California Tiger Salamander

Status

California tiger salamander (Ambystoma californiense) is a large amphibian that is restricted to California. The Central Valley population of California tiger salamander is Federally-listed as Threatened (August 4, 2004) and the Sonoma (July 22, 2002) and Santa Barbara populations (January 19, 2000) are Federally-listed as Endangered under the Federal Endangered Species Act. On March 3, 2010, the California Fish and Game Commission voted to designate the California tiger salamander as threatened state-wide under the California Endangered Species Act. This species ranges along coastal regions from Sonoma County south to Santa Barbara County and in the Central Valley and Sierra Nevada foothills from Yolo County south to Kern County. Populations of this species have declined throughout California due to loss and fragmentation of breeding and upland habitat, and the encroachment of non-native predators, such as bullfrog.

Description

California tiger salamander is a large, stocky, terrestrial salamander with small eyes and a broad, rounded snout. Adult males are about 8 inches long and females are slightly smaller at about 7 inches in length. The coloration of males and females are similar and generally consists of white or pale yellow spots or bars on a black background on the back and sides. The belly varies from almost uniform white or pale yellow to an alternating pattern of white or pale yellow and black. The eyes of adult tiger salamanders are generally small and protrude from their heads.

Habitat Requirements

California tiger salamander is most commonly found in annual grassland and oak savannah habitats where lowland aquatic sites are available for breeding. Adults require vernal pools or other ephemeral bodies of water for breeding and egg-laying, but will occasionally use permanent human-made ponds if predatory fish and bullfrogs are absent. Adult tiger salamanders remain underground for most of the year in small mammal burrows in the vicinities of breeding ponds. The first significant rainfall of November usually initiates adult migration to breeding ponds. Breeding and egg-laying typically occurs from December through early February. Clusters of eggs are deposited at breeding sites on both submerged and emergent vegetation and eggs hatch after 10 to 14 days. Larvae typically transform during late spring or early summer and disperse from the breeding sites to nearby upland areas. California tiger salamanders cannot dig their own burrows, and therefore only occur in association with burrowing mammals such as western ground squirrels. Adults of this species have been observed up to 1.3 miles from breeding ponds, but are most often found less than a mile from the nearest aquatic breeding site, depending on local topographic and vegetation conditions.

Adult and metamorphosed (transformed) juvenile salamanders sit and wait for their prey which includes earthworms, snails, insects, fish and some small mammals. Aquatic larvae feed on small plankton, arthropods, amphipods, small mollusks and insect larvae.

Local Occurrence

California tiger salamanders occur at the Mesa Ridge Preserve in Santa Clara County and the Haera Ranch Preserve in Alameda County.