Eastern Massasauga
Eastern Massasauga (Swamp Rattlesnake)
(Sistrurus catenatus)

Interesting facts:
If a massasauga snake is cornered, it may throw itself into a coil and shake its rattle.

The eastern massasauga ranges in size from 17 to about 40 inches in length. It is heavy-bodied, with several rows of dark brown or gray splotches down the back and sides. It has a rattle on its tail, and it is poisonous. The body color is gray or light brown. Two splotches on the head form stripes. This coloration is protective because it resembles the colors of its surroundings.

Habitat and behavior:
The eastern massasauga occurs in bogs, wooded areas, prairie marshes, and old fields. They rest under rocks, logs, and brush, or in other animals' burrows. The snakes breed in the spring and give birth to 5-24 live young, each about six inches long. Massasaugas hibernate alone in borrowed burrows or under rocks in the winter. They seem to prefer being near water.

They prey upon small mammals, reptiles, amphibians, and probably birds.

Distribution and status:
In Illinois, this endangered species is found in scattered colonies in marshy land. It once occurred in the northern four-fifths of the state, but intensive farming has decreased its habitat.

Colonies have been found in recent years in Clinton County in southern Illinois, Piatt County in east central Illinois, Knox County in western Illinois, and DuPage, Cook, and Will counties in northeast Illinois.