Alex,
The most common snakes in Chester County are Eastern Garter Snakes,Dekay's and Northern Black Racers. You MIGHT get lucky and see a black rat snake but they are very few of them in the area.
Garter snakes will musk,bite and thrash when handled. They are a generally small snake only getting to around 2-3 feet in length with 3 feet being a big one. The older ones are generally dark on color in this area and are usually almost black/grey with yellow markings which is why almost everyone on here thinks you seen a garter snake. They feed on earthworms,slugs,toads,frogs,salamaders and small fish.
Dekay's otherwise known as the brown snake are small snakes with the average size being 8-12 inches.These are docile snakes and will never attempt to bite.They eat small worms,slugs and snails.
The northern black racer is an extremely aggressive snake and can get up to 5 feet in length. These guys are one of the fastest snakes in the world which is why they are called racers. This is the most aggressive snake in our area and if you encounter one they will bite the hell outta you! They will also latch on to you and chew. These guys can give some nasty bites! They are all black with a white chin and eat just about anything they can fit into their mouth!
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Reptiles
0.1 - Early 2002 Anery Motley Corn 33 1/2"
1.0 - Late 2003 Yellow Rat Snake 15 2/3"
0.0.1 - 2003 Banded California King Snake 29 2/3"
1.0 Green Anole
0.0.0 House Gecko
0.1 Painted Turtle
Mammals
4 female ferrets,1 male cat and 1 male doberman...and a few kids!
RIP - Nala my Rottie 08/19/2004