Their tail serves as a fat storage organ which they utilize when food is scarce and they can survive several months without eating. Gila monsters are nocturnal and are one of only two known venomous lizards. Their venom is produced in glands along the lower jaw and is not injected like snakes but rather it flows into the open wound as the lizard chews on its victim. Most prey can be taken without venom and it appears that the venom is used primarily for defense instead of killing prey. Their jaws are extremely powerful and well known for its persistent death grip.
Gila monsters are carnivores who seem to rely more on taste and smell to hunt than on vision.
They often track prey by licking the ground to pick up scents with their forked tongues. They crawl with an awkward lumbering gait, but can be deceptively quick. The primary food for gila monsters are small mammals, eggs of birds and reptiles, and adult lizards. Their enemies include coyotes, owls, hawks, eagles, and other reptiles when young. The gila monster mating season occurs during the summer months and 3 to 10 eggs are laid in the fall to winter months.