(DRAFT) - Taxonomy
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

TAXONOMY

NAME - VOLE, AMARGOSA

OTHER COMMON NAMES - VOLE, AMARGOSA; VOLE, DESERT; MOUSE, MEADOW and AMARGOSA

ELEMENT CODE -

CATEGORY - Mammals

PHYLUM AND SUBPHYLUM - CHORDATA,

CLASS AND SUBCLASS - MAMMALIA,

ORDER AND SUBORDER - RODENTIA,

FAMILY AND SUBFAMILY - MURIDAE,

GENUS AND SUBGENUS - MICROTUS,

SPECIES AND SSP - CALIFORNICUS, SCIRPENSIS

SCIENTIFIC NAME - MICROTUS CALIFORNICUS SCIRPENSIS

AUTHORITY -

TAXONOMY REFERENCES -

COMMENTS ON TAXONOMY -
Amargosa Vole

Microtus californicus scirpensis V. Bailey, 1900

KINGDOM: Animal GROUP: Mammal

PHYLUM: Chordata CLASS: Mammalia
ORDER: Rodentia FAMILY: Muridae

The Amargosa vole (Microtus californicus scirpensis) was
originally described as Microtus scirpensis (01), and has been
previously referred to as the Amargosa meadow mouse and as the Desert
vole (01,02). This is a relatively large Microtus (02), with dorsal
coloration ranging from dark buffy gray to pallid neutral gray (01,
02,03). The underside is smokey gray (01). The feet are described as
brownish gray (01), and the tail is distinctly bicolored (01,02).
This subspecies is morphologically similar to other Microtus
californicus spp., and its identity is most certainly determined by
its capture locality. M. c. scirpensis is restricted to a small
geographic area along the Amargosa River in southern Inyo County,
California (03). The average total length, tail length, and hind
foot length of 6 adults specimens were 203 mm, 65 mm, and 25.1 mm,
respectively (01).
The type specimen of M. c. scirpensis is deposited in the U.S.
Taxonomy - 1 (DRAFT) - Taxonomy
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

National Museum, Bureau of Biological Survey Collection (25979/33385,
adult female) along with at least six other topotypes from the
Amargosa River (a spring near Shoshone, near the Nevada State line,
Inyo County, California (01,02)). Four specimens are deposited in the
collection of the Los Angeles County Museum (LACM 5480-5483); all
were collected at Tecopa and Tecopa Hot Springs, Inyo Co. (04). Five
specimens from Tecopa and Tecopa Hot Springs are deposited in the Bird
and Mammal Museum, California State University, Long Beach (04). It
is possible that additional specimens are in the Museum of Vertebrate
Zoology, University of California, Berkeley. A collection of
photographs of both live and dead M. c. scirpensis is owned by V.C.
Bleich; also included in that collection are numerous photographs
depicting the macro- and micro-habitats of the subspecies (06).
Both Bailey (01) and Kellogg (02) provide detailed morphological
descriptions of M. c. scirpensis; Kellogg (02) provides detailed
cranial descriptions. The information provided by these authors is of
little practical value, however, unless skeletal material is available
for study.

Taxonomy - 2 (DRAFT) - Status
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

STATUS

Coded Status

E: Federal Endangered

COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Amargosa vole (Microtus californicus scirpensis) has been
designated aS Endangered pursuant to the Endangered Species
Act of 1973 (50 CFR 17.11; P.L. 93-205, 87 Stat. 884; 16 U.S.C.
1531-1540), as amended. The subspecies has this status wherever
found including the State of California. Critical Habitat has been
designated along the Amargosa River in all portions of Sec. 4,5,9,10,
15,16, and 22 of T20N, R7E and Sec. 28,29,32, and 33, T21N, R7E,
in Inyo County, California (50 CFR 17.95(a)). Major constituent
elements of designated Critical Habitat include marsh vegetation
(primarily bulrushes - Genus Scirpus), springs and some open water
which provide escape cover and adequate food supply or Sec. N-OCCUR.
This subspecies is protected by the Lacey Act (P.L. 97-79, as
amended; 16 U.S.C. 3371 et seq.) which makes it unlawful to import,
export, transport, sell, receive, acquire, or purchase any wild
animal (alive or dead including parts, products, eggs, or offspring):
(1) in interstate or foreign commerce if taken, possessed,
transported or sold in violation of any State law or
regulation; or
(2) if taken or possessed in violation of any U.S. law,
treaty, or regulation or in violation of Indian tribal law.
It is also unlawful to possess any wild animal (alive or dead
including parts, products, eggs, and offspring) within the U.S.
territorial or special maritime jurisdiction (as defined in
18 U.S.C. 7) that is taken, possessed, transported, or sold in
violation of any State law or regulation, foreign law, or Indian
tribal law.

