Prairie Rattlesnake
Crotalus viridis

distribution map of Crotalus viridis

Rock Rattlesnake

Crotalus viridis. Photographer: Dr. Carl S. Lieb. Ca. 12 km (air) N Lordsburg, NM, ca. 4500 ft elev.


Physical Characteristics

Total length of adults is 35-45 in. (89-114 cm). Overall ground color is usually yellowish brown, but may be greenish gray, olive-green, and greenish brown. Brown, ovoid blotches occur along the back and usually narrow near the tail to form brown crossbands. There are two oblique light lines on the head, with one beginning just behind the eye and extending just above the corner of the mouth.

Geographic Range

Western North America from southwest Canada south to Coahuila, Mexico. Elevation ranges from sea level to around 11000 ft. (3350 m).


Crotalus viridis is known to frequent a multitude of different habitats, including desert, grassland, shrubland, woodland, and pine forest. Within these areas they occur anywhere from outcrops and talus slopes to rocky washes and caves. In the El Paso region, this species is associated with grasslands and desert grasslands.


The Prairie Rattlesnake feeds on mammals (mice, rats, squirrels, rabbits), but will also consume lizards, nestling birds, snakes, and amphibians.

Reproductive Characteristics

Live-bearing. Birth usually occurs August to October, with brood size averaging 1-25 (often 4-12). Newborns are generally 8.5-11 in. (22-28 cm) in length.


The form of the western rattlesnake that occurs in the El Paso area is the Prairie rattlesnake, a subspecies that occurs throughout the Great Plains of the U.S. According to many writers of our past, this is the rattler that was known to live harmoniously with prairie dogs and burrowing owls. Quite the contrary, to the common Prairie Rattler, they are truly a satisfying meal.


Kinniburgh, R. M. 1972. Distribution of Thermal Responses of the Rattlesnake (Genus Crotalus) in El Paso County, Texas. University of Texas at El Paso.

Klauber, L. M. 1982. Rattlesnakes. University of California Press, Berkeley.

Stebbins, R. C. 1985. A Field Guide to Western Reptiles and Amphibians. Houghton Mifflin Company, Boston.

Tennant, A. 1985. A Field Guide to Texas Snakes. Texas Monthly Press, Hong Kong.

William D. Beltran, July 1997.


Last Update: 11 Jul 2009