California Reptiles & Amphibians

Uta stansburiana - Common Side-blotched Lizard

Click on a picture for a larger view

Range in California: Red

Adult female, San Bernardino County

Adult male, San Bernardino County

Adult male (top) and female (bottom)
San Benito County

Adult male, San Benito County

Adult male, San Diego County

Adult Male, Inyo County

Adult male, San Diego County

Adult male, San Luis Obispo County

Adult male, San Diego County

Adult male, San Luis Obispo County

Adult male, western Riverside County

Adult, western Kern County

Adult female, western Riverside County

Adult male, Santa Cruz Island, Santa Barbara County

Adult male showing the characteristic black blotch on side and a colored throat, Alameda County

Adult male, Santa Barbara County
© Jen Castle

Adult female, Kern County

Adult male, Los Angeles County

Adult male, San Bernardino County
© Guntram Deichsel

Adult female, San Bernardino County
© Guntram Deichsel

Adult male, Yuma County, Arizona

Mating adults, Los Angeles County
© Emily Chebul

Mating adults, Kern County
© John Sullivan

Mating adults, San Bernardino County
© Jeremiah Easter

Side-blotched lizards are low on the food chain, falling prey to many predators, including desert scorpions.
© Todd Battey

Habitat, Mohave Desert, San Bernardino County

Habitat, Alameda County grassland

Habitat, coastal Riverside County

Habitat, Modoc County sagebrush desert

Habitat, San Diego County desert canyon

Habitat, Inyo County high desert

Habitat, San Diego County desert

Habitat, San Gabriel mountains chaparral, Los Angeles County

Habitat, beach driftwood on Santa Cruz Island, Santa Barbara County

Habitat, sagebrush desert, Inyo County

Habitat, Carrizo Plain, San Luis Obispo County

Chaparral/sandy wash habitat
San Benito County

Short Videos

A male side-blotched lizard tries to pursuade a female, chasing her and displaying. She is not interested, so she runs off the rock.

Common Side-blotched lizards bask on rocks, do territorial push-ups and move around in the desert.

Walking through the deserts we discover several of these common lizards basking in the sun.

Side-blotched Lizards from the sagebrush desert of northern Inyo County.

Description

Size

1.5 - 2.5 inches long from snout to vent (3.8 - 6.3 cm). (Stebbins 2003)

Appearance

A small brownish gray lizard with small smooth granular scales on the back, larger scales on the head and limbs, a gular fold, a long thin tail and a dark blue-black mark on the sides of the chest behind the front limbs. This mark may be faint or absent.

Color is brown, gray, yellowish, or black, with dark blotches, spots, and sometimes stripes. Often there is a double row of dark spots or wedges on the back, edged with white on the rear. The underside is whitish to gray and mostly unmarked. The throat is mottled with dark and light.

Males are more colorful than females, having blue speckles on the upper surfaces, which are most visible during the light phase. Northern lizards sometimes develop orange on the throat and belly. Males also have a swollen tail base and enlarged postanals, but no distinct blue coloring on the belly (which can be found on male lizards of many other species.) The throat is marked with blue, orange, or yellow.

Females are blotched on top with brown and white, often with stripes, and have a less well-defined blotch on the sides. They have no blue speckling, and no color on the throat.

Behavior and Natural History

The most abundant and commonly-seen lizard in the deserts and semi-arid areas. Diurnal. Usually the first lizard species out in the morning due to its small size which allows it to warm up quickly. It is active mostly on the ground, but a good climber. Often seen basking on rocks, hopping from boulder to boulder, or running quickly along the ground.

Active all year in the southern deserts and semi-arid regions whenever the temperature is warm. Inactive during cold weather. Males use a push-up display to display their territory. Often this lizard can be approached closely, but when frightened it runs quickly into a burrow, under a surface object, or under vegetation. The tail is often broken off when a lizard is captured, but it will grow back with time. This lizard is short-lived, living only about one year.