RESPONSIBLE FEDERAL AGENCIES:

USFWS -Responsible for the management/recovery, listing, and
law enforcement/protection of this species.
BLM -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public land under their control (43 CFR 4140). Also
responsible for management/recovery on Bureau of Land
Management lands.

All Federal agencies have responsibility to ensure that any
action authorized, funded, or carried out by that agency is not likely
to jeopardize the continued existence of the species or result in the
destruction or adverse modification of Critical Habitat (50 CFR 402),
and to utilize their authorities to carry out programs for the
Status - 1 (DRAFT) - Status
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

conservation of the species.

STATE STATUSES AND LAWS:

STATE: California
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: Calif. Dept. of Fish and Game
STATE STATUTE: Calif. Endangered Species Act; Fish and Game
Code Chapt. 1.5, Art. 1, Sec. 2050.

INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
None.

ECONOMIC STATUSES:
None.

80/06/18:45 FR 41172/41173 - Petitioned for listing
82/12/30:47 FR 58454/58460 - Listed as a Category 1 species
83/08/29:48 FR 39090/39093 - Proposed listing as Endangered
84/11/15:49 FR 45163/ - Listed Endangered with Critical Habitat

Status - 2 HABITAT ASSOCIATIONS

HABITAT - TERRESTRIAL
INLAND AQUATIC

LAND USE -
Cropland and Pasture
Streams and Canals
Nonforested Wetland

NATIONAL WETLAND INVENTORY CODES

NWI NWICLS NWIMOD NWISPEC

Riverine, lower perennial OW0
Palustrine OW0
Palustrine FL3
Palustrine EM5

COMMENTS ON HABITAT ASSOCIATIONS -
The Amargosa vole is restricted in distribution to those
riparian areas along the Amargosa River near Tecopa Hot Springs and
Tecopa, Inyo County, California. Typically, these areas are
characterized by freshwater marsh vegetation, dominated by Scirpus
spp., Carex spp., and Juncus spp. (01,03,04,05,07,08,09,10). Plant
density ranges from open to dense, topographic relief ranges from
0 to 20 % slope, and water distribution varies from absent to
incised streams, pools, that spread out beneath the plant canopy (04,
05,07,08,09,10).
The earliest description (01) of the habitat of Amargosa voles
was, "Wet ground under tall tules (Scirpus olneyi), where the
runways extend through mud and water...". Recent work (04,05,09) has
substantiated this earlier habitat description and provided additional
information. Voles have sometimes been captured in areas devoid of
water, but with vegetation similar to that described above (05,10).
Their habitat has been described as, "... mud and water
in a little marsh ..." (01). During a recent study released voles
were always observed to scramble into matted Scirpus olneyi (05),
suggesting the potential importance of that material as a cover
requirement. During extensive fieldwork (05,10), no nests of this
subspecies were discovered (06).
Limited information is available on the plant species
composition of marsh areas in which Amargosa voles have been
documented. Rado and Rowlands (09) estimated that plant cover was
dense in two areas which they investigated, and that Scirpus olneyi,
and Carex spp. formed the dominant plant overstory, while Distichlis
spicata, Juncas spp., and Anemopsis californica were important
understory components. Other investigatiors (05,10) noted that the
density of Scirpus olneyi was moderate to high in areas from which
voles were trapped; some areas having moderate to high Scirpus
densities yielded no voles, however. In no instance did these
investigators find voles in areas they described as having "low"
densities of Scirpus.
Based on ocular inventories, Bleich (05) noted that the
descriptions supplied by other investigators (12,13) for vegetation
at nearby Saratoga Springs, Death Valley National Monument, was
similar to that in areas inhabited by M. c. scirpensis along the
Amargosa River.

