(DRAFT) - Taxonomy
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
TAXONOMY
NAME - FOX, KIT, SAN JOAQUIN
OTHER COMMON NAMES - FOX, KIT, SAN JOAQUIN; FOX and KIT
ELEMENT CODE -
CATEGORY - Mammals
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - MAMMALIA,
ORDER AND SUBORDER - CARNIVORA,
FAMILY AND SUBFAMILY - CANIDAE,
GENUS AND SUBGENUS - VULPES,
SPECIES AND SSP - MACROTIS, MUTICA
SCIENTIFIC NAME - VULPES MACROTIS MUTICA
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
San Joaquin Kit Fox
Vulpes macrotis mutica Merriam, 1888
KINGDOM: Animal GROUP: Mammal
PHYLUM: Chordata CLASS: Mammalia
ORDER: Carnivora FAMILY: Canidae
The kit fox (Vulpes macrotis) is the smallest of the North
American foxes, being about 25 percent smaller than the red fox
(Vulpes vulpes). Kit foxes lack the band of coarse, black hairs
which run down the tail of the gray fox (Urocyon cinereoargenteus).
The kit fox has comparatively large ears that are greater than 75 mm
from notch to tip in adults (less than 75 mm in the swift fox
(Vulpes velox), with dense, stiff, white hairs that almost cover the
auricle opening) (01,05,06).
The San Joaquin kit fox is the largest subspecies of Vulpes
macrotis, the skull being larger in almost all dimensions and the
occipital crest more pronounced in adults. The body is slender;
adults being about 50.8 cm (20 in.) long and 22.86-30.48 cm (9-12 in.)
tall at the shoulder. The tail is about 12 inches long, bushy,
cylindrical in shape, and tapering toward the tip. The average weight
is about 4.9 pounds, with males being larger (average 5.0 pounds) than
Taxonomy - 1 (DRAFT) - Taxonomy
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
females (4.6 pounds). The color is generally darker than Vulpes
macrotis macrotis. In summer San Joaquin kit fox coloration is light
buff gray dorsally and white ventrally. Winter pelage is
grizzled-gray dorsally, rusty to buffy-yellow laterally and white
ventrally. The tail is light buff to buffy-gray with a conspicuous
black tip. Legs and feet are long and slender and whitish in color.
The soles of the feet are well haired (05,06,07,08).
The kit fox was originally described by Merriam in 1888 using the
name Vulpes macrotis. The San Joaquin kit fox was named Vulpes
muticus by Merriam in 1902. Grinnell in 1913 considered it a
subspecies and used the name Vulpes macrotis muticus and later (1933)
changed the subspecies name to mutica. Lechleitner and others in
1969, and later, treated it as a subspecies of the swift fox using
the name Vulpes velox macrotis. Hall and Kelson (1959) and others
noted the similarity between the two forms but chose the conservative
course of full species status for each. Rohwer and Kilgore (1973)
examined species from the interface zone between the two, favoring
seperate status for each. Thornton and Creel (1975) confirmed this
conclusion based on differences in several external characteristics
and blood serum and hemoglobin protein electrophoresis, supporting the
name of Vulpes macrotis for the kit fox. Waithman and Roest in 1977
clearly demonstrated that the San Joaquin kit fox is separable from
other kit foxes based on size, as noted by Grinnel in 1937, cranial
features, geography, and habitat type. Their conclusion is that the
San Joaquin kit fox is a valid subspecies deserving the name Vulpes
macrotis mutica (01,05).
The type locality of the San Joaquin kit fox is near Tracy, San
Joaquin County, California, as noted by Merriam in 1902. Specimens
located at the U.S. National Museum of Natural History included
7 specimens from Tracy, San Joaquin County; 3 specimens from Alila and
1 specimen from Goshen, Tulare County; 1 specimen from Bakersfield,
Kern County; and 3 specimens from Coalinga, Fresno County. At the
University of California, Museum of Vertebrate Zoology, Berkeley,
there are specimens from (location followed by number of specimens
collected from each site): Shandon, San Luis Obispo County (1);
Blackwells Corner (1), Keck's Corner (7), and Rose Station (1), Kern
County; and Panoche Creek (3), Mercy Hot Spring (2) and west of
Firebaugh (9), Fresno County. At the California State Polytechnic
University, San Luis Obispo, there are two specimens from Buttonwillow
and the Snedden Ranch, Kern County. California State University at
Fresno also has a collection of San Joaquin kit fox. Photographs or
drawings are available from the California Department of Fish and
Game, Sacramento, California and several other sources in the area
(05).
Taxonomy - 2 (DRAFT) - Status
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
STATUS
Coded Status
E: Federal Endangered
Game (Consumptive Recreational)
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The San Joaquin kit fox (Vulpes macrotis mutica) 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.
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 foreign law; 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.
DOD -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public land under their control. Also responsible for
management/recovery on Department of Defense lands.
