Snakes are some of the most misunderstood and mistreated animals in the world. I think it is safe to say that when most people are asked what animal they are afraid of, snakes are at the top of the list. This is unfortunate considering the ratio of venomous to nonvenomous snakes the average human will encounter in their life.

Throughout the US, there are something like 129 different species of snakes, but only 21 are venomous. Here in Pennsylvania we have 21 species, with only 3 being venomous. In this post I am going to share the most common snakes you will encounter and how to determine whether they are venomous or not.

For the venomous side of things, the snakes you may observe are various species of rattlesnake, the cottonmouth(water moccasin), the copperhead, and the coral snake. All except the coral snake are considered “pit vipers” which means that they have heat sensing “pits” between the eyes and nostrils on either side of their head. When determining whether a snake is dangerous or not, all pit vipers have the same characteristics. Aside from the pit(because nonvenomous species like pythons and boas also utilize heat sensing pits), look for a very thick body, large head, and oblong or cat-like eyes.
The coral snake is actually the most venomous snake in North America and follows none of the traditional rules. It is slender, no pits, and has round eyes. There a few species that try to mimic the coral snake, like the scarlet king snake. There are mnemonic devices to help sort it out: “red on black, won’t hurt jack; red on yellow, kills a fellow” is the one i learned growing up.
I have only ever come across the cottonmouth(accidentally caught one as a kid, thinking it was a water snake…oops), and the copperhead. Call me crazy, but I have always wanted to see a rattlesnake and especially a coral snake in the wild.
When it comes to your cuddly nonvenomous pest control snakes, there are quite a few that are commonly found, and it depends on where you live.

Growing up in South Carolina, the most common snakes I found were corn snakes, green snakes, garter snakes, water snakes, king snakes, rat snakes, black racers and pine snakes. For a full list of SC snakes, check out this resource.

Here in Pennsylvania, you may readily spot the Eastern garter snake, Northern water snake, Eastern rat snake, Northern ring-necked snake, Northern red-bellied snake, Eastern milksnake, Northern brown snake, and the Northern black racer. There are several other species which are less common and are either endangered or species of special concern. I have only had the pleasure of encountering the garter and water snakes but am looking forward to finding some of the others. For a full list of Pennsylvania snakes, with pictures and useful information, check out the PA Herps page.
Hopefully this will help you to determine whether the snake in your backyard is worth fussing over. If they look like the ones I have pictured or don’t meet any of the venomous guidelines, please let it be, they are there to help!
Until next time, happy herping, ya’ll!