Desert Iguana (Dipsosaurus dorsalis)

Desert Iguana (Dipsosaurus dorsalis)


General Distribution

The desert iguana is widely distributed throughout the Mojave and Colorado deserts below 1000 m (3300 ft) elevation (Stebbins 1954). Its range in California broadly overlaps that of creosote scrub. Desert scrub, wash and succulent shrub habitats are used, as is alkalai scrub. It is found in greatest abundance in sandy creosote flats but can also be found in rocky or hilly areas (Norris 1953, Stebbins 1954).

Habitat Requirements

The desert iguana uses burrows extensively and also climbs into shrubs for shelter from temperature extremes, solar radiation and predators. Mammal burrows are modified or new burrows are constructed by the lizards. Burrows may consist of a shallow, short tube or a more complex arrangement with a central chamber and several exits. The central chamber may measure up to 15 cm in diameter and lie 3-5 cm deep in the soil. When the lizard is present the entrance is usually blocked by sand. This could serve to discourage predators and retard heat gain or loss. These burrows are usually constructed in the hummocks of sand that accumulate around the bases of bushes (usually creosote). Burrows may also serve as nest sites for females. The presence of sand hummocks seems to be important as a construction site for burrows (Norris 1953).

Reproduction

Courtship and copulation occur shortly after emergence in the spring (Norris 1953, Moberly 1961, Mayhew 1971). Egg-laying usually takes place in late May and the young appear in late July to late August. There is considerable variation in these events from year to year and north to south in the range. There is strong evidence that only one clutch of eggs is laid each year (Norris 1953, Mayhew 1971, Grestle and Callard 1972) ranging from 3-8 eggs. Adults reduce surface activity after the appearance of the young; this may reduce competition for scarce food resources. During the period of courtship pairs of lizards (presumably male and female) have been reported foraging together (Norris 1953). This suggests the presence of pair-bonds.

Daily/Seasonal Activity

This species is more heat-tolerant than any other North American reptile. It emerges later in the year and later in the day than other lizards and remains active longer into the hottest part of the day than other lizards. In Palm Springs, it becomes active in late March to mid-April (depending upon the year), later further north (Norris 1953, Stebbins 1954, Moberly 1961, Mayhew 1971). Adults remain active until mid-summer when the young hatch. Young remain active until fall. This species emerges later in the day and remains active later than other species of lizards. Body temperatures of 45° C have been recorded, well above lethal levels for most other species (Norris 1953). Activity consists largely of foraging, moving from one food plant to the next and eating. Most of the time on the surface is spent basking in the sun on hummocks near burrows or in bushes.

Diet and Foraging

These lizards are primarily herbivorous, eating flowers, buds, fruits and leaves of many annuals and perennials, especially creosote. Individuals have been observed to climb up to 2 m (6.6 ft) into a bush to forage. In addition to vegetation, insects, feces (mammal and lizard) and carrion have been reported in their diets (Norris 1953, Stebbins 1954).

Territoriality/Home Range

One study reports male home ranges of .15 ha (.36 ac) and female ranges of .16 ha (.38 ac) (Krekorian 1976). Evidence suggests that this species is territorial during the mating season. During the remainder of the active season, home ranges overlap extensively, and there is little aggressive behavior (Norris 1953, Krekorian 1976).

Predator-Prey Relations

Few reports of predation on this species are available, but it must certainly be preyed upon by Masticophis flagellum and Crotalus cerastes (both lizard-eating snakes), probably by loggerhead shrikes and other avian predators. Young are probably eaten by leopard and collared lizards and mammalian predators (coyote, kit fox, badger, etc.).

Literature Cited

Carpenter, C. C. 1961. Patterns of social behavior in the desert iguana, Dipsosaurus dorsalis. Copeia 1961:396-405.
Grestle, J., and I. Callard. 1972. Reproduction and estrogen-induced vitellogenesis in Dipsosaurus dorsalis. J. Comp. Biochem. Physiol. 42A:791-801.
Krekorian, C. O. 1976. Home-range size and overlap and their relationship to food abundance in the desert iguana, Dipsosaurus dorsalis. Herpetologica 32:405-412.
Mayhew, W. W. 1971. Reproduction in the desert lizard, Dipsosaurus dorsalis. Herpetologica 27:57-77.
Moberly, W. 1961. Hibernation in the desert iguana, Dipsosaurus dorsalis. Physiol. Zool. 36:152-160.
Muth, A. 1977. Eggs and hatchlings of captive Dipsosaurus dorsalis. Copeia 1977:189- 190.
Norris, K. S. 1953. The ecology of the desert iguana Dipsosaurus dorsalis. Ecology 34:263-287.
Pianka, E. R. 1971. Comparative ecology of two lizards. Copeia 1971:129-138.
Stebbins, R. C. 1954. Amphibians and reptiles of western North America. McGraw-Hill, New York. 536pp.

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Field Guide to Reptiles of Southern California Alligator Lizard

Southern Alligator Lizard (Elgaria multicarinata)


General Distribution

Generally common in suitable habitats, the southern alligator lizard is widespread in northern and central California west of the Sierra-Cascade crest and in southern California west of the desert regions. Apparently absent from the extreme northwestern part of the state and from the southern San Joaquin Valley, isolated populations are known from western Inyo Co. and a desert extension of the range occurs along the Mojave River. Populations are also known from most of the Channel Islands. Elevation sea level to 2250 m (7500 ft). Occurs most commonly in valley-foothill habitat types, mixed chaparral, and in open areas of mixed conifer forest.

Habitat Requirements

Cover is provided by surface objects such as rocks, logs, dense vegetation, and human debris. Refuge may also be taken in crevices and rock fissures. Individuals occasionally burrow in loose soil around or under surface objects such as flat rocks. This species sometimes climbs in dense, shrubby vegetation. This species occurs most commonly in open canopy stages of suitable habitats.

Reproduction

Little is known about specific habitat requirements for courtship, mating, and egg-laying in this lizard. Nussbaum et al. (1983) reports that eggs are deposited in “burrows or in stable talus.” Eggs are reported by Shaw (1943) to have been laid in the burrow of a pocket gopher.In southern California, the first clutch of eggs is laid early in June and hatches in about 11 weeks (Goldberg 1972). Two or even three clutches eggs may be laid by females during a single season (Burrage 1965). Clutch size is about 12 with larger females laying more, larger eggs than small females (Goldberg 1972).

Daily/Seasonal Activity

Basically diurnal, this species is active at cooler temperatures than most other lizards with which it coexists. Active southern alligator lizards have been found by Brattstrom (1965) with body temperatures as low as 11° C (52° F). They are active earlier and later in the day than most lizards, sometimes venturing onto warm roads at night. Activity is reduced during the hot periods of summer. In cooler areas a period of winter inactivity occurs but elsewhere individuals may be active all winter long.

