Gila monster
Heloderma suspectum

Body length: 9 - 14"
Diet: Eggs, small mammals, nestling birds, and carrion

The Gila monster deservedly stands as a symbol of the Sonoran Desert. The largest lizard in the US, it is one of only two venomous lizards in the entire world; the other is the closely-related Mexican beaded lizard. Venom is injected through grooved teeth in the lower jaw. Although their bite is dangerous and extremely painful, there has never been a well-documented fatality attributed to this species. Indeed, Gila monsters are very shy, and unprovoked bites are extremely uncommon.

Gila monsters are not seen by most visitors to Tonto National Monument. Are they rare? The question is difficult to answer, because they spend so much of their lives underground. Storing fat in their tails, Gila monsters can survive for an entire year on three or four meals of baby rodents, rabbits, eggs, or nestling birds. During 1994 - 1995, 15 individuals were counted in a mile-long area of Cave Creek Canyon near the Visitor Center; their most active month was May.

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