Project Passenger Pigeon

Lessons from the Past for a Sustainable Future

rattlesnakeMassasauga Rattlesnake



Species Declining, Threatened, Gone, Saved

Massasauga Rattlesnake:
Threatened in the U.S. and Canada

Serves an Important Role in Rodent Control

As historical accounts attest, the massasauga rattlesnake (Sistrurus catenatus) is a species was once common throughout out its range but human activity has reduced populations to the point that it is on many state endangered lists and is being monitored by the US Fish and Wildlife Service for possible future listing on the federal level. It is also listed as threatened in Canada and Ontario, the only province that harbors the species. Making things more difficult for conservationists, the massasauga is one of the most difficult of snakes to see.

Massasaugas play an important role in the ecosystem by feeding on mice, voles, and shrews, thus keeping the rodent population under control. Today we continue to learn more on how each individual part of our precious ecosystem is needed for the entire system to work properly.

The Eastern Massasauga is the most northern rattlesnake in North America. It has a long thing range from Ontario and New York on the northeast to northern Tamaulipas on the southwest with some isolated populations in other parts of Mexico. But because the massasauga is shy and secretive, most people will never see one in the wild. It prefers to hide under brush and thick grasses, and retreats quickly to a sheltered area if spotted in the open. The term, “massasauga” literally translates to “great river mouth,” for the typical, wet habitats that most will find this snake. Though a few will be found moving to and from more upland sites, the majority are in wetland habitats, particularly wet seeps and meadows, fens, and alongside marshes and swamps. All of these areas provide for its slang name, the “swamp rattler.”

When one does find a massasauga, the snake’s pattern can be quite recognizable from other snakes. The body is light to medium brown, with darker brown or black irregular splotches down its entire backside. The traditional pit viper, triangular head is noticeable in most cases, and a close up look also reveals the cat-like, vertical slit iris. Understandably, most will never get close enough to see this. By far its most known feature is the accumulation of beads at the end of the tail, which are added upon each time the snake sheds. These beads collectively become the rattle that the snake uses as a distraction technique for both predators and prey.

Within the Chicago region, most folks will never encounter this small snake. However, like other venomous snakes, the bite is toxic, but injections are only done through small fangs. Unlike one hundred years ago, almost all snakebite victims survive, provided they receive prompt medical attention. Human fatalities from massasauga bites are rare. Knowing the massasauga and its identification marks is important for any outdoors hiker with an interest in herpetology, the study of reptiles.

If you get a lucky chance to see a massasauga, enjoy the observation, from a safe distance.

Pepared by Brad Bumgardner, Naturalist at the Indiana Dunes State Park, Chesterton, Indiana.

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