Diet and Foraging

Alligator lizards take mostly insects and other arthropods as prey but will take larger food items, especially other lizards (Cunningham 1956). Evidence for their voracious feeding habits is provided by King (1931) who observed a captive adult female consume 20 immature grasshoppers, 11 katydids, 7 shield bugs and stink bugs, and 3 spiders at a single feeding. Cannibalism has been reported.

Territoriality/Home Range

No information is available regarding the nature of the home range. No evidence for the territorial defense of resources has been reported.

Predator-Prey Relations

Racers, rattlesnakes, garter snakes, loggerhead shrikes, red-tailed hawks, and domestic cats have been reported among the predators of alligator lizards. Competition with other lizards for food, space, or othe resources is probably minimized by the unique physiological tolerances of this species, which allow them to be active at different times and to utilize different microhabitats than other lizards. Competition may be further reduced because of the large range of prey size available to alligator lizards.

Literature Cited

Brattstrom, B. H. 1965. Body temperatures of reptiles. Am. Midl. Nat. 73:376-422.
Burrage, B. R. 1965. Notes on the eggs and young of the lizards gerrhonotus multicarinatus webbi and g. m. nanus. Copeia 1965:512.
Cunningham, J. D. 1956. Food habits of the san diego alligator lizard. Herpetologica 12:225-230.
Dawson, W. R., and J. R. Templeton. 1966. Physiological responses to temperature in the alligator lizard, gerrhonotus multicarinatus. Ecology 47:759-765.
Goldberg, S. R. 1972. Reproduction in the southern alligator lizard gerrhonotus multicarinatus. Herpetologica 28:267:273.
King, F. W. 1931. Food habits of alligator lizards. Yosemite Nat. Notes 10:76.
Nussbaum, R. A., E. D. Brodie, Jr., and R. M. Storm. 1983. Amphibians and reptiles of the Pacific Northwest. Univ. Press of Idaho. 332pp.
Shaw, C. E. 1943. Hatching of the eggs of the san diego alligator lizard. Copeia 1943:194.

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Field Guide to Mammals of Southern California Nelson’s Bighorn Sheep

Nelson’s Bighorn Sheep (Ovis canadensis nelsoni)



General Distribution

Populations of Nelson’s bighorn sheep are found in four areas on National Forest System lands in southern California. The San Rafael Peak/Cobblestone Mountain population is a small, reintroduced population that was established in the 1980s. This population inhabits an area in the southern part of the Los Padres National Forest. Nelson’s bighorn sheep in the San Bernardino Mountains are considered to constitute two separate populations: the larger population (San Gorgonio Herd) occurs in the vicinity of Mount San Gorgonio in wilderness; the other population (Cushenbury Herd) occurs on the northern edge of the range in desert-facing canyons (e.g., Furnace, Bousic, Arctic, and Marble Canyons). Finally, the population in the San Gabriel Mountains is concentrated primarily in the Bear Creek drainage; the upper East Fork of the San Gabriel River and Cattle Canyon (both in the Sheep Mountain Wilderness); San Antonio Canyon; Cucamonga Canyon; and the South and Middle Forks of Lytle Creek (Stephenson and Calcarone 1999).

Systematics

The term “desert bighorn sheep” is used to describe those subspecies of bighorn sheep inhabiting dry and relatively barren desert environments. In the past, these subspecies included Nelson’s bighorn sheep (O. c. nelsoni), Mexican bighorn sheep (O. c. mexicana), Peninsular bighorn sheep (O. c. cremnobates), and Weems bighorn sheep (O. c. weemsi) (Manville 1980). However, new genetic evidence and a recent reanalysis of morphometric data resulted in changes in the accepted taxonomy for Nelson’s bighorn sheep and the Peninsular bighorn sheep (U.S. Fish and Wildlife Service 2001). After their analysis, Wehausen and Ramey (1993) placed Peninsular bighorn sheep within the Nelson subspecies.

Habitat Requirements

Desert bighorn sheep inhabit dry, relatively barren, desert mountain ranges throughout North America. Escape terrain is identified as the single most important habitat component for bighorn sheep in these mountains. Escape terrain is defined as steep slopes (80 percent or steeper) with abundant rock outcrops and sparse shrub cover (canopy cover of 30 percent or less). Nelson’s bighorn sheep in the San Gabriel Mountains occur at elevations of 3,000-10,064 feet (914-3,068 meters [i.e., to the summit of Mount San Antonio]). During the winter and spring, Nelson’s bighorn sheep occur primarily in escarpment chaparral in the lower canyons at 3,000-6,000 feet (914-1,829 meters).

Reproduction

The breeding season of Nelson’s bighorn sheep generally begins in November with the rutting season. Following a six month gestation period, ewes give birth to single lambs (occasionally twins) from late April through early July. During the first few weeks after giving birth, ewes remain alone with their lambs in steep terrain until they join a nursery group. Lambs are weaned at 1–7 months, and juveniles remain with the ewes until they reach sexual maturity (U.S. Fish and Wildlife Service 2000b). Rams are believed to be sexually mature at 6 months of age (U.S. Fish and Wildlife Service 2000a). In the San Gabriel Mountains, the duration of the rut was from mid-September to late December with a peak in late October through the first half of November (De Forge 1980). During the height of the rutting period, mature rams seemed to have little fear of humans and made movements up to 2.5 miles to find ewes.

Daily/Seasonal Activity

In general, bighorn sheep feed in the early morning, at midday, and in the evening, lying down and chewing their cud at other times, and bedding down for the evening. Foraging and bedding spots may be used for years (McMahon 1985). Daily foraging and resting cycles also vary depending on forage quality (U.S. Fish and Wildlife Service 2000a). Seasonal activity depends on availability of water, forage, and escape cover. Typically, bighorn sheep congregate near dependable water sources from May through October, when temperatures are highest. This aggregation of individuals also corresponds with breeding activities. Young bighorn sheep learn locations of escape terrain, water sources, and lambing habitat from older individuals in the group (U.S. Fish and Wildlife Service 2000b). Bighorn sheep migrate between winter and summer ranges, generally moving downslope in winter and spending summer in alpine habitats. Water restricts movement of the species during hot summer months (Zeiner and others 1990).

Diet and Foraging

Nelson’s bighorn sheep graze and browse on succulent grasses and forbs. Sedge, grasses, and small alpine forbs constitute the chief food (Ingles 1965). Browse is an important component of the diet for populations in arid habitats (Zeiner and others 1990).

