Quick Reference Guide: Native Snakes Easily Mistaken for Introduced Constrictors in Florida1
Three non-native species of large constrictor snakes are now breeding in Florida, and several others have been encountered but have not yet established wild populations. This fact sheet, best viewed as a pdf (https://edis.ifas.ufl.edu/pdffiles/UW/UW35000.pdf), is a quick reference guide to identification of the native snakes you might easily mistake for introduced constrictors in Florida. Like the introduced constrictors, these similar native snakes are large, aquatic, or have blotched markings. It is important to learn to recognize these native snakes so that you do not report them via the EDDMapS Florida invasive species reporting portal online at http://www.IveGot1.org. Learn more about how to scan for, recognize, and report introduced constrictors by completing the Introduced Reptile Early Detection and Documentation training course. Visit http://ufwildlife.ifas.ufl.edu/reddy.shtml to learn more and get REDDy!
Large Native Snakes
Eastern Indigo Snake (Drymarchon couperi)
Status: rarely encountered
Size: up to 8 feet
Head: reddish marks on chin
Body: iridescent blue-black with no markings
Credit: Monica E. McGarrity, UF
Eastern Diamondback Rattlesnake (Crotalus adamanteus)
Status: venomous, occasionally encountered throughout Florida
Size: up to 6–8 feet
Head: blocky, dark eyestripe with cream borders, vertical pupil
Body: dark diamonds with cream borders
Credit: Monica E. McGarrity, UF
Aquatic Native Snakes
Cottonmouth or Water Moccasin (Agkistrodon piscivorus)
Status: venomous, common throughout Florida
Size: usually 2–4 feet
Head: blocky, dark eyestripe, vertical pupil
Body: blotched bands, older individuals may be solid black
Credit: Monica E. McGarrity, UF
Brown Watersnake (Nerodia taxispilota)
Status: common throughout Florida
Size: usually 2–4 feet
Head: top unmarked, yellow flecks on chin
Body: squarish dark blotches in a "checkerboard" pattern
Credit: Monica E. McGarrity, UF
Blotched Native Snakes
Cornsnake or Red Ratsnake (Pantherophis guttatus)
Status: common throughout Florida
Size: usually 2–3 feet
Head: reddish arrowhead
Body: reddish blotches with dark outlines, checkerboard pattern on belly
Credit: Monica E. McGarrity, UF
Acknowledgments
This project was made possible in part by a grant from the South Florida National Parks Trust and the Ferris Greeney Family Foundation, and by the USDA-RREA. This document was originally created as additional reference material for the Introduced Reptile Early Detection and Documentation training program, also known as REDDy. For more information, visit http://ufwildlife.ifas.ufl.edu/reddy.shtml.