USFS -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public lands under their control. Also responsible
for management/recovery on Forest Service lands. The
Forest Service is responsible for integrating
management, protection, and conservation of Federally
Status - 1 (DRAFT) - Status
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
listed species into the Forest Planning process
(36 CFR 219.19 and 219.20).
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
conservation of the species.
STATE STATUSES AND LAWS:
STATE: California
DESIGNATED STATUS: Threatened
ADMINISTRATIVE AGENCY: Calif. Dept. of Fish and Game
STATE STATUTE: Endangered Species Act; Fish and Game Code,
Chapter 1.5, Article 1, Sect. 2050.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
The San Joaquin kit fox is listed by the United States in the
Convention on Nature Protection and Wildlife Preservation in the
Western Hemisphere Annex (1970).
ECONOMIC STATUSES:
The San Joaquin kit fox has a former consumptive recreational
value as a hunted species (i.e., "varmint hunting").
67/03/11:32 FR 04001/ - Listed as Endangered, Preact 1
70/10/13:35 FR 16047/16048 - Preact 7, Relisting
79/05/21:44 FR 29566/29577 - Notice of Status Review
85/07/22:50 FR 29901/29909 - Notice of Review
87/07/07:52 FR 25522/ - Notice of 5 year review completion
Status - 2 HABITAT ASSOCIATIONS
HABITAT - TERRESTRIAL
TERRESTRIAL
INLAND AQUATIC
LAND USE -
Industrial
Transportation, communications, and Util
Cropland and Pasture
Orchards, Groves, Vineyards, Nurseries,
Herbaceous Rangeland
Shrub and Brush Rangeland
Mixed Rangeland
Streams and Canals
Nonforested Wetland
Dry Salt Flats
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Palustrine
Riverine, intermittent SB2
Riverine, intermittent SB1
COMMENTS ON HABITAT ASSOCIATIONS -
Prime habitat for the San Joaquin kit fox is the arid and
semi-arid plains of the San Joaquin Valley floor, consisting of alkali
sink, saltbush scrub and grassland plant communities. Other important
types include foothill saltbush scrub, grasslands, intermittent
streambanks and washes. Of lesser importance are lowland sinks
subject to flooding and foothill woodlands at higher elevations (06).
The alkali sink community consists of poorly drained barren playas
and hummocks with salt-tolerant vegetation such as saltgrass
(Distichilis spicata), seepweed (Suaeda fruticosa), iodine bush
(Allenrolfea occidentalis) and a variety of annual flowering plants
and grasses. It is doubtful that the original range of the San
Joaquin kit fox included these wetland areas due to the limited
sites that contained well drained soils (most of the habitat of this
type is saturated and has periodic flooding) for den sites. Saltbush
scrub communities occur on better drained soils and are dominated by
desert saltbush (Atriplex polycarpa), interspersed with a variety of
annual grasses and some annual flowering plants and other perennial
shrubs. While alkali sink areas have been extensively converted
to agriculture, the saltbush scrub areas are subject to even greater
conversion (01,06,07,08,09). The high loss of optimal habitat to
development has forced the kit fox into areas of secondary habitat
(often this means areas of wetland types - alkali sinks and tule
marshes).
Foothills and hillside scrub, grassland and woodland habitats are
generally on shallower soils making burrow excavation more difficult,
thus less adapted to kit fox occupation. The foothill oak woodlands
are sometimes occupied by kit foxes but they are better suited for
the gray fox (Urocyon cinereoargenteus) (06,08,09).
Intermittent streamside habitat and arid washes may be occupied
by kit fox. Streamside vegetation habitat may be dominated by
mesquite (Prosopis glandulosa), cottonwood (Populus fremontia), willow
(Salix sp.) and quail bush (Atriplex lentiformis) (06,08). These
areas are especially suitable if mixed with or adjacent to arid shrub
Habitat Associations - 1 or grassland habitats. Washes are used for foraging and sometimes
denning in banks just above the wash floor (09,16). Valley lowlands
of tall grass associations are of reduced value to kit foxes because
of saturated soils, periodic flooding and unsuitability for prey base
animals. Only isolated, well drained soils suitable for den
excavation in these habitats may be occupied by kit foxes (06).
Habitat requirements include loose textured soils for den
excavation, an adequate prey base, and an arid climate. Soils
of sandy clay and sandy loam, stone-free for about 3 to 4.5 feet of
depth, are preferred. These are usually found in deep alluvial fans
and floodplains. Adverse soil conditions include shallow soils over,
high water tables, saturated soils, and impenetrable hardpan or
caliche layers (06,08,09,16).
Climate typical of kit fox habitat consists of hot, dry summers
of 38-118 degrees Farenheit (F) and cool, wet winters of 13-89 deg. F.
