Western Diamondback Rattlesnake (Crotalus atrox)


Class: Reptilia
Order: Squamata
Family:    Viperidae
Size:    Length: 3 to 6 feet (91 to 180 cm)
Weight: 1 to 2 pounds (453 to 907 g)
Diet: Rodents, frogs, lizards and birds
Distribution: Southwestern USA
Young:  2 to 24 at one time
Animal Predators:  Birds of prey, skunks and other snakes
IUCN Status: No special status
Terms: No special terms
Lifespan: Up to 25 years



·         Rattlesnakes shed their skin one to four times a year.

·         Rattlesnakes are deaf.

·         Rattlers hibernate during winter because they are unable to digest food in cold weather.

·         The eastern diamondback of southeastern U.S. is even larger than the western diamondback.

·         Rattlesnakes in the wild only eat every two to three weeks.



With their plump body, short tail and large triangular head, western diamondback rattlesnakes are one of the largest rattlesnakes in the world. When confronted or startled, these snakes coil and rattle their tail, producing a rhythmic nose similar to that of a baby’s rattle. The rattlesnakes’ hollow fangs lie folded up along the roof of their mouth when the mouth is closed, but they swing down into place when needed. Western diamondbacks have lidless eyes that are protected by the outer skin. Rattlesnakes shed their skin one to four times per year. As the snakes age, new rattles are formed with each molt while old rattles simultaneously fall off. Their name comes from the diamond-shaped pattern along their back. 



Diamondbacks live in warm climates of the Southwest United States—deserts, semi-desert grassland or rocky canyons, especially where rodents are abundant. A temperature range of 70 to 95°F (21 to 35°C) is preferred, because snakes cannot survive in temperatures lower than 65°F (18°C). During the winter months, several snakes hibernate together for warmth. When not active, they spend their time in rocky crevices or in abandoned underground burrows.


Feeding Habits

Western diamondback rattlesnakes have pits on the sides of their heads that work as heat sensors to help detect prey such as rodents, frogs, lizards and birds, even in complete darkness. After biting their victims, rattlesnakes recoil and wait for the venom to go to work. Rattlesnakes swallow their prey whole, then digest the food as it passes through the body. 



When the female is ready to mate, she initiates the act by releasing a scent. The male will follow the scent to the female and cuddle beside and on top of her, nudging her with his head. The female produces eggs that stay in her body until she is ready to give birth. The young, usually between four and 12, pierce their thin membranes immediately before birth and are born alive, sometime between August and October. The offspring measure from six to eight inches (15 to 20 cm), are able to fend for themselves from birth, and are able to attack prey within minutes. Rattlesnakes reach maturity at age three.



Rattlesnakes usually come out at night, and they can be aggressive and excitable when they are provoked or threatened. However, when left alone, they do not attack and avoid confrontation. 



Snakes are not well liked due to public fear but they are actually an important link in the ecosystem, keeping rodent populations in control. Western diamondback rattlesnakes have high reproduction rates and their population is in no danger at this time. 










Western Diamondback Rattlesnake Wildlife Fact File, IM Pub, US