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Home/Species/ California Tiger Salamander

Ambystoma californiense

Gray, 1853

California Tiger Salamander

G3Vulnerable Found in 11 roadless areas NatureServe Explorer →
G3VulnerableGlobal Rank
VulnerableIUCN
Very high - highThreat Impact
California tiger Salamander (Ambystoma californiense). Photo by U.S. Fish & Wildlife Service, Public Domain (U.S. Government Work), via ECOS.
U.S. Fish & Wildlife Service, https://www.usa.gov/government-works
Identity
Unique IDELEMENT_GLOBAL.2.104488
Element CodeAAAAA01180
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVertebrate Animal
IUCNVulnerable
Endemicendemic to a single state or province
KingdomAnimalia
PhylumCraniata
ClassAmphibia
OrderCaudata
FamilyAmbystomatidae
GenusAmbystoma
Synonyms
Ambystoma tigrinum californienseCope, 1889
Other Common Names
California tiger salamander (EN)
Concept Reference
Collins, J. T. 1990. Standard common and current scientific names for North American amphibians and reptiles. 3rd ed. Society for the Study of Amphibians and Reptiles. Herpetological Circular No. 19. 41 pp.
Taxonomic Comments
Formerly regarded as a subspecies of Ambystoma tigrinum. See Kraus (1988), Shaffer et al. (1991), and Jones et al. (1993) for phylogenetic analyses of North American Ambystoma; these analyses treated californiense as a distinct species.

Based on genetic analysis, there are six populations of California tiger salamanders, distributed as follows: (1) Santa Rosa area of Sonoma County; (2) Bay Area (central and southern Alameda, Santa Clara, western Stanislaus, western Merced, and the majority of San Benito counties); (3) Central Valley (Yolo, Sacramento, Solano, eastern Contra Costa, northeast Alameda, San Joaquin, Stanislaus, Merced, and northwestern Madera counties); (4) southern San Joaquin Valley (portions of Madera, central Fresno, and northern Tulare and Kings counties); (5) Central Coast Range (southern Santa Cruz, Monterey, northern San Luis Obispo, and portions of western San Benito, Fresno, and Kern counties); and (6) Santa Barbara County (Shaffer and Trenham 2002).

USFWS (2000, 2002) reviewed the biogeographical and genetic information supporting the recognition of the Santa Barbara County population and Sonoma County population as distinct population segments under the U.S. Endangered Species Act.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2025-05-18
Change Date2025-05-18
Edition Date2025-05-18
Edition AuthorsHammerson, G. (2011); rev. R L. Gundy (2025)
Threat ImpactVery high - high
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences> 300
Rank Reasons
This species is endemic to California. There are nearly 600 extant occurrences. However, only about 10% are currently protected. This species is highly threatened by habitat loss due to conversion to agriculture and urban development, habitat degradation, invasive species, disease, and road mortality.
Range Extent Comments
This species is endemic to California, United States. The species has a discontinuous distribution in west-central California: coast ranges between Sonoma and Santa Barbara counties, Central Valley and surrounding foothills from southern Colusa County to northwestern Kern County on the west side of the valley and southern Butte County to northern Tulare County on the east side. Elevational range from near sea level to 1054 m. Using extant occurrences in the California Natural Diversity Database (CNDDB) (2025), range extent is estimated to be 74,502 km² (RARECAT 2025).
Occurrences Comments
There are 592 extant occurrences in the California Natural Diversity Database (2025).
Threat Impact Comments
The primary threat to this species is the loss and degradation of habitat due to conversion of natural habitat to agriculture and urban development (USFWS 2021, USFWS 2022, USFWS 2023). Twenty years after listing, this species has still not received adequate habitat protection to meet the recovery criteria for any of the distinct population segments (USFWS 2021, USFWS 2022, USFWS 2023). Another form of habitat degradation has been the loss of small burrowing mammals, which provide essential underground habitat for this salamander (USFWS 2021, USFWS 2022, USFWS 2023).

