Scientific Name: Tupinambis merianae
Adult Size: 3 to 4 1/2 feet long
Average Life-Span: 15 years or more
Temperament: Cat-like; tames down very well with regular handling and socialization from a young age
Range: Argentina, Brazil and Uruguay
Habitat: Rain forests, forest-edge savannas and meadows of temperate climates
The giant black and white tegus of South America are the most intelligent and highly adapted of all lizards. They typically inhabit forest-edge savannas and adjacent rain forests of Argentina and parts of Brazil and Uruguay. They are largely terrestrial, and spend copious amounts of time in deep burrows which afford them protection from dehydration and shelter from extreme temperatures. As pets, tegus can be the most rewarding of the larger lizard species to keep. Their large size, attractive appearance and cat-like demeanor have quickly propelled them into the herpetocultural spotlight. The most common color you can find them in is a stunning black and white, with babies having a bright green sheen to them that fades with age. Another common color is a lovely brick red which has been gaining in popularity in recent years.
Tegus are fast-growing lizards, often reaching sexual maturity in 3 years or less. Males are larger than females, sometimes exceeding four feet in length with a solid, muscular build. Females usually grow into the 3 feet range and have slighter features than males. This species can live to be 15 years or more given that close attention is paid to diet and other basic husbandry considerations.
Hatchling tegus are about 8 inches in length and can be kept comfortably in a 30 gallon aquarium for the first few months of their lives. However these are very fast growers if given the proper nutrition, and will continuously need larger enclosures allowing for proper exercise, burrowing activities and thermoregulation. Young tegus can be housed communally, but be sure that all the animals are the same size and watch for food-related aggression among competitive little piggies. A single adult male should be provided with an enclosure having a foot print of no less than 6 feet X 2 feet. A pair can be housed in a slightly larger enclosure (6 feet X 3 or 4 feet), although separation will be necessary for when the breeding season occurs to prevent aggression. A single female will require less space than adult males (5 feet X 2 feet). Tegus are active and should be given as much space as possible. Converting an walk-in closet or small room into an enclosure should not be considered out of the question. Secure well-ventilated enclosures that allow for deep substrate are highly recommended, as tegus love to dig and burrow.
As a tropical species, tegus will require warm temperatures during most of the year unless they are being brumated (cooled down) for reproductive cycling. Ambient temperatures within the cage should be between 80 and 90 degrees F during the day, dropping to 5 to 10 degrees cooler at night. During daylight hours, a basking spot of 90 to 100 degrees F should be available. Heat can be provided through the use of under-tank heating pads, standard heat bulbs and ceramic heat emitters. The use of a high-quality thermometer, preferably one each on the cool side and the warm side of the cage, is highly recommended. In captivity the use of a full-spectrum UV light is essential for the long-term health of your lizards. These may be standard fluorescent UV bulbs, or self-ballasted mercury vapor bulbs (such as Zoo Med's PowerSun bulbs) which can double as both a source of heat and essential Ultra Violate light.
Bark or mulch type bedding are recommended for tegus. Orchid bark, cypress mulch and coconut husk are all acceptable. The substrate should be deep as to allow for digging and maintaining adequate humidity. Tegus tend to like rearranging their enclosures, so elaborately decorated cages are unnecessary and impractical as well. However, providing a few hiding places such as half-logs or cardboard boxes is recommended.
Tegus of all sizes will require a large, sturdy water bowl, preferably one where the animal can submerge its entire body. In captivity, humidity levels between 60 and 80% are ideal. This can be achieved through humidity-promoting substrates and regular misting of the enclosure with room temperature water. If kept too dry, tegus are prone to shedding problems, most notably with the skin of the toes and tail, making regular soaking a good idea.Tegus are typically considered omnivores, although many captive diets do not reflect this tendency. In addition to an assortment of appropriately sized insects (crickets, mealworms, waxworms, roaches), various high calcium fruits should be regularly offered. Willingness to accept fruits will vary from animal to animal, but even a small amount can add a lot of variety and essential nutrients to the tegu diet. Rodents may be offered, though sparingly, as they tend to be high in fat, and tegus are simply not designed to digest large quantities of fur. Instead, a balanced dietary supplement can be created using raw, ground turkey, whole eggs (with shell), and bone meal or an equivalent calcium/vitamin supplement. This mixture has been widely used by zoos and hobbyists and can safely constitute up 75% of the tegu diet. Tegus grow quickly and have very active metabolisms. As such, regular feeding is necessary. There is no rule of thumb as to exactly how much to offer, but tegus should have a filled-out appearance when they are full. Start by offering young tegus food daily (as much as they will consume in about an hour), and adjust quantity and frequency as needed. Calcium and vitamin supplementation is especially important for young tegus. A high quality calcium supplement complete with vitamin D3 should be lightly dusted on all food items. A multivitamin is also highly recommended, and should be added to food at least once a week, less frequently if the diet is exceptionally varied.
One of the major draws to owning tegus is their typically calm demeanor and ease of handling. Babies should be handled regularly from an early age to ensure proper adjustment to human presence. Argentine tegus rarely bite, but more often will squirm about in your hand, and even this behavior will go away with time as they begin to trust you. Avoid hand feeding, as the last thing you want is a hungry tegu that associates any part of your body with food!