Chuckwalla Care Sheet

Natural History

The chuckwalla is a beautiful lizard found in the southwestern United States and northern Mexico. They can also be found on some coastal islands in the same region. The chuckwalla normally has a dark colouration and small, fine scales. The chuckwalla is quite wide bodied with a thick tail that runs down to a point.

The chuckwalla is mostly herbivorous and are normally only territorial around breeding time. When the chuckwalla wants to assert dominance they can modify their torso colour slightly, they will open their mouth and bob up and down.

The Mojave Desert

Housing

Chuckwalla come from a very warm and dry environment so they struggle with the colder and more humid climate in the UK and require heating and lighting to thrive. To insulate against the cold and help keep temperatures consistent we recommend keeping a chuckwalla in a wooden vivarium. Due to the temperature gradient required for this species we recommend an enclosure as close to 4 x 2 x 2ft (width x depth x height) as possible.

When selecting the vivarium, we look for an enclosure with numerous large vents and glass sliding front doors. All of this ventilation should ensure that heat is lost from one side of the enclosure to the other while keeping the basking spot itself at a consistent temperature.

Younger chuckwalla may feel exposed and frightened in large open spaces so we make sure to include a lot of decorations. These can be removed as the chuckwalla grows in size and gets used to its environment, providing more space to move around and bask within the enclosure.

Heating

In the wild, the chuckwalla will spend a lot if its time basking in the sunlight. As such they require a very warm basking area of 38-43℃(100-110℉) during the day time. We aim to provide this heat over 1/3 of the enclosure while letting the rest of the enclosure cool to room temperature on the opposite side. To achieve this, we attach a strong basking lamp to the ceiling on one end of the enclosure. This is controlled by a high temperature dimming thermostat to make sure that the temperature is kept correct and consistent throughout the day. The basking lamp is left on for 10-12 hours per day.

At night, all of the lights should go off and the enclosure should be completely dark. This will make sure that the chuckwalla has a clear day and night cycle. Though the chuckwalla will experience intense heat throughout the day time they will also experience a much cooler temperature at night. To simulate this, we would not provide any night time heating unless your room is likely to drop below 13℃ (55℉) at night.

If you would like the heating and lighting to run automatically you could use a mechanical timer with your UVB tube and basking lamp.

Though the thermostats we sell are very reliable it is always best practice to monitor your temperatures with a thermometer. A 2℃ (5℉) variance on the basking spot is nothing to worry about as long as your cool side is still cool. A simple dial thermometer on each side should be sufficient but digital probe thermometers are much more accurate.

Baby Chuckwalla
Adult Chuckwalla

UVB Lighting

As described in the previous section, a wild chuckwalla will spend a lot of its time basking. During this period, the chuckwalla is exposing itself to plenty of warmth and UVB.

To aid in deciding which intensity UVB is required for each species, UVI readings have been taken in their natural habitat. These readings are compiled over time to get an average exposure reading which sits in one of 4 distinct ranges called Ferguson zones. Zone 1 animals get very little UVB exposure, zone 2 consists of partial baskers, zone 3 are basking reptiles and zone 4 animals bask in UVB intense environments. Chuckwallas are recorded as basking in Ferguson zone 4 (UVI 2.6-3.5).

In the same way we allow a little variance in the temperature of the basking spot we would not worry too much if the UV exposure is a little too strong at the closest point. As long as there is a gradient present the chuckwalla will place itself in the perfect position.

UV tubes are currently available in 2 sizes, T8 and T5. The T8 lamps are around 1 inch in diameter, they must be replaced every 6 months or so and they have an effective range of 9-12 inches. T5 lamps are the newer iteration. They are around half an inch in diameter, they must be replaced every 12 months and have an effective range of 18-24 inches. For this species we would recommend a T5 unit with a strength of zone 3-4 (10% or 12%). When mounted around 30cm from the main basking spot these UVB tubes should provide the correct basking zone. The UVB unit should be mounted to the ceiling close to the back wall. This configuration will provide a nice UV gradient from the back of the enclosure towards the front and from the top of the enclosure to the bottom. With the UV and basking lamp set up this way we achieve a temperature gradient along the width of the enclosure and a UV gradient along the depth of the enclosure. This means that whatever the chuckwallas requirements they can find the perfect position within the enclosure.

Though the Chuckwalla is a basking species it may desire some time during the day in an area with little to no light. To allow this we advise providing partial and full hiding spots throughout the enclosure.

Decoration

Chuckwalla thrive in a low humidity environment with hard decorations to climb over and bask on. When selecting a bedding we try to ensure that the pieces are unlikely to stick to the chuckwalla's food, and are not going to increase the enclosures humidity. In store we normally use a coarse beech woodchip as it is clean, cheap and easy to spot clean. If you prefer a more natural looking bedding a sand / soil / clay mix would be perfect. If you plan to keep the chuckwalla in a bio-active enclosure a nutrient rich soil and clay mix with some sand for aeration would be best.