Territoriality/Home Range

Young ewes learn home range boundaries from their mothers and/or older females and demonstrate a high degree of philopatry to these traditional home ranges throughout their lives (Geist 1971). Rams do not exhibit the same site fidelity as ewes and tend to move among ewe groups. Home ranges in one study were found to average 9.8 square miles (25.5 square kilometers) and 7.8 square miles (20.1 square kilometers) for rams and ewes, respectively (U.S. Fish and Wildlife Service 2000a). De Forge (1980) working in the San Gabriel Mountains found ewe home ranges from 1.84 and 3.06 sq. km (.71-1.8 sq. mi.) and a ram home range to be 17.9 sq. km (6.9 sq. mi.).

Predator-Prey Relations

Recently, mountain lion predation has been documented as a threat to some ewe groups in the Peninsular Ranges. Predation by other species such as coyotes and bobcats may also reduce lamb recruitment (U.S. Fish and Wildlife Service 2000a). Holl (2002) and Holl and others (2002) both implicated predation by mountain lions as a primary cause of the huge decline of the San Gabriel Mountain sheep herd.

Literature Cited

Clark, J.L. 1970. The great arch of the wild sheep. Norman, OK: University of Oklahoma Press. De Forge, J.R. 1980. Ecology, behavior, and population dynamics of desert bighorn in the San Gabriel Mountains of California. Pomona, CA: California State Polytechnic University. M.S. thesis. Geist, V. 1966. The evolutionary significance of mountain sheep horns. Evolution 20: 558-566. Geist, V. 1971. Mountain sheep – a study in behavior and evolution. Chicago, IL: University of Chicago Press. Hamilton, K.M. 1983. Effects of people on bighorn sheep in the San Gabriel Mountains, California. Las Vegas: University of Nevada. M.S. thesis. Hansen, C.G. 1967. Bighorn sheep populations of the desert game range. Journal of Wildlife Management 31: 693-706. Holl, S.A.; Bleich, V.C. 1983. San Gabriel mountain sheep: Biological and management considerations. San Bernardino, CA: Unpublished report on file at the San Bernardino National Forest. Holl, S.A.; Torres, S.G.; Bleich, V.C. 2001. Population dynamics of bighorn sheep in the San Gabriel Mountains, 1967-1998. Paper presented at the September 27, 2001 annual meeting of The Wildlife Society in Reno, Nevada. Holl, S.A. 2002. Conservation strategies for bighorn sheep in the San Gabriel mountains, California. Report prepared for the Los Angeles County Fish and Game Commission, Los Angeles, CA. Lawson, B.; Johnson, R. 1982. Mountain sheep. In: Chapman, J.A.; Feldhamer, G.A., eds. Wild mammals of North America. Baltimore, MD: John Hopkins University Press. Ingles, L.G. 1965. Mammals of the Pacific states- California, Oregon, Washington. Stanford, CA: Stanford University Press. Leslie, D.M., Jr.; Douglas, C.L. 1979. Desert bighorn sheep of the River Mountains, Nevada. Journal of Wildlife Management Wildlife Monograph 66. Light, J.T., Jr.; Weaver, R. 1973. Report on bighorn sheep habitat study in the area for which an application was made to expand the Mt. Baldy winter sports facility. San Bernardino, CA: Unpublished report on file at the San Bernardino National Forest. Manville, R.H. 1980. The origin and relationships of American wild sheep. In: Monson, G.; Sumner, L., eds. The desert bighorn: Its life history, ecology, and management. Tucson, AZ: University of Arizona Press; 1-6. McMahon, J.A. 1985. The Audubon Society nature guides: Deserts. New York: Alfred A Knopf. Shackelton, D.M. 1985. Ovis canadensis. No. 230. Mammalian Species. Published by the American Society of Mammalogists. Stephenson, J.R.; Calcarone, G.M. 1999. Southern California mountains and foothills assessment: Habitat and species conservation issues. General Technical Report GTR-PSW-172. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture.. Torres, S.G.; Bleich, V.C.; Wehausen, J.D. 1994. Status of bighorn sheep in California, 1993. Desert Bighorn Council Transactions 38: 17-28 Torres, S.G.; Bleich, V.C.; Wehausen, J.D. 1996. Status of bighorn sheep in California, 1995. Desert Bighorn Council Transactions 40: 27–34. U.S. Fish and Wildlife Service. 2000a. Recovery plan for bighorn sheep in the Peninsular Ranges, California. Portland, OR: U.S. Fish and Wildlife Service. U.S. Fish and Wildlife Service. 2000b. High priority biological opinion on activities related to trails, dispersed recreation, and developed recreation on the peninsular bighorn sheep. U.S. Fish and Wildlife Service. 2001. Final rule to designate critical habitat for the peninsular bighorn sheep distinct population segment. Federal Register. Wehausen, J.D.; Ramey, R.R., II. 1993. A morphometric reevaluation of the peninsular bighorn subspecies. Desert Bighorn Council Transactions 37: 1-10. Zeiner, D.C.; Laudenslayer, W.F., Jr.; Mayer, K.E., eds. 1990. California’s wildlife. Volume I: Mammals. Sacramento, CA: California Statewide Wildlife Habitat Relationships System, California Department of Fish and Game.

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Field Guide to Mammals of Southern California Mule Deer

Mule Deer (Odocoileus hemionus)

General Distribution

Mule deer occur throughout the Los Padres, Angeles, San Bernardino, and Cleveland National Forests in DAU 9 (Central Coast [south]) and DAU 10 (South Coast). The Central Coast (south) DAU comprises approximately 15,600 square miles (40,400 square kilometers) from the San Francisco Bay and Delta south through Ventura County and east to Interstate 5. National Forest System lands in DAU 9 (all of which are on the Los Padres National Forest) account for 18 percent of the total unit area. The South Coast DAU comprises approximately 7,800 square miles (20,200 square kilometers) from Los Angeles County south to the Mexico border and east to Interstate 10. National Forest System lands in DAU 10 account for 34 percent of the total unit area and include the Angeles, San Bernardino, and Cleveland National Forests.

Systematics

Cowan (1956) and Hall (1981) recognized 11 subspecies of mule deer in North America. Two subspecies are known to occur in the Central Coast (south) and South Coast DAUs. California mule deer (O. h. californicus) occurs in the northern portion of the Central Coast (south) DAU, and southern mule deer (O. h. fuliginatus) occurs in the southern portion of the Central Coast (south) DAU and throughout the South Coast DAU. O. h. fuliginatus differs from O. h. californicus in the following distinguishing features: the summer pelage is darker cinnamon, rather than cinnamon-buff; the dorsal area appears darker with many black-tipped hairs; and the dark spots on the sides of the lower lip are restricted and do not meet on mid-ventral lines (Cowan 1933). The coastal areas of the Los Padres also contains the Columbian black-tailed subspecies (O. h. columbianus) which often interbreed with the California subspecies (O. h. californicus) and these animals are typically very small in size compared to the normal California mule deer and have rump marking more typical of black tails (Freel pers. comm.).

