What Does A Black Racer Snake Look Like And Is It Poisonous?

The Southern Black Racer (Coluber constrictor priapus) is usually thin with a jet-black dorsal side with a grey belly and white chin. They are quite fast, giving rise to the name "racer". The Racer is the only large, black snake in New England, USA, with smooth scales. It's chin, throat and jaw are white or grey, and the belly is generally dark (with mixtures of grey, blue, or black) from the throat back to the tail. Smooth scales give this snake a silky or satin-like appearance.

A juvenile racer is grey with large brown, black or reddish blotches down the back, small spots along the sides and large dark eyes. The pattern fades with age however, disappearing when the snake reaches 25-30 inches in length. Racers are very fast movers, and typically flee when threatened, or in danger. On some occasions, they will put up a strong fight when cornered, biting hard and often. The Racer's small sharp teeth can deliver a painful, but non-venomous, bite.

Rattling their tails among dry leaves, racers can sound convincingly like rattlesnakes, and have mistaken often because of this. If captured, they are very difficult to handle as they will writhe, defecate and spray musk in an attempt to escape. Black Racers are diurnal (daylight) hunters, and are very much active in the daylight hours. They eat rodents, birds, frogs, lizards and insects. Small mammals, other snakes and insects are preferred food items, although Racers take a wide variety of prey. They will even feed on young of their own species.

The poor thing. It sounds like a racer, which is a constrictor, and isn't poisonous. You can type in racer snakes in the google search bar, and then, when you get to it, click on images. You should be able to find it in there. Hope this helps, good luck.

Black racers are solid black. 
 
The Eastern Mud Snake is Black, with a checkerboard belly of black and pinkish to white scales. Can grow to 6-1/2 feet.  Usually found near swamps, lakes, streams.  Highly aquatic.
 
The Black Rat Snake is nearly full black in the back, but may show some white speckles, whereas its chin and belly have a lot of white markings.  One way to distinguish this from the mud snake is it generally has a slightly raised ridge of scales down it's middle.  These climb trees, and generally feed on rodents, birds, and bird eggs.  They also grow to more than 6 feet.
 
If it had an orange belly, it would be the Black Swamp Snake.
 
Whichever breed it is, I think you have a juvenile if it is farily small , due to the lighter marking on the back.