San Esteban Chuckwalla
Sauromalus varius (Dickerson, 1919)
Range: San Esteban Island (Gulf of California)
Diet: Leaves, Fruits, Flowers
Social Grouping: Males form hierarchies and harems
Reproduction: Mating season is April through June. Up to 16 eggs laid between June through August; eggs hatch around September.
Lifespan: 25 Years
Conservation Status: CITES Appendix I
- Largest of the five chuckwalla species, an example of island gigantism. Body length up to 60 centimeters, total length up to 75 centimeters. Body weight up to 2 kilograms. Males tend to be larger than females
- Skin color is gray with yellow or tan patches, with a darker face. Females are duller than males with fewer patches
- When threatened, the chuckwalla will run into a rock crevice and inflate its body to make it more difficult to extract; they will also wedge themselves in with their tail and claws
- Males are territorial, displaying dominance over other males by head-bobbing and doing push-ups atop rock heaps. Territories are marked using scent glands on the legs. Males become more territorial during times of plenty, less so during times of scarcity
- Gain all of their water from the plants they eat; don't urinate, excrete salty crystals instead
- Name "Chuckwalla" comes from the Shoshone name for the animal. The Latin name translates to "Flat Lizard with Speckling"
- Locally common, but considered endangered due to its very limited geographic range. In the language of the Seri people, San Esteban is called the "Island of the Giant Chuckwalla"
- The Seri translocated these lizards to several others islands as a food source (sometimes crossbred with other chuckwalla species); none of these populations have survived to the present that
- Threatened by the introduction of invasive predators and competitors, as well as over-collection for the pet trade. Sometimes killed by humans who mistake them for Gila monsters