How The Babies Are Made
The Northern Banded Water Snake has a very interesting method of reproduction. First of all, the snakes are dioecious, which means seperate sexes. The male snakes are ready to reproduce by the time they are 21 months old, whereas the females cannot reproduce until they are at least 3 years old! Most of the reproduction happens between the middle of April and the middle of June, and it usually happens near the snakes' hibernation site. The snakes only mate once each year, and produce litters of between 4 and 99 offspring. Unlike most snakes, Nerodia sipedon does not lay eggs, they give birth to live offspring after a 3-5 month gestation period.
Photo by Andrew Durso
The mating process begins when the male snake maneuvers itself along the side of a female, and rests his chin on the female's back. While this initial process is going on, it is common for the male snake to give several spasmodic jerks. After this phase is complete, the snakes twist their tails together in order to attach the cloacal openings, and begin producing their offspring. After mating has occured, the female Nerodia sipedon nurtures and protects the young until birth. When born the snakes are completely independent and able to care for themselves.