Areas are subject to 1-12 inches of precipitation, usually between
November and April, when lowlands are subject to seasonal flooding
(06,08,09). These conditions are normally found at elevations up to
about 3000 feet. Level areas are preferred, although kit fox may
inhabit slopes up to 40 degrees. Natal or pupping dens are almost
exclusively dug in areas of low relief, about 6 degrees of slope
(06,16).
San Joaquin kit foxes are tolerant of human activities that do
not reduce denning sites. Light industrial development, including oil
fields, primitive or limited road development, and limited urban
development, allow for continued area use by kit fox. Kit foxes can
be found close to urban areas and are known to inhabit portions of the
California Aqueduct right-of-way. Bridges, culverts and piles of pipe
or other materials may be used for cover. Kit foxes may be found in
association with agricultural areas such as pasture, hay, cotton, and
sugar beet fields, fruit and nut orchards, and vineyards. The
occurrence of kit fox in developed areas seems to be either quite
marginal or merely incidental and dependant on the presence of an
adequate prey base and nearby suitable denning areas (06,07,08,16).
Habitat Associations - 2 (DRAFT) - Food Habits
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
LIFESTAGE FOOD FOOD PART
General Poaceae
General Forb Leaves/Stems
General Reptilia
General Aves
General Carrion
General Arthropods
General Mammalia
Food Habits - 1 (DRAFT) - Environment Associations
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
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 Terrestrial Features: Depressions
G Terrestrial Features: Burrows
G
G
Environment Associations - 1 (DRAFT) - Life History
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
LIFE HISTORY
FOOD HABITS:
San Joaquin kit fox are primarily carnivorous; however, they also
consume invertebrates and vegetation. Pups apparently nurse for one
to two months. Following weaning they are fed primarily kangaroo
rats (Dipodomys sp.) by their parents until they are about three or
four months old. An adult pair will feed about 98 pounds of meat to
five pups in two months. Sub-adults will consume about three ounces
of meat per day and adults consume about twice that (06,07,08,09).
They apparently are opportunistic feeders, although some investigators
believe kangaroo rats are a principal prey item. Kangaroo rat remains
can be found in kit fox scats year-round in the San Joaquin Valley,
while lagomorph remains occur mostly in spring and summer (09). In
agricultural areas, desert cottontail rabbits (Sylvilagus auduboni)
constitute the bulk of the diet (08). It is believed that kit foxes
obtain moisture from their prey. However, a mostly protein diet would
create a water deficiency. The explanation of their water maintenance
is not known (06,09).
Primary diet constituents based on scat analysis and remains
found near burrows is as follows:
kangaroo rats Dipodomys ingens, D. nitratoides,
D. heermanni
cottontail rabbit Sylvilagus auduboni
black-tailed hares Lepus californicus
California ground Spemophilus beecheyi
squirrel
Also occuring frequently in scats are insects, and vegetation seeds
and stems, including:
scorpions Scorpionidae
Jerusalem crickets Stenopelmatus longispinus
ants Formicidae
grasshoppers Oedaleonotus enigma
grasses Bromus sp.
filaree Erodium cicutarium
Incidentally consumed are other small mammals including:
pocket mice Perognathus inornatus, P. flauus
deer mice Peromyscus maniculatus
harvest mice Reithrodontomys megalotis
San Joaquin antelope Ammospermophilus nelsoni
squirrel
gophers Thomomys bottae;
other insects (Insecta) and spiders (Arachnida); seeds and stems of
other grasses and annual flowering plants; birds, including western
meadowlark (Sturnella neglecta) and California quail (Lophortyx
californicus); and lizards (06,07,08,09,17). They are known to eat
Life History - 1 (DRAFT) - Life History
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
old, decaying meat and carrion from road-kills caused by motor
vehicles (06,07,09).
HOME RANGE/TERRITORY:
San Joaquin kit foxes appear to have no foraging territorial
behavior by individuals nor families. They do have family denning
areas with home ranges of varying sizes depending on prey base
abundance. Home ranges vary from about one to two square miles.
Knapp, in a 1977 study, found minimum ranges of 120 acres to 1,851
acres in size. There may be from 1-6 kit foxes per square mile,
indicating that a great deal of overlapping in home ranges can occur.
Adults are usually solitary from June until October. From October to
June they are paired and establish natal dens. The pups remain close
to natal dens until the family groups seperate in summer. There is
movement from home ranges for breeding and population dispersal
(06,08,09,10).
PERIODICITY:
San Joaquin kit fox are generally nocturnal, although some
diurnal activity does occur, especially when caring for young. Pups
can often be seen in playful activity during the daytime near the
entrances to their natal den. This is most common between two and
six o'clock in the afternoon during the spring season. Otherwise,
adults may occasionally appear above ground during the daytime. This
activity is mostly in the summer and fall. Normal activities begin at
sunset and continue off and on throughout the night. Kit foxes do
not hibernate during the winter (09).
MIGRATION PATTERNS:
San Joaquin kit foxes have a very limited area of travel. They
are not known to be migratory, except for short movements during
population dispersal and seeking of a mate for breeding purposes.
