Common Name: Yellow-bellied water snake Scientific Name: Nerodia erythrogaster Identification: 16-45 in. Dark gray-green back: yellow belly. Young snakes of this species are marked like other water snakes: pale with large, squared alternating blotches. Scales keeled. Habits: The yellow-bellied water snake is less aquatic than other water snakes and may be found some distance from water in wooded areas. Distribution: Throughout Louisiana. Comments: The yellow bellied snake also resembles the poisonous water moccasin, but is non-venomous and therefore harmless.