Habitat Associations - 1 (DRAFT) - Food Habits
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

FOOD HABITS

TROPHIC LEVEL -
HERBIVORE

LIFESTAGE FOOD FOOD PART
General Arthropods
General Carrion
General Vascular Plants-Emergent Nonwoody
General Roots/Tubers/Rhizomes-Herbaceous
General Poaceae
General
General Forb Leaves/Stems
General Forb Flowers/Fruit/Seed

Food Habits - 1 (DRAFT) - Environment Associations
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

ENVIRONMENTAL ASSOCIATIONS

G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae

LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G
G Aquatic Features: Pool areas
G Aquatic Features: Springs [flowing]

Environment Associations - 1 (DRAFT) - Life History
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

LIFE HISTORY

FOOD HABITS:
No information exists with respects to the food habits of the
Amargosa vole. The abundance of "chewed off" stems of Scirpus
olneyi suggests that S. olneyi may be a food source (06). The
Amargosa vole probably subsists primarily on vegetation (grasses,
leaves, and stems in winter; grasses, seeds and forbs in summer) as
do other subspecies of M. californicus (22,25). That diet probably
is supplemented occasionally with animal matter (insects and carrion),
as are the diets of other species of Microtus (14,15).
Five intestinal tracts, preserved in alcohol, are deposited in
the Bird and Mammal Museum, California State University, Long Beach;
no analysis of these materials have been undertaken.

HOME RANGE/TERRITORY:
It is unlikely that the Amargosa vole exhibits true territorial
behavior; however, intraspecific agonistic behavior has been
documented in Microtus (16,17). Fourteen different Amargosa voles
were captured within an area measuring 20 x 30 meters, suggesting
that overlap of home ranges does occur. Eleven of the 14 individuals
were juveniles (05).
Two juvenile Amargosa voles demonstrated movements of
approximately 25 meters between recaptures (05). Microtus
californicus typically has a small home range (18), and the best
estimate of the average maximum distance between captures of
individuals was 60 feet in another study (19). The limited
information available (05) for Amargosa voles appears to be consistent
with findings for the species in general.
Lidicker (35) has provided a detailed discussion of the social
biology of Microtus californicus in general.

PERIODICITY:
Amargosa voles have been captured during December, February,
March, and April (01,05,09,10). They probably are active year round,
and the absence of summer captures probably reflects a lack of
trapping effort (06).
Twenty of 38 captures reported by Bleich occurred during daylight
hours, suggesting approximately equal levels of diurnal and nocturnal
activity (05).

MIGRATION PATTERNS:
The Amargosa vole is not thought to be migratory (06).

COVER/SHELTER REQUIREMENTS:
Nothing is known of the cover and shelter requirements of this
subspecies. Their habitat has been described as, "... mud and water
in a little marsh ..." (01). During a recent study released voles
were always observed to scramble into matted Scirpus olneyi (05),
suggesting the potential importance of that material as a cover
requirement. During extensive fieldwork (05,10), no nests of this
subspecies were discovered (06).

Life History - 1 (DRAFT) - Life History
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

REPRODUCTIVE SITE REQUIREMENTS:
Previous field investigations (01,05,09,10) have yielded no
information on reproductive site requirements of the Amargosa vole.

REPRODUCTIVE CHARACTERISTICS:
The gestation period in Microtus californicus is approximately
three weeks, and litter size ranges from 1 to 9, with a mean of about
4 (20). The female may ovulate and breed within 15 hours after
parturition; weaning of the young occurs at about two weeks of age
(20). Reproduction occurs from September through June, with peaks in
November and April (19,25). Photoperiod length has been shown to
affect the testicular cycle in male M. californicus (21).
The Amargosa vole probably exhibits reproductive characteristics
similar to those of the species as a whole (06). Juveniles have
been captured during April, December (05,10), and February (01).
The large number of juveniles reported captured in December would be
consistent with peak reproduction during November (05,19,25).

PARENTAL CARE:
No data is available on parental care by M. c. scirpensis. In
M. californicus, between 1 and 9 are born, and avergae litter size is
about 4; the young are weaned at two weeks of age (20). It is likely
that M. c. scirpensis exhibits characteristics similar to those found
in other subspecies of M. californicus (06). Lidicker (36) has
provided detailed information on the social biology of Microtus
californicus in general.

