I am the only venomous snake in Wyoming, but you don’t need to be really afraid of me, because I would rather not bite you. I’d much rather save my venom for the mice, ground squirrels, and birds that I eat. My rattling is meant to warn people to stay away, when they accidentally get too close. I’m a very good rattler–the muscles that I use to shake my rattle are among the fastest in all vertebrates! (You can hear my rattling sound if you click here (http://sdsnake.com/Snake/rattle.wav).)
My babies are born alive and I can have up to 25 young, but most often I have around 12. My babies are very venomous even immediately after they are born, so please do not to pick them up, for both our sakes. We have a pair of hollow fangs to deliver venom. Our fangs fold against the roof of our mouths when we are not using them, but point forward when we strike our prey.

We are shy and secretive. When you approach us we usually remain quiet to avoid being detected or we try to escape. Most people in Wyoming have never seen a prairie rattlesnake, even when they live in snake country: If people knew how many times they have been very close to us, they would never go to many places! But if you frighten us, or corner us, we will stand our ground and attempt to bite. If you leave us alone, we will likely do the same to you.

Rattlesnakes are called pit-vipers because we have a small cavity, or pit, on each side of our head between the eye and nostril. We use these pits to sense our warm prey up to two feet away, even when it is completely dark. Unlike my warm-blooded prey, I am unable to produce my own body heat. To maintain the temperatures that I desire, I rely on the warmth of my surroundings when I am cold and on shady cool places when I am hot. When days get shorter and there is a frost in the air I move to a den on a hillside or rocky outcrop,or sometimes into the burrows of prairie dogs. There I spend the winter, sometimes sharing my den with hundreds of snakes, all sleeping and hanging out together. In the spring, when temperatures increase, we abandon the den and may travel long distances to find food and mates, and to have our young. But we are faithful to our dens and will return in the fall. We have a very good sense of direction!