Habitat Requirements

Characteristics of habitat used by mule deer differ geographically. In the low-elevation mountain ranges that lack extensive conifer forests (e.g., the Santa Ana Mountains, mountains of San Diego County, and most of the Los Padres National Forest) mule deer reach their highest densities in oak woodlands, riparian areas, and along the margins of meadows and grasslands (Bowyer 1986). They occur in lower densities in open scrub and young chaparral, but tend to avoid dense brushfields. In chaparral habitats, mule deer thrive on early successional vegetation that is prevalent for 1–10 years after a fire (Bowyer 1981). In the low-elevation mountains of San Diego County (e.g., 4,900-foot [1,494-meter] East Mesa in the Cuyamaca Mountains) mule deer primarily occupy meadows, oak woodlands, and low-elevation pine forests (Bowyer 1984, 1986).

Meadows are particularly important fawning habitat. Deer grass (Muhlenbergia ridgens) is used extensively by fawns for cover, and adult deer typically bed down in oak and pine stands (Bowyer 1984, 1986). The availability of free water during summer is a critical habitat requirement for mule deer in arid regions. On the East Mesa in the Cuyamaca Mountains, mule deer are mostly found in areas within 0.6 mile (1 kilometer) of free water. Areas without sources of summer water are usually devoid of fawns (Bowyer 1986). The most common habitat manipulation used to benefit mule deer is prescribed burning, usually in chaparral. Burning creates openings in the brush and temporarily increases the quality of deer forage (Dasmann and Dasmann 1963).

After observing marked increases in deer harvested in San Diego County following the Laguna fire in 1970, Bowyer (1981) developed deer management guidelines that emphasize burning to rejuvenate browse. Bowyer (1986) points out that the proximity of burned areas to other vegetative types preferred by mule deer may be a critical factor in determining the response of deer populations to alterations in old-growth chaparral. Short-lived increases in forage quality in areas with few deer will do little to promote population growth. Thus, chaparral burns will be most effective when they are conducted in areas that adjoin meadow, oak, or pine vegetation types that contain summer water sources (Bowyer 1981).

Reproduction

Mule deer usually reach sexual maturity at 1.5 years (Mackie and others 1982), and most females breed during their second year (Anderson and Wallmo 1984). Breeding records from 23 separate studies indicate that mule deer breed from mid-September to early March. A peak in breeding appears to occur from late November through mid-December. Young are born from late spring to early autumn, and the peak birth period is generally from mid-June to early July. The most common litter size for mule deer is two. However, females in their first and second breeding year will often produce only one young (Anderson and Wallmo 1984).

Daily/Seasonal Activity

Mule deer may be active day or night but are generally crepuscular, with most activity occurring in the early morning and at dusk (Zeiner and others 1990). Miller (1970) found that activity patterns in black-tailed deer (O. h. columbianus) in northern California are influenced by changes or extremes in temperature, precipitation, and relative humidity. Mule deer in the Central Coast (south) DAU are resident deer that do exhibit some upslope/downslope movement with seasonal changes in weather and food resources, but essentially constitute a nonmigratory population. Mule deer inhabiting the high-elevation mountain ranges (i.e., San Bernardino, San Gabriel, and San Jacinto Mountains and Mount Pinos) of the South Coast DAU commonly undertake elevational migrations between summer and winter ranges (Loft and others 1998).

Migratory movements of up to 15 miles have been noted in the San Bernardino Mountains (Loe pers. comm.). Mule deer inhabiting lower-elevation mountain ranges that lack extensive conifer forests (e.g., the Santa Ana Mountains and mountains of San Diego County) and coastal areas do not migrate, but exhibit some upslope/downslope movement with seasonal changes in weather and food resources (Loft and others 1998, Nicholson and others 1997, Vaughn 1954).

Migratory mule deer move upslope in the summer into well-watered habitats on north-facing slopes dominated by pine forest. These habitats also contain openings, meadows, and riparian habitats that the deer utilize. Nonmigratory mule deer spend the summer on lower slopes, primarily in oak woodlands and the limited pine forests that occur in these lower-elevation areas. In winter, mule deer congregate on lower south-facing slopes where they heavily use oak woodlands, as well as chaparral and sagebrush habitats (Nicholson and others 1997).

Diet and Foraging

Mule deer are herbivores and require adequate supplies of highly digestible, succulent forage (Robinette and others 1973). Although mule deer have traditionally been identified as browsers (consuming predominantly woody forage), studies of their diet and stomach structure have induced researchers to reclassify them as intermediate feeders (consuming equal proportions of woody and herbaceous forage) (Anderson and Wallmo 1984). The type of plants eaten by mule deer is highly variable. Kufield and others (1973) reported that a total of 788 species of plants were eaten by Rocky Mountain mule deer (O. h. hemionus). Of these species, 202 were shrubs and trees, 484 were forbs, and 84 were grasses, sedges, or rushes.

Territoriality/Home Range

Migratory mule deer establish distinct summer and winter home ranges and use approximately the same home ranges in consecutive years. Nonmigratory mule deer maintain yearlong home ranges. The size of mule deer home ranges is highly variable and probably dependent on a number of factors including sex, age, body mass, season, race, and habitat. In general, home range size can vary among deer using the same general habitat; males use larger areas than females. Home range size increases as distance between food, cover, and water sources increase (Anderson and Wallmo 1984).

Predator-Prey Relations

Common predators of mule deer include mountain lion, coyote, bobcat, golden eagle, and black bear (Anderson and Wallmo 1984). When a mule deer detects a predator nearby, it attempts to escape by placing obstacles such as boulders, trees, bushes, and steep slopes between itself and the predator (Geist 1981).