POPULATION BIOLOGY:
Microtine rodents characteristically undergo radical population
fluctuations (23). Population cycles occuring every three to four
years have been documented for M. californicus in general (24).
Litter size averages about 4 (20), and females may produce 4-6
litters per breeding season (29). Krebs (37) has provided detailed
demographic data for M. californicus in general; it is possible that
his findings may be applicable to M. c. scirpensis, but that is
speculative. Selective pressures resulting from the radically
different environmental conditions under which M. c. scirpensis lives
(02) may have resulted in different life history strategies (06).
Predators inhabiting areas occupied include coyotes (Canis
latrans), kit fox (Vulpes macrotis), and bobcat (Lynx rufus) (30).
Several species of hawks and owls also occur in the area, and the
remains of microtines have been recovered from the castings of these
birds (06,31).
For M. c. scirpensis, the importance of bulrush-dominated
habitat located on higher ground not susceptible to flooding has
been recognized (09). Such sites could serve as points from which
reestablishemnt of populations in low lying areas occurs after
flooding (09). The role of natural catastrophes, including flooding,
with respect to population dynamics is not known; however, it is
likely that a negative correlation between flood conditions and
Microtus abundance exists (09).
It is unknown what role, if any, flood waters may play in
transporting Amargosa voles from inhabited to uninhabited areas, and
Life History - 2 (DRAFT) - Life History
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

in the subsequent reestablishment of subpopulations. It is
possible, however, that such events are important (06).

SPECIES INTERRELATIONSHIPS:
It has been suggested that the introduced house mouse (Mus
musculus) competes with Microtus californicus (26,27,28). The
potential role of competition and its impacts on M. c. scirpensis is
purely speculative, but there is some evidence suggesting that
competition may limit numbers of M. c. scirpensis. Gould and Bleich
(10) noted large numbers of house mice in habitat apparently suitable
for Amargosa voles, but failed to capture any of the latter species.
Other investigators did, however, capture M. c. scirpensis and
M. musculus in same areas (09).
Competition studies have investigated the potential for
interactions between Microtus californicus and Reithrodontomys
megalotis (Western harvest mouse) (32). While it has been shown (32)
that Microtus does negatively affect Western harvest mice, the
reciprocal negative effect is probably very small or absent. Hence,
the term "amensalism" would more accurately describe the relationship
between these species (33).

OTHER LIFE HISTORY DESCRIPTORS:
Gould and Bleich (10), and Bleich (05) concluded that both snap
traps and live traps could be used to capture M. c. scirpensis.
Although proportionately more voles were captured in Sherman live
traps than in Museum Special Snap Traps, a significant difference in
trap effectiveness could not be demonstrated (05). Both traps were
baited with rolled oats (05,10).
Other investigators (09) captured M. c. californicus in Sherman
live traps using a mixture of different grains as bait. It is clear
from the above that live trapping of this subspecies is possible and
in fact, desirable given the Endangered status of this subspecies (34,
35). Future investigators should utilize live-trapping only.

Life History - 3 (DRAFT) - Management Practices
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

MANAGEMENT PRACTICES

RESULT MANAGEMENT PRACTICE

Beneficial Suppressing wildfire
Beneficial Controlling/Restricting Off-Road Vehicles
Beneficial Restricting/regulating human disturbance of populations
Beneficial Maintaining/Controlling Water Flow
Beneficial Developing/maintaining/protecting wetlands
Beneficial Controlling water levels
Beneficial Controlling/Restricting Mining
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Land Acquisition
Beneficial Controlling/Restricting Pesticide Use
Beneficial Controlling/Restricting Herbicide Use
Beneficial Controlling/Restricting Agricultural Practice
Beneficial Reforestation
Beneficial Controlling/Removing Nonnative Vegetation
Beneficial Transplanting wild animals
Beneficial Controlling/Removing Exotic Vertebrates
Adverse Off Road Vehicles
Existing Off Road Vehicles
Adverse Highway/Railroads
Existing Highway/Railroads
Adverse Soil compaction by heavy equipment in mine areas
Existing Soil compaction by heavy equipment in mine areas
Adverse Draining wetlands, marshes, ponds, lakes
Existing Draining wetlands, marshes, ponds, lakes
Adverse Flooding
Existing Flooding
Adverse Groundwater drawdown
Existing Groundwater drawdown
Adverse Irrigating
Existing Irrigating
Adverse Dredging
Existing Dredging
Adverse Competition
Existing Competition
Adverse Exotic/Feral/Introducted Species
Existing Exotic/Feral/Introducted Species
Adverse Grazing
Existing Grazing
Adverse Vegetation Composition Changes
Existing Vegetation Composition Changes
Adverse Fire
Existing Fire