Other secondary threats include invasive species, disease, and pollution. Invasive predatory animals (bullfrogs, crayfish, various fishes) that may temporarily occupy salamander breeding habitat consume eggs and larvae. Hybridization with the barred tiger salamander (Ambystoma mavortium) is a concern due to genetic swamping, competition, and predation (Cooper and Shaffer 2020, USFWS 2021, USFWS 2022, USFWS 2023). A trematode (Ribeiroia ondatrae) transmitted from snails and transported by birds was associated with a large mortality event in Santa Cruz County in 2019 (Keller et al. 2021). Experimental laboratory studies have shown that ranavirus carried by other tiger salamander species can be very fatal for this species (Picco et al. 2007). Chytrid fungus (Batrachochytrium dendrobatidis) has been detected in this species, but has not been attributed to any large-scale mortality events (Padgett-Flohr and Longcore 2005, USFWS 2016). Use of pesticides for mosquito abatement may reduce food resources for salamanders (USFWS 2023). Contaminated runoff from roads may adversely affect salamanders in breeding sites (USFWS 2022). Road mortality can also be a threat in some areas.
Ecology & Habitat

Description

Adults are black with large pale yellow spots mainly in the dorsolateral regions, sometimes with a prominent cream band on the lower sides, usually 12 costal grooves, a broad head, small eyes, and tubercles on the soles of the feet; pond-type larva (but lacks balancers), with three large pairs of gills, vomerine teeth in U-shaped pattern, and dorsal fin extending to region of axilla; adults usually are about 15-22 cm in total length (Stebbins 1951, 1985; Behler and King 1979).

Diagnostic Characteristics

The following pertains to metamorphosed adults. Differs from A. MACRODACTYLUM in lacking a distinct dorsal stripe or stripelike row of spots. Differs from A. GRACILE in having distinct dorsal markings and tubercles on the underside of the feet and by lacking parotoid glands and a glandular ridge on the tail. Differs from plethodontid salamanders in lacking a nasolabial groove. Differs from other subspecies primarily in color pattern.

Habitat

Lives in vacant or mammal-occupied burrows (e.g., California ground squirrel, valley pocket gopher) (Trenham 2001), occasionally other underground retreats, throughout most of the year; in grassland, savanna, or open woodland habitats. Sonoma County populations is closely associated with the presence of gopher burrows (see USFWS 2003). Lays eggs on submerged stems and leaves, in shallow ephemeral or semipermanent pools and ponds that fill during heavy winter rains or in permanent ponds (Alvarez 2004); adults spend little time in breeding sites.

Ecology

See Holland et al. (1990) for a description of late summer overland movements of juveniles and mass mortality of newly metamorphosed individuals.

Reproduction

Breeding occurs mainly December-February, after rains fill pools and ponds. Fertilization internal. Eggs are laid singly or in small clusters, hatch in 2-4 weeks. Larvae transform in about 4 months (Behler and King 1979), as water recedes in late spring or summer, but larvae may overwinter in permanent ponds (Alvarez 2004). May not breed in drought years when ponds fail to fill. Production of metamorphs tends to be "boom or bust" at a given site (Loredo and Van Vuren 1996).

