The northern water snake (Nerodia sipedon sipedon) is largely aquatic and riparian. It ranges from Maine and southern Quebec to North Carolina. It also inhabits the uplands of western North Carolina and adjacent portions of Tennessee and Virginia, and its range extends west to eastern Colorado (Conant and Collins, 1991). The northern water snake is typically 61 to 107 cm in total length (Conant and Collins, 1991). Island populations of the species tend to be larger than mainland ones (King, 1986).
The northern water snake prefers streams but can be found in lakes and ponds and nearby riparian areas (King, 1986; Smith, 1961). They are absent from water bodies with soft muddy bottoms which may interfere with foraging (Lagler and Salyer, 1945).
Northern water snakes consume primarily fish and amphibians and, to a lesser extent, insects and small mammals (Raney and Roecker, 1947; Smith, 1961). Diet varies according to the age (and size) of the snake and food availability (DeGraaf and Rudis, 1983).
The northern water snake is active both day and night but is most active between 21 and 27 degrees C (Brown, 1958; Smith, 1961). During the day, they are found in areas that provide basking sites and are not found in heavily shaded areas (DeGraaf and Rudis, 1983; Lagler and Salyer, 1945).