COMMENTS ON MANAGEMENT PRACTICES -
The Amargosa vole occurs only in a restricted area of the
eastern Mojave Desert, along the Amargosa River in southern Inyo
County, California. The Amargosa River presents the unique situation
of comparatively abundant perennial surface water deep in the Mojave
Management Practices - 1 (DRAFT) - Management Practices
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

Desert, enabling a thriving marsh community to exist in one of the
most arid regions of the United States (05). It is because of the
availability of this, surface water that man has been attracted to the
area, and that mans activities have impacted the habitat of the
Amargosa vole (03).
It is thought that this subspecies no longer occurs at the type
locality because of habitat destruction associated with the past
intentional burning of that area, and its subsequent use as a hog
pasture (02). It is not known to what extent the Amargosa vole
originally was distributed in the vicinity of the type locality, but
it is likely that it's present distribution is less than what it had
been historically. Several types of human activities, including the
removal of marsh vegetation (by fire to open these areas for pasture
development), grazing, groundwater pumping, diversion
of springs and the Amargosa River itself, road repair work, road
construction, and the introduction of exotic animals are all known to
have occurred, or presently are occurring. These activities have been
recognized as potential or real threats to the habitat (03). Wetlands
have been filled, and springs as well as the Amargosa River have been
diverted for construction purposes and for the development of hot
mineral baths, particulary near Tecopa Hot Springs.
Road repair activities occasionally alter marsh habitat, and
grazing currently occurs on lands within the restricted historic range
of the Amargosa vole (06). ORV enthusiasts occasionally use marshy
areas at the southern end of Amargosa Canyon (06), despite an effort
on behalf of the Bureau of Land Management to eliminate such
activities (07,08). Currently, house mice are found in limited areas
known to be occupied by the Amargosa vole (09), but have not been
captured in the majority of sites occupied by that species (05,10).
House mice were found to be extremely abundant in areas which
otherwise appeared to be suitable habitat (site 7, described by
Bleich; 05). The potential role of these exotic animals in limiting
vole numbers is speculative, but worthy of further consideration based
on the findings of other investigators (26,27,28).
Another factor, which probably affects vole numbers and
distribution is the periodic flooding (09) which occurs, most often as
a result of summer thundershowers. In the past, areas which supported
populations of voles (05) have been drastically altered by heavy
flooding, and it is likely that vole populations were eliminated
from them (11). Indeed, trapping after a flood yielded no
captures of voles in one area which previously had been inhabited
(09). Periodic flooding will continue, and can be considered a
natural phenomenon; it is possible that such flooding may be a
factor in recolonization of suitable habitat, by transporting animals
to points downstream. Survivors of such floods could form the
founders of "new" subpopulations (06). However, Allen (38), in
an astute observation, noted "On account of its living in such very
localized swamps...the race (M. c. scirpensis) is in a precarious
state much like that of an animal living on a few small islands where
the environment may become unsuitable through slight changes."
Future threats to the Amargosa vole include the continued
development of private land, despite recommendations that such lands
supporting vole populations be acquired (05,07,08). Additionally,
Management Practices - 2 (DRAFT) - Management Practices
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

geothermal leasing activities must be considered a possible threat,
despite BLM contention that three current leases are not active and
are not expected to become a threat to the critical habitat, and
that four pending lease applications contain stipulations to avoid
disturbance of the habitat (03). Despite the statement that,
"Neither the Critical Habitat zone nor immediately adjacent
surrounding lands are now known to contain geothermal resources" (03),
it is believed that the number of hotsprings in the immediate area
dictates a cautionary approach, and that the potential for geothermal
development cannot be ignored.

UNAPPROVED PLAN:
At present, no recovery plan for the Amargosa vole exists.
Development of a Technical Draft is targeted for fiscal year 1987.

Aspects of recovery are being handled by the Sacramento field
office of the U.S. Fish and Wildlife Service, project biologist Ted
Rado. Areas of proposed concentration for recovery may include:

1. Maintain and enhance Amargosa vole populations:
A. Inventory wetland distribution to establish species range and
habitat preferences.
B. Investigate ecological and behavioral relationships of
Amargosa voles.
(1) Dispersal behavior and new habitat reoccupation rates.
(2) Establish reproductive requirements, characteristics,
and parental care behavior.
(3) Food preferences and relationships to plant and seed
production and reproduction.
(4) Competitive interactions, both interspecific and
intraspecific. (Of main concern is the interrelationship
of Amargosa voles and the exotic Mus musculus (House
mouse). Establish any existence of a detrimental
relationship between these species, and implement an
exotic control program if a negative relationship exists.)

