California Tiger Salamander

Taxobox
name = California Tiger Salamander
status = VU | status_system = IUCN3.1
trend = down


image_width = 275px
image_caption = Photo by Gary Nafis
regnum = Animalia
divisio = Chordata
classis = Lissamphibia
ordo = Caudata
familia = Ambystomatidae
genus = "Ambystoma"
species = "A. californiense"
binomial = "Ambystoma californiense"
binomial_authority = Gray, 1853

The California tiger salamander ("Ambystoma californiense") is an endangered amphibian native to Northern California. Previously considered to be a Tiger Salamander subspecies, the California tiger salamander, which is endemic, was recently designated a separate species.

Description

The California tiger salamander is a relatively large, secretive amphibian. Adults can grow to a length of about 8–10 inches (20–25 cm). It has a stocky body and a broad rounded snout. Adults are black with yellow or cream spots; larvae are greenish-grey in color. The California tiger salamander has brown protruding eyes with black pupils.

Habitat and range

The California tiger salamander depends on water for reproduction, its habitat is limited to the vicinity of large, fishless vernal pools or similar water bodies. It occurs at elevations up to 1000 m (3200 ft).

It occurs from Sonoma County, especially in the Laguna de Santa Rosa (outside the flood plain), south to Santa Barbara County, in vernal pool complexes and isolated ponds along the Central Valley from Colusa County to Kern County, and in the coastal range. Both the Sonoma and Santa Barbara populations are listed as endangered since 2000 and 2003, respectively. On 8/4/04, the United States Fish and Wildlife Service listed the California tiger salamander as "threatened" within the Central Valley Distinct Population Segment. In doing so, the status of the Santa Barbara and Sonoma county populations was changed from endangered to threatened. However, the Santa Barbara and Sonoma County populations were returned to Endangered status on 8/19/05. The main threat to the salamanders is habitat destruction through human interaction.

Life cycle

Adults spend the majority of their lives underground, in burrows created by other animals such as ground squirrels: the salamanders themselves are poorly equipped for burrowing. Little is known about their underground life. This underground phase has often been referred to as estivation (the summertime equivalent of hibernation), but true estivation has never been observed, and fiber optic cameras in burrows have allowed researchers to witness salamanders actively foraging.

Breeding takes place after the first rains in late fall and early winter, when the wet season allows the salamanders to migrate to the nearest pond, a journey that may be as far as a mile and take several days. The eggs, which the female lays in small clusters or singly, hatch after some 10 to 14 days.

The larval period lasts for three to six months. However, California tiger salamander larvae may also "overwinter". Transformation for overwintering larvae may take 13 months or more. Recent discoveries, such as overwintering, have management implications for this threatened species, particulalry when aquatic habitat under goes modification. The larvae feed on other small invertebrates, including tadpoles. When their pond dries, they resorb their gills, develop lungs, and then the metamorphs leave the pond in search of a burrow.

California tiger salamanders are believed to have relatively long life spans, ten years or more.

ee also

*Vernal pools

References

* Database entry includes a range map, a brief justification of why this species is vulnerable, and the criteria used
* [http://www.dfg.ca.gov/bdb/html/cnddb.html California Natural Diversity Database] California Natural Diversity Database and others

External links

* [http://www.fws.gov/sacramento/es/santa_rosa_conservation.html Santa Rosa Plain Conservation Strategy ] Santa Rosa Plain Conservation Strategy
* [http://www.dfg.ca.gov/whdab/html/A001.html Description] from the California Department of Fish and Game.
* [http://www.npwrc.usgs.gov/narcam/idguide/acalif.htm USGS Field Guide]
* [http://www-envirinfo.llnl.gov/wildside_salamanders.pdf Michael van Hattem] from the Lawrence Livermore National Laboratory on the California Tiger Salamander. (PDF file, 826 kB)
* [http://sacramento.fws.gov/es/animal_spp_acct/california_tiger_salamander.htm Species account & Federal Records] from the U.S. Fish and Wildlife Service.