Literature Cited

Anderson, A.E.; Wallmo, O.C. 1984. Odocoileus hemionus. Mammalian Species 219: 1-9. Published by the American Society of Mammalogists. Bowyer, R.T. 1981. Management guidelines for improving southern mule deer habitat on the Laguna-Morena demonstration area. USDA Forest Service, 40-9AD6-9-622. Bowyer, R.T. 1984. Sexual segregation in southern mule deer. Journal of Mammalogy 65: 410-417. Bowyer, R.T. 1986. Habitat selection by southern mule deer. California Fish and Game 72: 153-169. Bowyer, R.T.; Bleich, V.C. 1984. Effects of cattle grazing on selected habitats of southern mule deer. California Fish and Game 70: 240-247. Bunnell, F.L.; Harestad, A.S. 1983. Dispersal and dispersion of black-tailed deer: Models and observations. Journal of Mammalogy 64: 201-209. Cowan, I.M. 1933. The mule deer of southern California and northern lower California as a recognizable race. Journal of Mammalogy 14: 326-327. Cowan, I.M. 1956. Life and times of the coast black-tailed deer. In: Tylor, W.P., ed. The deer of North America. Washington, DC: Wildlife Management Institute. Dasmann, R.F.; Dasmann, W.P. 1963. Mule deer in relation to a climatic gradient. Journal of Wildlife Management 27: 196-202. Geist, V. 1981. Behavior: Adaptive strategies in mule deer. In: Wallmo, O.C., ed. Mule and black-tailed deer of North America. Lincoln, NE: University of Nebraska Press.?Hall, E.R. 1981. The mammals of North America. 2d ed. New York: John Wiley & Sons. Kufield, R.C.; Wallmo, O.C.; Feddema, C. 1973. Foods of the Rocky Mountain mule deer. USDA Forest Service. Resident Paper RM-111. Loft, E.R.; Armentrout, D.; Smith, G.; Craig, D.; Chapel, M.; Willoughby, J.; Rountree, C.; Mansfield, T.; Mastrup, S.; Hall, F. 1998. An assessment of mule deer and black-tailed deer habitats and populations in California: With special emphasis on public lands administered by the Bureau of Land Management and the United States Forest Service. Sacramento, CA: California Department of Fish and Game, Wildlife Management Division. Longhurst, W.M.; Leopold, A.S.; Dasmann, R.F. 1952. A survey of California deer herds: Their ranges and management problems. California Department of Fish and Game Bulletin No. 6. Mackie, R.J.; Hamlin, K.L.; Pac, D.F. 1982. Mule deer (Odocoileus hemionus). In: Chapman, J. A.; Feldhamer, G.A., eds. Wild mammals of North America: Biology, management, and economics. Baltimore, MD: The Johns Hopkins University Press. Mackie, R.J.; Pac, D.F.; Jorgensen, H.E. 1978. Population ecology and habitat relationships of mule deer in the Bridger Mountains, Montana. In Montana Deer Studies. Progress Report. Federal Aid in Wildlife Restoration Project, W-120-R-9. Helena, MT: Montana Department of Fish and Game. Miller, F.L. 1970. Distribution patterns of black-tailed deer (Odocoileus hemionus columbianus) in relation to environment. Journal of Mammalogy 51: 248-260. Nicholson, M.C. 1995. Habitat selection by mule deer: Effects of migration and population density. Fairbanks: University of Alaska. Ph.D. dissertation. Nicholson, M.C.; Bowyer, R.T.; Kie, J.G. 1997. Habitat selection and survival of mule deer: Tradeoffs associated with migration. Journal of Mammalogy 78: 483-504. Robinette, W.L. 1966. Mule deer home range and dispersal in Utah. Journal of Wildlife Management 30: 335-349. Robinette, W.L.; Baer, C.H.; Pillmore, R.E.; Knittle, C.E. 1973. Effects of nutritional change on captive mule deer. Journal of Wildlife Management 37: 312-326. Schaefer, R.J. 1999. Biological characteristics of mule deer in California’s San Jacinto mountains. California Fish and Game 85: 1-10. Stephenson, J.R.; Calcarone, G.M. 1999. Southern California mountains and foothills assessment: Habitat and species conservation issues. General Technical Report GTR-PSW-172. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture. Vaughan, T.A. 1954. Mammals of the San Gabriel mountains of California. University of Kansas Museum of Natural History Publication 7: 513-582. Wallmo, O.C. 1981. Mule and black-tailed deer distribution and habitats. In: Wallmo, O.C., ed. Mule and black-tailed deer of North America. Lincoln, NE: University of Nebraska Press. Zeiner, D.C.; Laudenslayer, W.F., Jr.; Meyer, K.E.; White, M., eds. 1990. California’s wildlife. Volumne III: Mammals. California statewide wildlife habitat relationships system. Sacramento, CA: California Department of Fish and Game.

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Field Guide to Mammals of Southern California

California Black Bear (Ursus americanus californicus)

California Black Bear
General Distribution

Black bears are not native to southern California. Their absence from this region is believed to have been a result of competitive exclusion by California grizzly bear (Ursus arctos californicus). California grizzly bear was extirpated in California near the turn of the century, and black bears began appearing in Ventura and Santa Barbara Counties (Grinnell and others 1937). In the early 1930s, the California Department of Fish and Game initiated a translocation (introduction into the San Gabriel and San Bernardino Mountains) of 28 black bears into southern California to supplement the natural range expansion (Stephenson and Calcarone 1999).

Current black bear populations are known from Ventura and Santa Barbara Counties on the Los Padres National forest; the San Gabriel Mountains on the Angeles National Forest; and the San Bernardino and San Jacinto Mountains on the San Bernardino National Forest. Several sightings have more recently been reported from Palomar Mountain, Buckman Springs, and the Agua Tibia Wilderness Area on the Cleveland National Forest (Tremor and Botta 2000).

Systematics

Of the 16 subspecies of black bear (Ursus americanus) recognized by Hall (1981), northwestern black bear (U. a. altifrontalis) and California black bear occur in California. These two subspecies are separated geographically by the crest of the Klamath Mountains (California Department of Fish and Game 1998). California black bear is the only subspecies that occurs on the four southern California national forests.

Habitat Requirements

Black bear occupies a variety of habitats, but populations are densest in montane hardwood, montane chaparral, and mixed-conifer forests with a wide variety of seral stages (California Department of Fish and Game 1998). Vegetative and structurally diverse habitats are important to black bears because they provide a variety of food types. Black bears may also seasonally inhabit annual grasslands and valley foothill hardwood habitats (California Department of Fish and Game 1998). In the southern California mountains, black bears will follow riparian corridors down into low-elevation habitats (Stephenson and Calcarone 1999). Recently burned or logged forest can provide high-density fruit and berry production, whereas unmanaged and mature hardwood forests provide a variety of nuts and acorns (Lariviere 2001). Female black bears require secure, dry den sites for bearing and rearing young. Dens are also used by both sexes during periods of seasonal dormancy in the winter. Den sites have been found in hollowed-out trees, slash piles, root excavations, under large rocks, and occasionally on open ground (California Department of Fish and Game 1998, Lariviere 2001).

Reproduction

Female black bears reach sexual maturity generally between 3 and 5 years of age (Pelton 1982). Black bears breed in June and July and young are born during January or early February. Litter size ranges from one to four cubs and is probably influenced by the physical condition of the mother in early winter (Lariviere 2001). Although black bears are capable of breeding yearly, the frequency of breeding varies from 1 to 4 years (Lariviere 2001) and is strongly correlated with food availability (California Department of Fish and Game 1998).

