Timber rattle snakes.

Allegedly we got some poisonous snakes here called Timber Rattlers. I’ve heard about them my whole life, never saw one or met anyone who did.
What I want to know is, how the heck does a cold blooded snake survive here? Especially in winter.

In Wisconsin, timber rattlers hibernate between November and April, staying in dens in rocks. They are somewhat rare (endangered in Wisconsin) and their habitat and habits make them hard to find. They can reach 4 feet in length.

Timber Rattlesnake

They are sometimes confused with the Eastern Massasauga rattlesnake which is also endangered in Wisconsin, but more common other places. I have seen these in northern and southern Illinois.

Massasauga