NON-VENOMOUS

Black Rat Snake Elaphe obsoleta obsoleta

Black Rat Snakes are large constricting snakes. They are weekly keeled to smooth scaled. Adult size is in the range of 42 to 72 inches. Specimens longer than six feet are not rare.

Adult Black Rat Snakes appear shiny black. However, in bright light a faint blotched pattern may be seen. Their chins and throats are white, changing to checkerboard black and white and then to cloudy gray on the belly. Young Black Rat Snakes are strongly blotched against a gray background and could be easily mistaken for a different subspecies. Black Rat Snakes are commonly found throughout South Carolina except in the coastal counties where they are replaced by the Yellow Rat Snake. However, in the summer of 1999 I found a DOR adult Black Snake on US 17 near the bridge over the Pee Dee River at Georgetown. In the upper Coastal Plain region there is much integrading between the Black and Yellow subspecies, resulting in a variety of colors and patterns as evidence by the specimens shown above from Richland County.

Black Rat Snakes are not venomous, but may bite if handled carelessly. Ratsnakes are relatively slow moving and will most often freeze when first encountering danger. This is why so many are killed on our roadways. When freezing while crawling on the ground they will often take on a rippled posture, looking like a large unironed ribbon.

Although most specimens are discovered on the ground, Black Rat Snakes are good climbers. I once observed a specimen raiding a gray squirrel nest high in a tree in November after most leaves had fallen. Rodents, birds and bird eggs, and lizards are favored prey by rat snakes. Rat snakes do ocassionally raid hen houses, eating chicks or eggs. For this reason, they are sometimes called "Chicken Snakes."

Based upon the e-mail inquiries I receive, neonate Black Rats are the most frequently found snakes entering homes, usually in the early Fall or Spring.

September 17, 2007
Contact: South Carolina Reptiles and Amphibians