Identification of the Cottonmouth Snake

Color and Pattern

• The cottonmouth snake is normally grey in color with dark brown bands, and has a light beige-colored belly. Water snakes also display a similar coloration and pattern, however older cottonmouth snakes can be distinguished from water snakes easier, as their pattern turns darker over time. A mature adult cottonmouth snake may appear to be solid black or dark brown, with only a hint of the banding pattern visible near the sides of its body where it is lighter in color.

Head and Eyes

• Cottonmouth snakes have a pointed nose and arrowhead-shaped head. The head is much larger than the thickness of the snake's neck, while nonvenomous snakes often have a uniform head and neck thickness. When the mouth is open, large fangs can be observed at the front. Similar-looking nonvenomous snakes do not have these fangs and may appear to have no teeth at all, although they do have very tiny rows of teeth. Cottonmouths, like most venomous snakes, have thin, slit-like pupils instead of round ones.

Scales

• Cottonmouth scales are keeled, which means they are triangular-shaped and have a thick ridge running down the center. These keeled scales give the cottonmouth snake a spiky looking appearance. On the underside of the snake, the end of its tail has one single row of scales, whereas the anal region of nonvenomous scales has two. The cottonmouth snake does not have a rattle like most venomous snakes in the southern United States.

Behavior

• The cottonmouth snake is known for its aggressive nature and, when provoked, may curl up and tilt its head back, opening its mouth to show off its fangs. Most other snakes try to escape if they feel threatened. The cottonmouth swims on top of the water with its head fully out of the water, whereas other snakes swim low in the water.