NATURAL HISTORY

EASTERN MASSASAUGA } Sistrurus catenatuscatenatus
FAMILY: Viperidae

DESCRIPTION: Massasaugas are small snakes with thick bodies, heart-shaped heads, and vertical pupils. The average length of an adult is about two feet. Adult massasaugas are gray or light brown with large, brown blotches on the back and sides. Their tails have several dark-brown rings and are tipped by gray-yellow, horny rattles.

HABITAT: Massasaugas live in wet areas including wet prairies, marshes, and low areas along rivers and lakes. They often hibernate in crayfish burrows, but they may also be found under logs and tree roots or in small mammal burrows. Unlike other rattlesnakes, massasaugas hibernate alone.

RANGE: Eastern massasaugas live in an area that extends from western New York and southern Ontario to southern Iowa, as well as on a narrow band of land in northeastern Missouri. Historically, the snake's range covered this same area, but within this area the number of populations — and the number of snakes within populations — have steadily shrunk.

MIGRATION: A local migrant, the massasauga may travel 1.6 miles or more between winter and summer habitats.

BREEDING: Like all rattlesnakes, massasaugas bear live young — the young actually hatch from eggs while still in the female's body. Depending on the health of the individual, adult females may bear young every year or every other year. When food is especially scarce, they may only have young every three years.

LIFE CYCLE: Massasaugas that have young every year mate in the spring and bear their young in late summer or early fall. In contrast, snakes that have young every other year mate in autumn and bear young the next summer. Litter size varies from five to 19.

FEEDING: Massasaugas eat small rodents like mice and voles but will sometimes eat frogs and other snakes. They can find their prey by sight, by feeling vibrations, by sensing heat given off by their prey, or by detecting chemicals given off by the animal.

THREATS: Habitat loss due to urban development and eradication by humans threatens the species.

POPULATION TREND: Massasaugas are in decline.