Ar-Rehman

Snakes disappear with drop in temperatures

Snakes play a vital role in your garden’s ecosystem by controlling pests, even if they disappear in winter. As temperatures drop, snakes enter brumation, a slowed-down state where they stop eating and conserve energy. To stay safe from freezing temperatures, garter snakes retreat below the frost line into protected spaces like abandoned rodent, crayfish, or groundhog burrows, rock crevices, stone walls, and tree stumps, piles of firewood, compost heaps, spaces beneath sheds or decks, and sometimes basements. Like other cold-blooded animals, snakes rely on external temperatures to regulate their body temperature. As the weather cools, their metabolism slows and they retreat to sheltered spots where they can ride out the winter. We have discussed here, to find out where snakes go in winter, how their behavior varies by region and species, and what their seasonal disappearance means for your garden.

Garden snakes have important roles in your landscape, eating insects and invertebrates such as slugs and providing food for birds of prey such as hawks and owls. You may see them occasionally during warm weather, though they seem to disappear entirely from your garden when cool temperatures arrive. Of course, garden snakes still are present in your landscape, though it’s unlikely you’ll spot them in the middle of winter if temperatures remain cold. Snakes are ectotherms, which means they can’t generate their own body heat and must rely on the environment to regulate their bodily functions. As temperatures begin to go below 60 degrees F, they seek somewhere warm to spend the winter. Come fall, temperatures drop and their heart rate, breathing, and metabolism slow down to help them conserve energy. In this process, called brumation, they stop eating entirely because their bodies are unable to digest food, instead relying on fat stores gathered during the fall. They aren’t fully asleep, but much slower and less active. Brumation is sometimes compared to hibernation, but the two processes aren’t identical.

They enter brumation, a reptile version of hibernation, where their heart rate, breathing, and metabolism slow way down. Unlike some snakes that stay alone, garter snakes gather in large groups (sometimes hundreds or even thousands) inside a single den to share body heat and stay warm. On unseasonably warm winter days, they may occasionally crawl out to the surface to bask in the sun or get a drink of water. "On unseasonably warm winter days, it is completely normal for a snake to briefly emerge from its shelter to bask in the sun or drink water before returning underground,” says Michael Starkey, who oversees the snake conservation nonprofit Save the Snakes. The length and severity of this inactive period depend on climate. “Reptiles brumate in areas of the US that receive a lot of snow or have low temperatures for a large portion of the year, with activity picking up along with the warmer temperatures,” says Sake van Wyk of the African Snakebite Institute. “In other regions, like in the southern parts, the temperatures stay high, and these reptiles do not go into brumation.”

Low temperatures slow their metabolism. “They get so cold they almost can’t move,” says John C. Maerz, PhD, Dennis and Sara Carey Distinguished Professor of Forest and Natural Resources, Warnell School of Forestry and Natural Resources at the University of Georgia. “That’s why they must find a moist, sheltered place to spend winter.” While many species of snakes can be found in our yards, what most of us refer to as “garden snakes” are small snakes that remain small, says Maerz. A few of the most common types found in and around your garden in the Southeast are as follows:-

Garter snake is pencil-sized to 1 to 1 ½-feet long, brown to yellow gold with a either a checkerboard pattern or black and yellow striping

Dekay’s brown snake is grayish-brown and about 5 to 10 inches long with a pair of spots or square in rows down its back and a dark head

Red-bellied snake reaches about 5 to 10 inches long and is grayish-brown with an orange-ish red belly.

To survive freezing temperatures, snakes seek out sheltered places called hibernacula, or brumation sites, where temperatures are more stable and they can be protected from the elements. In a garden, that can mean places you might not immediately associate with snakes. “In a garden, snakes may take refuge in manmade structures that provide warmth, such as a shed or barn, or they may hide in piles of debris such as wood or tin,” says Brooke DeMoor, a Wildlife Ecology and Conservation student from the University of Florida with experience in Herpetology. “Rodents also will take shelter in these locations, although most snakes will not eat during brumation.” Some snakes, including garter snakes and copperheads, may gather in communal hibernacula, where grouping together can help them conserve heat. Although the temperature at which garden snakes begin to seek shelter varies by species, all snakes look for places such old animal burrows, compost piles, root holes in the soil, or under decks, rock walls, log piles, or decaying logs to spend the winter. Because it’s rare that soils freeze in the Southeast, they’re usually in relatively shallow spots underground. While some species hang out solo, others, such as garter snakes, may gather in a communal area, called a hibernaculum. Here, they’ll stay together until spring.

It's also not uncommon to find garden snakes in wall voids, under slabs, or in a crawl space or basement. For example, they may accidentally end up in the basement if they curled up in a window well and found a hole to enter your home. If you discover a snake indoors, simply relocate it outdoors. Wear gloves if you like, and once outside, don’t set something, like a log, on top of it for shelter; you could inadvertently squish it. Instead, gently place it in an area such near a wood pile or mulch bed where it can find its own spot to hide. Climate, latitude, weather patterns and species all influence how long a snake remains inactive and where it shelters. In colder northern climates, snakes may retreat underground as early as October and remain in brumation through early spring. In milder southern and coastal regions, winter can look very different. In South Florida, for example, winter temperatures are often mild enough that some snake species remain active throughout the season, particularly during warmer periods. Species matter, too. Nonvenomous species like gopher snakes and garter snakes tend to adapt quickly to suburban gardens, whereas larger pit vipers like rattlesnakes generally seek out deep natural rock crevices or unoccupied burrows well away from high-foot-traffic areas.

Garden snakes don’t build up fat reserves to hibernate, like a groundhog or bear, to survive the winter. Instead, they adapt to the temperatures, staying safely put in their hiding places until spring. Interestingly, garter snakes have a sort of ‘anti-freeze’ with which they flood their cells with sugar to lower their freezing point, so they technically can be a little active at just below freezing temperatures. That’s why you’ll find garter snakes even in the Arctic Circle. Occasionally, you may see garden snakes out sunning themselves on nice winter days if there’s been a stretch of warm-ish days. But they’re not out hunting and will head back to their hiding places in the evening. In warmer climates, however, such as along the coast, you likely will see snake activity in the winter. There’s no universal date when snakes emerge from winter shelter. In colder climates, that may happen in early spring, while snakes in warmer regions can become active whenever temperatures are favorable.

Snakes are predators and thus act as essential, natural pest control in a healthy garden ecosystem. When snakes go dormant in the winter, rodent populations (like mice, voles, and gophers) and destructive garden insects can experience a surge in activity, using winter gardens to look for food and nesting sites. This doesn’t necessarily mean your garden will be overrun with pests. Weather, food availability, habitat, and the presence of other predators all affect local populations. But the return of snakes in spring can restore some of the natural predation which slows during the winter. As temperatures warm up, snakes emerge hungry and immediately go to work managing pest populations, serving as a farmer’s or gardener’s best friend. If you happen to disturb a garden snake in winter, such as when retrieving wood for the fireplace or doing yard cleanup, just leave them be. They’ll know what they need to do to get cozy and find shelter again.