If you live in a colder country that has wild snakes, you’ve probably noticed that there are fewer snakes around in the colder months. Snakes seem to vanish before returning when it’s warmer.
Snakes brumate. Brumation is a low-energy state which snakes go into over the winter. It’s similar to hibernation, except snakes don’t go into a deep sleep. They just stop moving around as much to maintain their body temperature and conserve energy.
In this complete guide, we’ll share some interesting snake hibernation facts. You’ll learn what brumation is, why snakes brumate and if it’s common in all snakes. We’ll then look at how long brumation lasts for, where snakes go to brumate, and whether snakes brumate in captivity.
What is Brumation?
Brumation is a low-energy state that some reptiles enter during the colder months of the year. It’s the reptilian equivalent of hibernation, occurring in response to falling temperatures.
In the autumn, before brumation begins, snakes sense that the temperature is starting to drop. In response, they may eat more than usual, to build up their body’s fat stores.
During brumation, snakes don’t eat at all. It’s, therefore, essential that their bodies contain enough fat to keep them going until spring.
When brumation begins, snakes will stop eating. They will seek out a place to rest, ideally near a source of heat. Snakes rely on environmental heat to regulate their body temperatures, as they’re ectothermic (cold-blooded).
During brumation, snakes become very lethargic and do not move very much. They still drink water and will move to get to a water source. However, they don’t eat during this time.
In the spring, when temperatures start to rise, snakes come out of brumation. This is usually the time of year when females seek a mate, to ensure that the babies will be born before the winter arrives.
Snakes aren’t the only type of reptile that brumates. Many tortoises, geckos, bearded dragons and other lizards also brumate.
Brumation vs. Hibernation
You might be under the impression that brumation is the same as hibernation. And in fact, the two processes are quite similar. Both processes are dormancy, triggered by drops in temperature and reduced daylight hours.
In both states, animals build up fat reserves before becoming dormant and use these reserves for energy over the winter. And in both hibernation and brumation, feeding stops throughout, resuming again in the spring.
However, there are some distinct differences in the biological processes.
- Hibernation occurs in endothermic (warm-blooded) animals. It’s defined by a deliberate reduction in body temperature caused by a slowed metabolic rate. Snakes are ectotherms, so they do not lower their body temperature deliberately. Instead, they brumate to prevent their body temperature from falling too low.
- Animals that hibernate sleep throughout the winter. Snakes do not sleep when they brumate; they are less active. If there’s an unusually warm day in the winter, snakes may venture out of their hiding place for a while before returning in the evening.
- Snakes still need to drink water when brumating. When mammals hibernate, they go without both food and water throughout the process.
- During brumation, snakes and other reptiles can tolerate low oxygen levels. Turtles can even brumate underwater and in the mud. Hibernating mammals, of course, can’t.
So, though hibernation and brumation are relatively similar, it’s wrong to say that snakes hibernate. They are biologically different processes. Hibernation only occurs in endothermic animals.
Many pet owners find it hard to tell the difference between a dead and hibernating snake.
Do All Snakes Brumate?
Not all snakes brumate. It all comes down to their environment and the temperature of their natural habitat. In short, snakes which live in countries which are cooler in the winter will brumate.
Tropical snakes, living in areas closer to the equator (such as South America), will not brumate. This is because there isn’t any need for them to do so.
All snakes native to America brumate, because of our relatively cold winters. Snakes frequently gather together in large groups to brumate, to help preserve body heat.
However, snakes native to warm, tropical climates do not brumate. Boa constrictors, for example, are native to Central and South America.
In their native habitats, temperatures do not drop low enough for brumation to be necessary. These snakes can continue functioning as normal throughout the winter with no ill effects.
It’s hard to say whether snakes from tropical climates would brumate if they did encounter colder temperatures. They would undoubtedly move more slowly and be less active, though whether it would be classified as true brumation is less clear.
One thing’s for sure, though: if you have a tropical snake, don’t attempt to test it out. Tropical snakes often experience respiratory infections at colder temperatures, so it’s not worth the risk.
Why Do Snakes Brumate?
Animals regulate their body heat in one of two different ways:
- Endothermic animals, also called “warm-blooded,” generate their own body heat. Most mammals, including humans, are endotherms. Our bodies regulate our temperature via a process called homeostasis. Through this, we’re able to keep our core temperature at around 98.6 degrees Fahrenheit, regardless of whether it’s summer or winter.
- Ectothermic animals, sometimes erroneously referred to as “cold-blooded,” depend upon external sources of heat to warm up their bodies. Most reptiles are ectothermic.
As well as being ectothermic, snakes are poikilothermic. This means that their internal temperature can vary considerably with no ill effects. They can survive and function over a much wider temperature range than humans. However, there are still upper and lower limits to this.
All animals use a process called thermoregulation to keep their body temperature within safe boundaries. But because snakes cannot produce their own metabolic heat, they have to do this by seeking warmer and colder areas as the need arises.
