Massasauga   Sistrurus catenatus

This small rattlesnake is a pit viper and as such, has a heat-sensitive pit on each side of the head between the eye and the nostril. Its head is flattened and much wider than the neck, giving it just a hint of the typical viperidae, triangular-shaped head. The pupil of each eye is vertically elliptical. A rattle is present at the tip of the tail.  The body is gray with a row of dark blotches is present down the back, plus an additional three rows of dark spots on the sides. Scales are keeled (ridged).

The massasauga lives in wet/floodplain prairies, peatlands and old fields. This snake is active in the day, except in the hottest summer months when it becomes nocturnal. The massasauga may take shelter in crayfish burrows or other underground cavities. It may be seen basking on grass, near crayfish burrows or in other open locations. If disturbed it may shake its rattle. The rattle is developed as the skin is shed. A button at the tip of the tail is present at birth then each time the skin is shed, a new segment is added to the rattle. The snake may shed its skin from three to five times in a year. Counting segments of the rattle is not a good method of aging a snake as the number of segments added each year varies, and segments may be broken or lost.

Mating may occur in spring or fall. Females mature after three to four years and reproduce every other year. The female gives birth to five to 14 young in August or September, the number depending on her size and age. This snake eats mice, small birds, frogs and snakes.

The Park's rattlesnakes were confiscated by the Illinois Department of Natural Resources and following the court cases, they were placed at the Park.