Unlike the desert kit fox which has been known to travel 20 miles,
this subspecies is believed to move less than 1.25 miles on the
average. Knapp (1977) found individual home ranges with maxium
distances between farthest points traveled of 0.5 miles to 3.5 miles.
Pups will generally leave their natal den area to find a place to
inhabit. An adult may move from the denning area to pair with a new
mate in another area (06,08,09,15).
COVER/SHELTER REQUIREMENTS:
Dens provide the only substantial shelter for the San Joaquin kit
fox. Artifical dens such as culverts, well casings, abandoned
pipelines, and man-made burrows are used by kit foxes. Larger, natal
(brood, pupping) dens are occupied by single family groups during the
reproduction period of October or November through May or June. Other
smaller, individual dens are used by solitary kit foxes during the
balance of the year (06,08,09,16).
Usually kit foxes excavate their dens in loose textured soil at
elevations between 350 and 2,950 feet in areas of low-to-moderate
relief, averaging about 20 degrees of slope. Natal dens are found
on flatter terrain, averaging about 6 degrees of slope. Large dens
are often found in association with abandoned ground squirrel mounds.
Life History - 2 (DRAFT) - Life History
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
In hardpan soils, kit foxes may use abandoned badger burrows which
have already penetrated the harder substrate. Dens are typically not
found in shallow soils over bedrock nor areas of shallow water table
(06,16).
Den entrances are about 10-18 inches deep and 12-36 inches
wide. Natal dens have up to 18 entrances, averaging six, while
solitary dens have three or less. Most commonly, solitary dens are
comprised of two entrances. Entrance tunnels are quite small,
measuring 8 to 11 inches high and 4 to 6 inches wide. Openings of
this size would prohibit entry of predatory coyotes and badgers.
Inside tunnel diameters are further reduced, being 5 to 6 inches high
and 6 to 8 inches wide. Enlarged areas inside dens are up to 10
inches high. Den passages are constructed to depths of 50 or more
inches below the ground surface and may extend 15 feet horizontally
from entrances. Active dens can be identified by fresh dirt about the
entrance, along with scats and prey remains. Nearby grass may also be
matted from trampling. Vacant kit fox dens may become occupied by
burrowing owls (Athene cunicularia) or other animals.
Kit fox dens are not shared, but occupied by individual foxes or
single family groups. Exceptions to this are rare. A single family
may move from one den to another several times during the time pups
are being raised. This may be for utilizing a new prey base or to
escape ectoparasite populations.
An individual kit fox may use from 3 to 24 different dens. As a
result, most dens are vacant at any one time. One family, an adult
with a different mate each year, and two of their offspring, occupied
41 different dens during a fifteen-month period. Seven pairs occupied
71 different dens during that same period. Converselt in study areas
being subjected to conversion to agriculture, there were three dens
per fox (06,08,09).
Density of kit fox dens varies from 11 to 29 per square mile.
Of this, there are 0.29 to 1.78 active dens per square mile, averaging
0.81. On the San Joaquin Valley floor kit fox habitat, there is an
average of 5.8 dens per square mile, of which 1.0 is active. In
foothill habitats the average is 3.5 dens per square mile with 0.6
active (09).
REPRODUCTIVE SITE REQUIREMENTS:
San Joaquin kit fox mated pairs occupy large dens with multiple
entrances, sometimes very complex networks of tunnels, and enlarged
maternity chambers. Natal dens are used from year to year and may be
altered or extended each year. Natal dens may represent ancestrial
breeding or rearing sites that are important to survival of the
species. Because of the denning territoriality of the species, active
natal dens of different mated pairs are usually separated by 1.2 - 2.0
miles. Thus, natal den density becomes a major limiting factor for
a kit fox population (06,09).
Natal dens are found on terrain of limited slope, averaging about
6 degrees. About 50 percent are found on flat terrain. Active natal
dens are more likely to have scats, prey remains, and extensive matted
vegetation around their entrances. Tunnel size varies from 5-6 inches
high and 6-8 inches wide. Maternity chambers may be as large as 24
inches wide and 12 inches high. Tunnels and maternity chambers may
Life History - 3 (DRAFT) - Life History
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
extend as far as 50 inches below the ground surface. Because a
family may move from one den to another during the reproductive
period, there are usually several natal dens within a denning
territory. Den changes may be due to depleted prey base or
ectoparasite infestations (06,09,16).
REPRODUCTIVE CHARACTERISTICS:
Female San Joaquin kit foxes return to natal dens in September or
October and begin to clean and enlarge them. The males join the
females in October and November. Breeding begins in December and
extends into January or February. Young are born in February or March
following a 49-55 day gestation period. The females have only one
litter 3-5 pups per year, averaging 3.4. Pups do not emerge
from the den until they are about one month old. They are probably
weaned at about that time. Individual foxes do not breed successfully
their first year, maturing at 22 months of age or later. They are
basically not monogamous even though the prior mates may coinhabits an
area. Occasionally there may be a pair that mates year after year.
