Tegu Natural history, Info and Care!
Of all the lizards in the world, few are as rewarding to keep as tegus. Their large size,
high intelligence, and willingness to accept human interaction makes them one of the
most popular pets in the reptile hobby. Keeping a tegu is probably the closest today’s
keeper can come to owning a mammalian pet. However, the same traits that make tegus
so endearing can make them challenging animals to work with, and not everyone is cut
out to deal with such a potentially demanding species. This article will focus primarily
on care of the Colombian tegu, as that is the species which which the author is most
Tegus are large, omnivorous lizards found throughout the rainforests and savannahs
South America. They belong to the Teiidae family along with ameivas, jungle-runners,
whiptail lizards, and caiman lizards. Despite bearing a strong superficial resemblance to
the monitors of the genus Varanus, tegus are not related. They are more terrestrial,
have shorter necks, and are capable of autotomizing their tails. True tegus are divided
between the genera Tupinambis, which contains the Colombian/gold tegu (T. teguixin),
and Salvator, which contains the Argentine (S. merianae) and red tegus (S. rufecens).
Recent genetic work has split the Colombian tegu is four distinct species. Tegus are large
lizards, ranging from three to over four-and-a-half feet in length depending on species,
most of which is tail. Generally, Tupinambis tegus max out at around three-and-a-half
feet and five to eight pounds and have a sleek, streamlined appearance. They have
pointed, narrow faces that make them look like a cross between a small monitor and a
skink. Salvator tegus are more heavily built, with broader, blunter snouts and seemingly
stumpier legs and weights of 15 to over 20 pounds. Another difference between the
genera is the number of boreal scales between the eyes and nostrils; Tupinambis has
one while Salvator has two.
Tegus exhibit strong sexual dimorphism, with males being
markedly larger than females, having a pair of raised, bump-like scales on either side of
the cloaca, and sporting hyper-developed jaw musculature known as “jowls.” These are a
sexually selected trait, with bigger, more fit males displaying bigger jowls. Males also
make a popping noise with them to impress potential mates.
As a result of these huge jaw muscles, tegus possess the
strongest bite of any lizard and are capable of generating bite forces of 1000 N. Unlike
most reptiles, tegus have differentiated teeth much like a mammal. This allows tegus to
take a wide variety of food items and they are actually highly specialized for omnivory;
they are the reptilian equivalent of bears. Salvator tegus are known to hibernate for up
to seven months of the year whereas the more tropical Tupinmabis tegus do not,
although some may brumate in captivity during the cooler months. When not out
foraging for food, tegus spend much of their time in burrows or termite mounds.
Throughout their range, tegus are hunted for their meat and hides. With proper care,
tegus have been reported to live for up to 20 years.
It was recently discovered that during the breeding season, male Argentine tegus can maintain their core body
temperature up to 10 degrees warmer than their surroundings, effectively making them
the world’s only warm-blooded reptile; the mechanisms by which they generate this heat
are still currently bing studied.
Colombian vs Argentine
It is not difficult to get the hatchlings of Colombian and Argentine tegus mixed up. Both
have similar black and white markings. However, Argentines have rounder faces and
have the two boreal scales. As adults, they are impossible to mistake for one another.
Argentines are three to four times the weight of their Colombian cousins and with much
more pronounced sexual dimorphism. Temperament-wise, they differ as well.
Colombians have a bad reputation as being aggressive animals, but this is not really the
case. High-strung or flighty would me more accurate descriptors, as they are lower in
the food chain than Argentines. The predators that would not hesitate to take a yard-
long, five-pound lizard would think twice before attacking one that was the size of a
small dog. Colombian tegus also do not hibernate, as they hail from more equatorial
climes. As a result of their smaller size and somewhat more antsy personality, there are
subtle differences in the care of Colombians versus Argentines but much of it can be
applied to any tegu species. From hereon out, the remainder of this article shall refer to
the Colombian tegu, Tupinambis teguixin.
