NOTE: Education Animals are “behind-the-scenes” animals & only appear to the public during Educational events. This includes scheduled events or programs such as daily animal mingles, private onsite programs, and zoo reaches. For more information, please reach out to edureservations@lvzoo.org.
Program and General Information
Argentine black and white tegus are a larger lizard found in the tropical rainforests, savannas, and semi-desert regions of Eastern and Central South America. This species is the largest of the “tegu lizards” reaching lengths up to 4 feet long; males are typically larger. These tegus have black and white beaded scales that are often arranged into a banding pattern across the back and tail. They are omnivores and prey primarily on smaller mammals, invertebrates, eggs, and other reptiles. They will also eat vegetation, fruits, and seeds. They have a very long and powerful tail that they can use to defend themselves. Brumation for wild tegus occurs between September-March, and breeding will begin a few weeks after waking up and will last about a month. Females build a nest and lay 12-30 eggs about 1-2 months after breeding. Eggs will hatch after a 120- 170 day incubation period. Young tegus will mature around 3 years of age.
Diet
Tegus are omnivores, meaning they eat both plant and animal matter. As juveniles, wild tegus eat a wide range of invertebrates, including insects, spiders, and snails, as well as, fruits and seeds. They may seek out eggs from other reptiles and from birds’ nests, and will eat small birds and other vertebrates. As adults, they will continue to eat the same diet, but can now prey on larger mammals and reptiles.
Similar to snakes, tegu’s use their tongues to sniff out prey. Their
tongues are forked to assist them in figuring out which direction to go for food. The Jacobson’s organ on the roof of the mouth will process the information from scent particles on the tongue and determine which side of the tongue the scents came from.
Tegus are diurnal and more active during the day.
Habitat and Range
Black and white tegus are native to the tropical rainforests, savannas, and semi- desert regions of Eastern and Central South America. They have also been found disturbed habitats such as forest clearings, roadsides and fence rows, and can adapt to both drier and wetter environments.
Tegus are terrestrial lizards, rarely climbing more than a few feet off
the ground. And although they prefer the land, tegus are also excellent swimmers and can stay underwater for long periods of time. To stay hydrated and protect themselves from the extreme temperature of their native habitats, these lizards will dig or take over burrows deep underground where temperatures do not fluctuate a great deal.
Tegus are considered an invasive species in Georgia and Florida.
Common Physical Features
Tegus are a relatively large and stocky lizard. They can reach lengths of up to 4.5 feet and can weigh upwards of 15 pounds. They have a mottled black and white coloration that often is arranged into a banding pattern across the back and tail. Hatchlings display similar markings, but are more green in color; this green color will fade to white as they grow. Tegus have powerful jaws and sharp teeth, as well as thick claws. Males are larger and thicker than females. Males also have bigger jowls (“chubby cheeks”), which not only house large
jaw muscles, but also help male tegus attract a mate. The larger the jowls the stronger and more attractive the tegu!
Adaptations: Tegus use their out their tongue to sniff out prey items. Like other reptile species, Tegus have a Jacobson’s organ in the roof of their mouth. They will stick out their tongue in order to pick up scent particles in the air or from the surface of objects. Their tongues are forked at the end, splitting in two directions in a V-shape, allowing the tegu to pick up scent particles from two different directions. When the tongue is brought into the mouth to the Jacobson’s organ, the organ will process the information and determine which side of the tongue the scents came from. This will inform the tegu which direction to go to find that scent. (If it picks up the scent on the left fork, then it knows to go to the left. If it picks it up on the right, then it goes to the right. And then if it picks up the scent on both forks then it knows the scent is coming from straight ahead.)
Because of their large size, tegus don’t have many predators. However, if a predator does come along, tegus have a few defense mechanisms for protection. If tegus feel threatened they will puff out their cheeks, open their mouth really wide, and try to make themselves look bigger. They may also huff and stomp as a warning. This is especially useful for defending their territory from other tegus. Tegus are also capable of running at high speeds
and can run bipedally (on their back legs) for short distances.
If this warning display does not deter the potential threat, tegus will begin to thrash their incredibly powerful tail around. The tail can be curled into a J-shape and used like a whip to keep threats away. If this warning also fails, then Tegus can charge and bite. They have a strong jaw that clamps down and is unlikely to let go.
Many lizard species can drop their tail, a process known as autotomy. While Tegus appear to have the ability to lose their tail and regenerate it, it is unlikely that they will do so. Their tail is important for locomotion and defense, and because Tegus do not have many predators, it is not worth the energy needed to regrow the tail if dropped. There is very little research done on the family Teiidae and their ability to autotomize their tail, but from what research has been done it is likely that smaller members of the family Teiidae are more likely to drop their tail than larger members like the Tegu.
Behavior and Life Cycle
During the colder months of September – March tegus will go into
brumation, the reptile equivalent of hibernation. During this time they will burrow under the ground, their heart and respiratory rate will slow and their activity level and body temperature will drop. Breeding occurs a few weeks after waking up from brumation. Tegus are typically solitary, but will come together to breed and will sometimes brumate in groups.
Tegus are oviparous, or egg-laying. After a successful breed, females will begin building a nest and will lay eggs about a month or two later. The average clutch size is around 12-30 eggs. The female guards the nest and will aggressively defend it against all perceived threats. The eggs will hatch anywhere from 120-170 days later. Hatchlings are around 8 inches and will stay with their mother for a short while. Maturity occurs around 3 years of age.
Conservation Messaging
Purposeful Pet Ownership
Tegus are becoming more popular in the pet industry and pet trade. Before buying these lizards one should know where they were bred, as catching them from the wild is decreasing their populations, and wild caught tegus can be very aggressive. Potential pet owners should also know the size that these lizards reach and the amount of space required, as well as what these lizards need for daily care. Many people don’t realize just how much work goes into caring for reptile species. Reptiles require specific lighting, humidity, space, nutrients, substrate, heating, and if they do not receive the proper care then that reptile’s health can decline rapidly. It can be difficult to find veterinarians that are equipped to care for reptiles if they get sick.
What can we do?: Be sure to fully research any pet before buying one. While you may think a reptile would make a cool pet, it’s important to know all of the care that goes into providing that animal with the best possible welfare, and as mentioned before reptiles require a lot of extra care. It is important to make sure that if you do buy an exotic pet that you are buying it from a reputable breeder, someone who knows how to properly care for the animal and hasn’t taken that animal from its natural habitat. Do not release an unwanted pet into the wild. While you may think that you are doing something good by releasing the animal back into the wild, animals that have been kept under human care often do not know how to survive on their own out in the wild and could end up getting hurt or dying if left to their own devices.
Fun Facts
Bibliography
