Certain exceptions apply to agents of the Service 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 codified at 50 CFR 17.22, and 17.23.
Such permits are available for scientific purposes, to enhance the
propagation or survival of the species, and/or for incidental take in
connection with otherwise lawful activities.
Requests for copies of the regulations on listed wildlife and
inquiries about prohibitions and permits may be addressed to the U.S.
Fish and Wildlife Service, Permits Branch, 911 N.E. 11th Avenue,
Portland, Oregon 97232-4181 (telephone 503/231-6241, facsimile 503/231-
6243).
National Environmental Policy Act
The Fish and Wildlife Service has 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 Endangered Species Act of 1973, as amended. A notice
outlining the Service's reasons for this determination was published 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 U.S. Fish and Wildlife Service, Carlsbad Field Office
(see ADDRESSES section).
Author
The primary author of this final rule is Loren R. Hays, U.S. Fish
and Wildlife Service, Carlsbad Field Office (see ADDRESSES section).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, and 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. Section 17.11(h) is amended by revising and making permanent the
entry for the ``Mouse, Pacific pocket'' under MAMMALS to read as
follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Vertebrate population
-------------------------------------------------- Historic range where endangered or Status When listed Critical Special
Common name Scientific name threatened habitat rules
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mammals
* * * * * * *
Mouse, Pacific pocket... Perognathus U.S.A. (CA)............ Entire................. E 526, 554 NA NA
longimembris pacificus.
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dated: September 23, 1994.
Mollie H. Beattie,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 94-24065 Filed 9-26-94; 11:01 am]
BILLING CODE 4310-55-P
