Tuesday

Western Chuckwalla (Sauromalus obesus)

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Back on 02/09/2012, on a trip to Grapevine Canyon with the rock-hounds from Henderson’s Heritage Park Senior Facility, one of the members of our group spotted this Common Chuckwalla about 30 feet up on rocky ledge just above some ancient Petroglyphs.
 
Description: There are five chuckwalla species, including the common chuckwalla, Sauromalus obesus; this species, in turn, has four different subspecies, including the Western Chuckwalla. The Western Chuckwalla, is a species of lizard in the family Iguanidae. It mostly inhabits the Sonoran and Mojave Deserts of the southwestern United States and northwestern Mexico; its range extends from Eastern California, Utah, and Nevada south to Baja California and Sonora. The chuckwalla, a large (up to 16 or more inches) lizard is related to the iguana. They are pot-bellied and baggy, with loose folds of skin around the neck and shoulders and have thick tails that taper to a blunt tip. Their body color is generally dark, however the western chuckwalla usually has a light-tipped tail. Young chuckwallas have light-colored cross bands; only females retain these bands into adulthood. (click the pictures to enlarge)  In addition, Chuckwallas can change colors in response to environmental conditions. Western chuckwallas are active during the day; basking in the morning to warm up before they start searching for food. A herbivore, the chuckwalla feeds mostly on an array of leaves, buds, flowers and fruits, leaves of creosote and to a lesser extent, on other perennials and annuals. They are big and they look mean, yet are harmless to humans. When threatened, a chuckwalla will race into a crevice, take a deep breath and inflate its body, making it difficult for a predator to extract them. Its enemies are the Red-tailed Hawk, American Kestrel, Coyote and Mojave Rattlesnake. Chuckwallas are diurnal animals and as they are exothermic, they spend much of their mornings and winter days basking. These lizards are well adapted to desert conditions and are active in temperatures exceeding 102°F. When they're not breeding, basking or foraging, western chuckwallas spend a lot of time hanging out in rocky crevices. They often become inactive for weeks or months at a time during the summer (a process known as aestivation) and winter (a process known as brumation -- similar to hibernation but with periods of wakefulness). The name chuckwalla (or chuckawalla) is derived from the Shoshone word "tcaxxwal" or "caxwal," the form used by the Cahuilla Indians of southeastern California and originally written in Spanish as "chacahuala."
  
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