Though the chuckwalla has a temperature gradient running from side to side which we will be keeping at the correct temperatures, there are times when the chuckwalla will want to get really hot. To allow this we use dry hard wood decorations like java wood or grapevine pieces situated near the warm end but far enough from the lamps that the chuckwalla is not at risk of coming into contact with the basking lamp. The chuckwalla will climb its decoration to get to a hotter part of the enclosure.

Chuckwallas love the warmth coming from their basking lamp but they also appreciate secondary belly heat which will radiate from warm objects. Natural rocks like slate are perfect for this, so are heavy artificial ornaments. These decorations can be placed under and around the basking area and should warm up nicely. If the lamp is too low there is a chance that natural rocks could get too hot so you are best to check the surface temperature to avoid burns.

As discussed in the lighting section there will be times when the chuckwalla does not want any UV and needs a bit of shade. To ensure that the chuckwalla can get away from the light whenever necessary we advise spreading full and partial cover throughout the enclosure. Examples of full cover decorations would be caves, flat cork pieces or any other ornament that provides a shady spot to rest. Examples of partial cover would include tall plants, trailing plants and themed ornaments like skulls or a cactus skeleton.

Diet & Water

Chuckwalla are omnivorous meaning that they can eat a varied diet of vegetables, seeds and insects. Normally, this species is kept as a herbivore and provided fresh salad daily and a bowl of dry seeds. Live foods are offered very rarely and only as a treat.

For the vegetable portion of the diet, we recommend spring greens, curly kale and Italian herb mix as the base of the salad. Grated carrot, parsnip or courgette can be added for additional textures and chopped bell peppers can be added to provide colour to the salad and make it more enticing for the chuckwalla. Vegetables to avoid include onion, peas, spinach, iceberg lettuce and anything else that might be acidic or could swell with moisture. A few times a week it is advised that some roughage is added to the salad. Various weeds or plants like plantain, dandelion, chick weed can be chopped up and added to the top of the salad. Alternatively dry herb cobs or flower mixes can be rehydrated and mixed into the salad.

Both the food dish and water bowl should be kept on the cool side of the enclosure to prevent them from raising the humidity in the enclosure.

Supplements

Chuckwallas will get most of what they need from their diet but there are some vitamins and minerals that they require in higher concentrations. These are normally provided in the form of calcium and vitamin powders which are dusted onto the live food and sprinkled onto the salad.

There are many brands and types of supplements but normally they come down to a pure calcium, calcium and vitamin or vitamin only supplement. Within these groups they will also either include or exclude synthetic vitamin D3. Vitamin D3 is produced by the reptile when it is exposed to UVB and among other functions it allows the chuckwalla to use the calcium in their diet. If you are sure that the UVB levels in your enclosure are perfect you can use a supplement without D3, if you are not sure it would be best to use a supplement with some D3.

In our store we currently use a simple calcium powder with D3 and a balanced multi-vitamin with D3 called Nutrobal. For most of the animals we alternate these daily so that they get their vitamins every other day while getting calcium every day.

Breeding

If you keep a male and female together, they may breed. You do not need to do anything to encourage this. As long as they are healthy and the conditions are good, it will happen naturally. You need to consider whether you want this to happen before introducing the pair. What will you do with the babies if you incubate the eggs?

A gravid female should have access to a nesting box to lay her eggs. The box should be large enough that she can fully turn-around inside it. Inside the nesting box we use a soil mix that is kept humid enough to hold its shape but not so wet that it will saturate any eggs. We have found that ProRep spider life is perfect for this.

Once laid, the eggs should be incubated in an incubator at 29℃ (84℉). We incubate our eggs in sealed boxes on a moisture rich substrate (such as Hatchrite) to trap the humidity around the eggs. After approximately 60 days the eggs will start to hatch, the first babies to emerge will encourage the rest of the eggs to hatch.

Cleaning

Chuckwalla, as with most pets, require a clean environment to thrive. We recommend a spot clean as often as possible (every day) and a full clean every 4 weeks or so. If you are keeping the chuckwalla in a bio-active enclosure you can spot clean and monitor the enclosure instead. It may still be necessary to remove waste from the decorations, walls and substrate depending on the live custodians you have chosen for the enclosure.

When cleaning the enclosure, you should remove your chuckwalla, all decorations and all of the bedding. Once the enclosure is clear you can clean the entirety of the enclosure and all of the decorations with a reptile friendly disinfectant. The disinfectants we sell usually work very quickly and only need to be left for around 30 seconds, instructions should be found on the products packaging. Once the disinfectant has done its work it can be wiped away from the surfaces with a paper towel. In some cases, you might want to repeat the process a second time to ensure that the enclosure is thoroughly cleaned.

We would not recommend using disinfectant to clean absorbent natural decorations like cork or bark as it may seep into the product and remain. Instead, these can be scrubbed with hot water and left to dry before putting them back into the enclosure. If you need the items to be dried quickly, we would advise leaving them in the empty enclosure with the basking lamp on and doors wide open. The additional heat should evaporate a lot of the excess moisture much faster.