Thank you for your question. The snake in your photograph is a cottonmouth, scientific name Agkistrodon piscivorus. Alabama has one subspecies, the western cottonmouth, A. p. leucostoma, and two intergrades. Intergrades are the result of the mating between two subspecies. Alabama has an eastern x western cross and an eastern x Florida cross. The exact identity of your cottonmouth is difficult to establish from just a photo. The cottonmouth is a venomous species.

Typical length is approximately two feet, and maximum length can reach approximately four feet. They are found from Virginia south to Florida and west to Texas. They can be found in river swamps, backwaters and floodplains. They are also common in lakes, reservoirs, ponds, streams and wetlands.

They have a varied diet that includes small mammals, birds, fish, frogs, salamanders, other snakes and occasionally baby alligators.

Local snake lore indicates that this species is very aggressive towards humans, but scientific research has shown that this is not the case, and, in fact, most cottonmouths are reluctant to bite. Nevertheless, they should be enjoyed from a safe distance. There common name comes from a defensive threat display in which the snake throws open its mouth, revealing the white lining of the mouth.

If you'd like to learn more about snakes in Alabama, here is an excellent field guide:

Gibbons, Whit. (2017). Snakes of the Eastern United States. Athens: University of Georgia Press.

I hope this answers your question, and thank you for contacting Ask an Expert.

Jim