This is where brumation comes in. In the winter, it’s too cold for most snakes to survive out in the open. Moving around and hunting prey uses a lot of energy, and if their body temperature were to drop too much, they’d die.
Brumation helps them to thermoregulate over the colder months. Their extra fat stores mean that they don’t need to feed, saving energy.
At What Temperature Do Snakes Hibernate?
The temperature that will trigger a snake into beginning (and ending) brumation depends slightly upon the species. This is because of evolutionary adaptation. Snakes which are native to colder areas can generally withstand colder weather than those from tropical climes.
That being said, it is possible to provide a general estimate. The “cutoff point” for most species of US-native snake tends to be about 60 degrees Fahrenheit.
When temperatures start to drop below that level, snakes will begin to brumate. In the spring, when temperatures begin to creep back up to 60, snakes will start to come out of brumation.
Of course, this is not set in stone. The environmental temperature triggering snakes to go into brumation will vary slightly by species. The length of daylight will also have some effect, as this helps snakes figure out that winter is approaching.
How Long Do Snakes Hibernate For?
The precise length of time during which snakes brumate varies. It is dependent on both the species of snake and the area in which it lives.
Generally speaking, snakes will brumate from late autumn until early spring, when the temperatures rise. However, this will vary depending on the climate in the region where the snake lives.
Let’s take the United States as an example. In the northern states, such as Minnesota, temperatures drop earlier in the year than they do in the southern states, such as Florida.
It also takes longer for temperatures to rise again in the spring. So, in these states, snakes will brumate for longer periods of time.
As a general rule, snakes will start to go into brumation from late September to early December. This will vary depending on the temperature. In the springtime, snakes generally emerge from their hibernaculum between March and April.
Bear in mind that, unlike hibernation, brumation is not a continuous process. Since snakes do not sleep throughout the process, they may still come out on warmer days. Freak cold snaps can trick snakes into brumating early, but they will surface again when temperatures return to normal.
Where Do Snakes Brumate?
As we’ve already established, snakes brumate to conserve body heat. If they stay out in the open, their temperature may drop to dangerous levels. So, for that reason, snakes look for small, enclosed spaces in which to brumate.
When you’re walking around outside, you won’t see a snake brumating. They’ll never brumate just lying around on the surface of the ground. Instead, a snake may choose spots such as:
- Cracks in rocky outcrops
- Burrows dug by rodents and other animals
- Holes in tree stumps
- Wells and other man-made holes in the ground
Generally speaking, snakes tend to brumate underground. Interestingly, this is the only time of year during which snakes get together, except for mating season. Though snakes are usually quite asocial creatures, brumating together is a great way to thermoregulate.
In other words, they help to keep each other warm. According to a study in the Journal of Herpetology, snakes tend to return to the same hibernaculums (brumation spots) year after year.
You may be wondering: do snakes hibernate in houses? Potentially, yes. Crawl spaces, in particular, are favorite brumating spots for snakes. If there is some way for a snake to get into your home, you may even discover one brumating in your basement.
It’s important, if you find a snake in your home, to avoid the temptation to touch or interfere with the snake. Even if you suspect that it’s a venomous copperhead or rattlesnake, do not attempt to kill it or scare it away. Instead, call a pest control service. In the meantime, leave the snake well alone.
Do Pet Snakes Brumate in Captivity?
Now that you know exactly how and why snakes brumate, you may be wondering: will my pet snake go into brumation? The answer is no, probably not, unless one of two things happens:
- You fail to maintain a warm temperature in your snake’s enclosure during the winter
- You deliberately lower the temperature, to encourage your snake to brumate.
As a snake owner, you need to ensure that their enclosure remains at an ideal temperature for your snake. This will allow your snake to thrive and stay active throughout the year.
In an adequately heated vivarium, which remains warm year-round, snakes in captivity will not brumate. This is because they won’t need to. The only reason snakes go into brumation is because the temperature is low enough that it demands it.
Be sure to always keep a close eye on the temperature inside your snake’s vivarium. Use a thermometer (or even better, a heating system with a thermostat) to maintain a consistent temperature year round. This will prevent your snake from going into brumation. The ideal temperature for your snake will vary according to its species.
Brumating Your Snake for Breeding
Some snake owners who wish to breed their snakes will deliberately lower the vivarium’s temperature to encourage brumation.
This is because the springtime, when snakes come out of brumation, is prime breeding time. Often, the process of coming out of brumation will trigger snakes to seek a mate.
If you’re planning to breed your snake, brumating is not essential. Snakes will often mate even without going into brumation first. If you do wish to try brumating your snake, do not attempt it without doing your research first.
Not all species of snake can brumate. Even for those who can, lowering the temperature too much, for too long, or not ensuring that your snake has emptied itself of all waste first can have devastating effects.
According to the Journal of Animal Physiology and Animal Nutrition, going into brumation with waste in the digestive system can cause intestinal impaction, which can be fatal.