Asked July 26, 2017, 5:40 PM EDT
Okaloosa County Florida
This species has dark crossbands that extend the entire body length versus the Northern watersnake (Nerodia sipedon) which has crossbands at the front portion of the the body, but then, towards the middle and extending to the end of the body, the crossbands break up into three alternating rows of blotches. Juvenile markings tend to be brighter and more distinct than those of adults. As adults age, some individuals become very dark, and are often misidentified as the venomous cottonmouth (Agkistrodon piscivorus). The typical length of this species is 2 - 3 feet. Maximum reported length is close to 4 feet. In areas where their range overlaps with the Northern watersnake they routinely interbreed with this species.
This species is common in all types of aquatic habitats, but usually most common in marsh areas and ponds. They have a varied diet, feeding on fish, frogs, tadpoles and salamanders.
When threatened watersnakes will first try to escape to the water. If this is not possible, they will flatten their heads and front portion of their body to make themselves appear larger and discharge a strong-smelling musk from their anal glands. If you get closer, they will begin to strike repeatedly. If you get too close or pick them up, they will bite repeatedly, often slash sideways resulting in torn flesh.
I have attached a photo of a juvenile copperhead (Agkistrodon contortrix), so you can see the difference in pattern and coloration.
Here are some excellent field guides for snakes in your area, if you're interested in learning more:
Gibbons, W. & Dorcas, M. (2015). Snakes of the Southeast. Athens: The University of Georgia Press.Gibbons, W. (2017). Snakes of the Eastern United States. Athens: The University of Georgia Press.
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