Eleven species live in Arizona, growing to lengths of less than two feet to about five feet. They feed on small rodents and can live more than 20 years in the wild.
Eggs stay within the mother's body until hatched.
Babies stay where they were born for the first seven to ten days until they shed their skin and gain their first rattle. These tiny rattlesnakes can be aggressive and deadly. Babies cannot make a rattle sound, are more difficult to see, and haven't developed the ability to regulate how much venom they inject. A new rattle appears each time a snake sheds its skin, as often as three times a year for a rapidly growing youngster. The number of rattles doesn't accurately indicate the snake's age, as they reflect the growth rate and the number that break off over the reptile's lifetime.