Chuckwallas (Sauromalus ater) are 15-20” long, diurnal, terrestrial lizards native to the Mojave desert of the southwestern United States and northern Mexico. They are usually found in desert habitats with plenty of rocks and crevices for hiding.

Chuckwallas are stout lizards with a large abdomen, thick tails, sturdy limbs, and baggy skin. They generally have a gray, brown, or black base color with additional cream, yellow, or orange coloration. Males are generally more colorful than females.

Chuckwallas are uncommon in the US pet trade, but if you can find one captive-bred, they generally make for fairly tame, easygoing pets. Due to their size, equipment needs, and lifespan, these are intermediate-level pet reptiles. With good care, they can live as long as 65 years!

How much space do chuckwallas need?

A single chuckwalla should be housed in no smaller than a 48” x 24” x 24” enclosure (120 gallons). However, if you can provide a larger enclosure, do it! Providing a larger enclosure will provide your pet with more opportunities to exercise, explore, and demonstrate natural behaviors.

Housing multiple chuckwallas in the same enclosure is not recommended.

Do chuckwallas need UVB?

Yes! Chuckwallas are diurnal, which means that they are most active during the day, and naturally exposed to lots of sunlight on a day-to-day basis. This means that they need UVB light as part of their enclosure. The best UVB bulbs for a chuckwalla housed in a 48” long enclosure are:

• Zoo Med Reptisun T5 HO 10.0, 22”
• Arcadia Desert 12%, 22”

Use a high-quality reflective T5 HO fixture for the bulb, such as Arcadia or Vivarium Electronics. If the UVB is mounted over mesh, place the basking area so the lizard’s back will be 8-12” below the lamp. If the UVB is mounted inside the enclosure, place the basking area so the lizard’s back will be 14-16” below the lamp.

Note that UVB is blocked by glass and plastic, so you can’t give your lizard UVB by placing its terrarium in front of an open window. Also make sure that your UVB fixture does not have a clear plastic bulb cover.

In addition to UVB, since chuckwallas are day-active lizards, it’s beneficial to provide an additional daylight-spectrum lamp to make sure the enclosure is brightly illuminated. Use a strong 6500K LED or T5 HO fluorescent plant grow light for best results.

Chuckwallas should get 10 hours of light per day during winter and 14 hours of light per day during summer. This simulates natural seasonal changes in day length and encourages healthier hormonal rhythms.

What basking temperatures do chuckwallas need?

Chuckwallas like it hot! They should have a basking surface temperature between 120-130°F, with cool side temperatures between 75-85°F. Nighttime temperatures should be between 65-75°F, which can usually be accomplished by turning off the heat source. Measure your temperatures with a digital probe thermometer with the probe placed on the desired surface. 

Provide heat for your collared lizard by imitating the sun with a couple of halogen heat lamps clustered on one side of the enclosure. Do not use ceramic heat emitters (CHEs), heat mats, red bulbs, or blue bulbs, as these are not as effective. For best results, the basking surface itself should be a large, flat piece of rock.

As part of their seasonal cycle, chuckwallas should be permitted to brumate (the reptile version of hibernation). This helps regulate their hormonal cycle, boost overall health, and is likely to increase longevity.

What humidity levels do chuckwallas need?

Chuckwallas are a truly arid species that don’t need much in the way of enclosure humidity, and too much humidity can harm them. Target average ambient humidity levels between 15-30%. However, they do benefit from access to a humid burrow. A good way to do this is to simply moisten the substrate below/inside one of their hideouts.

What substrate is good for chuckwallas?

Substrate covers the floor of your lizard’s terrarium and helps make the enclosure more attractive, but it also helps maintain desired humidity levels and provides something for your chuckwalla to dig around in.

It’s ideal to use a substrate that imitates the “substrate” that the reptile naturally lives on in the wild. For chuckwallas, that means sand or sandy soil. We recommend the following substrates for chuckwallas:

• Zoo Med ReptiSand
• Exo Terra Desert Sand
• Play sand

Substrate should be at least 4” deep and completely replaced every 3-4 months. Remove poop and urates daily, along with contaminated substrate.

What décor can you use in a chuckwalla terrarium?

A bare enclosure is a boring enclosure, and although size matters, if there’s nothing inside it, it won’t do much for your chuckwalla. Enrichment items that help simulate the reptile’s natural habitat help prevent boredom and encourage your chuckwalla to exercise natural behaviors.

At bare minimum, you will need at least one cave/burrow for the chuckwalla to hide in and a flat stone for basking on. However, it’s best to include other items, such as:

• secure stacks of flagstone or aquarium slate
• more hiding places
• ledges
• hollow logs
• branches
• live, edible plants

What do chuckwallas eat?

Chuckwallas are herbivorous, which means that they eat plants to get the nutrition that they need. Chuckwallas should be able to eat their fill of greens every day, with occasional fruit as a treat. Approximately 60% of their diet should be dark leafy greens, with 30% consisting of other vegetables. Chop vegetables into bite-sized portions to help prevent choking.

For a healthy, happy chuckwalla, offer as much dietary variety as you can! 

Leafy greens for chuckwallas: collard greens, cactus pads, spring mix, arugula, kale, alfalfa, bok choy, carrot greens, spinach, dandelion greens, hibiscus greens, turnip greens, mustard greens, parsley, romaine lettuce, escarole, watercress, clover

Other vegetables for chuckwallas: broccoli, rapini, zucchini, cauliflower, sweet potato, bell pepper, squash, carrots, okra, sprouts, pea pods, green beans, shredded carrots

Due to its high sugar content, fruit should be used as a treat. Options include berries, mango, cantaloupe, apple, banana, and papaya. Edible flowers such as dandelion and nasturtium can also be offered.

Insects can also be used as a rare treat.

Supplements

You will also need calcium and vitamin supplements to prevent your lizard from developing a deficiency. We recommend Repashy SuperVeggie, lightly dusted on all salads.

Water

Although chuckwallas are desert reptiles, they still need access to fresh water. Provide a small water bowl where your lizard can always get a drink when needed. Change the water daily and scrub the bowl with a reptile-safe disinfectant weekly, or whenever it becomes soiled.

Do chuckwallas like to be handled?

Few reptiles actually “like” to be held, but chuckwallas usually learn to tolerate it well, especially individuals that were bred in captivity. Don’t grab the lizard from above — instead, approach from the side and scoop from below. Support as much of its body as possible, especially its feet. Start with very short handling sessions in the beginning, then gradually make them longer as your pet becomes more accustomed to you. Hand-feeding via feeding tweezers is a great way to start building trust.