Males rarely fight over a female and may breed with several females
(06,09).
PARENTAL CARE:
The female nurses the pups for about 1 to 2 months. Both parents
forage for food for the young and bring captured prey animals to the
den for the pups until they are about 4-5 months old. At that time
the pups begin to forage for themselves, family bonds begin to
dissolve, and individuals disperse. During the period when adults are
providing food for the young, the male may occupy the same den with
the female or will use another den nearby. Sometimes after a family
separates, a pup may stay with an adult or another pup through the
summer (06,09).
POPULATION BIOLOGY:
San Joaquin kit fox abundance depends directly in the number
of natal den sites available and the abundance of prey animals.
Territoriality of denning pairs limits the number of natal dens per
unit area. Home range area for individual foxes depends on adequate
prey base and can overlap extensively with other foxes. Early
estimates indicated densities of 1.0 adult kit fox per square mile.
In 1970, it was estimated at 0.36 to 1.0 per square mile. A more
refined study in 1975 based on density of active dens indicated
between 1.0 and 1.4 kit fox per square mile. Valley floor habitats
generally have higher kit fox densities than foothill areas. An
analysis of available data in 1983 indicated that there were about
7,000 kit foxes occupying about 5,000 square miles of habitat in 1975.
There has subsequently been more San Joaquin Valley floor habitat lost
to agricultural and other developments. This amounted to about 60
square miles annually during the period 1976 to 1979 (06,07,11,14).
Estimates of the size of the range occupied by the kit fox have
changed over the years. It has apparently been severely reduced from
the original range within the San Joaquin Valley and Carrizo Plain.
Subsequent studies in 1970 and 1975, however, indicated exansion of
kit fox range into portions of the southern San Joaquin Valley and
Life History - 4 (DRAFT) - Life History
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
Coast Range foothills and additional intermountain plains. It is not
known if this condition reflected recent colonization into these areas
or if earlier studies were not thorough enough to detect kit fox
locally (06).
Population densities are typically relatively stable, where
individuals leaving an area are replaced by others moving in. Young
individuals are only able to establish themselves if an adult moves
out, dies or is killed. Spotlighting surveys of selected portions of
the range indicated an overall increase between 1970 and 1975 with a
slump in 1972.
Starvation will eliminate surplus kit foxes in the absence of
other mortality factors. They can live to at least seven years of
age; however, longevity averages between 1.8 and 2.2 years. In that
time a pair of foxes can produce two litters of 3 to 5 pups (06,09).
Changes in prey base abundance can influence kit fox densities
and could reduce their populations if widespread or long-term trends
of prey base reduction took place. Loss of habitat remains the
greatest threat to this taxon.
SPECIES INTERRELATIONSHIPS:
San Joaquin kit fox are preyed upon by badgers (Taxidea taxus),
coyote (Canis latrans), and probably golden eagles (Aquila chrysaetos)
(06,09). Prey species for kit fox are given above under "Food
Habits".
Parasites of kit fox include sticktight fleas (Echionorhoya
gallinacea) and other fleas, ticks, lice, and possibly roundworms and
tapeworms.
Other animals common to kit fox habitat include: skunks
(Spilogale putorius, Mephitis mephitis), burrowing owls (Athene
cunicularius), lesser nighthawks (Chordeiles acutipennis), western
kingbirds (Tyrannus verticalis) and many other bird species,
blunt-nosed leopard lizards (Gambelia silus), western whiptail lizards
(Cnemidophorus tigris), side-blotched lizard (Uta stansburiana),
coast horned lizards (Phrynosoma coronatum), coach whip snakes
(Masticophis flagellum), gopher snakes (Pituophis melanoleucus),
western rattlesnakes (Crotalus viridis) and many insects and spiders
(01,06,07,08,09,17,18).
OTHER LIFE HISTORY DESCRIPTORS:
None.