Housing, Temperature, and Lighting
Being a large lizard, Colombian tegus need a large habitat. Hatchlings can be kept in a
40-gallon breeder, but if properly supported they will outgrow this rapidly. It is better to
invest in larger habitat sooner rather than upgrading as your pet grows. Adult
Colombians do well in a tank that is at least 6×3, although some keepers prefer an 8×4.
Height is not critical for while more arboreal than Argentine or red tegus, Colombians
are still primarily terrestrial. Two feet should suffice. Tegus love to burrow, and your
tank should be deep enough to allow enough substrate to permit this behavior. Coconut
coir mixing with a little sand or potting soil makes an excellent choice, as this not only
permits burrowing but will help maintain humidity.
Tegus are basking lizards and need full spectrum UV lighting to help regulate their Vitamin D3. Fluorescent tube
bulbs can be placed along the length, and it is recommended to use a mercury-vapid bulb as a
basking spot. The new best bulbs out there, that admit both UV and heat, are the Zoo
Med Powersun and Mega Ray. Place the basking bulb at one end of the tank to create a
proper temperature gradient; this will permit your tegu to thermoregulate as needed.
Ambient temperature should not drop below the mid 70’s at night and stay into the 80’s
during the day on the cool end. Being a tropical species, tegus like it hot and humid. The
basking spot should be 110-120 degrees. To accomplish this, place a large, dark-colored
paving stone directly under the basking bulb. The stone will retain heat and serve as a
rough surface to help keep your tegu’s nails trim. Humidity should be into the 70’s and
this can be achieved with a daily misting. Sphagnum moss and large water dishes can
help with humidity, and some keepers install electronic misting systems. Lights should
be on in 12-hour cycles Furnishing-wise, it is best to provide you tegu with at least one
hide, the more the better. Driftwood makes excellent decor, as it provides something for
the tegu to climb on. Make sure any furniture is well secured so it does not fall on your
tegu, especially if your tegu burrows under it. Live plants are often dug up and destroyed
by tegus, so it is best to avoid these.
Tegus are omnivores and will consume a will variety of prey in the wild, including
invertebrates, rodents, birds, fish, other reptiles, fruit, carrion, and eggs. Variety is the
key to tegu nutrition. Colombian tegus tend to be a bit more carnivorous/insectivorous
than other species, but some will take fruit. As babies, tegus can be fed daily until they
are full. Once they reach adult size, you can cut back the feeding to ever other day, no
more than two or three times a week. Tegus will take most most feeder insects, including
mealworms, crickets, and roaches. Other favored insect treats include hornworms and
grasshopper/locusts. A full grown Colombian tegu is capable of swallowing a 50-gram
rat whole and most tegus will readily take rodents. Make sure to feed frozen-thawed, as
live prey can, and will, fight back and may injure your tegu. Larger tegus make also take
chicks and quail as well. Fish are a wonderful addition to the tegu diet, and frozen
silversides are readily available at most pet stores. Certain fish species, such as goldfish,
contain a chemical called thiaminase that messes around with Vitamin B absorption and
can cause metabolic issues in your pet if keep too much, so be sure to research before
giving your tegu any seafood. Salmon is considered a tegu favorite.
