The Reptiles and Amphibians of Arizona

Online Field Guide to The Reptiles and Amphibians of Arizona

Massasauga (Sistrurus catenatus) Arizona
Cochise County, AZ

Cochise Co., AZ

MASSASAUGA Sistrurus catenatus

Venomous

DESCRIPTION: A small (up to 550 mm or 22″ in total length excluding rattle) light silver-gray to gray-brown rattlesnake. Large, oval, crisp-edged, dark brown blotches line the back. A row of faded, soft-edged blotches lines each side. Below that row there are two additional rows of crisp-edged, dark gray-brown blotches. A crisp dark brown bar bordered by a thin white lower-edge extends back from each eye. The top of the head is marked with two wavy, dark brown, elongated blotches that extend back onto the neck. Young have a yellow tail that is used to lure lizards. The underside is usually plain cream or white. The top of the head is armored with large plate-like scales. The pupils are vertically elliptical and the dorsal scales are keeled. The neck is slender and the head is broad and triangular. On the end of the tail is a rattle composed of a series of loosely interlocking keratinous sections. A new section is added each time the snake sheds its skin. The rattle is very small relative to the body size.

DISTRIBUTION: This snake’s range appears to be shrinking in Arizona. Some historic Arizona populations are likely extirpated. The species remains in only a few isolated populations in the extreme southeastern portion of the state. In Arizona it is found at elevations ranging from about 3,500′ to about 4,600′.

HABITAT: In Arizona this snake is found in valleys, on low sloping bajadas, and on rolling grass-covered hills within the Semidesert Grassland community.

BEHAVIOR: It is primarily nocturnal, but is occasionally encountered on the surface in the morning, on overcast days, or just before sunset. It spends most of it’s time underground in rodent burrows. It hibernates during the cold months of late fall and winter.

DIET: The Massasauga eats lizards, centipedes, mice, and other small mammals. It uses venom injected through long, hollow, retractable fangs to kill and begin digesting its prey.

REPRODUCTION: A litter of 4 to 8 young is born in late summer.

REMARKS: This rattlesnake is capable of delivering potent venom. If encountered it should be left alone. A large percentage of envenomations occur when a snake is handled or abused. Protected in the state of Arizona. It is against Arizona State law to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect this animal or to attempt to engage in any such conduct.

By Thomas C. Brennan

Bartlett. 2000. Snakes of North America: Western
Region. Gulf Publishing Co. Houston, TX

Brennan, T. C., and A. T. Holycross. 2006. A Field Guide to Amphibians and Reptiles in Arizona. Arizona Game and Fish Department. Phoenix, AZ

Degenhardt, W. G., Painter, C. W., and Price, A. H.. 1996. Amphibians and Reptiles of New Mexico. University of New Mexico Press. Albuquerque.

Fowlie. 1965. The Snakes of Arizona. Azul Quinta Press, Fallbrook, California

Lowe, Schwalbe, Johnson. 1986. The Venomous Reptiles of Arizona. Nongame Branch
Arizona Game and Fish Department. Phoenix, AZ

Stebbins. 1985. Western Reptiles and Amphibians. Houghton Mifflin. New York, NY

Massasauga (Sistrurus catenatus) Arizona Range Map

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