In a pond in Monterey County, most individuals matured sexually at 4-5 years, but less than 50 percent returned to breed a second time; numbers of breeding adults varied by more than a factor of four over several years, and annual juvenile production ranged from 121-775 metamorphs. This level of reproduction indicated that the population was a reproductive sink during the period of the study (Trenham et al. 2000).
Terrestrial Habitats
Woodland - HardwoodSavannaGrassland/herbaceous
Palustrine Habitats
TEMPORARY POOLHERBACEOUS WETLAND
Other Nations (1)
United StatesN2
ProvinceRankNative
CaliforniaSNRYes
Threat Assessments
ThreatScopeSeverityTiming
1 - Residential & commercial developmentRestricted (11-30%)Extreme - moderateHigh (continuing)
1.1 - Housing & urban areasRestricted (11-30%)Extreme - moderateHigh (continuing)
1.2 - Commercial & industrial areasRestricted (11-30%)Extreme - moderateHigh (continuing)
2 - Agriculture & aquacultureLarge (31-70%)Extreme - moderateHigh (continuing)
2.1 - Annual & perennial non-timber cropsLarge (31-70%)Extreme - moderateHigh (continuing)
4 - Transportation & service corridorsSmall (1-10%)Moderate - slightHigh (continuing)
4.1 - Roads & railroadsSmall (1-10%)Moderate - slightHigh (continuing)
8 - Invasive & other problematic species, genes & diseasesPervasive - largeModerate - slightHigh (continuing)
8.1 - Invasive non-native/alien species/diseasesPervasive - largeModerate - slightHigh (continuing)
9 - PollutionUnknownUnknownHigh (continuing)
9.2 - Industrial & military effluentsUnknownUnknownHigh (continuing)
9.3 - Agricultural & forestry effluentsUnknownUnknownHigh (continuing)

