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Gila Monster (Heloderma suspectum)

gila monster

DESCRIPTION: L=1.5' (46cm) including tail. Overall yellowish to pinkish to orangish with a variable black pattern. The snout and tongue are black. Scales are bead-like. Pronounced "HE-la" monster.
NATURAL HISTORY: Venomous. Usually must be handled to get bitten; watch out, they are faster than they appear. Gila Monsters may bite and not let go, continuing to chew and inject more venom into the victim. Venom is released from venom glands in the lower jaws and travels up grooves on the outside of the teeth and into the victim. The toxin is extremely painful and medical attention should be sought immediately (the bite is potentially fatal -- when bitten, call the
Arizona Poison and Drug Information Center at 626-6016 in Tucson and 1-800-362-0101 elsewhere in Arizona). See also section on Venomous Animals. Gila Monsters are the largest and only venomous lizard in the U.S. The only other known venomous lizard in the world is the Mexican Beaded Lizard (H. horridum) which occurs just to the south of us in Sonora, Mexico. The Mexican Beaded Lizard is larger, has an all-black head, and pink tongue.

gila monsterCarnivorous, feeding mostly on newborn rodents and rabbits/hares, but also eating birds, lizards, and bird and reptile eggs. They use powerful claws to dig out the nests of these animals. Just 3 or 4 meals (each meal may represent 35% or more of their weight) per year is sufficient; they store fat in their tails that, when metabolized, provides energy and water. Diurnal, mostly from March to June. Hibernate during the winter. Gila Monsters may spend up to 98% of their lives underground (mostly in burrows); water evaporates from their skin easily compared to other lizards, thus staying underground reduces rates of evaporation. Eggs are laid late June to mid August and don't hatch until the following spring (this is the only North American lizard known to have its eggs incubating during the winter). Gila Monsters are both cryptically colored and aposematically colored. Their black snout makes them difficult to see as they look out of their burrow. The pink and black coloration is good camouflage when they are still in the dappled light under a shrub or tree. But that same pink and black coloration offers a good warning when in the open, especially when accompanied by gaping and hissing.

The Gila Monster is a protected species and it is illegal to collect, kill, buy, or sell them in Arizona without authorization from the Arizona Game and Fish Dept.