Solid black melanistic examples are also known, as well as cases where the back blotches join with those on the sides.

[12] S. catenatus is found in North America from Ontario, Canada and central and western New York throughout the Great Lakes region to the Midwest.

[13] The eastern massasauga is listed as an endangered species in Illinois, Indiana, Iowa, Minnesota, Missouri (also considered extirpated), New York, Ohio, Pennsylvania, and Wisconsin.

Historically, this has been due to human activity and more recently primarily from natural forest succession.

In general, however, frogs are not an important part of the diet, although this does seem to be more typical in certain northern and eastern populations.

After envenomation, the rattlesnake is able to withdraw from the dangers of sharp-toothed prey animals until they are subdued and even partially digested by the action of the venom.

Most massasauga snakebites in Ontario have occurred after people deliberately handled or accidentally stepped on one of these animals.

[citation needed] Both of these scenarios can be prevented by avoiding hiking through areas of low visibility (in rattlesnake country) when not wearing shoes and long pants and by leaving the snakes alone if encountered.

Only two incidents of people dying from massasauga rattlesnake bites in Ontario have been recorded; in both cases, the victims did not receive proper treatment.