Gila Monster: The Venomous Reptile of the Southwestern US

Knoji reviews products and up-and-coming brands we think you'll love. In certain cases, we may receive a commission from brands mentioned in our guides. Learn more.
The Gila Monster is a slow-moving poisonous lizard of the American Southwest. Best left alone wherever found, the Gila Monster is sought after by black-market traders and sometimes are smuggled across state and national line for sale.


Gila Monster: Venomous Reptile of the Southwestern US

A venomous reptile that is found in the southwestern United States and northern regions of Mexico, it is the only venomous native to the U.S. and is just one of two venomous lizards known to exist in North America.

Gila Monster!

Slow moving, this lizard is of little threat to humans yet homeowners and hikers often kill these on sight because of their fearsome reputation. Gila Monsters are protected under state laws (Arizona and Nevada) and are not permitted to be owned in these states, yet other states have no law specifically declaring them illegal to possess.

Oddly enough despite their venomous bite, they have other attributes that could possibly make them a desired captive for the serious herp lover. The do not require much exercise room, are easy to care for and readily accept commercially-prepared food preparations.

Close-up view of a resting Gila Monster, with brilliant orange and black colors

Image Source

Their sluggish, slow-moving and shy behavior makes it unlikely that a human would be bitten by one unless they were harassing, handling or otherwise presenting themselves in a confrontational manner. A Gila Monster would likely hiss, gape its open mouth and back away from a threat. Generally, one would only be bitten if handling these lizards, whose formidable bite is said to be likened to ‘bulldog mentality.’ They clamp down hard, gnaw once or twice to inject the poison and then do not readily let go.

Gila Monsters eat pinkie mice, baby rabbits, nestling birds and eggs found on the ground. Often, they enter a burrow and eat the nestlings of whatever it finds living there. They then assume the ready-made burrow as their home. Despite their innate slowness, in close proximity they can lunge and bite with surprising speed. Their venom is probably more of a defensive mechanism than a hunting aid as their lack of speed would make it difficult for them to catch anything that can move away from danger. For the average herper a Gila Monster is an unwise choice. Although the Gila Monster and a related specie called ‘Beaded Lizard‘ are the only two known venomous lizards, the bite of the Komodo Dragon has long been known to be toxic. It had been believed that it was the potpourri of toxins in its saliva that did the trick, but I recall reading recently that it actually injects a venom into its prey upon biting. A venomous bite in a lizard is still an anomaly with even just these three examples.

A Gila Monster’s Tongue

A Gila Monster reptile being held tightly, mouth open and blue-grey tongue is visible

Image Source

Grayish-blue in color but probably very attractive to another Gila Monster, their tongue actually looks sickly. Some reptiles like the Blue-Tongued Skink also have blue tongues but they can see into the ultraviolet light spectrum a little bit so the tongue might look brilliant red to another skink.

Gila Monsters make their dens in abandoned burrows created by other animals or in burrows they have dug themselves. Spending as much as 95% or more of their time underground, they are seldom seen even though they are diurnal (day-dwelling) creatures.

Gila Monsters lay an average clutch of between 5 and perhaps as many as a dozen eggs in late June to mid August. The eggs incubate from the time they are laid until the early spring. This is unusual and makes them the only known specie of egg-laying reptile to overwinter their eggs.

Gila Monster Resting

A resting Gila Monster lizard

Image Source

Carefree Gila?

A child's slides at a playground in the shape of a giant Gila Monster lizard

Image Source

This image is tagged as being a playground slide in Carefree, Arizona. Okay, I’m a little frightened now. This is one very interesting themed piece of playground equipment and even though I love reptiles the thought of mounting the giant lizard and sliding down its back does not come to mind as anything akin to ‘carefree.’

Gila Monster Skull

Gila Monster skull in a plastic bag

Image Source

This looks like an alien ‘Predator’ skull but those two eye-sockets on the front are actually nasal passages. The eye sockets are on either side of the head. Look at those teeth! Their venom is chewed into the flesh of their attacker, thus injecting a larger quantity. Their bite is said to be excruciatingly painful and in humans causes nausea, vomiting and sometimes death.

Gila Monster skull in profile

Image Source

Side View of a Gila Monster Skull

Live Gila Monsters are sometimes smuggled across the border from Mexico or over state lines where they are sold for a premium on the international black market. A black market Gila Monster can fetch a $1000.00 or more to a reptile enthusiast willing to purchase one.

Some years ago, a vehicle was stopped and an alert Inspection Agent noticed that a blanket in the truck of the car he was inspecting was ‘moving.’ Upon careful inspection, several dozen wild-collected Gila Monsters were discovered. They had been intended for sale on the international black market.

Storm Drained Plugged?

Gila Monster crawling up into a plastic storm drain

Image Source

It could be a Gila Monster lizard. Don’t reach up in there, call a professional.

This is probably a zoo specimen but if I lived anywhere that had venomous reptiles or anything that stings, crawls or bites for that matter, I’m going to let the professional contractor figure it out. Be it tarantulas, scorpions, rattlesnakes etc. I’m not reaching up into anything like this drain pipe for any reason.

A medical practitioner of the late 1800s was quoted in the Arizona Graphic (Sept. 23, 1899) having said of Gila Monster bites;

“I have never been called to attend a case of Gila monster bite, and I don’t want to be. I think a man who is fool enough to get bitten by a Gila monster ought to die. The creature is so sluggish and slow of movement that the victim of its bite is compelled to help largely in order to get bitten.”

Anywhere up to around a dozen people are bitten each year in the United States from Gila Monsters, and almost always it comes handling them. In Arizona at least, they are protected from being owned by state law. While legal to own in other states, federal laws are invoked for the sale and transportation across state or international borders. When an animal becomes a sought-after commercial commodity there is a need for legislation to control the sale and distribution. Gila Monsters are best left in the desert where they belong.

1 comment

Posted on Nov 26, 2010