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Roadless Areas (11)
California (11)
AreaForestAcres
Bear MountainLos Padres National Forest913
Bear MountainLos Padres National Forest913
Black ButteLos Padres National Forest5,116
Black ButteLos Padres National Forest5,116
Chalk PeakLos Padres National Forest7,472
Kings RiverSierra National Forest52,999
La BreaLos Padres National Forest14,031
Oat Mtn.Sequoia National Forest12,223
Oat Mtn.Sequoia National Forest12,223
Sycamore SpringsSierra National Forest10,015
Tepusquet PeakLos Padres National Forest5,821
References (45)
  1. Alvarez, J. A. 2004a. Use of artificial egg laying substrate to detect California tiger salamanders (<i>Ambystoma californiense</i>). Herpetological Review 35:45-46.
  2. Alvarez, J. A. 2004b. Overwintering California tiger salamander (<i>Ambystoma californiense</i>) larvae. Herpetological Review 35:344.
  3. Austin, C. C. and H. B. Shaffer 1992. Short, medium, and long-term repeatability of locomotor performance in the tiger salamander, <i>Ambystoma californiens</i>e. Functional Ecology 6(2):145-153.
  4. Barry, S. J., and H. B. Shaffer. 1994. The status of the California tiger salamander (AMBYSTOMA CALIFORNIENSE) at Lagunita: a 50-year update. Journal of Herpetology 28:159-164.
  5. Behler, J. L., and F. W. King. 1979. The Audubon Society field guide to North American reptiles and amphibians. Alfred A. Knopf, New York. 719 pp.
  6. Blackburn, L., P. Nanjappa, and M. J. Lannoo. 2001. An Atlas of the Distribution of U.S. Amphibians. Copyright, Ball State University, Muncie, Indiana, USA.
  7. Brehme, C. S., J. A. Tracy, B. A. I. Ewing, M. T. Hobbs, A. E. Launer, T. A. Matsuda, E. M. C. Adelsheim, and R. N. Fisher. 2021. Responses of migratory amphibians to barrier fencing inform the spacing of road underpasses: a case study with California tiger salamanders (<i>Ambystoma californiense</i>) in Stanford, CA, USA. Global Ecology and Conservation 31: e01857.
  8. California Natural Diversity Database (CNDDB). 2025. RareFind Version 5.3.0. California Department of Fish and Game, Sacramento.
  9. Collins, J. T. 1990. Standard common and current scientific names for North American amphibians and reptiles. 3rd ed. Society for the Study of Amphibians and Reptiles. Herpetological Circular No. 19. 41 pp.
  10. Cooper, R. D., and H. B. Shaffer. 2020. Allele-specific expression and gene regulation help explain transgressive thermal tolerance in non-native hybrids of the endangered California tiger salamander (<i>Ambystoma californiense</i>). Molecular Ecology 30(4): 987-1004.
  11. Crother, B. I. (editor). 2017. Scientific and standard English names of amphibians and reptiles of North America north of Mexico, with comments regarding confidence in our understanding. 8th edition. SSAR Herpetological Circular 43:1-104. [Updates in SSAR North American Species Names Database at: https://ssarherps.org/cndb]
  12. Davidson, C., H. B. Shaffer, and M. R. Jennings. 2002. Spatial tests of the pesticide drift, habitat destruction, UV-B, and climate-change hypotheses for California amphibian declines. Conservation Biology 16:1588-1601.
  13. Frost, D.R. 2020. Amphibian Species of the World: an Online Reference. Version 6.0. American Museum of Natural History, New York, USA. Online: http://research.amnh.org/herpetology/amphibia/index.html
  14. Holland, D. C., M. P. Hayes, and E. McMillan. 1990. Late summer movement and mass mortality in the California tiger salamander (AMBYSTOMA CALIFORNIENSE). Southwestern Naturalist 35:217-220.
  15. Holland, R. F. 1998. Great Valley vernal pool distribution, photorevised. Pages 71-75 in C. W. Witham et al., editors. Ecology, conservation, and management of vernal pool ecosystems. California Native Plant Society, Sacramento.
  16. Keller, S., C. L. Roderick, C. Caris, D. A. Grear, and R. A. Cole. 2021. Acute mortality in California tiger salamander (<i>Ambystoma californiense</i>) and Santa Cruz long-toed salamander (<i>Ambystoma macrodactylum croceum</i>) caused by <i>Ribeiroia ondatrae</i> (Class: Trematoda). International Journal for Parasitology: Parasites and Wildlife 16: 255-261.
  17. Kraus, F. 1988. An empirical evaluation of the use of the ontogeny polarization criterion in phylogenetic inference. Systematic Zoology 37:106-141.
  18. Loredo, I., and D. Van Vuren. 1996. Reproductive ecology of a population of the California tiger salamander. Copeia 1996:895-901.
  19. Loredo, I., D. Van Vuren, and M. L. Morrison. 1996. Habitat use and migration of the California tiger salamander. Journal of Herpetology 30:282-285.
  20. Orloff, S. G. 2011. Movement patterns and migration distances in an upland population of California tiger salamander (<i>Ambystoma californiense</i>). Herpetological Conservation and Biology 6(2): 266–276.
  21. Padgett-Flohr, G. E., and J. E. Longcore. 2005. <i>Ambystoma californiense</i>. Fungal infection. Herpetological Review 36:50-51.
  22. Picco, A. M., J. L. Brunner, and J. P. Collins. 2007. Susceptibility of the endangered California tiger salamander, <i>Ambystoma californiense</i>, to ranavirus infection. Journal of Wildlife Diseases, 43(2): 286–290.