Life History - 5 (DRAFT) - Management Practices
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Adverse
Adverse Flooding
Adverse Food Supply Reduction
Adverse Gas/Oil Development
Adverse Grazing
Adverse Harassment/Vandalism/Indiscriminate Killing
Adverse Soil compaction by heavy equipment in mine areas
Adverse Highway/Railroads
Adverse Incidental Capturing/Killing
Adverse Off Road Vehicles
Adverse Oil Spills
Adverse Applying pesticides
Adverse Poaching
Adverse Reservoirs
Adverse Rural Residential/Industrial Areas
Adverse Sport Hunting/Fishing
Adverse Vegetation Composition Changes
Adverse Predator control
Adverse Irrigating
Beneficial Controlling/Restricting Agricultural Practice
Beneficial Controlling/Restricting Off-Road Vehicles
Beneficial Reforestation
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Controlling/Restricting Road Maintainance Actions
Beneficial Land Acquisition
Beneficial Restricting/regulating human use of habitats
Beneficial Transplanting wild animals
Existing
Existing Flooding
Existing Food Supply Reduction
Existing Gas/Oil Development
Existing Grazing
Existing Harassment/Vandalism/Indiscriminate Killing
Existing Soil compaction by heavy equipment in mine areas
Existing Highway/Railroads
Existing Incidental Capturing/Killing
Existing Off Road Vehicles
Existing Oil Spills
Existing Applying pesticides
Existing Poaching
Existing Reservoirs
Existing Rural Residential/Industrial Areas
Existing Sport Hunting/Fishing
Existing Vegetation Composition Changes
Existing Predator control
Existing Irrigating
Management Practices - 1 (DRAFT) - Management Practices
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
COMMENTS ON MANAGEMENT PRACTICES -
The primary threat to the San Joaquin kit fox is the loss of
habitat in the San Joaquin Valley due to agricultural development.
Conversion of native lands to agriculture has been greatly accelerated
by the development of the Federal Central Valley Project and the
California Water Plan, along with numerous other local water
developments. Off-site reservoirs and conveyance facilities have
provided abundant inexpensive water for irrigation. Diversions,
canals, and water storage ponding (flooding) within the kit fox range
have contributed to habitat loss (07,08,09). Agricultural development
related losses include: direct mortality from burial in dens by heavy
equipment operation; displacement of kit foxes from their home ranges;
a displaced or reduced prey base requiring increased foraging area for
kit foxes (this increase mortality from road-kills becuse of an
increase in roads and traffic); and reduced kit fox reproduction
resulting from destroyed denning areas (08). Other, less extensive
habitat losses in the San Joaquin Valley area result from
urbanization, industrial development (particularly oilfields), and
construction projects such as the California Aqueduct and Interstate
Highway 5 (01,07,08,09,10,11,14). Each of these activities requires
the operation of heavy equipment and alters the native landforms and
vegetation. The results are the same as with agricultural
development. In addition, oilfield operations can produce oil spills
which can kill or injure foxes and reduce their prey food base.
Conversion of wildlands was largely responsible for the 20-43
percent reduction in kit fox population estimates during the 50 years
prior to 1975 (07). An estimated 34 percent reduction in native
habitat within the San Joaquin kit fox range took place between 1959
and 1969 (10). By 1979, only 6.7 percent remained of the original
7,500,000 acres of undeveloped wildlands in the San Joaquin Valley
south of Stanislaus County. At the current rate of habitat loss, it
is estimated that there will be none left in that area by 1996 (14).
Other threats include shooting, trapping, road-kills by
motor vehicles, off-road vehicle activity, pesticides, (for animal
damage control activities) and domestic livestock grazing (07,09,12,
13).
Illegal shooting of kit foxes was considered a significant
problem and resulted in the closure of certain portions of its
range to night hunting in 1972. Some illegal shooting continues,
however. Along with illegal shooting, direct mortality to kit foxes
occurred during past fur-trapping activities. In 1972, trapping was
made illegal in portions of the kit fox range. In 1981, the closure
was modified to allow trapping of legal non-game mammals. The extent
to which kit foxes are taken incidentally to this is not known (06,07,
09). Road kills have increased as roads and highways have been
developed and vehicle traffic has increased along existing roads.
Off-road vehicle activity can contribute to habitat damage by
destroying vegetation, compacting soils and accelerating erosion.
Declines in kit fox populations in the Panoche Hills of Fresno County
were linked in part to excessive habitat destruction associated with
off-road vehicles. A study of desert kit fox failed to show impacts
from off-road vehicle activities; however, it was concluded that
denning areas, especially natal and pupping, should be protected from
Management Practices - 2 (DRAFT) - Management Practices
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
off-road vehicle harassment and possible collaps of dens (06,11,15).
This type of activity will continue to effect San Joaquin kit fox
habitats and will probably be intensified locally as sites available
for off-road vehicle recreation are reduced by other land uses.
Concerns about pesticides used in rodent control and their
effects on San Joaquin kit fox have been expressed for many years.
Laboratory studies indicate that kit foxes are very sensitive to
rodent bait containing compound 1080 (sodium monofluoroacetate).
Because kit foxes are known to feed on carrion, they may consume
poisoned animals or feed them to their young. Studies by the U.S.
Environmental Protection Agency, using the desert kit fox (V. m.
arsipis) as a test animal, clearly show a high valnerability to kit
foxes through ingestion of poisoned rodents. Additionally, a study
using radio-collored coyotes showed that animals showing clear
signs of 1080 poisoning died in areas where they could otherwise
never have been found. The duration of time between ingestion of
poisoned food and onset of poisoning symptoms (1-24 hours) provides
ample time for animals to seek shelter underground in dens away from
the 1080 application area (13,19). Agricultural interests maintain
the necessity of applying toxic chemicals for rodent and lagomorph
control (06,07,09,11,12,13).
