Region: southern California, southern Nevada, southwestern Utah, western Arizona, northwestern Sonora and northern Baja California.
Habitat: Deserts and rocky areas.
Size: 2-3.5 feet
Gestation: 3-4 months. Mating occurs in spring and young are born in summer.
Diet (wild): Small mammals, lizards and occasionally birds.
Diet (zoo): Mice
Life spans (wild): 15-20 years
Life spans (captivity): 15-20 years
Endangered Status: They are classified as least concern
Threats in the wild: People, other snakes (such as kingsnakes), birds of prey and large mammals.
Anatomy/Physiology: In general, males are slightly larger than females. They are heavy-bodied with a thin neck and large, triangular head. There is a lot of color variation in this species including off-white, pale-yellow, gray, tan, pale-orange, brown and almost black largely dependent upon where it is found and the ground color of the natural rocks/substrate from the area. They have evolved to match their surroundings in order to enhance their ability to camouflage. They have dark, speckled-banded markings on their back, and rings around their tail. The tail has a rattle on the end used to warn predators.
How big do families grow?: They are solitary animals and only get together in pairs for breeding; many rattlesnakes (and other snakes) congregate communally in hibernacula during the cooler months for brumation.
How do they communicate between one another?: Scent
Do they have any special skills?: Rattlesnakes are also called “pit vipers” because they have a heat-sensitive organ known as a “pit” on each side of the head that helps them locate and aim at prey. A rattlesnake can detect prey that are as little as 1/10 of a degree warmer than their background.
What is their daily schedule?: They spend most of their days sleeping, foraging (these snakes are sit-and-wait predators that lie motionless and ambush prey) and/or basking in the sun.
Any interesting facts about our Southwestern Speckled Rattlesnakes at the Phoenix Zoo?: Rattlesnakes are ovoviviparous which means they give birth to live young. Instead of laying eggs, the eggs are carried inside their bodies and hatch before live birth is given. Babies are born without rattles but will gain a rattle every time they shed.