The role of the midland water snake, Nerodia sipedon (Serpentes : Colubridae), as a predator: foraging behavior, kin recognition, and the response of prey
The midland water snake, Nerodia sipedon, is very abundant in portions of the southeastern U.S.A., where it may play an important role as a predator in freshwater communities. I examined whether foraging mode in naive neonatal snakes was phenotypically plastic or canalized and I compared handling times and capture efficiencies for different prey types (juvenile fishes and frogs) between neonatal and adult snakes. I also tested for kin recognition by mother snakes by comparing their consumption of unrelated (non-kin) and related (kin) neonates according to time and the availability of alternative prey (fish). In addition, the response of prey in the presence and in the absence of snakes was tested by comparing the amount of time that juvenile fishes utilized areas containing different microhabitat complexities and by comparing the amount of time that fishes were actively moving. Overall, foraging mode was phenotypically plastic, handling times and capture efficiencies differed by prey type and snake size class, kin recognition was confirmed, and fishes did not alter their habitat selection or activity patterns in the presence of snakes.