Grazing of domestic livestock has modified habitat in much of the
kit fox range. The effects of livestock grazing on kit foxes are not
well understood. Grazing may have been responsible for kit fox range
extension into the Salinas and Santa Clara Valleys by modifying the
habitats there. However, it is generally agreed that overgrazing is
detrimental to kit foxes (01,06,07,11,16).
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1985. Revised San Joaquin Kit Fox
Recovery Plan. U.S. Fish and Wildlife Service, Portland, OR. 84 pp.
The ultimate objective of the Recovery Plan is to delist the San
Joaquin kit fox. However, at this time it is not known what
population levels and degree of habitat protection are necessary to
satisfy criteria for delisting. Appropriate research is proposed as a
high priority task to provide this information.
Interim objectives of halting the decline of the San Joaquin kit
fox and then increasing population sizes above 1981 levels, thus
justifying a change in status from Endangered to Threatened are
proposed. To acheive the interim objectives, it is recommended that:
(1) 35,000 acres of San Joaquin kit fox habitat be protected in
Zone 1 (Zone 1 contains the focus of the remaining San Joaquin
kit fox population located in western Kern and eastern San Luis
Obispo Counties. It also contains a large contiguous parcel
of relatively undisturbed but manageable Federal land in the
Elk Hills and Buena Vista naval petroleum reserves, plus
substantial acreage on adjacent BLM land. Heaviest demands on the
remaining land are for petroleum developments and grazing.);
(2) protection of the San Joaquin kit fox and its habitat in Zones 1,
2, and 3 be provided (Zone 2 includes the rest of Kern and San
Luis Obispo Counties as well as Tulare, Kings, Fresno, Monterey
Management Practices - 3 (DRAFT) - Management Practices
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
and a small part of San Benito County that contain the remaining
concentrations of San Joaquin kit fox. Zone 3 contains lower
density populations of San Joaquin kit fox in a scattered
distribution through the northern part of the range in Merced,
Stanislaus, San Joaquin, Contra Costa, Alameda, Santa Clara, and
San Benito Counties, as well as the Cuyama Valley in Santa
Barbara County); and
(3) that the fox be managed to provide at least 1.4 adult San Joaquin
kit fox per square mile on privately-owned and public lands.
The recovery activities necessary to achieve these interim
criteria are to:
1. reduce or reverse the rate at which habitat of the San Joaquin kit
fox is being lost (to agriculture, road construction/maintenance,
development, and related activities in and also to recreational
off-road vehicles) by initiating a program of habitat
management, protection, and acquisition. Strict land zoning may
aid in protection of future habitat loss to development.
2. acquire additional information necessary to understand the
ecological life history requirements of the San Joaquin kit fox
and to determine their compatibility with human activities
such as petroleum field developments, grazing, rodent control
programs, and agricultural development.
3. restore degraded habitats by enhancing natural routes and rates of
reclamation.
4. monitor progress of recovery be determining changes in kit fox
distribution and abundance, habitat losses or gains, rates of
habitat restoration, and acquisition of new information about the
kit fox.
5. investigate the feasibility of reintroductions in portions of the
original range of the San Joaquin kit fox that appear to be
suitable essential habitat, but presently lack evidence of use by
the species.
6. develop strategies for integrating recovery plan objectives into
development and management goals for the southern San Joaquin
Valley.
7. determine criteria necessary to justify delisting the species.
Management Practices - 4 (DRAFT) - References
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 McGrew, J.C. 1979. Vulpes macrotis. Mammalian Species, Am.
Society of Mammal., No. 123. Pp. 1-6.
02 Hall, E.R., and K.R. Kelson. 1959. Mammals of North America.
Ronald Press, New York.
03 Merriam, C.H. 1902. Three new foxes of the kit and desert fox
groups. Proc. of the Biol. Soc., Wash., No. 15. Pp. 73-74.
04 Grinnell, J. 1913. A distributional list of the mammals of
California. Proc. of the Calif. Acad. of Sci. No. 3 Pp. 265-390.
05 Waithman, J.D., and A. Roest. 1977. A taxonomic study of the kit
fox, Vulpes macrotis. Journ. of Mamm., Vol. 58. Pp. 157-164.
06 U.S. Fish and Wildlife Service. 1983. San Joaquin Kit Fox
Recovery Plan. U.S. Fish and Wildl. Serv., Portland, OR. 84 pp.
07 Morrell, Stephen H. 1975. San Joaquin kit fox distribution and
abundance in 1975, Calif. Fish and Game Wildl. Mgmt. Branch Admin.
Rept. No. 75-3. CA Dept. Fish and Game, Sacramento. 27 pp.
08 Knapp, Donna K. 1978. Effects of agricultural development in
Kern County, California, on the San Joaquin kit fox in 1977.
