Ontario Rattlesnakes and Their Mimics
Rattlesnakes in Ontario are largely harmless, save for the Massasauga rattlesnake, the only venomous one in the province.
Rattlesnakes are not the demons many of us perceive them to be. In Ontario, death by rattlesnake is almost as rare as death by meteorite. Only two documented deaths have been recorded in the province, both over four decades ago. Importantly, neither victim sought medical care.
Massasauga rattlesnakes are the only species of venomous serpent that remain in Ontario. Timber rattlesnakes have vanished, victims of human fear and habitat loss. Massasauga rattlesnakes are now restricted to the Georgian Bay area and a tiny outpost on the Niagara Peninsula. They continue to inspire fear where they persist, and this fear, regrettably, extends to non-venomous snakes, even in locations far from rattlesnake country.
Throughout North America, many harmless species of snakes have evolved to mimic rattlesnakes. The evolutionary advantage is clear. Predators that recoil from rattlesnakes will also recoil from them.
In Ontario these rattlesnake mimics include eastern foxsnakes, milksnakes and eastern hog-nosed snakes. Only one, the milksnake, slithers through Headwaters. These harmless snakes have colours and patterns similar to rattlesnakes, but that convergence may have simply arisen from the need to conceal themselves in similar habitats. It may not have anything to do with mimicry.
The clear – and fascinating – mimicry is behavioural. Foxsnakes, milksnakes and hog-nosed snakes all vibrate the tips of their tails when alarmed. In grass or dry leaves, a rustling sound is produced, evoking the warning buzz of rattlesnakes.
Though rattlesnake mimicry has likely served these snakes well for millennia, it is now dysfunctional in areas where Homo sapiens dominate. While many wild predators will back off when the tails of these snakes vibrate, many people respond with aggression, killing the snakes with the nearest rock or shovel.
If you fear serpents, please understand that all Headwaters snakes are harmless. And know, too, that even in the parts of Ontario where massasaugas persist, the risk to life and limb is very, very small.