NON-VENOMOUS

Other common names

Brown Water Snake

Basic description

Most adult Brown Watersnakes are about 30-60 inches (76-152 cm) in total length. These stout-bodied snakes are light tan with squarish darker brown blotches down the middle of the back. Dark squarish markings also extend upwards from the belly onto the sides of the body between the blotches on the back. The head is large and distinct from the neck. Juvenile coloration is similar to that described for adults.

Range in Florida

Brown Watersnakes are found throughout mainland Florida in every county. However, they are absent from the Florida Keys.

Assessment of risk to people and pets

Non-venomous. Brown Watersnakes are not dangerous to people or pets, but they will readily bite to defend themselves. These snakes are not aggressive and avoid direct contact with people and pets. Virtually all bites occur when the snakes are intentionally molested.

Comparison with other species

Florida Cottonmouth (Agkistrodon conanti) Venomous If the head is viewed from above, the eyes of cottonmouths cannot be seen while the eyes of watersnakes are visible. Cottonmouths have vertically elliptical (cat-like) pupils, whereas watersnakes have round pupils. Cottonmouths have a facial pit between the nostril and the eye, whereas watersnakes do not.

two images side by side - Image 1: Eastern coachwhip - snake with its head raised above the grass. Image 2: Florida Cottonmouth - coiled snake with its head raised.
Florida Cottonmouth. Photo courtesy of Luke Smith.
Adult Brown Watersnake. Photo courtesy of Todd Pierson.

Saltmarsh Watersnake (Nerodia clarkii) Non-venomous Saltmarsh Watersnakes often have several dark stripes running down the entire or partial length of the body, and they are usually only found along the coast in saltwater and brackish habitats.

two images side by side - Image 1: Saltmarsh watersnake - thin brown snake with pale stripes. Image 2: Adult brown watersnake - coiled brown snake with dark brown markings.
Saltmarsh watersnake. Photo courtesy of Luke Smith.
Adult Brown Watersnake. Photo courtesy of Todd Pierson.

Florida Green Watersnake (Nerodia floridana) Non-venomous Florida Green Watersnakes are dark green and have scales between the eye and the scales on the upper lip.

two images side by side - Image 1: Florida Green Watersnake dull green snake in marsh grass. Image 2: Adult brown watersnake - coiled brown snake with dark brown markings.
Florida Green Watersnake. Photo courtesy of johnjinjohny/iNaturalist
Adult Brown Watersnake. Photo courtesy of Todd Pierson.

Midland Watersnake (Nerodia sipedon pleuralis) Non-venomous Midland Watersnakes have fewer than 30 darker brown crossbands near the neck, which break up into alternating blotches further down the body, and the belly is yellowish marked with two rows of half-moons.

two images side by side - Image 1: Midland Watersnake - small patterned snake on pavement. Image 2: Adult brown watersnake - coiled brown snake with dark brown markings.
Midland Watersnake. Photo courtesy of hunterewgley/iNaturalist
Adult Brown Watersnake. Photo courtesy of Todd Pierson.

Southern Watersnake (Nerodia fasciata) Non-venomous Southern Waternsnakes have broad black, brown, or red crossbands (often bordered with black) down the back and a dark stripe that extends from the eye to the angle of the jaw.

two images side by side - Image 1: Southern Watersnake coiled snake with raised head. Image 2: Adult Brown Watersnake - coiled brown snake with dark brown markings.
Dark adult Southern Watersnake performing defensive head flattening. Photo courtesy of Luke Smith.
Adult Brown Watersnake. Photo courtesy of Todd Pierson.

Share your observations

You can help scientists better understand the biology and distribution of this species by sharing your observations. Send photos or videos of interesting observations, along with associated information, by emailing the herpetology staff at the Florida Museum for documentation in the Museum’s Herpetology Master Database. You can also post your observations on iNaturalist.

Additional helpful information

Do you have snakes around your house? Learn how to safely co-exist with snakes.

Still have questions about snakes or identifications? Feel free to email the herpetology staff at the Florida Museum with your questions or feedback on this profile.

Banner photo courtesy of Todd Pierson. Please credit any photographers on the page and see our copyright policy.