This female Northern Water Snake (Nerodia sipedon) is hunting near the edge of a marsh. Northern Water Snakes are found throughout eastern and central North America, from southern Ontario and southern Quebec in the north, to Texas and Florida in the south. They can grow up to 135 cm (4 ft 5 in) in total length. Adult females can weigh up to 408 g (14.4 oz) in average body mass while the smaller males average up to 151 g (5.3 oz). The largest females can weigh up to 560 g (20 oz) while the largest males are 370 g (13 oz).
The northern water snake is nonvenomous but can give a painful bite. They superficially resemble the venomous cottonmouth and are often misidentified. Being active during the day and night, they hunt using both smell and sight. During the day, they hunt among plants at the water's edge, looking for small fish, frogs, worms, leeches, crayfish, salamanders, small birds and mammals. At night, they concentrate on minnows and other small fish sleeping in shallow water.