Daily/Seasonal Activity

Black bears can be active during the day or night. They are typically crepuscular, concentrating most of their activity during the early morning and evening (Tremor and Botta 2000). In areas inhabited by humans, black bears become predominantly nocturnal and secretive (Lariviere 2001). Black bears in southern latitudes are active year-round, whereas bears in northern latitudes tend to undergo a period of seasonal dormancy in the winter (Tremor and Botta 2000). Because southern California generally has a mild climate, seasonal dormancy is less common and black bears are usually active year-round. However, pregnant females are less active and often den in the winter (Tremor and Botta 2000).

Diet and Foraging

Black bears are omnivores and consume a variety of plant and animal material including grasses, berries, nuts, acorns, wood fiber, insects, reptiles, birds, small mammals, and carrion (Tremor and Botta 2000). Seasonal variations exist in the type of foods eaten by black bears. In the spring, black bears consume mostly new vegetative growth and animal carcasses. During summer, their diet consists primarily of herbaceous material and fruits. During autumn, berries and mast (acorns and nuts) comprise the bulk of their diet (Lariviere 2001). The diet of urban California black bears in the San Gabriel Mountains was analyzed by examining bear scat collected from urban areas (Van Stralen 1998). Based on the total content of all scat analyzed, about 57 percent was native plant material (hollyleaf cherry, manzanita, redberry, grasses, and coast live oak); 26 percent was nonnative plant material (figs, peaches, apples, apricots, avocados, and domestic cherries); 14 percent was human garbage (paper, plastic, and metal); and 3 percent was animal matter (fly pupae and bird bones).

Territoriality/Home Range

The home ranges of black bears vary considerably and are determined by sex, age, season, and population density. The size of a home range is also largely dependent on food availability; concentrations of certain food resources can result in temporary range expansions (Pelton 1982). Black bears in northwestern Montana have been known to travel more than 100 miles (160 kilometers) to take advantage of available food supplies (Rogers 1987). Past studies have shown that the home range size of adult males is often 3-8 times larger than the home ranges of adult females. Using radio-telemetry, Van Stralen (1998) determined (with 95 percent confidence) the home range size of three urban males to be 2.9-11.0 square miles (7.4 to 28.4 square kilometers). The single female in this study had a home range of 2.1 square miles (5.4 square kilometers). Previous studies in southern California have reported home range sizes of 3.3, 7.5, and 9.7 square miles (8.6, 19.5, and 25 square kilometers) (Van Stralen 1998). Adult female black bears in northwestern Montana established territories in the summer (Rogers 1987). During other times of the year, black bears establish temporal spacing between each other and maintain these areas through a dominance hierarchy system (Pelton 1982).

Predator-Prey Relations

Black bears have very few natural predators. Bobcats, coyotes, or other black bears may occasionally kill young bears (Lariviere 2001). Most black bear mortality is human induced, predominantly by hunting. Bear mortality occurs when problem bears are removed from the population to protect property or for public safety. Vehicles also kill a number of bears annually.

Literature Cited

Bean, R.A. 2001. California’s black bear population is healthy and growing. California Game & Fish Magazine.
Big Game Hunt. 2002. Expanded elk and black bear hunting proposed – Expanded_Elk_and_Black_Bear_Hunting_Proposed_03080212.html [Homepage of California Department of Game and Fish], [Online]. Available: http://www.biggamehunt.net/sections/California/ California Department of Fish and Game. 1998. Black bear management plan. Sacramento, CA.
Grinnell, J.; Dixon, J.; Lindsdale, J. 1937. Furbearing mammals of California, their natural history, systematic status, and relations to man. Volume 2. Berkeley, CA: University of California Press. Hall, E.R. 1981. The mammals of North America. 2d ed. New York: John Wiley & Sons.

Lariviere, S. 2001. Ursus americanus. Mammalian Species 200: 1-7. Published by the American Society of Mammalogists.

Pelton, M.R. 1982. Black bear Ursus americanus. In: Chapman; J.A.; Feldhamer, G.A., eds. Wild mammals of North America: Biology, management, and economics. Baltimore, MD: The Johns Hopkins University Press; 504-514.

Rogers, L.L. 1987. Effects of food supply and kinship on social behavior, movements, and population dynamics of black bears in northeastern Minnesota. Wildlife Monograph 97.

Stephenson, J.R.; Calcarone, G.M. 1999. Southern California mountains and foothills assessment: Habitat and species conservation issues. General Technical Report GTR-PSW-172. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture.

Tremor, S.; Botta, R. (Eds.). 2000. Ursus americanus American black bear. San Diego Natural History Museum field guide [Homepage of the San Diego Natural History Museum], [Online]. Available: http:// www.sdnhm.org/fieldguide/mammals/ursu-ame.html.

Van Stralen, G.E. 1998. Home range size and habitat use of urban black bears in southern California. Northridge: California State University. Master’s thesis.

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Field Guide to Birds of Southern California

Mountain Bluebird (Sialia currucoides)


Written by: D. Gaines
Reviewed by: L. Mewaldt
Edited by: R. Duke

DISTRIBUTION, ABUNDANCE, AND SEASONALITY

A fairly common to common summer resident in sparse to open forests and other open habitats from about 1200-3700 m (4000-12,000 ft) in mountains and foothills of the state.  Most individuals winter below 1500 m (5000 ft), withdrawing from higher, snowy portions of breeding range.  Locally fairly common to abundant in Central Valley and surrounding foothills, in agricultural areas of Owens Valley, Inyo Co., Antelope Valley, Kern and Los
Angeles cos., and in arid valleys of inner Coast Ranges, as on Carrizo Plain, San Luis Obispo Co.  Less numerous and occurrence more erratic elsewhere in interior lowlands of state. Some years also winters locally throughout Mojave Desert, on coastal plains of southern California, and on Channel Islands (Grinnell and Miller 1944, Garrett and Dunn 1981).

SPECIFIC HABITAT REQUIREMENTS

Feeding:    From a low, exposed perch, hovers and stoops on insects on foliage or ground, and hawks flying insects.  Also eats berries and other small fruits, especially in winter (Martin et al. 1961, Power 1966).

Cover:    Prefers open terrain with an occasional tree, rock, fence post, power line, building, for foraging perch and other cover.  Requires suitable cavities for roosting and nesting, usually in a snag or dead portion of tree.

Reproduction:    Nest of herbaceous stems, rootlets, grasses, outer bark of shrub placed in natural cavity or woodpecker hole in snag or dead portion of tree.  Less frequently nests in crevice or cavity in rock, buiIding or other human structure; also uses nest box or nest of cliff swallow or other species (Bent 1949).

Water:    No information found.  Miller and Stebbins (1964) suggested that insect food provided adequate moisture in California deserts.

Pattern:    Breeders most numerous where meadows, grasslands, or other open habitats edge on woodland or rock formations affording suitable nesting sites.  In winter, occurs in virtually any open or sparsely wooded habitat, but shows a preference for agricultural fields and Pastures.