  23. <p>NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2025. Version: 2.1.1 (released April 04, 2025).</p>
  24. Shaffer, H. B., J. M. Clark, and F. Kraus. 1991. When molecules and morphology clash: a phylogenetic analysis of the North American ambystomatid salamanders (Caudata: Ambystomatidae). Systematic Zoology 40:284-303.
  25. Shaffer, H. B., R. N. Fisher, and S. E. Stanley. 1993. Status report: the California tiger salamander (AMBYSTOMA CALIFORNIENSE). Final report to the California Department of Fish and Game.
  26. Stebbins, R. C. 1985a. A field guide to western reptiles and amphibians. Second edition. Houghton Mifflin Company, Boston, Massachusetts. xiv + 336 pp.
  27. Storer, T. I. 1925. A synopsis of the Amphibia of California. University of California Publications in Zoology 27:1-342.
  28. Trenham, P.C. 1998.Demography, migration, and metapopulation structure of pond breeding salamanders. Ph.D. dissertation, University of California, Davis. 96 pp.
  29. Trenham, P. C. 2001. Terrestrial habitat use by adult California tiger salamanders. Journal of Herpetology 35:343-346.
  30. Trenham, P. C., H. B. Shaffer, W. D. Koenig, and M. R. Stromberg. 2000. Life history and demographic variation in the California tiger salamander (AMBYSTOMA TIGRINUM). Copeia 2000:365-377.
  31. U.S. Fish and Wildlife Service, Sacramento Fish and Wildlife Office. 2009. Species Account, California Tiger Salamander, <i>Ambystoma californiense</i>. Sacramento Fish and Wildlife Office, Sacramento, California. 4 pp. Online at: https://www.fws.gov/sacramento/es_species/Accounts/Amphibians-Reptiles/ca_tiger_salamander/documents/california_tiger_salamander.pdf
  32. U.S. Fish and Wildlife Service (USFWS). 13 June 2002. Review of species that are candidates or proposed for listing as endangered or threatened; annual notice of findings on recycled petitions; annual description of progress on listing actions. Federal Register 67(114):40657-40679.
  33. U.S. Fish and Wildlife Service (USFWS). 14 December 2005. Designation of critical habitat for the Sonoma County Distinct Population Segment of the California tiger salamander. Federal Register 70(239):74138-74163.
  34. U.S. Fish and Wildlife Service (USFWS). 19 January 2000. Emergency rule to list the Santa Barbara County distinct population of the California tiger salamander as endangered. Federal Register 65(12):3096-3109. Proposal to list the Santa Barbara County distinct population of the California tiger salamander as endangered. Federal Register 65(12):3110-3111.
  35. U.S. Fish and Wildlife Service (USFWS). 19 March 2003. Determination of endangered status for the Sonoma County distinct population segment of the California tiger salamander. Federal Register 68(53):13498-13520.
  36. U.S. Fish and Wildlife Service (USFWS). 2002. Candidate and listing priority assignment form. California tiger salamander (Sonoma County Distinct Population Segment).
  37. U.S. Fish and Wildlife Service (USFWS). 2016. Recovery plan for the Santa Barbara County Distinct Population Segment of the California tiger salamander (<i>Ambystoma californiense</i>). U.S. Fish and Wildlife Service, Pacific Southwest Region, Ventura, California. vi + 87 pp.
  38. U.S. Fish and Wildlife Service (USFWS). 2017. Recovery Plan for the Central California Distinct Population Segment of the California Tiger Salamander (Ambystoma californiense). U.S. Fish and Wildlife Service, Pacific Southwest Region, Sacramento, California. v + 69pp.
  39. U.S. Fish and Wildlife Service (USFWS). 2021. 5-year review California tiger salamander Sonoma County Distinct Population Segment (<i>Ambystoma californiense</i>). Federal Register 85: 4692-4694.
  40. U.S. Fish and Wildlife Service (USFWS). 2022. California Tiger Salamander (<i>Ambystoma californiense</i>) Santa Barbara County Distinct Population Segment 5-Year Review: Evaluation and Summary.
  41. U.S. Fish and Wildlife Service (USFWS). 2023. 5-year review California tiger salamander Central California Distinct Population Segment (<i>Ambystoma californiense</i>).
  42. U.S. Fish and Wildlife Service (USFWS). 21 September 2000. Final rule to list the Santa Barbara County distinct population of the California tiger salamander as endangered. Federal Register 65(184):57242-57264.
  43. U.S. Fish and Wildlife Service (USFWS). 22 July 2002. Listing the Sonoma County distinct population segment of the California tiger salamander as endangered. Federal Register 67(140):47726-47740.
  44. U.S. Fish and Wildlife Service (USFWS). 22 July 2002. Listing the Sonoma County distinct population segment of the California tiger salamander as endangered. Federal Register 67(140):47758-47760.
  45. U.S. Fish and Wildlife Service (USFWS). 4 August 2004. Determination of threatened status for the California tiger salamander; and special rule exemption for existing routine ranching activities; final rule. Federal Register 69(149):47212-47248.