The desert sun was rising fast on a late spring morning. It would be hot, and the time to locate the Gila monster I was tracking was now. With my radio and antenna, I was looking for a female in Southern Nevada’s typical low, treeless scrub. The beeps from her transmitter grew louder, and finally, I spotted her as she strutted comically forward, gait like a fat bulldog. Her black-forked tongue flickered up and down, tasting the air and ground, searching for food or shelter.
I had no idea how long this female had been on the prowl. She was headed for the shade of a large acacia bush, and as she approached, so did an army of angry house finches. Perched above her, they screamed, and within a few seconds, I knew why. Two baby finches dropped out of a well-hidden nest to the hot desert floor. They were in the boiling sun, and the Gila was already resting in the shade. The larger of the two baby finches flew off on untested wings just inches above the ground. The adult birds scattered, leaving the helpless second chick to fend for itself.
The baby bird was no bigger than a human infant’s fist and would be a nice-sized meal for the tired lizard. To my surprise, it hopped into the shade and nestled against the Gila. Neither moved for 20 long minutes. Having other monsters to track, I grew impatient and had to leave. I’ll never know what happened in the end.
Small animals are part of the Gila monster’s unique diet. Called “obligate nest feeders,” they consume the buried eggs of snakes and lizards, as well as those of ground-nesting birds such as doves and quail. They seem to prefer the large, nutritious eggs of desert tortoises, but newborn mammals aren’t immune. A Gila will squeeze into the holes of kangaroo rats and mice, rabbits and ground squirrels, and devour their hapless young. A few large meals may satisfy a lizard’s requirements for an entire year.
If you’re lucky enough to see a Gila monster, you will never forget how beautiful they are. Their skin is bright pink or orange, and ebony black bands encircle the dorsal side of the body and tail. This camouflage works well for them in dappled shade, but the brilliant colors will astound the first-time viewer in open sunlight.
Despite its name, the Gila is not monstrous in size. Averaging 18-20 inches and three to five pounds, it is still the largest lizard native to the United States. Their stout bodies and fat tails give them a formidable air.
Although Gilas inhabit rocky foothills, desert scrub, grasslands, and canyons — ideal outdoor recreation terrain — seasoned hikers and trained biologists rarely see them. When temperatures are too cold or hot, the monsters hide in deep rock shelters, spending more than 90 percent of their lives there.
Yes, the Gila monster is venomous — the only lizard in the country that is — but you’ll never be envenomated unless you try to handle one. Most scientists agree that the Gila uses its venom only in defense. I’ve had them crawl over my shoes and between my legs while standing still, observing and admiring.
Their range in the United States spans southwestern Utah, Southern Nevada, extreme southeastern California, western/southern Arizona, and southwestern New Mexico. They’re hard to find in Nevada, but if you know where to look, they are common in Arizona.
Decades ago, a biochemist discovered a hormone in the venom and saliva of Gila monsters that helped the lizard regulate sugar levels during hibernation. This hormone was later synthesized and has since been used in medications, such as Ozempic and Wegovy, for treating Type 2 diabetes in humans.
There’s still much to learn about the iconic yet secretive Gila, but this much I know: It deserves all the respect and protection we can afford.