SPECIES LIFE HISTORY

Activity Patterns:    Yearlong, diurnal activity.

Seasonal Movements/Migration:    Breeders return to higher portions of nesting range March to June, depending on elevation and snow conditions, and depart by October or November.  Usually arrives on wintering areas in November and departs by March.

Home Range:    Estimates of breeding density include 30 per 40 ha (100 ac) in Wyoming aspen forest (Salt 1957), 15-18 per 40 ha in Wyoming (Finzel 1964), and 15.2 pairs per 40 ha in Sierra Nevada conifer forest (Bock and Lynch 1970).

Territory:    Power (1966) found territory boundary difficult to determine; inferred that 4 territories averaged 4.3 ha each (10.6 ac), range 1.8-6.8 ha (4.5-16.7 ac).  These estimates were minima; some territories “had no clear boundaries at all.”  Territory apparently centered on nest and included suitable flycatching perches and a large area of open space.  At Mt. Rainier, Washington, Jewett et al. (1953) reported that a nesting female foraged over about
2.6 ha (6.5 ac).

Reproduction:    Monogamous; lays eggs mid-April to mid-July, depending on elevation. May be double or triple-brooded.  Clutch 5-6 eggs.  Incubation 13-14 days by both sexes, and both sexes care for altricial young.  Fledging age 22-23 days (Bent 1949, Power 1966, Harrison 1978).

Niche:    Tree swallow, house wren, mountain chickadee, European starling, northern flicker and other woodpeckers, and rodents compete for nest sites.  Predators include prairie falcon and sharp-shinned hawk (Munro 1940, Marti and Braun 1975).  Numbers have declined in recent decades (Ehrlich et al. 1988).

REFERENCES

Bent, A. C.  1949.  Life histories of North American thrushes, kinglets, and their allies.  U.S.  Natl. Mus. Bull.  196.  454pp.

Bock, C. E., and J. F. Lynch.  1970.  Breeding bird populations of burned and unburned  conifer forests in the Sierra Nevada.  Condor  72:182-189.

Ehrlich, P. R., D. S. Dobkin, and D. Wheye.  1988.  The birder’s handbook.  Simon and Schuster, New York.  785pp.

Finzel, J. E.  1964.  Avian populations of four herbaceous communities in southeastern Wyoming.  Condor  66:496-510.

Garrett, K., and J. Dunn.  1981.  Birds of southern California.  Los Angeles Audubon Soc. 408pp.

Grinnell, J., and A. H. Miller.  1944.  The distribution of the birds of California.  Pac. Coast Avifauna No. 27.  608pp.

Haecker, F. W.  1948.  A nesting study of the mountain bluebird in Wyoming.  Condor 50:216-219.

Harrison, C.  1978.  A field guide to the nests, eggs and nestlings of north American birds.  W. Collins Sons and Co., Cleveland, OH.  416pp.

Jewett, S. G., W. P. Taylor, W. T. Shaw, and J. W. Aldrich. 1953.  Birds of Washington State. Univ. Washington Press, Seattle.  767pp.

Marti, C. D., and C. E. Braun.  1975.  Use of tundra habitats by prairie falcons in Colorado. Condor  77:213-214.

Martin, A. C., H. S. Zim, and A. L. Nelson.  1961.  American wildlife and plants, a guide to wildlife food habits.  Dover Publ., Inc., New York.  500pp.

Miller, A. H., and R. C. Stebbins.  1964.  The lives of desert animals in Joshua Tree National Monument.  Univ. California Press, Berkeley.  452pp.

Munro, J. A. 1940.  Food of the sharp-shinned hawk.  Condor  42:168-169. Power, H. W., III.  1966.  Biology of the mountain bluebird in Montana.  Condor  68:351-371.

Power, H. W., III.  1974.  The mountain bluebird:  sex and the evolution of foraging behavior. Ph.D. Thesis, Univ. Michigan, Ann Arbor.  405pp. Salt, G. W.  1957.  An analysis of avifaunas in the Teton Mountains and Jackson Hole,
Wyoming.  Condor  59:373-393.

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Field Guide to Amphibians of Southern California

California Tiger Salamander (Ambystoma californiense)



General Distribution

California tiger salamander occurs from the northern Santa Lucia Range south to the Santa Ynez River, adjacent to the Los Padres National Forest. Based on the distribution map in Jennings and Hayes (1994), California tiger salamander occurs in upper portions of the Carmel River and Little Sur River watersheds either on or near the Los Padres National Forest. No localities are shown in the southern Santa Lucia Mountains, but the species does occur in the lower Sisquoc River and Santa Ynez River watersheds. These southernmost localities appear to correspond with the Solomon Hills and Santa Rita Hills, respectively, where Sam Sweet has found California tiger salamanders (Stephenson and Calcarone 1999). Both locations are at least 5 miles (8 kilometers) west of the Los Padres National Forest. The extent to which potential habitat occurs on National Forest System lands are uncertain. On Sept 13, 2002 the U.S. Fish and Wildlife Service, in response to a Forest Service species list request, did not include the California tiger salamander due to the low potential habitat on National Forest System lands.

Systematics

California tiger salamander was first described as a distinct species by Gray in 1853 from specimens collected in Monterey (65 Federal Register 57242, September 21, 2000). Storer (1925) also considered California tiger salamander a distinct species. Although some researchers consider California tiger salamander a subspecies of tiger salamander (Ambystoma tigrinum), most consider it a distinct species because it differs in coloration and natural history from the western subspecies of A. tigrinum. In addition, recent genetic comparisons with subspecies of A. tigrinum indicate that California tiger salamander is well differentiated from all of these subspecies (65 Federal Register 57242, September 21, 2000; Petranka 1998). California tiger salamander in Santa Barbara County constitutes a single genetic population, reproductively isolated from the rest of the California tiger salamander population (65 Federal Register 57242, September 21, 2000).

Habitat Requirements

California tiger salamander is a lowland species restricted to grasslands and low foothill regions where its breeding habitat (long-lasting rain pools) occurs. Permanent aquatic sites are unlikely to be used for breeding unless they lack fish predators (Jennings and Hayes 1994). California tiger salamanders also require dry-season refuge sites in the vicinity of breeding sites (within 1 mile [1.6 kilometers]) (Jennings and Hayes 1994). Ground squirrel burrows are important dry-season refuge sites for adults and juveniles (Loredo and others 1996).