Nongame Wildl. Invest. Fin. Rept. E-1-1, V1.21, CA Dept. Fish and
Game, Sacramento. 48 pp.
09 Morrell, Stephen. 1972. Life history of the San Joaquin kit fox.
Calif. Fish and Game. Vol. 58, no. 3, Pp. 162-174.
10 Laughrin, Lyndal. 1970. San Joaquin kit fox, its distribution and
abundance. Calif. Fish and Game Wildl. Mgmt. Admin. Rept. 70-2.
CA Dept. Fish and Game, Sacramento. 20 pp.
11 Jensen, C.C. 1972. San Joaquin kit fox distribution. U.S. Fish
and Wildl. Serv., Sacramento, CA.
12 Swick, C.D. 1973. Determination of San Joaquin kit fox range in
Contra Costa, Alameda, San Joaquin, and Tulare Counties, California
Department of Fish and Game Special Wildlife Investigations,
Progress Report. CA Dept. Fish and Game, Sacramento. 14 pp.
13 U.S. Environmental Protection Agency. 1983. Sodium
monoflouroacetate (compond 1080). Position document No. 2/3.
Office of Pesticides and Toxic Substances, Wash., D.C.
14 U.S. Fish and Wildlife Service. 1985. Revised Blunt-nosed Leopard
Lizard Recovery Plan. U.S. Fish and Wildl. Serv., Portland, OR.
85 pp.
15 O'Farrell, T.P. and L. Gilbertson. 1979. Ecological life history
of the desert kit fox in the Mojava Desert of Southern California.
Final Rept. Desert Plan Staff, BLM, Riverside, CA.
16 O'Farrell, T.P. and P. McCue. 1981. Inventory of San Joaquin
kit fox on BLM lands in the western San Joaquin Valley. Final
Rept. EGG 1183-2416, EG and G, Santa Barbara Operations, U.S. Dept.
of Energy, Goleta, CA.
17 O'Farrell, T.P. 1980. Elk Hills endangered and threatened species
program, Phase I, Program Summary. Rept. EGG 1183-2403, EG and G,
Santa Barbara Operations, U.S. Dept. of Energy, Goleta, CA. 19 pp.
18 Clark, W.A., S.M. Juarez, and D.L. Chesemore. 1982. Nature
Conservancy small mammal inventory of Paine Wildflower Preserve and
The Voice of America in Kern County, California. Calif. State
References - 1 (DRAFT) - References
Species FOX, KIT, SAN JOAQUIN
Species Id ESIS051008
Date 14 MAR 96
Univ., Fresno. 47 pp.
19 Hegdad, P.L., T.A. Gatz, K.A. Fagerstone, J.F. Glahn, and G.H.
Matschke. 1979. Hazards to wildlife associated with 1080 baiting
for California ground squirrels. Final rept. prepared by the U.S.
Fish and Wildl. Serv. under Interagency Agreement EPA-IAG-D7-0449.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Laughrin, Lyndal. 1970. San Joaquin kit fox, its distribution and
abundance. Calif. Fish and Game Wildl. Mgmt. Admin. Rept. 70-2.
CA Dept. Fish and Game, Sacramento. 20 pp.
02 Jensen, C.C. 1972. San Joaquin kit fox distribution. U.S. Fish
and Wildl. Serv., Sacramento, CA.
03 Swick, C.D. 1973. Determination of San Joaquin kit fox range in
Contra Costa, Alameda, San Joaquin, and Tulare Counties, California
Department of Fish and Game Special Wildlife Investigations,
Progress Report. CA Dept. Fish and Game, Sacramento. 14 pp.
04 Morrell, Stephen. 1972. Life history of the San Joaquin kit fox.
Calif. Fish and Game. Vol. 58, no. 3, pp. 162-174.
05 Waithman, J.D. 1974. San Joaquin kit fox distribution in the
California Counties of Santa Barbara, Kings, Tulare and Kern. U.S.
Fish and Wildl. Serv., Sacramento, CA.
06 Waithman, J.D., and A. Roest. 1977. A taxonomic study of the kit
fox, Vulpes macrotis. Journ. of Mamm. Vol. 58. Pp. 157-164.
07 U.S. Fish and Wildlife Service. 1983. San Joaquin kit fox
recovery plan. U.S. Fish and Wildl. Serv., Portland, OR 84 pp.
08 Morrell, Stephen H. 1975. San Joaquin kit fox distribution and
abundance in 1975, Calif. Fish and Game Wildl. Mgmt. Branch Admin.
Rept. No. 75-3. CA Dept. Fish and Game, Sacramento. 27 pp.
09 Christenson, Daniel P. 1984. Blunt-nosed leopard lizard habitat,
evaluation of changes 1980-1983. Rept. to: U.S. Fish and Wildl.
Serv., Contr. 11310-01687-3, U.S. Fish and Wildl. Serv., Sacramento,
CA. 3 pp.
References - 2