Please see Part I of this article for more on the natural history of North America’s second largest lizard, the Chuckwalla (Sauromalus obesus).
Status in the Wild
Population levels appear stable as their preferred habitat is largely unsuitable for development. The species S. varius, however, is limited in distribution to 3 islands in the Gulf of California and is listed on CITES Appendix I.
Mating takes place in May-June, with 5-16 eggs being laid (buried in the sand) in June-August. In the wild, females usually breed every other year, but captives may lay a clutch yearly.
Diet, Natural and Captive
Chuckwallas are largely herbivorous, consuming the leaves, buds, flowers and fruits of desert plants. Beetles, ants, caterpillars, spiders and other invertebrates are occasionally taken. In common with similar lizards, juveniles consume somewhat more invertebrate prey than do adults.
Captives fare best on a varied diet of kale, collard greens, turnip greens, bok choy, romaine, carrots, yams, peas, beans and seasonally available vegetables, along with occasional feedings of crickets, mealworms, beetles and other insects.
I’ve found dandelion flowers to be a great favorite, and usually mix some soaked Tortoise Pellets into the salad as well.
A Unique Defense
Chuckwallas spend a good deal of time basking on rocks to achieve their preferred body temperature of 100 F.
They rarely forage far from a rock pile, into which they retreat when threatened. Once secure within a crevice, the Chuckwalla gulps air and inflates its body, thereby wedging itself tightly against the rocks. Certain Native American peoples utilized the Chuckwalla as food, and extracted it from the rocks by piercing the body with a sharp stick to deflate the lungs.
I’ll cover the care of these most interesting lizards in the future.
An interesting account of a field trip to see Chuckwallas and other California herps, along with interesting photos, is posted here.
A video showing a very eager Chuckwalla feeding from the hand is posted here.
I am very interested in having a chuckwalla. Where can I find some practical info about building a cage for it? which kind of lamps and accsesories do I need?
thanks in advance for advice
Hello, Frank Indiviglio here.
Thanks for your interest in our blog. Building your own cage is the best option for a chuckwalla…they can be kept in glass aquariums, but easily contract fungal infections due to damp conditions/poor air circulation. Please check out these plans for building a Tortoise Table. This type of enclosure will work equally well for a chuckwalla. A large cage will allow you to establish a thermal gradient…in smaller terrariums, the hot basking lights required will result in ambient temperature that is too high (i.e. away from the basking site, you’ll want 75-85 F, please see below).
You’ll need to provide a basking site of 100-110 F and high UVB exposure. A mercury vapor lamp will provide heat and UVB and UVA (UVA is also valuable). A ZooMed 10.0 bulb will provide enough UVB if you can position the basking site within 6-12 inches of the bulb, but a mercury vapor is a safer choice. The ZooMed does not provide heat, so you’ll need an additional basking light as well.
Please let me know if you need any further information…we can also discuss diet and care when you are ready. Good luck, enjoy and please keep me posted.
Best regards, Frank Indiviglio.