Sauromalus ater is a large, flat-bodied lizard with a large rounded belly, and a wide-based blunt-tipped tail. The neck and sides of the body are covered with loose folds of skin. Their scales are small and granular. They are the second largest lizard native to the United States.

Sauromalus ater coloration can vary greatly from locale to locale. In most adult males, the head, shoulder, and pelvic regions are black while the mid-body can range from red, orange, cream, white, black, brown with varying amounts of speckling.

  • Scientific name : Sauromalus ater
  • Distribution : Nevada, California, Arizona, Utah, Mexico
  • Average Size : 0.40 m (1.3 ft)
  • Life Span : 15 years or more
  • Difficulty : Intermediate


Since Sauromalus ater are active lizards, they require spacious cages. For 1 adult chuckwalla, we recommend a cage with at least 1.4 square meters (4.5 square feet) of floor space. If using a glass aquarium, the minimum size for 1 adult is a 40 gallon breeder (0.9 x 0.45 meters (3 x 1.5 feet)) though larger is ideal. A pair of adults can be housed in a 75 gallon aquarium (1.2 x 0.45 meters (4 x 1.5 feet)) though larger being better if you can provide it. Adult males are territorial, so only one male per cage is recommended. Some babies may be raised in a small group, but close attention should be paid to ensure that all are eating well and growing at close to the same rate. Animals should be removed from the group if they are overly aggressive or overly passive. An overly passive animal may be intimidated by all other animals in the cage, and will not thrive in a group setting.
The minimum size we would recommend for 1 or 2 babies would be a 20 gallon long (0.3 x 0.75 meters (1 x 2.5 feet)). If such an aquarium is selected, keep in mind that the babies will likely outgrow this small cage in less than 6 months. We use 50 gallon plastic storage tubs made of opaque plastic.
Sauromalus ater are active lizards and thrive in larger cages. The more space you can give them, the better. We do not recommend letting them roam free in the house or yard, as they can easily escape or find a way to get into trouble.

Hide box

Rocks make the best basking sites and hiding spots. We use and recommend real rocks for chuckwalla cages. Minimally, we will use one rock for basking and a few rocks for hide spots. The basking rock(s) can just be a large chunk of rock, or a stack of flat rocks, as long as it is an elevated spot. We use flat sandstone/ flagstone for hiding spots. We use aquarium silicone to adhere “legs” to each of the pieces of flagstone, so that each piece is like a little table. The supports do not need to be more than 0.02 – 0.03 meters (0.8 – 0.125 feet) long, at the longest. Using aquarium silicone will reduce the risk of a lizard being crushed by a rock which has shifted off of its legs. These “tables” are then stacked one on top of another. This will give the chuckwallas their preferred hide spots; rock cracks. Also, any rock placed in the tank should be placed directly on the cage bottom, so that lizards will not be able to dig under them. Chuckwallas can also be crushed this way.


There are currently 2 substrates that we use in our cages; chopped straw/ timothy hay and play sand. With either option we use a thin layer evenly along the bottom of the cage. We do not recommend calcium and / or vitamin sand. The chopped straw is a good option because it is light weight and more easily disposed of as compared to sand. Our nesting areas/ humid hides have sand in them to help hold humidity. During the first year, we keep baby Chuckwallas on timothy hay substrate or kraft paper. After that if you want to switch to sand they can be. The substrate should be spot cleaned every day if possible, removing any feces, urates, and uneaten food.

Lighting – Heating

As chuckwallas are diurnal (active during the day), lighting is extremely important. We put our lights on electric timers, and give the lizards about 10 to 12 hours of light each day. We use halogen flood bulbs as the heat lights on our cages. These should be placed above the basking rock and aimed at the highest point of the rock when possible.
Basking temperatures in our cages range from 43 ºC (110 ºF) to about 55 ºC (130 ºF) on the basking surface. Babies should have a basking site on the cooler end of this range. We have observed wild chuckwallas basking when the rock temperatures are in excess of 49 ºC (120 ºF). The cooler end of the cage should be anywhere 29-31 ºC (84-88 ºF). Over this end of the cage, we place a UVB light. Good quality UVB lighting is highly recommended. We use high output (HO) T-5 fluorescent lights with at least 10.0% UVB. It is important to monitor cage temperatures multiple times throughout the year to ensure that your cage will remain a good environment for your lizard(s) as the seasons change.


