Snakes hibernate throughout the winter to conserve body energy. Snakes are cold-blooded reptiles whose body temperature depends on external influences. Hibernation in snakes is also referred to as wintering, dormancy or brumation.
Hibernation is any long-term reduction in body temperature, metabolism, heart rate and breathing. Hibernation begins in late autumn and ends in early spring. When good wintering locations are sparse, large groups of male and female snakes den together. Snakes do not survive in the frigid areas north of the Arctic Circle or in Antarctica, and on some islands in Ireland and New Zealand, there are no snakes at all. However, in temperate climates, snakes may choose not to hibernate.
Snakes will enter rock cervices or hide under logs in order to shelter from the cold weather. It is normal for snakes to gather in one particular place in order to conserve more heat. Once the cold season passes, snakes come out of shelter in order to bask in the sun. During cold seasons, snakes hunt less and use up body fat that was stored up during warm seasons.