Yellowbelly Water Snake



Scientific name: Nerodia erythrogaster flavigaster (CONANT 1949)
* Currently accepted name

* scientific names used through time

  • Coluber erythrogaster – FORSTER 1771
  • Tropidonotus erythrogaster – HOLBROOK 1842
  • Nerodia erythrogaster – BAIRD & GIRARD 1853
  • Natrix sipedon erythrogaster – ALLEN 1932
  • Natrix erythrogaster – BURT 1935
  • Natrix erythrogaster flavigaster – CONANT 1958
  • Nerodia erythrogaster flavigaster – CONANT 1949

Description: Average adult size is 30-48 inches (76.2-121.9 cm), record is 59 inches (149.8 cm). Adults are heavy-bodied, greenish gray in color with faint to no markings on the back. The belly, neck, and labial scales are almost uniform yellow. The scales are keeled, and there are 23 dorsal scale rows at midbody. The pupil is round. Juveniles are grayish-brown with distinct dark crossbands and blotches, with pale yellow bellies.


A. Top of the head
B. Underside of the head (chin and throat)
C. Elongated scales below the tail (subcaudal scales) are typically divided
D. Front (face view) of the head
E. Side of the head
F. Keeled scales

Range: In Florida, it is found throughout the western panhandle where it intergrades (interbreeds) with the Redbelly Water Snake (Nerodia erythrogaster erythrogaster). Outside of Florida, it is found from eastern Texas east to central Georgia and north to Illinois.

Habitat: Commonly found in rivers, lakes, ponds, swamps, and cypress strands.

Comments: HARMLESS (Non-Venomous). The Yellowbelly Water Snake is active mainly during the daytime. During the hot summer months it is active in the early morning, late afternoon, and at night.

It feeds on fishes, frogs, tadpoles, other amphibians, and inverbrates. It is live-bearing, newborns are 9-12 inches (22.8-30.4 cm) in length.

Comparison with other species: The Mississippi Green Water Snake (Nerodia cyclopion) and Florida Green Water Snake (Nerodia floridana) have scales between the eye and the scales on the upper lip.

Because they are found around water bodies, harmless Water Snakes are often confused with the venomous Cottonmouth (Agkistrodon piscivorus). The Cottonmouth has a triangular shaped head and vertical pupil. Cottonmouths can easily be distinguished from Water Snakes. If the head is viewed from above, the eyes of Cottonmouths cannot be seen while the eyes of Water Snakes are visible; Cottonmouths have elliptical pupils and Water Snakes have round pupils; Cottonmouths have a facial pit between the nostril and the eye, while Water Snakes do not.