California Tiger Salamander
Encyclopedia
The California tiger salamander (Ambystoma californiense) is a vulnerable
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...

 amphibian native to Northern California
Northern California
Northern California is the northern portion of the U.S. state of California. The San Francisco Bay Area , and Sacramento as well as its metropolitan area are the main population centers...

. Previously considered to be a Tiger Salamander
Tiger Salamander
The Tiger Salamander is a species of Mole Salamander. The proper common name is the Eastern Tiger Salamander, to differentiate from other closely related species.-Description:...

 subspecies, the California tiger salamander was recently designated a separate species again. Two communities (in Sonoma
Sonoma County, California
Sonoma County, located on the northern coast of the U.S. state of California, is the largest and northernmost of the nine San Francisco Bay Area counties. Its population at the 2010 census was 483,878. Its largest city and county seat is Santa Rosa....

 and Santa Barbara County
Santa Barbara County, California
Santa Barbara County is a county located in the southern portion of the U.S. state of California, on the Pacific coast. As of 2010 the county had a population of 423,895. The county seat is Santa Barbara and the largest city is Santa Maria.-History:...

) are classified as "endangered".

Description

The California tiger salamander is a relatively large, secretive amphibian endemic to California. Adults can grow to a length of about 7–8 inches. 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 vernal pools for reproduction, its habitat is limited to the vicinity of large, fishless vernal pool
Vernal pool
Vernal pools, also called vernal ponds or ephemeral pools, are temporary pools of water. They are usually devoid of fish, and thus allow the safe development of natal amphibian and insect species...

s or similar water bodies. It occurs at elevations up to 1000 m (3200 ft). Adults migrate at night from upland habitats to aquatic breeding sites during
the first major rainfall events of fall and early winter and return to upland habitats after breeding.

Historically, the California tiger salamander probably occurred in grassland habitats throughout much of the state. It occurs from Sonoma County
Sonoma County, California
Sonoma County, located on the northern coast of the U.S. state of California, is the largest and northernmost of the nine San Francisco Bay Area counties. Its population at the 2010 census was 483,878. Its largest city and county seat is Santa Rosa....

, especially in the Laguna de Santa Rosa
Laguna de Santa Rosa
The Laguna de Santa Rosa is a long wetland complex that drains a 254-square mile watershed encompassing most of the Santa Rosa Plain in Sonoma County, California, USA.-Description:...

 (outside the floodplain
Floodplain
A floodplain, or flood plain, is a flat or nearly flat land adjacent a stream or river that stretches from the banks of its channel to the base of the enclosing valley walls and experiences flooding during periods of high discharge...

), south to Santa Barbara County
Santa Barbara County, California
Santa Barbara County is a county located in the southern portion of the U.S. state of California, on the Pacific coast. As of 2010 the county had a population of 423,895. The county seat is Santa Barbara and the largest city is Santa Maria.-History:...

, in vernal pool complexes and isolated ponds along the Central Valley from Colusa County
Colusa County, California
Colusa County is a county located in the Central Valley of the U.S. state of California, northwest of state capital Sacramento. As of the 2010 census, its population was 21,419. The county seat is Colusa.-History:...

 to Kern County
Kern County, California
Spreading across the southern end of the California Central Valley, Kern County is the fifth-largest county by population in California. Its economy is heavily linked to agriculture and to petroleum extraction, and there is a strong aviation and space presence. Politically, it has generally...

, and in the coastal range
Pacific Coast Ranges
The Pacific Coast Ranges and the Pacific Mountain System are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico...

. Both the Sonoma and Santa Barbara populations are listed as endangered
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

 since 2000 and 2003, respectively. On August 4, 2004, the United States Fish and Wildlife Service
United States Fish and Wildlife Service
The United States Fish and Wildlife Service is a federal government agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats...

 listed the California tiger salamander as threatened
Threatened species
Threatened species are any speciesg animals, plants, fungi, etc.) which are vulnerable to endangerment in the near future.The World Conservation Union is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories,...

 within the Central Valley distinct population segment
Distinct population segment
A distinct population segment is the smallest division of a taxonomic species permitted to be protected under the U.S. Endangered Species Act. Species, as defined in the Act for listing purposes, is a taxonomic species or subspecies of plant or animal, or in the case of vertebrate species, a...

. The Santa Barbara and Sonoma County populations were returned to endangered status on August 19, 2005.

There are six populations, which are found in: (1) Sonoma County; (2) the Bay Area, (Stanislaus County, western Merced, and the majority of San Benito counties); (3) the Central Valley; (4) southern San Joaquin Valley (5) the Central Coast Range and (6) Santa Barbara County

The loss of California tiger salamander populations has been due primarily to habitat loss within its historic range, although introduced predators such as bullfrog
Bullfrog
The American bullfrog , often simply known as the bullfrog in Canada and the United States, is an aquatic frog, a member of the family Ranidae, or “true frogs”, native to much of North America. This is a frog of larger, permanent water bodies, swamps, ponds, and lakes, where it is usually found...

s might also be an issue.

Life cycle

Adults spend the majority of their lives underground, in burrows created by other animals such as ground squirrels and gophers: 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. Adults are known to eat earthworms, snails, insects, fish, and even small mammals but adult California tiger salamanders eat very little.

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 10 to 14 days.

The larval period lasts for 3 to 6 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, particularly when aquatic habitat under goes modification. The larvae feed on other small invertebrates, including tadpole
Tadpole
A tadpole or polliwog is the wholly aquatic larval stage in the life cycle of an amphibian, particularly that of a frog or toad.- Appellation :...

s. When their pond dries, they resorb their gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...

s, develop lungs, and then the metamorphs leave the pond in search of a burrow.

California tiger salamanders can live up to 12 to 15 years.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK