Scientific Facts
| Common Name: | Chuckwalla |
| Scientific Name: | Sauromalus ater |
| Life Span: | Around 25 years (in captivity) |
| Size: | Approximately 20 inches |
| Habitat: | Deserts with boulders and rocks |
| Country of Origin: | Northern Mexico and the Southwestern United States |
Physical Description
Chuckwallas are big lizards which are more common in arid areas of Northern Mexico and the Southwestern United States. Some lizards that fall in this kind exist in the coastal islands. All those 6 species of chuckwallas are part of the genus Sauromalus under the iguanid family known as Iguanidae.
Chuckwallas have a stocky build. Their sagging bellies touch the ground. Also, they have scaly, thick tails. Also, their tails have a wide base and a blunt tip. These hefty lizards look overweight as they have folds of skin which hang over their neck and even on their sides.
What’s pretty interesting about chuckwallas is they exist in different colors, which may depend on their habitat. Some of them appear muddy brown while others are gray.
Male lizards have light gray with yellow, orange, or red colors, depending on the area with a black chest, limbs, and head. The tail is light yellow. Also, the male chuckwallas have femoral pores on the internal thigh that release discharges to mark regions.
Females seem to be not as colorful as the males. They also retain the banding of the baby chuckwallas.
These lizards can also have colored spots that can be in yellow, red, pink, or orange. These beautiful color patterns help them hide against the predators. The tails of young chuckwallas seem banded with yellow and black.
Extant Species
| Common Name | Scientific Name | Distribution |
| Common Chuckwalla | Sauromalus ater | Utah, Arizona, Eastern California, Nevada South to Baja California and Sonora |
| peninsular chuckwalla | Sauromalus australis | southeastern Baja California and eastern Baja California Sur in Mexico |
| Angel Island chuckwalla | Sauromalus hispidus | Isla Ángel de la Guarda, smaller islands in the Californian Gulf |
| Santa Catalina chuckwalla / Spotted chuckwalla | Sauromalus klauberi | Baja California |
| Monserrat chuckwalla | Sauromalus slevini | Islands in the Sea of Cortés, Isla Coronados, Isla Monserrate, and Isla del Carmen |
| piebald chuckwalla or pinto chuckwalla | Sauromalus varius | Rampant to San Esteban Island in the Californian Gulf |
Habitat and Range
Most species of chuckwallas live primarily in Northern Mexico and Southwestern states. The common chuckwallas live in the deserts within the southwest, mainly in Arizona. They are natives to the Sonoran Desert in Arizona and the Mohave Desert in California. Also, they can be seen at the Lake Powell region, Grand Canyon, and desert regions alongside the Colorado River.
They typically hide beside the piles of rocks and on the canyon outcroppings and walls, giving them easy access to crevices and cracks when threatened. Chuckwallas inflate themselves until they are securely and tightly wedged into the crevices. This will keep them safe from the primary predators.
Life Span
Common chuckwallas usually live for 10 years and more. When captivated, they can live for up to 25 years or even longer. Their lifespan depends on the growing conditions, sufficient food supply, and limited predation.
Their average lifespan in the woods is around 15 years. Though there’s considerable variability every year, on average, the 1st year survivorship is approximately 38%. Egg mortality triggers a huge effect on survivorship under 1 year old.
Those lizards that survived the first year of their lives will have a survival rate of 75% every year. There have been stories of chuckwallas that lived for more than 25 years. One of them was 30 years old while the other lived for up to 65 years.
Ecosystem Roles
Chuckwallas are herbivores. They eat plants and sometimes, insects. Through plant and fecal deposits clearing, they affect diversity within their habitats. People use them as hosts for multiple mite species including other parasites, such as:
- Mites (Hirstiella trombidiiformis)
- Mites (Hirstiella pyriformis)
- Saurian malarial parasites (Plasmodium mexicanum)
Predation
Chuckwallas are good at detecting and evading their predators. Their key adaptation is hiding into the rocks and crevices whenever they feel scared or threatened. Rocks serve as their biggest defense. When there’s a threat, these lizards will rush into the crevice, gulp air to inflate their bodies and wedge themselves into the rocks. Therefore, the predators will struggle to get them out of the crevice.
Chuckwallas love basking, too. While doing it, they flatten their bodies against the rock, exposing well their bodies to the sunshine. This way, their bodies will absorb more heat.
Chuckwallas are also great in hiding themselves from the predators. Their camouflaging ability makes it hard for the predators to distinguish them and their shadows. They use their neutral-colored scales to cover up themselves.
Crevices and tight holes between the rocks are inaccessible to bigger predators. They provide a defensive benefit against the larger birds and mammals. However, reptiles like the snakes can fit into them. Their predators include birds, coyotes, and red-tailed hawks.
Even humans became their greatest predator in the past. The native Americans used to catch and kill them for food. These people used a specially designed device crafted using stick and stone in pulling them out of the crevices in the rocks.
Despite that, chuckwallas remain huge in numbers. The IUCN or International Union for the Conservation of Nature included chuckwallas in the list of the least vulnerable animals on the planet.
Behavior
Chuckwallas are extremely territorial, specifically the males. They excrete scent through their glands that helps them mark their territory. The males tolerate females which overlay their home range, but they don’t do it to other male chuckwallas.
These big lizards hibernate from October and will last until February. The hibernation period for chuckwallas differs from region to region. They prepare themselves for this period by slowing their body functions and metabolism so that they can endure the adverse effects of colder temperatures.
Chuckwallas are harmless and nonpoisonous lizards as they don’t have those glands that produce venom. They rarely show anger, which happens only when they feel threatened and uncomfortable. Chuckwallas may bite which can be slightly painful. If your pet bites you, just clean it and use your first-aid kit.
Hibernation
As winter begins and temperatures drop down while food sources reduced, the reptiles living in the desert including chuckwallas will head into the hibernaculum to bromate or hibernate for the whole season.
Hibernation usually takes place after foraging. It’s more serious than sleep. Most of the reptiles living in the desert such as rattlesnakes and chuckwallas undergo this period. Hibernation dramatically decreases energy output so that it will be easier for these animals to survive the winter season.
The extreme heat outdoors can be deadly for them. The same is the case during the snowy time. Therefore, care should be taken when changing the environment for the lizards for the brumation or hibernation period.
In general, the desert lizards, especially the chuckwallas can endure temperatures dropping to 50 and 55 degrees Fahrenheit or 10 to 12 degrees Celsius. When the room air temperature of the enclosure falls under this temperature range, supplemental heating will be necessary to help keep the temperature within the ideal range. Hibernation begins wherever in November and might last through February or March.
To make sure that your pets do not enter the hibernation period while their digestive tract is not yet clear, don’t allow your pets to enter the process after consuming the usual amount of food you’re giving them. Their guts should not be full throughout the winter. Their gut will slow down and stop in the end, but the process of food decomposition will take place.
You can imitate the seasonal change by lowering the hot temperatures, increasing the nighttime length, and reducing the daytime length. Do it during the late fall and early winter. Be sure to give your pets clean water at this period.
Experts are still unaware of the biological importance of hibernation or brumation for desert iguanas and chuckwallas. If they didn’t undergo the process when they have to, this could be detrimental to their health. It may lead them to sickness or death.
Changes will be noticeable as your chuckwallas begin to prepare themselves for hibernation. Usually, they become a little sluggish for some days, which is due to slowing metabolism. The rest of their bodies will also adjust to this change.
Awareness and Communication
Only a few information is available when it comes to awareness and communication in chuckwallas. These lizards usually spend their time alone, so there’s just minimal intraspecific communication. You may see them communicating only when the male chuckwallas compete for territory access and seduce the females for mating.
Most communication among chuckwallas is limited to courtship, mating, and territorial dispute. Males are fighting to one another. They also strongly bob their heads to impress the females. The female chuckwallas will assess the males according to their moves, jaw-rubbing, and nudging before mating.
When hunting for food, they use their lingual vomeronasal system to choose what is food and what is not. They do it by checking the chemical signals from their tongue.
Chuckwallas are blessed to have acute eyesight and the ability to move at a distance of 30 meters. However, they don’t have a good sense of hearing.
Diet
Chuckwallas are herbivores, so they consume more kinds of plants. Sometimes, they eat plants and fruits growing within their habitat. In other instance, their option is to eat insects when there are no fruits and plants available. They eat early in the morning and spend the rest of the day by exposing themselves to the sunlight.
These lizards love to eat:
- Clover
- Dandelion
- Leafy salads
- Honeysuckle
- Curly kale
- Watercress
- Spring greens
- Brussel tops
- Parsley
- Coriander
- Parsnip
- Carrot
- Rocket
- Courgetti
- Peppers
Also, they eat non-citric fruits in small amounts. Some plants they can’t eat are spinach, cabbage, buttercup, tomato, iceberg lettuce, and citric fruits. Chuckwallas feed eat once every day.
Since they live in the desert, chuckwallas get all the water from the plants they consume. The occasional water mist might induce them to drink the drops from the furniture and cage walls. In taking care of chuckwallas, give them a bowl of water.
Vitamins and Supplements
Calcium supplements are advisable for chuckwallas. You can add a calcium supplement on their foods twice or thrice a week. Do it more often when your pets are gravid or sick. Try giving different food every day for a perfect balance of vitamins and minerals for your pets’ optimal growth.
Housing
Chuckwallas are best kept in a big wooden vivarium. Wood is a great wood insulator. Thus, a wooden vivarium will help you easily control the temperatures needed inside your pets’ habitat. Other enclosures like glass terrariums are too effective at dispersing heat, making it hard to increase the temperature and keep it consistent across the year. Also, the wooden vivarium must have good ventilation which will help eliminate humidity and replenish the air within the cage.
Give your pets a large vivarium that measures at least 46 inches or 1150 mm long. The size matters for two reasons. First, chuckwallas are not little lizards as they can grow up to 450mm long. They need more space to stay happy. Second, the vivarium should be long enough to create a temperature ramp. The enclosure should be very hot in one end but cold on the opposite end.
Hide Box
Rocks are great spots for hiding and basking. Use real rocks and put them inside the cage. Provide one rock for basking and another for hiding. The basking rock can be a big chuck or stone or a pile of flat rocks. Flat flagstone or sandstone are your great choices.
You can also use aquarium silicone to attach the “legs” to each piece of flagstone. This way, every piece forms like a small table. Stack these tables on top of the other, forming a great hiding spot that your pets will enjoy.
Put the rocks directly on the bottom of the cage to prevent your pets from digging under them. Otherwise, the rocks will crush them.
Substrate
Chuckwallas need a dry substrate, which will help control the humidity within the vivarium. You can keep these lizards on the sand.
These lizards may swallow a loose substrate by accident. However, it can be prevented with proper habitat setup and diet.
Chuckwallas are not arboreal lizards. They like climbing on top of things to check their environment. Decorate your vivarium with different pieces of rock and wood so that they can do this inside the cage.
You can decorate the vivarium with synthetic plants to give it a more natural, pleasing look. You can use desert plants and add perches. Trailing plants is a good way to disguise the electric wirings and equipment while giving a perfect cover for the baby lizards.
Lighting and Heating
Don’t use heated rocks. Chuckwallas may burn themselves if they stay on these rocks. You can use polystyrene background to keep the lizards well-exercised since they like to climb.
Also, you can take them out of their cage and put them in any other enclosure for at least 15 minutes during the hotter days. This way, you’re letting them exercise. Just make sure the enclosure is free from any poisonous plants
The basking temperature can range from 43 degrees Celsius or 100 degrees Fahrenheit to around 55 degrees Celsius or 130 degrees Fahrenheit on the basking surface. Babies must have a good basking spot on the cooler side of the vivarium.
In the woods, chuckwallas enjoy basking if the rock temperatures exceed 120 degrees Fahrenheit. The colder side of the cage must be anywhere between 29 to 31 degrees Celsius or 84 to 88 degrees Fahrenheit. Through this site, you can put a UVB light. Choose UVB lighting in good quality, as high output T-5 fluorescent lights of at least 10.0 percent UVB.
Also, you should check the cage temperatures several times across the year. That’s one way to ensure that your vivarium stays as a pleasing and safe environment for the chuckwallas while the seasons are changing.
Humidity
In terms of humidity, it should stay between 15 to 65 percent. However, chuckwallas can also tolerate humidity in some cases. In the desert, terrarium humidity is tricky to obtain and preserve. A slightly damp hide, though, will be a great choice.
Handling many captive chuckwallas become tame with gentle handling. The more often you do it, the easier it will be to make these lizards disciplined. You can do hand feeding and letting them climb and walk through your hands.
Cleaning the Enclosure
Most captives would have runny feces. These may accumulate on the sales on the underside of their legs and tails. To keep them clean, soak the chuckwallas and clean them with a toothbrush with soft bristles to remove the feces. Spot cleaning the cage on a daily or weekly basis is advisable as feces often accumulate quickly. Replace the substrate and scrub down the cage thoroughly every 4 to 6 months.
Shedding
Chuckwallas shed in patches. The process typically takes several weeks or even longer to shed completely. Young chuckwallas shed more often compared to adults.
Possible Health Problems
Without direct contact with the natural sunlight for the rest of the day, chuckwallas fail to absorb the calcium from the provided food or supplements. It can result in a condition called Metabolic Bone Disease.
Metabolic Bone Disease is a common disease among pet reptiles. This condition is not as simple as calcium deficiency. The primary concern here is the interruption of calcium metabolism that triggers a host of relevant issues.
MBD is the outcome of poor husbandry. You can prevent it by giving the right diet and environment for your chuckwallas.
The following are the possible causes of Metabolic Bone Disease:
- Inadequate protein
- Liver or kidney disease
- Small intestinal illness
- Lack of exposure to UVA and UVB, which are crucial for the natural production of vitamin D
- Vitamin D deficiency
- Less calcium or excessive phosphorus in the food
- Presence of those substances in the food that can affect the absorption process for calcium
- Insufficient protein
- Diseases affecting the parathyroid or thyroid glands
- Living in colder temperatures that impairs digestion and harm calcium absorption
If you suspect your pets have MBD, watch out for these symptoms:
- Swollen or bowed legs and bumps on the long leg bones
- Curved spine or bumps along with the spinal bones
- Softened and swollen jaw (also known as “rubber jaw”)
- Retroceded lower jaw
- Muscle tremors with jerky moves or twitching in the leg muscles
- Limping and lameness
- The reptile is not eating
- Obstipation or constipation
- Lethargy
- Bone fractures caused by the weakening of the bones
- Weakness and partial paralysis (the animal struggles to lift its body off the ground due to weakness)
MBD is quite distinctive as the diagnosis usually depends on the physical exam, symptoms, and talking about husbandry. Radiographs or x-rays can be taken to verify the diagnosis, track treatment, and check the calcium level in the blood.
The treatment for metabolic bone disease depends on the disease and its severity. For the mild cases, switching to a well-balanced diet and correct husbandry might be enough. Serious cases need intensive vitamin and calcium supplementation combined with increased exposure to high-intensity UVB lighting under the care of a reptile specialist.
Prevention
Proper husbandry includes not only giving chuckwallas a well-balanced diet. These things are crucial for both the treatment and prevention of MBD:
- A balanced diet. It has to be rich in phosphorus, calcium, energy, protein, and other nutrients.
- Exposure to UVA or UVB light rays
- Correct light and dark cycles
- Ideal heat gradients
- Adequate enclosure or enough room for climbing and exercising
Breeding
When it comes to mating and reproduction, the male chuckwallas attract the females either with their persistence or size. Typically, a territory has one male and three or more females. The male mates with all those female chuckwallas in the territory. The male chuckwallas entice the females to mate by using different methods like head-bobbing, circling, licking, nudging, and jaw-rubbing.
Females will allow mating if they like the male lizard. The animal might assert themselves when they’re big and forceful. When they mate, the male chuckwallas use their jaws in grasping the females through the loose skin at the back of their neck.
The mating process among chuckwallas occurs mostly in the early spring following the hibernation process. Both male and female chuckwallas have two more partners every year. Males compete for females by head-knocking and biting.
The breeding season for chuckwallas often lasts between April and August – when food is available. When the females are interested, their ovaries enlarge. The male chuckwallas produce sperm every year while the females produce eggs every other year, in most cases.
The male chuckwallas will be sexually mature when reaching a 125 m nose-vent length or around 2 years old. The female chuckwallas will be sexually mature once they reach the same length, but they take 2 or 3 years to grow and reach the ideal length.
On the other hand, females attract the male lizards with their stronger scent produced by their glands that spread across their bodies. Typically, chuckwallas mate from April until July. Males sometimes fight with females to win a chance for mating.
When mating is over, the female chuckwallas will start searching for a perfect place for making a nest. The gravid females must gain easy access to the nesting box where she can lay her eggs. The box must be big enough that she could turn around within the box.
Female chuckwallas need a warm spot for the effects. Also, this spot has to be safe from predators. The female lizards will deposit the eggs in the nest at the end of August. They will stay in their nest for around 30 days.
The eggs should stay in the incubator with a temperature of 84 degrees Fahrenheit. After the next 60 days, the eggs should start hatching and the babies will emerge and provoke the other eggs to hatch.
The young chuckwallas should be able to manage themselves on their right after the eggs hatched. Their mothers won’t be there to take care of them after laying the eggs. Every female chuckwalla can lay 5 to 16 eggs.
Distribution
Chuckwallas originate mostly in the arid regions of the US. However, some of them exist in the Northern part of Mexico. Majority of the chuckwallas live in the Mojave Desert. They exist in warmer areas like Arizona, California, Nevada, and Utah. This lizard enjoys those rocky areas where they can easily find shelter and even food. Also, they use those rocks as a location for their basking habit.
Conservation
The population of chuckwallas is safe under the supervision of the natural parks. Also, these lizards are naturally secured because their habitat is mostly in remote areas with rugged terrain or harsh climate conditions. The trends towards improving the deserts of the US and Mexico affect their habitat. However, the population of chuckwallas in these areas remains huge and stable.
The Positive Effect on Humans
Chuckwallas may not be naturally friendly to humans, but any experienced lizard owner can easily turn them into pets. As of now, Nevada is the sole American state in which collecting chuckwallas as commercial pets is legal mainly due to their stable and large population in the area.
The Negative Effect on Humans
Chuckwallas cannot harm humans. They are independent animals which are easy to scare and intimidate. They are hard to find. Also, they do not cause disturbances to people.
Taking care of them as a pet is never a bad idea. Chuckwallas are nonpoisonous animals. They may bite humans for some reasons like fear and aggression. The good thing is their bite can’t cause harm for as long as you treat it well. The bite may be sore but not to the unbearable point.
Where to Get One?
You can buy a couple of chuckwallas from a reliable pet store, particularly the one selling reptiles like snakes and a wide array of lizards. You may get your new pets locally, but there are choices as well to get them from online sources.
How to Care for a Chuckwalla?
