Michigan is home to the Eastern Massasauga Rattlesnake ( Sistrurus catenatus ), its only native venomous snake species.
Michigan’s Only Native Rattlesnake
The Eastern Massasauga Rattlesnake is a small to medium-sized pit viper, typically 2 to 3 feet long. It has a thick body, a triangular head with vertical pupils, and is usually gray or light brown. Its coloration features large, light-edged chocolate brown to black blotches along its back and smaller spots on its sides; some individuals may appear almost entirely black.
A distinguishing characteristic is the keratinized rattle at the end of its tail, used to deter threats. The Massasauga’s rattle sounds like a buzzing insect, distinct from the louder rattles of other species. Despite being venomous, these snakes are shy and prefer to avoid human interaction, often relying on camouflage or attempting to flee when disturbed.
Where They Are Found and Why
Eastern Massasauga Rattlesnakes are primarily found in Michigan’s Lower Peninsula. They thrive in various wetland environments, including bogs, fens, shrub swamps, wet meadows, marshes, and moist grasslands. They also use adjacent upland areas like forest openings, old fields, and prairies, especially in summer.
These habitats offer essential resources like food and hibernation sites. Massasaugas often hibernate alone in crayfish burrows, small mammal burrows, or under logs and tree roots, typically in lowland areas where groundwater does not freeze. Michigan holds more populations than any other state or province within its range, making it a stronghold for the species.
Safety and Coexistence
Encountering an Eastern Massasauga Rattlesnake is rare due to its shy nature. If encountered, maintain a safe distance and avoid provoking it. Most snake bites occur when individuals attempt to handle or harm the snake. The Massasauga’s venom is potent, but bites to humans are uncommon, and the snake may not inject venom in every bite.
To reduce encounters, stay on designated trails and wear closed-toed footwear. Always be aware of your surroundings and avoid placing hands or feet into areas you cannot see. If you hear a rattle, stop, locate the snake, and slowly move away to give it space. These threatened snakes are legally protected, making it illegal to harass, capture, or kill them.