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    National Park Arizona

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Gila Monster

Gila monster

NPS

Gila Monster (Heloderma suspectum)

Gila Monsters are one of only two venomous lizards in the world! They produce venom in glands of the lower jaw and channel it along grooves in the teeth for secretion. Once a Gila monster bites, it generally holds on tight, chewing more and more venom into the bite. The venom is believed to be a defensive weapon as most of the lizard’s prey is defenseless.

Gila monsters are most active during daylight from spring through fall, but they spend up to 98 % of their time in their burrows. When they are above ground, they tend to move rather slowly and will first try to escape if a predator comes near. They will also hiss and open their mouths very wide (this behavior is called gaping), showing off their pointy teeth. They bite only as a last resort. The bite is extremely painful to humans but rarely fatal. Most human bites occur when someone purposely aggravates or tries to handle a Gila monster. If left alone, they are harmless.

Body size: 9-14 in. (22.8-35.5 cm)

Diet: Small and young mammals (baby rabbits, for example), nestling birds and eggs, reptile eggs, and carrion

Did You Know?

Fire

Buffelgrass burns at 1300-1600 F, hot enough to melt aluminum and the fire can travel near the speed of the wind. Even in moderate weather, it can travel at 2-3 mph with 12-18 ft flame lengths, making it a real threat to the lives of firefighters