Some fascinating discoveries have been made recently that show cooperative behavior with this species. Males have blue, orange, and yellow color morphs. The orange males are aggressive and territorial and mate with many different females. Yellow males do not defend territories, they sneak past territorial males to mate. Blue males guard their mates, chasing off the yellow males, but they are run off when confronted by orange males. Blue males also cooperate with neighboring blue males to protect their respective mates from the orange and yellow males, and their breeding is much more successful when they do so. You can read more about Male Uta cooperation and throat colors here.

Diet

Eats small invertebrates such as beetles, grasshoppers, ants, spiders, scorpions and ticks.

Reproduction

Mates mostly in the spring. 1 - 7 clutches of 1 - 8 eggs are laid from March to August. (Stebbins 2003) Females store sperm to fertilize eggs at a later time. Juveniles hatch from June to September, and breed the following spring.

Range

In California, this species is found throughout the southern deserts and coastal region, north through the central valley and coast ranges to just south of the Bay Area, extending northward to the Sacramento River, and also north, east of the Sierra Nevada and again in the far northeastern corner of the state, and on Santa Cruz, Anacapa, San Clemente, and Catalina Ialands.

Its range outside California continues into Oregon, central Washington, southwest Idaho, Nevada, Utah, western Colorado, Arizona, New Mexico, west Texas, extreme southwest Oklahoma, Baja California, including many Pacific and Gulf islands, and into Sonora and several other states in northcentral Mexico.

Habitat

Prefers open rocky areas with scattered vegetation, including the edges of sandy washes. Utilizes a wide variety of habitats, including hardpan, sandy, rocky, and loamy areas grown with chaparral, scattered trees, grass, shrubs, and cactus.
From below sea level to around 9,000 ft. (2,700 m). (Stebbins 2003)

Taxonomic Notes

The taxonomy of this widespread and variable species has been disputed for years. Traditionally three subspecies of Uta are said to occur in California, but many experts do not recognize any subspecies pending further studies that will provide more clarification about this species (or species).

U. s. elegans -
Western Side-blotched Lizard

U. s. stansburiana -
Northern Side-blotched Lizard

U. s. nevadensis -
Nevada Side-blotched Lizard

Since I cannot find a definitive description or map of the distribution of these subspecies in California, and since research is underway that will soon re-define Uta taxonomy, all forms of Uta that occur in California are consolidated here on one page.

Conservation Issues (Conservation Status)

None.

Taxonomy
Family	Phrynosomatidae	Zebra-tailed, Earless, Fringe-toed, Spiny, Tree, Side-blotched, and Horned Lizards
Genus	Uta	Side-blotched Lizards
Species	stansburiana	Common side-blotched lizard
Original Description
Uta stansburiana - Baird and Girard, 1852 - Proc. Acad. Nat. Sci. Philadelphia, Vol. 6, p. 69 from Original Description Citations for the Reptiles and Amphibians of North America © Ellin Beltz
Meaning of the Scientific Name
Uta - state of Utah - refers to the region where it was first discovered. stansburiana - honors Stansbury, Howard S. from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz
Alternate Names
None
Related or Similar California Lizards
Urosaurus nigricaudus - Baja California Brush Lizard Sceloporus occidentalis - Western Fence Lizard
More Information and References
Natureserve Explorer California Dept. of Fish and Game Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003. Behler, John L., & F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992. Smith, Hobart M. Handbook of Lizards, Lizards of the United States and of Canada. Cornell University Press, 1946. Lemm, Jeffrey. Field Guide to Amphibians and Reptiles of the San Diego Region (California Natural History Guides). University of California Press, 2006. Brown et. al. Reptiles of Washington and Oregon. Seattle Audubon Society,1995. St. John, Alan D. Reptiles of the Northwest: Alaska to California; Rockies to the Coast. Lone Pine Publishing, 2002.

Conservation Status
The following status listings come from the Special Animals List which is published several times each year by the California Department of Fish and Game. This animal is not included on the Special Animals List, which indicates that there are no significant conservation concerns for it in California.
Organization	Status Listing
U.S. Endangered Species Act (ESA)
California Endangered Species Act (CESA)
California Department of Fish and Game
Bureau of Land Management
USDA Forest Service
Natureserve Global Conservation Status Ranks
World Conservation Union - IUCN Red List

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