Most of the water they need is received from eating the fresh vegetables. Gravid females, females that recently laid eggs and babies have a higher need for additional water, and should get a dish or have water dripped onto a flat rock in their cage 2-3 times a week. It is important to ensure that the cage substrate does not become wet or damp for extended periods of time. This can lead to a buildup of fungus or harmful bacteria in the cage. So don’t drip excessive amounts of water into the cage. Standing water in a shallow dish can be offered to adults once or twice a week.


Relatively low (15%-65%) ideally, though they will tolerate higher humidity at times. In a desert terrarium humidity can be difficult to acquire and maintain, but offering a slightly humid hide would be one option.


Chuckwallas are mainly herbivores, though they may eat some insects occasionally. In the wild they eat every day, so in captivity fresh food should be available every day as well. We feed our chuckwallas a diet that is composed mainly of dark leafy greens like kale, collard greens, chard, mustard greens, escarole, curly endive and dandelion greens. Parsley and cilantro are also used occasionally. We chop or shred the greens into pieces small enough for the lizards to swallow without having to tear the leaves too much themselves as they tend to eat more if it is easier for them to just sit and eat.
Sometimes we mix finely ground Zoo Med brand grassland tortoise pellet food and mix it into the somewhat damp greens at least a few hours before the greens are to be used. This gives the ground tortoise food enough time to become slightly moist. We use about ¼ cup of the ground pellets for each bundle of greens, and mix well. Zoo Med brand grassland tortoise pellet food is primarily made of grasses, and other raw plant matter. As the Zoo Med brand tortoise pellets are largely composed of raw, high fiber plant matter, they are a great source of dietary fiber. This is part of our effort to make our captive diet closer to what wild chuckwallas would get (high fiber, low water content). We have noticed several benefits to adding this source of fiber to their diet. We also offer 2 types of dry commercial food pellets, Rep-Cal Juvenile Iguana food and Mazuri Herbivorous Reptile LS Diet-Small. Seeds such as millet and lentils can be offered.
Two to three times a week we  add some (thawed) frozen vegetables (any combination of peas, green beans, carrots and rarely lima beans, and corn) onto the greens. Finely shredded squash, such as : acorn, spaghetti, yellow or butternut can also be offered occasionally as can finely shredded carrot sweet potato or parnsips  This diet has worked well for us, and it has kept our lizards fat and happy.
We use and strongly recommend Sticky Tongue Farms brand Miner-All (make sure that you use the indoor formula). We also use Repashy supplements like SuperPig, SuperVeggie, and SuperVite. These are used in rotation a few times a week. We also supplement their food with bee pollen, especially in the spring. A calcium supplement without D3 should only be used on animals housed outdoors.
Babies get the same leafy greens as the adults, but they are chopped up into much finer pieces. To reduce the risk of impaction, babies don’t get the frozen/thawed veggies until they are between 6-12 months old, then they are gradually worked into the diet.


Most captive chuckwallas will become tame with regular, gentle handling. Hand feeding, and allowing animals to climb on your hands is a good way to start the taming process.


Many captives will have somewhat runny feces. These can accumulate on the scales on the under side of the tail and legs. Chuckwallas should be soaked monthly, and cleaned with a soft bristled brush such as a toothbrush to remove the stuck on feces. Spot cleaning the cage daily to weekly is best as feces will accumulate quickly. And we recommend replacing their substrate and scrubbing down the cage completely every 4-6 months.


Common chuckwallas tend to shed in patches, usually taking several weeks to completely shed (sometimes longer). Juveniles shed much more frequently than adults.

Potential Health Problems

Without direct contact to unfiltered natural sunlight for most of the day, chuckwallas do not absorb enough calcium from their food. This can lead to one of the most common ailments for captive lizards; Metabolic Bone Disease. When lizards don’t get enough calcium, their bones start to degrade. This can cause loss of appetite, lethargy, debilitation, and death. Usually by the time symptoms appear, the condition has advanced to a point where the lizard will suffer permanent damage, if it even survives. This is why it is important to add calcium with D3 to their food at least 3-4 times a week and use a good quality UVB light.


Innovative Ectotherms

The information contained in this care sheet reflect the opinions and methods of the mentioned breeder, based on their expertise and long-established experience.