There are many species of lizards. Some of the more popular domestically kept species include iguanas, bearded dragons, chameleons, and geckos. The specific behavior of lizards varies depending on species. Some species, such as iguanas, are active during the day, while others, like the leopard gecko, are active at night. Some species of lizards, such as similarly-sized bearded dragons, may do well in groups, while others, such as chameleons, should be housed individually.
In general, lizards should be handled gently under the body and never caught or picked up by their tails, as their tails can sometimes break off. Certain lizards, such as young iguanas, are quick and jumpy. Older iguanas, which can reach several feet in length, can be aggressive and dangerous, whipping their tails and biting, especially when they reach sexual maturity. Other lizards, such as bearded dragons, tend to be gentler and more amenable to handling. Regardless of species, all lizards can carry Salmonella bacteria; thus, their cages and feeding bowls should be kept away from human food, and any surface they have contact with outside of their enclosures should be disinfected. Care should be taken to wash hands after handling any lizard.
Specific housing requirements vary according to species. Smaller lizards, such as geckos, may be housed in well-ventilated aquariums protected by screens on top, so that other predatory pets, such as cats and dogs, don’t have access to them. Larger lizards, such as bearded dragons and iguanas, need enclosures at least 2’x4’ and should be large enough to enable climbing. Chameleons generally do better in wire enclosures with a minimum size of 2’x2’x3’. Chameleons need to climb, so enclosures should be taller rather than wider. Acceptable substrates for the tank bottom include paper towel, newspaper, recycled paper products, or rabbit pellets.
Particulate matter bedding, such as sand, soil, gravel, corncob, walnut shells, and wood shavings/chips are not recommended, as they are indigestible if eaten, can encourage bacterial/fungal growth, and can sometimes be irritating. All lizards should have hide boxes, large rocks on which to rub off shedding skin, and open water bowls in which to bathe. Many lizards also need to be misted with water daily to keep hydrated. Iguanas, in particular, need high environmental humidity, while bearded dragons do better with a much lower moisture level. Chameleons will not drink standing water but require a drip system (commercially available).
Chameleons and iguanas, especially, must be provided with branches for climbing. All lizards require supplemental heat (provided by an over-the-tank bulb), so that a temperature gradient is established, with a hot/basking zone and a cooler/shade zone, the temperatures of which vary depending on species. Generally, lizards also require 10-12 hours a day of exposure to ultraviolet (UV) light in the UV-B wavelength; UV bulbs must be charged every six months to ensure adequate UV-B exposure. Mercury vapor bulbs that provide both heat and UV light are also available. Commercially available “hot rocks” are not recommended, as they can cause burns.
Some lizards, such as iguanas, are herbivores (eat plant matter only), while other lizards, such as chameleons and bearded dragons, are omnivores (eat both plant matter and animal matter). Still others, such as some geckos, are carnivores (eat animal/insect matter only). Every day, iguanas can be fed calcium-rich greens such as collards, turnip and dandelion greens, bok choi, romaine, kale, Swiss chard, spinach, cilantro, and escarole. They may also be offered alfalfa hay and grass, and lesser amounts of other vegetables (carrot, squash, pepper, broccoli, peas, beans, okra, sprouts), plus occasional fruits (banana, apple, melon, papaya, kiwi, plum).
Bearded dragons may be fed mealworms, crickets, superworms, wax worms, and pinkie mice. These food items should be dusted with a vitamin/mineral supplement containing calcium several times a week for young dragons and twice weekly for adults. Dragons also should be fed greens, similar to those fed to iguanas, smaller amounts of other vegetables (like iguanas), and even lesser amounts of fruits.
Young growing dragons eat insects daily with lesser amounts of greens; adults tend to consume more greens and fewer insects. Chameleons predominantly eat insects (mealworms, crickets) and may also eat roaches, snails, and silkworms. Care must be taken not to overwhelm chameleons with insects, as insects can chew on chameleons and injure them. Young chameleons should be fed daily; adults should be fed 3-4 times a week. Chopped greens, vegetables, and small amounts of fruit also may be offered.
Chameleons also should receive supplemental calcium dusted on prey. Leopard geckos live mainly on insects dusted with calcium powder (every other day for adults). Juvenile geckos are fed daily, while adults are fed 3-4 times per week. Crickets should not be longer than the length of the gecko’s head and generally should not be fed in excess of 4-6 per feeding.
Most lizards also need supplemental vitamin D, as well as a mineral supplement. Your reptile veterinarian can best advise you about your pet’s specific requirements.
All lizards should be examined by an exotic animal veterinarian initially after purchase and annually after that. They should receive a complete physical examination, as well as a check of the feces for parasites. Dietary and environmental requirements should be reviewed, and every lizard should be dewormed when purchased.
All new lizards should be kept separate from other reptiles for at least a month. Many reptiles should not be housed together. Your veterinarian can best advise you about housing. In general, different species of lizards should be housed separately. Good preventative medicine helps ensure a long, healthy life for your pet lizard.