Brumation Versus Hibernation
The winter dormancy observed in snakes and other reptiles is scientifically termed brumation, which differs significantly from the true hibernation practiced by mammals. Snakes are ectotherms, meaning their body temperature and metabolic rate are entirely dependent on the temperature of their surrounding environment. During brumation, the snake’s metabolism slows dramatically, but they remain semi-aware and require less deep sleep compared to a true hibernator.
Unlike hibernating mammals, a brumating snake may occasionally wake up and even move around on an unusually warm winter day to seek water. The primary purpose of brumation is to conserve energy until external temperatures rise to a level where the snake can digest food and move effectively. This reliance on external heat means they must locate a specific type of sheltered site, known as a hibernaculum, to successfully survive the prolonged cold. The temperature of this chosen site must remain above freezing, ideally between 35 and 45 degrees Fahrenheit, for the snake to survive the season.
Why Snakes Seek Human Structures for Winter
The fundamental reason a snake is attracted to a human structure is the consistent, moderate temperature it offers compared to the surrounding earth. Natural hibernacula often consist of deep rock crevices, mammal burrows, or dense root systems that provide insulation against freezing temperatures and rapid temperature fluctuations. A house foundation, basement, or crawl space mimics these conditions perfectly by buffering the cold.
Concrete slabs and foundation walls retain heat and shield the reptile from wind and rain. This thermal stability is important, as even a drop below 32 degrees Fahrenheit can be fatal to most species. Furthermore, these protected areas offer security from predators that might otherwise disturb them during their dormant state.
Identifying Common Entryways and Den Locations
Snakes utilize very small gaps to access sheltered areas. The most common access points are small foundation cracks, gaps around utility pipe entrances, and poorly sealed ventilation openings. Any opening larger than a quarter-inch is generally sufficient for a small snake, while larger specimens can fit through gaps the size of a thumb.
Mortar joints in brickwork that have deteriorated or weep holes in exterior walls also provide direct access to the voids inside the walls. Once inside the exterior shell of the building, snakes seek out the deepest, most thermally stable areas. They frequently settle in unfinished basements, dark crawl spaces, or beneath concrete porches and decks that sit directly on the ground.
Inside the home, they may utilize wall voids, spaces behind insulation, or cluttered storage areas in garages that are near the foundation. These locations are appealing because they offer a dark, undisturbed environment with temperatures that remain above freezing. The presence of a snake inside the living area is usually accidental, indicating they have taken a wrong turn while seeking a deeper, darker den location.
Prevention and Safe Handling
Preventing snakes from using a home as a brumation site relies on exclusion, which involves sealing all potential entry points around the building perimeter. Homeowners should use concrete repair compounds to seal foundation cracks and ensure that all window wells and exterior vents are covered with hardware cloth mesh, rather than plastic screening. Particular attention should be paid to the areas where plumbing, electrical conduits, and gas lines enter the structure, as these often leave small, unsealed voids.
Clearing clutter and debris immediately surrounding the foundation is also an effective preventative measure, as piles of wood, rocks, or yard waste can serve as an initial staging area. Addressing secondary attractions, such as controlling rodent populations, will also reduce the incentive for predatory snake species to linger near the structure. A house with a reduced food source and no accessible shelter is significantly less appealing to a passing reptile.
If a snake is encountered inside a house, remain calm, keep a safe distance, and avoid attempting to handle the animal. Homeowners should try to confine the snake to a small area by closing doors and then contact a professional wildlife removal service or animal control for safe identification and relocation. Never try to capture or kill the snake, as even non-venomous species may bite defensively, and handling venomous species poses a serious risk.