Desert Developers Threaten Gila Monsters


The name fits: Gila monster. With beady eyes and beaded orange and black skin, the large, venomous lizard can put you in the hospital with its powerful bite.

But Gila monsters are no match for bulldozers and development.

A well-known symbol of Arizona’s desert wildlife, Gila monsters love the craggy rocks of lower desert mountains. Unfortunately for the lizards, the rich and famous do too.

Since the 2-foot-long lizards are usually well hidden under rocks and in underground burrows, it isn’t clear how many are being displaced--or buried alive. But most of those forced out by homes must live out their lives in captivity, as Gila monsters rarely survive being transplanted.


It is clear that upscale developments are doing most of the damage. That’s because elements that draw people and Gila monsters are the same: stunning saguaros, varied vegetation, birds, rabbits and other wildlife.

“The richer, more affluent developments are really doing the worst damage to them. It’s not the little trailer park lots,” said David E. Brown, an Arizona State University professor who coauthored a book on Gila monsters.

The lizards, while not considered threatened or endangered, are protected under state law because they are unique. Found exclusively in Arizona and small sections of bordering states, they are one of only two known species of venomous lizards in the world. The other, the Mexican beaded lizard, is a close cousin.

While not deadly, a bite from a Gila monster can make you wish you were dead, said Sam Huselton, an assistant at the Adobe Mountain Wildlife Rehabilitation Center, home to displaced Gila monsters.


And while they look slow, the moseying lizards are known to whip their heads around and grab onto threatening hands with lightning speed. Once they lock their talon-shaped teeth down, they gnaw on victims, pumping in venom, said Randy Babb of the state Game and Fish Department.

A bite usually requires a hospital visit and is described as excruciating.

Just how many Gila monsters are living in the wild--and how many are being displaced--is almost impossible to tell because they are so secretive, Babb said.

“Lord knows how many of these we’ve buried,” Huselton said as she held one of the displaced creatures. “They can just go right over their little dens and we’d never know.”


Gila monsters spend about 95% of their time hidden, and they only pop out of their homes once in a while to mate or get food. They stay underground all but about two weeks out of the year, he said.

During the spring, they eat newborn birds or rabbits, storing most of their sustenance in their bloated tails. The “original coach potatoes,” as Brown likes to call them, can live off two or three meals a year.

They are not, however, very good at living outside their home range, making development especially hard on them. They can rarely be moved more than a half mile with much chance of survival.

“There seems to be a misconception that if you take an animal and drop him in another area, he’ll be fine,” Babb said. “It’s akin to dropping you or I in any strange city around the world. Animals put in strange environments do not find their way around any better than people do.”


That means a growing number of the lizards are showing up at Adobe Mountain’s doorstep. Most are waiting for homes in zoos or to be studied by researchers.

Peter Galvin, a biologist at the Tucson-based Southwest Center for Biological Diversity, a private environmental group, said the decline in the number of Gila monsters is not alarming yet, but it is certainly cause for concern.

“You just look out in any direction . . . Every acre of the Sonoran desert gets gobbled up. It’s just gone for Gila monsters and for other wildlife in the area,” he said.

“Gila monsters have long been thought of as powerful symbols of the Sonoran desert. People move here because they love the Sonoran desert. Are we just going to eat up the desert until the things we moved here for are gone?”