2. Protect, secure, and enhance Amargosa vole habitat:
A. Land acquisition - of areas containing populations of the
Amargosa vole (total known range is around 500 acres).
B. Establishment of protective fencing around "core areas".
This is intended to stabilize those areas (around 50 acres) that
are known centers of Amargosa vole activity. This will also
aid in limiting human access and disturbance.
C. Rehabilitation of habitat;
(1) Maintain habitat at prime level for stability of
population (i.e. maintain wetlands integrity and
hydrology (water flow) of area) (this will require
controlling and/or restricting further development of
irrigation projects) and control of noxious invasive plant
species such as tamarisk.
(2) Maintain past diversity of vegetation (i.e., vegetative
rehabilitation and exotic plant control) to stabilize
Management Practices - 3 (DRAFT) - Management Practices
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

vole habitat. Of concern is the exotic plant Tamarisk
(a native of the Mediterranean) that is detrimental to
vole existence. Salt crystals produced and
discarded by this species produces soil conditions
unsuitable for native vegetation such as; Scirpus spp.,
Carex spp., and Juncus spp.. Invasion by this species
produces a monotypic vegetation unsuitable for the
Amargosa vole.
D. Restrict use of herbicides detrimental to native flora.
E. Restrict use of ORV's (off road vehicles) in and around the
habitat of this subspecies.
F. Restrict any possible geothermal development detrimental to the
species.
G. Restrict use of pesticides detrimental to the Amargosa vole.
H. Implement a fire control management plan.

3. Translocate wild Amargosa voles to selected habitats. At present,
Amargosa Canyon is under consideration as a possible relocation
site.

4. Foster interest in and support for, preservation of the Amargosa
vole and its ecosystem.

5. Enforce laws and regulations protecting the Amargosa vole and its
habitat.

Management Practices - 4 (DRAFT) - References
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

References

***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****

01 Bailey, V. 1900. Revision of American voles of the genus
Microtus. N. Am. Fauna, 17:1-88.
02 Kellogg, R. 1918. A revision of the Microtus californicus group
of meadow mice. Univ. Calf. Publ. Zool. 21:1-42.
03 U.S. Fish and Wildlife Service. 1984. Endangered and threatened
wildlife and plants; determination of endangered status and
critical habitat for the Amargosa vole. Fed. Reg. 49:45160-45164.
04 Bleich, V.C. 1979. Microtus californicus scirpensis not extinct.
J. Mammal. 60:851-852.
05 Bleich, V.C. 1980. Amargosa vole study. Calif. Dept. of Fish and
Game, Nongame Wildl. Invest. Final Rept., W-54-R-10. 8 pp.
06 Bleich, V.C. [n.d.] Unpubl. observ. P.O. Box 1573, Bishop, CA
07 Bureau of Land Management. 1983. Management plan for:
Grimshaw Lake Natural Area. Barstow Res. Area, Calf. Desert Dist.,
BLM, Barstow, CA. 42 pp.
08 Bureau of Land Management. 1983. Management plan for:
Amargosa Canyon Natural Area. Barstow Res. Area, Calf. Desert
Dist., BLM, Barstow, CA. 56 pp.
09 Rado, T. and P. Rowlands. 1984. Unpubl. admin. rept. A small
mammal survey and plant inventory of wetland habitas in Amargosa
Canyon and Grimshaw Lake areas of critical environmental concern.
USDI BLM, Barstow Res. Area. 12 pp + appendices.
10 Gould, G.I. and V.C. Bleich. 1977. Amargosa vole study. Calif.
Dept. of Fish and Game, Nongame Wildl. Invest. Prog. Rept.,
W-54-R-9. 4 pp.
11 Bleich, V.C. [n.d.] Unpubl. data. P.O. Box 1573, Bishop, CA
12 Bradley, W.G. 1970. The vegetation of Saratoga Springs, Death
Valley National Monument, California. Natur. 15:111-129.
13 Bradley, W.G. and J.E. Deacon. 1970. The ecology of small mammals
at Saratoga Springs, Death Valley National Monument, California.
J. AZ. Acad. Sci. 6:206-215.
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References - 1 (DRAFT) - References
Species VOLE, AMARGOSA
Species Id ESIS051010
Date 14 MAR 96

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References - 3