I was 10 years old when I set up my first desert terrarium. My mother had ordered a “desert kit” from a biological supply house—reptiles in a pet store were virtually unheard of at that time—and I gleefully unpacked the large shipping box. The box contained a 10-gallon tank, four kinds of cactuses, a bag of sand and one rather angry collared lizard, which greeted me with a surprisingly painful bite. That was it—no lighting, no heat source, no food, no supplements and not even a thermometer. More importantly, there was not a single word of instruction.
Things have come a long way. Selling the desert terrarium is now the provenance of the pet store; and today’s retailers have all the tools to do a far better job than the pathetic kit I had as a boy. The desert is a rather specialized environment to try to reproduce in an indoor setting, but many of the most popular reptiles in the pet market are desert inhabitants, and retailers need to be familiar with this type of setup.
Many people start off thinking that they want a specific microenvironment, like a desert. Populating the display is often an afterthought, but this approach doesn’t bode well for the animals. I always insist my customer choose the pet first, and then outfit a cage to best suit its care and maintenance. So, which herps work in a desert tank?
Lizards automatically come to mind as desert fauna. The most popular pet lizards on the market, bearded dragons and leopard geckos, are both scrub to desert animals. However, there are many other fine choices. The uromastyx, aka dab lizard, is a Mid-Eastern and North African lizard that comes in a variety of colors and sizes. It is a hardy animal, noteworthy for its unusual diet. The dab lizard is primarily vegetarian and desert-adapted to eating seeds, nuts and dried fruit.
Do you remember the episode of Outer Limits with the sand monsters that were swallowing up astronauts like kibble? Sandfish are beautiful skink-like lizards, with charming faces and amusing behaviors, that dive in and out of loose sand.
The Texas collared lizard is a stunning lizard with vivid yellow, brown and aquamarine colors and patterns. It readily adapts to captive life, although it rarely becomes handleable, as I quickly learned at age 10. Beware: it also has a penchant for eating other lizards.
Just as many people think they want a chameleon until they find out how delicate and difficult they really are, lots of folks are enchanted by the horned lizard, aka the horny toad. The unfortunate truth is that these animals have evolved to be predators of ants—and often specific species of ants—making them a poor choice for anyone but the most experienced herp keepers.
Snakes and More
Sand boas are a primarily African genus of small fossorial snakes with beady eyes and typically docile temperaments. The Kenyan version is particularly pretty, with a chocolate background highlighted by bright orange dorsal patterns. Pretty as they are, they do choose to remain hidden most of the time.
Most other desert species of snake are difficult for one reason or another; they are fast, difficult to tame or venomous. Only a few colubrid (“true” snake) species are desert dwellers, but I find that with surprising consistency, they are not easy to work with in an desert tank and are more easily kept in a standard snake setup.
Very few species of tortoise actually live in the desert. Their vegetarian diet precludes that level of barrenness. However, many of the scrub species, from Greeks to spurred tortoises, enjoy the temperatures and lighting of a desert situation and will thrive in a faux desertscape.
Once a client has chosen the animal, we can move on to the enclosure. Start by choosing the right size tank. Producing a diverse range of temperatures in a desert tank is paramount. The animals need to thermoregulate by as much as 20 degrees, requiring substantial room. Even baby desert dwellers require no less than a 10-gallon tank, and larger individuals might require a space equivalent to 40 or 50 gallons.
It is not a case of overselling to give a desert dweller both an undertank heating pad and overhead spotlight. The undertank pad provides a nice ambient heat, while the spotlight offers a discrete point of intense heat for basking. For many years, I have been a big fan of the Zoo Med Basking Bulb, which unlike most spot bulbs, shoots out a fine beam with quickly gradating rings of lesser heat, proving a wide range of temperatures in a relatively small space.
I have often responded skeptically to manufacturer claims about the benefits of UVB bulbs, but if ever there were a situation in which they were an absolute necessity, the desert tank is it. While they do not replace the need for vitamins and calcium supplementation, UVB bulbs stimulate more natural behavior and engender a more aggressive feeding response in most arid species. In most cases, I would use an 8.0 or 10.0 strength, although some species, like bearded dragons, fare well with a 5.0 bulb.
This will come as a shock to some, but sand is rarely the best bedding for desert animals, and for some species, it can be remarkably detrimental. For instance, tortoises can get sand grains wedged between their skin and shells, resulting in great discomfort and skin lesions. Many lizards—famously, leopard geckos—will actually ingest sand in search of extra calcium, sometimes to the extent of causing internal blockages that result in death. For many animals, a good grade of aspen or pine bedding, while it may not look quite right to our eye, is in reality much more comfortable to the cage’s inhabitants.
On the other hand, some animals thrive in sand. Sand boas and sand fish love it, as their names imply. Adult bearded dragons and uromastyx also thrive on it. There are some fine products on the market that mock sand but in fact are digestible vitamin supplements. As with the UV lights, these do not replace vitamins or calcium, but they provide good, safe bedding that can also keep animals well supplemented.
So, now we have chosen a pet and a nice tank that is well lit and heated, and substrated appropriately. This means we are down to providing appropriate accouterments. These are entirely dependent on the needs of the pet. With the exception of fossorial animals, which use the bedding itself as a hide space, these pets require a cave or a piece of driftwood that is big enough to provide a feeling of security and a place to escape the light. Basking lizards should have a branch big enough to provide several perch and temperature options.
What is most always an obvious need for pets, the water dish, is usually an anathema in a desert tank—it tends to keep the cage too humid and just seems to muss up everything. Most desert lizards have evolved to be dew drinkers, and a good misting in the morning and evening should suffice nicely. Tortoises get most of their liquid from their diet, but a brief soak in shallow water in the morning will let them drink and defecate. Snakes are generally more amenable to a water dish, but choose one with low sides and easy access, especially for the boas.
A desert tank is often a wonderful window into a unique and wholly different world than that of day-to-day life and can give the brain a mini-vacation—unless you live in a desert.
Owen Maercks has enjoyed being immersed in the world of professional herpetoculture for nearly 30 years. His store, the East Bay Vivarium in Berkeley, Calif., is one of the oldest and largest herptile specialty stores in the U.S.