California Tiger Salamander (Ambystoma californiense)
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.
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).
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).
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).
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).
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).
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.