Reproduction

Adult California tiger salamanders move from subterranean burrow sites to breeding pools during November–February after warm winter and spring rains (Jennings and Hayes 1994). Male salamanders may arrive at breeding sites sooner than females (Loredo and Van Vuren 1996, Twitty 1941). Eggs are probably laid in January–February at the height of the rainy season (Storer 1925). Eggs are deposited in shallow water and attached to grass stalks, dead weeds, or other vegetation under the water surface (Storer 1925, Twitty 1941). Development from laying through metamorphosis requires 9-12 weeks (Anderson 1968, Feaver 1971). Over-summering California tiger salamander larvae have been observed (Jennings and Hayes 1994), and over-wintering larvae have been observed in numerous stock ponds at the Los Vaqueros watershed near Livermore, California (Alvarez in Solano Co. HCP).

Daily/Seasonal Activity

During winter, California tiger salamanders take refuge in damp places near the surface of the ground during the day and emerge at night to forage (Storer 1925). During dry weather, they take refuge in ground squirrel burrows, other burrows, or in crevices in the soil (Loredo and others 1996). Once established in underground burrows, these salamanders may move short distances within burrows or overland to other burrows, generally during wet weather (65 Federal Register 57242, September 21, 2000).

Diet and Foraging

California tiger salamander larvae eat algae and various invertebrates including water fleas, copopods, and fairy shrimp (Anderson 1968). Larger salamander larvae consume amphibian larvae (Anderson 1968). The diet of adult California tiger salamanders probably consists of earthworms, snails, fish, insects, and small mammals (Stebbins 1959).

Predator-Prey Relations

Native predators of California tiger salamander adults and larvae include great blue heron (Ardea herodias), egret (Casmerodius albus), common garter snake (Thamnophis sirtalis), and larger western spadefoot (Scaphiopus hammondii) larvae (65 Federal Register 57242, September 21, 2000; Barry and Shaffer 1994). Baldwin and Stanford (1986) observed a western pond turtle (Clemmys marmorata) pursuing a larval California tiger salamander and an adult red-legged frog (Rana aurora) ingesting a larval California tiger salamander. Other predators include bullfrog (Rana catesbeiana), Louisiana red swamp crayfish (Procambarus clarki), mosquitofish (Gambusia affinis) and other introduced fishes (65 Federal Register 57242, September 21, 2000; Anderson 1968; Jennings and Hayes 1994). California tiger salamander is known to prey on western spadefoot larvae and Pacific treefrog (Hyla regilla) larvae (Anderson 1968).

Literature Cited

Alvarez, J.A. 2003. California tiger salamander species account. In: Solano County Habitat Conservation Plan. [Online]. Available: http://www.scwa2.com/hcp/.
Anderson, P.R. 1968. The reproductive and developmental history of the California tiger salamander. Fresno, CA: Fresno State College. MA thesis.

Baldwin, K.S.; Stanford, R.A. 1987. Life History notes: Ambystoma tigrinum californiense predation. Herpetological Review 18(2): 33.
Barry, S.J.; Shaffer, H.B. 1994. The status of the California tiger salamander (Ambystoma californiense) at Lagunita: A 50-year update. Journal of Herpetology 24(2): 159-164.
Feaver, P.E. 1971. Breeding pool selection and larval mortality of three California amphibians: Ambystoma tigrinum californiense Gray, Hyla regilla Baird and Girard, and Scaphiopus hammondi hammondi Girard. Fresno, CA: Fresno State College. MA thesis.
Fisher, R.N.; Shaffer, H.B. 1996. The decline of amphibians in California’s great Central Valley. Conservation Biology 10: 1387-1397.
Jennings, M.R.; Hayes, M.P. 1994. Amphibian and reptile species of special concern in California. Rancho Cordova, CA: Inland Fisheries Division, California Department of Fish and Game.
Loredo, I.; Van Vuren, D. 1996. Reproductive ecology of a population of the California tiger salamander. Copeia 1996: 895-901.
Loredo, I.; Van Vuren, D.; Morrison, M.L. 1996. Habitat use and migration behavior of the California tiger salamander. Journal of Herpetology 30(2): 282-285.
Petranka, J.W. 1998. Salamanders of the United States and Canada. Washington and London: Smithsonian Institution and Press.
Stebbins, R.C. 1959. Reptiles and amphibians of the San Francisco Bay region. Berkeley and Los Angeles, CA: University of California Press.
Stebbins, R.C. 1985. A field guide to western reptiles and amphibians. 2d ed., revised. Boston, MA: Houghton Mifflin Company.
Stephenson, J.R.; Calcarone, G.M. 1999. Southern California mountains and foothills assessment: Habitat and species conservation issues. General Technical Report PSW-GTR-172. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture.
Storer, T.I. 1925. A synopsis of the amphibia of California. University of California Publications in Zoology 27: 1-342.
Twitty, V.C. 1941. Data on the life history of Ambystoma tigrinum californiense Gray. Copeia 1941: 1- 4.
U.S. Fish and Wildlife Service. 2002. Final Rule to list the Santa Barbara County distinct population segment of California tiger as endangered salamander. 65 Federal Register 57242, September 21, 2000.

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Coon Hollow Campground

Coon Hollow Campground    33°26’52”N 114°54’04”W Elevation 650′

 

The Mule Mountains Some shade at the campground Topographic Map of Area
(Click to enlarge for printing)


Location: Southeast Imperial County

Access: I-10 to Wiley’s Well Road, exit south about 12 miles.

Facilities: 27 sites, pit toilets. No water.

Season: Open year round. Part of the BLMs LTVA system from September thru April.

Fees: Per LTVA system, $20/week -or- $100/season.

Nearby Hiking Trails: Too many to list. Consult Topo map.

Nearby 4X4 Trails: Too many to list. Consult Topo map.

Managing Agency: US Bureau of Land Management.

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Oak Grove Campground

Oak Grove Campground    33°23’11”N 116°47’20”W Elevation 2765′

Campground Entrance Each site has a picnic table Topographic Map of Area
(Click to enlarge for printing)


Location: Cleveland National Forest

Access: 6.25 miles south of Aguanga on Hwy 79.

Facilities: 81 sites, water, toilets, grills, firerings.

Season: Open year round.

Fees: $15.

Nearby Hiking Trails: Oak Grove Trail.

Nearby 4X4 Trails: No information available.

Managing Agency: US Forest Service

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Indian Flats

Indian Flats Campground    33°20’59”N 116°39’42”W Elevation 3615′

South view from campsite Campground in the sage and scrub Topographic Map of Area
(Click to enlarge for printing)


Location: Cleveland National Forest

Access: Hwy 79 northeast of Warner Springs, head north on Indian Flats Rd.

Facilities: 17 sites. USFS pipes in water, may be unreliable. Bring water.

Season: Open year round.

Fees: No Fee. Adventure Pass Required

Nearby Hiking Trails: No information available.

Nearby 4X4 Trails: Whew! Just getting to this spot is an adventure.

Managing Agency: US Forest Service

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