With characteristic jerky movement, a California Whiptail forages on the slopes of a mountain in Contra Costa County.
Aspidoscelis tigris as a species is 2 3/8 - 5 inches inches long snout to vent (6 - 12.7 cm), up to around 13 inches (33 cm) total length.
A slim-bodied lizard with a long slender tail, a pointed snout, and large symmetrical head plates.
Scales on the back are small and granular, and scales on the tail are keeled.
The belly is made of large, smooth, rectangular scales in 8 lengthwise rows.
The tail can reach up to two times the length of the body.
Color and Pattern
The back and sides are gray, tan, or brown, marked with dark spots or bars or mottling, which is often very sharply defined.
Dark marks on the side don't form vertical bars.
Usually 8 faint light brown stripes are present, but stripes on the side are sometimes indistinct.
The throat is pale with with large black spots.
Often there are reddish patches on the sides of the belly.
The tail tip is dark or bluish.
The tail tip is bright blue on juveniles.
Juveniles have fairly well-defined stripes.
Life History and Behavior
Wary and very active, moving with abrupt stops and starts, side-to-side head movement, and tongue flicking.
Often seen digging rapidly when foraging.
Difficult to approach - typically foraging near cover, and capable of quick bursts of speed into heavy brush or holes.
Diet and Feeding
Small invertebrates, especially spiders, scorpions, centipedes, and termites, and small lizards.
Unlike some species of whiptails which are all females, there are male and female western whiptails.
Males and females usually begin mating in May and females lay eggs shortly thereafter.
Females lay one clutch of eggs per year.
Eggs hatch from May to August.
Hot and dry areas with sparse foliage and open areas. Found in forests, woodland, chaparral, riparian areas.
This subspecies is endemic to California, ranging throughout the Central Valley, west to the coast just north of the Monterey Bay, and south through the South Coast Range to Ventura County where there is a zone of intergradation with A. t. stejnegeri.
The species (Aspidoscelis tigris) ranges from Oregon and southern Idaho, south through California and Nevada to Baja California, and east into Utah, Colorado, Arizona, and New Mexico and south into Sonora and Sinaloa, Mexico.
(My California range map shows a question mark in the northeast corner of the state. The California Dept. of Fish and Wildlife maps show the species present in much of Shasta, Siskiyou, Modoc, and Lassen Counties. The 2003 Stebbins field guide and the 2012 Stebbins & McGinnis field guide show a question mark in the area, as I do. I have searched museum records but I have found no records for A. tigris in Siskiyou or Modoc counties.)
The species is found at sea level to 7,000 ft. (2,130 m). This subspecies may differ somewhat.
Stebbins, Robert C., and McGinnis, Samuel M. Field Guide to Amphibians and Reptiles of California: Revised Edition (California Natural History Guides) University of California Press, 2012.
Stebbins, Robert C. California Amphibians and Reptiles. The University of California Press, 1972.
Samuel M. McGinnis and Robert C. Stebbins. Peterson Field Guide to Western Reptiles & Amphibians. 4th Edition. Houghton Mifflin Harcourt Publishing Company, 2018.
Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003.
Behler, John L., and F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992.
Powell, Robert., Joseph T. Collins, and Errol D. Hooper Jr. A Key to Amphibians and Reptiles of the Continental United States and Canada. The University Press of Kansas, 1998.
Bartlett, R. D. & Patricia P. Bartlett. Guide and Reference to the Turtles and Lizards of Western North America (North of Mexico) and Hawaii. University Press of Florida, 2009.
Jones, Lawrence, Rob Lovich, editors. Lizards of the American Southwest: A Photographic Field Guide. Rio Nuevo Publishers, 2009.
Smith, Hobart M. Handbook of Lizards, Lizards of the United States and of Canada. Cornell University Press, 1946.
The following conservation status listings for this animal are taken from the November 2020 California "Special Animals List" and the November 2020 "State and Federally Listed Endangered and Threatened Animals of California" list, both of which are produced by multiple agencies and available here: https://www.wildlife.ca.gov/Data/CNDDB/Plants-and-Animals. You can check the link to see if there are more recent lists.
If no status is listed here, the animal is not included on either list. This most likely indicates that there are no serious conservation concerns for the animal. To find out more about an animal's status you can go to the NatureServe and IUCN websites to check their rankings.
This animal is not included on the Special Animals List, which indicates that there are no significant conservation concerns for it in California.