Water moccasins, commonly known as cottonmouths, are venomous snakes native to the southeastern United States. These semi-aquatic reptiles are often found near various water sources, including swamps, marshes, ponds, and streams. During colder months, a common question arises: do they truly hibernate?
Understanding Brumation
Water moccasins do not hibernate in the same way mammals do; instead, they undergo a similar process called brumation. Brumation is a state of dormancy cold-blooded animals, such as reptiles and amphibians, enter during cold weather to survive when temperatures drop and food becomes scarce.
During brumation, a water moccasin’s metabolic rate significantly slows down. Unlike hibernating mammals that enter a deep sleep and primarily rely on fat reserves, brumating reptiles may experience periods of wakefulness. They might occasionally emerge from their sheltered spots to drink water, though they generally do not eat. This helps them conserve energy and endure winter’s harsh conditions.
Winter Retreats
As temperatures decline, water moccasins seek sheltered locations for their brumation period. They often choose sites that offer protection from the cold and potential predators. Common winter retreats include burrows abandoned by other animals, such as crayfish, tortoises, or various mammals.
These snakes also utilize natural crevices, hollow logs, or spaces beneath rotting stumps and leaf litter. In some northern parts of their range, water moccasins may even overwinter communally in rock fissures or bluffs. These sites provide insulation against freezing temperatures, aiding their survival.
Seasonal Activity
Water moccasins typically begin their brumation period in late fall, usually around November, and emerge in early spring, often by March. The duration can vary depending on the specific geographic location, with those in warmer southern regions potentially experiencing shorter brumation or omitting it entirely. Environmental cues like decreasing daylight hours and falling temperatures trigger this dormant state.
Once temperatures rise and days lengthen, water moccasins become active again. They emerge from their winter retreats to bask in the sunlight, regulating their body temperature. During warmer months, these snakes are primarily active at night, especially when it is hot, but can also be seen during the day. Their return to activity marks the beginning of hunting, breeding, and other behaviors for the species.