Taking care of and treating chuckwallas as pets like dogs and cats seem to be daunting at first. However, that is always possible by knowing the proper way to feed and handle them.
For chuckwallas, the care level is within the intermediate level. You just need to fulfill the needs of your pets. Give them enough food, a good shelter filled with the necessary accessories, and nutritional supplements. Aside from that, you need to maintain the humidity level and temperature within the enclosure.
Likewise, you need to give the UVB bulbs to form the artificial lighting that you can turn off at night. Also, you can decrease the temperature in the enclosure. When buying an enclosure for your chuckwallas, make sure the enclosure is right for the size of your pets.
Fun Facts about Chuckwalla
- Chuckwallas sneeze salt. With their salty plant food, these big lizards have those special glands responsible for harvesting excess salt. These glands sit behind their nose. They sneeze to get rid of the buildup.
- When they hatch, the baby chuckwallas stay in their eggshells for 24 hours before they crawl out and explore the environment.
- Just like other lizards, the tails of chuckwallas will regrow in case they get damaged.
- The name “Chuckwalla” came from the Shoshone term “caxwal” or “tcaxxwal”.
- Chuckwallas can grow up to 16 inches long and weigh 2 pounds. Males are bigger than females.
- These lizards can change the color of their skin and blend into the surroundings when feeling threatened.
- Chuckwallas are not nocturnal animals. They spend most of their time under the sun. They remain active throughout the day.
- Chuckwallas depend on the sun in keeping themselves strong. For them, basking will help them get an extra boost to their energy.
FAQ
What do baby chuckwallas eat?
The baby chuckwallas enjoy eating dandelion flowers. As they grow up, they will start looking for new tastes, so they eat other flowers, fruits, desert plants, and even the insects in their territories.
Are chuckwallas harmful to humans?
Chuckwallas are never harmful to humans. They are nonpoisonous, so their bite is not a big deal though it can be slightly painful.
Are chuckwallas aggressive?
Chuckwallas are territorial and may become aggressive only when others try to invade their territory. When it comes to predators, including humans, they quickly try hiding in the rock crevices.
How long do chuckwallas live?
In the woods, the chuckwallas can live for up to 15 years. However, those that are grew in the care of professional breeders can live for 25 years or even longer.
What are the predators of chuckwallas?
Mammal predators like coyotes and bigger birds like red-tailed hawks are the most common predators of chuckwallas. Even the snakes may likely consider them as food.
Do the chuckwallas have the camouflaging ability?
Yes, chuckwallas have the camouflaging ability. They use their neutral-colored scales and the colored patches on their skin to blend into the environment when there’s an enemy.
Do chuckwallas eat cactus?
Chuckwallas are herbivores that can eat leaves, buds, flowers, and cactus fruit. The creosote bush seems to be the biggest part of their daily diet.
Do chuckwallas drink water?
Chuckwallas do not typically drink water because they depend on the water content of the fruits and plant they eat. However, the occasional water misting might persuade them to drink the drops from the furniture and cage walls.
How should I choose a vivarium for my chuckwallas?
In choosing a vivarium for your chuckwallas, look for one that is made of wood. Don’t forget to check the size – it should be at least 4 feet long to fit an adult chuckwalla.
Are chuckwallas endangered?
No, they are not classified as endangered species. Their population stays big and stable.
Are chuckwallas good pets?
Chuckwallas are not friendly. They may bite you as self-defense, but you can make their tame with proper and regular handling.
How do chuckwallas communicate?
Male chuckwallas communicate and protect their territory against the other males. They do push-ups, mouth gaping, and head-bobbing.
How often do chuckwallas reproduce?
Chuckwallas do not breed every year. While male chuckwallas produce sperm every year, females are ready to mate every other year.
What does the chuckwalla adaptations mean?
Adaptations mean chuckwallas should maintain increased body heat to stay active. The cold nighttime temperature makes them feel weak and vulnerable, so they spend the whole day under the sun to increase their body temperature.
