Just as a precaution, again let me say that yellow rat snakes DO bite when cornered. While they tame down really nicely (and quickly) in captivity, adult rat snakes do NOT want to be caught or cornered and will bite if threatened. Especially the larger ones, and they get VERY large. Over 8 feet in length, making them about the 2nd longest non-venomous snake in the U.S. When cornered, the first thing they will do is curl up and vibrate their tails like crazy. If they happen to be in dead leaves or grass, this will make a sound similar to a rattlesnake. They are warning you to leave them alone. If you persist and reach for them, they will strike like crazy, and having been bitten by a large one, I can tell you, it hurts. (Plus it hurts the snake, as well, since their teeth curve backwards into their mouths and often are broken or pulled right out when they bite a person.) Of course, I was only bitten because I picked a big one up incorrectly and it whipped its head around and nailed me. I should have left it alone! The best rule of thumb for MOST of us is to leave them alone. They don't want to bother you, and won't if you don't bother them. Black racers will strike repeatedly and bite, too, if cornered. But it's been my experience that, unlike the rat snake, they don't make nice pets. They don't like captivity and never seem to become docile. (I'm not saying no one has ever had a tame one, of course. This is just as a general rule.) Anyway, your rat snake is patroling your yard, and he is nothing to worry about. He may startle you from time to time, but he won't attack you if you don't try to pick him up or harm him. Nice pic of the black racer, Heather. I have a couple in this yard but no yellow rat snakes, sadly. That I've seen so far, anyway. The black racers are also doing a great job of yard patrol, and they are welcome here, too. Marcia

Even though Rat Snakes do dine on small mammals I have not heard of one attacking a cat which would be about four times as large as a chipmunk, or more. Also, contrary to some myths, these snakes do not wrap themselves around prey and squeeze as a constrictor would. While they do wrap themselves around tree branches that is to hold on and is not a means of obtaining prey. Here is a link that might be useful: About Rat Snakes

It looks a but thick and not as glossy as a Black rat. Also, Black rats are creamy on the belly. Maybe a Northern water snake?

As long as there is food (rodents, chicks, eggs) you will have snakes. If you let the ratsnake live, it leaves less food available for venomous species.