Chuckwalla

Description:

This species is represented by a large number of viable occurrences throughout the majority of the range in California, Arizona, and Sonora, Mexico. Abundance information is not available rangewide, but the total adult population size is probably more than 100,000. Coombs (1977) estimated a population size of 10,000-15,000 individuals in Washington County, Utah. The abundance in the remainder of the Utah range (Kane, Garfield, and San Juan counties) is likely to be less than in Washington County (G. Oliver pers. comm. 1998). Populations may vary with environmental conditions. According to Abts (1987), annual densities are variable with higher densities after relatively mild winters and the occurrence of summer rainfall. During a seven-year study in the Colorado Desert of southwestern California, densities ranged from 15 to 30 individuals per hectare (Abts 1987). Nevertheless, the area of occupancy and population size appear to be relatively stable over most of the range.

Habitat:

This lizard inhabits rocky desert; lava flows, hillsides, and outcrops. Creosote bush occurs throughout most of the range (Stebbins 2003). Habitats encompass subtropical thornforest in the southern part of the range. Individuals seek shelter in rock crevices (or in burrows on islands in the Gulf of California; Grismer 2002). Eggs are laid underground.

Notes:

Common chuckwalla in an outdoor exhibit at the Santa Barbara Zoo.