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Eastern Massasauga Rattlesnake

Eastern Massasauga Rattlesnake
Sistrurus catenatus catenatus

Image of eastern Massasuga rattlesnakeDescription

A heavy-bodied, gray or brown snake with dark blotches and spots on the back and sides. The only Michigan snake with segmented rattles on the end of its tail and elliptical ("cat-like") pupils in the eyes. The neck is narrow, contrasting with the wide head and body. The belly is mostly black or mottled dark gray.

Adult Length:

2 to 3 feet.

Habitat and Habits

The Massasauga is typically a snake of the swamps, fens, and sedge marshlands. They often move to upland fields and woods in summer, probably in search of mice and voles, their favorite food. These rattlesnakes are usually shy and avoid confrontation with humans. They should be treated with respect and always left alone. Any bite from a Massasauga should receive prompt professional medical attention.


Females give birth to 8 to 20 young in late summer. The babies have a single "button" on their tails.

Range and Status

Massasaugas are found in scattered localities throughout the Lower Peninsula, but not in the Upper Peninsula (thus there are NO venomous snakes on the Upper Peninsula mainland.) They are rare or extirpated over most of their known Great Lakes range; considered "threatened" by the USFWS; protected in all states and provinces where they occur.


James Harding
MSU Museum
Michigan State University
East Lansing, MI 48824
(517) 353-7978