Any food item without a bony skeleton should be dusted with a calcium supplement; if you have proper
lighting use power with Vitamin D3 so as not to cause an overdose. Other great food
items include snail, shrimp/crawfish (with the shell on), squid, rabbit kits, and any
whole prey item you can think of. Ground turkey was once considered a tegu diet staple,
but is nutritionally unbalanced and should only be fed in moderation; the same goes for
red meat, and pork should be avoided due to the trichinosis risk. Better you eat eat
another animal than processed human-grade meat. Most Colombian tegus are picky
when it comes to fruit, but blueberries, banana, mango, and cherries can be offered. One
great away to get otherwise stubborn tegus to eat fruit is to hide it in another food. Eggs
should only be offered as an occasional treat. As seasoned nest-raiders, tegus LOVE eggs
and some will even get addicted to them. Some owners hard-boil of scramble the eggs,
but this is merely to minimize the mess. Better to give your tegu raw eggs. Many owners
feed quail eggs as these are small enough to be swallowed whole. Egg shells make a great
source of calcium and should be included. Most lizard chows and kibbles are made with
questionable ingredients and I would not recommend feeding them to your tegu, but
there is one product which I strongly encourage adding into the diet. Reptilinks are a
whole-prey alternative that consist of ground animal meat (rabbit, chicken, frog,
venison, quail, insects), complete with connective tissue and bones, packaged into little
easy-to-swallow sausage links. They are nutritionally balanced and more calorie-dense
than a comparably sized rodent. There are even special omnivore blends with fruits and
veggies mixed in, which is perfect for tricking picky tegus to eat healthy. Including
Reptilinks in the diet also promotes healthier stools. This wonderful product can be
ordered online via the manufacturer’s website. Many owners prefer to feed their tegus
out of their home enclosure to prevent feeding aggression.
Handling and Taming
One of the reasons tegus make such great pets is that not only are the handleable, they
will actually seek out humans in search of interaction much in the manner a dog would.
Building trust with your tegu takes time and patience. Upon bringing your tegu home,
let the animal settle into its new environment. As tempting as it may be to take it out,
leave the lizard alone for at least week. Once your tegu is adjusted, you can begin the
taming process. There are several methods for taming tegus, and they can be used
independently or in conjunction with one another. One method that is popular is known
as the “bathroom method.” This involves taking your tegu into an enclosed room and
after letting the lizard run around checking things out while you ignore it, allowing it to
come to you on its own terms. This works better than force-handling as it is less invasive
to the tegu. Another method that works is to put you hand in the tank while the tegu us
eating and over time, steadily move your hand closer. This will help you gauge your
tegu’s tolerance. Initially, handling sessions should be kept short so as not to overwhelm
your tegu. Over time, you can increase the amount of time your have your tegu out.
Never dig your tegu out of its hole or hide, as this breaks trust; all animals need a safety
space. Positive reinforcement with treats is also an effective technique, and I personally
find hand-feeding is a wonderful way to bond with your pet. Many tegus have strong
feeding responses and not are are suitable candidates for this, however. Being a
terrestrial species, tegus fell the most comfortable with a sold surface under their hind
feet. When picking up your tegu, scoop them up from below rather than grab from
above, resting their underbelly and handles on your forearm, The tail can be tucked into
your armpit out of the way, while you maintain a firm but gentle grip on the lizard’s
torso. Never grab a tegu by the tail, as they may drop it. If approaching a tegu you do not
know, offer it your closed fist to sniff as you would with a dog and then gently pet it.
Properly socialized tegus seem to relish human interaction, often actively seeking their
owners out and wanted attention. Many tegus like having their jowls scratched, and
some suffer from separation anxiety when their owners are not around. Colombians are
very active lizards and generally do not sit still for long period of time. They will often
try to crawl out of your grip, so it is best to master the hand-over-hand technique
quickly. Some tegus like perching on shoulders but be careful, as they are not built for
climbing and can get seriously injured if they fall.
Tegus are one of the smartest reptiles in the world and can benefit greatly from enrichment. Treat-dispensing toys,
small animal tunnels, and supervised trips outside for sunbathing are all great ways to
enhance your tegu’s quality of life. If taking your tegu out in public, it is strongly
recommended you have your animal on a leash. Colombian tegus do not have the bulk to
fill out a small dog or even a cat harness, but those meant for pocket pets work nicely.
Having your tegu leashed will allow you to prevent your pet from getting away from you
and potentially hurt and to show to those around you who may be afraid that the animal
is under control.
Written By:Grayson Kent
Sponsored By: The Painted Reptile
18370 Oxnard st. UNIT 215
Tarzana, Ca, 91356