Cooling Down to Heat Things Up: How to Brumate Snakes for Winter Breeding

1. Introduction

Brumation is the reptile equivalent of hibernation, but it works a little differently. Unlike mammals that sleep through the entire winter, snakes enter a dormant, slowed-down state where only essential bodily functions remain active. They’re not fully asleep, but they become lethargic, inactive, and uninterested in food.

For breeders, brumation isn’t just a natural cycle—it’s often an essential part of preparing snakes for a successful breeding season. Some species absolutely require it to cycle properly, while others may not tolerate it well at all. The needs vary depending on the species and their native habitat. For example, a California Kingsnake may only need temperatures in the low to mid 60s, whereas a Bamboo Ratsnake may need to go down into the low 40s.

Each species not only has different temperature requirements, but also different ideal brumation lengths. Based on experience, I’ve seen better consistency, higher fertility, and stronger breeding responses in brumated snakes compared to those that were kept warm year-round. Even younger snakes that aren’t sexually mature—once they’re a year or two old—can benefit from going through a seasonal cycle. It helps set them up for future success.

Brumation can also help reset a snake’s appetite. If you have a finicky feeder that tends to get spotty during the colder months, a short brumation period can trigger a false “spring,” getting them to start eating consistently again once they come out of it.

2. Why Brumate? (Breeding Perspective)

The benefits of brumation—especially for breeders—are hard to overstate. For species that naturally experience a winter slowdown in the wild, brumation serves not just as a seasonal cue, but as a physiological reset. In my experience, snakes that don’t go through this process year after year seem to have shorter lifespans, poorer breeding consistency, and weaker fertility.

From a health standpoint, brumation allows the digestive system and internal organs to rest. But from a breeding perspective, skipping brumation can completely throw off your rhythm. Females often cycle erratically—or not at all—and in collections where you’re trying to time multiple pairings, this creates a chaotic window of opportunity. This is especially true for species like colubrids, where you can’t always see visible signs of ovulation or follicle development. You may pair a male who’s ready with a female who isn’t—or vice versa—and end up wasting valuable time and opportunity.

Fertility also takes a hit. I’ve seen poor sperm quality in males that were kept warm year-round, and smaller, inconsistent clutches from females that didn’t go through brumation. In some cases, a species that should be producing a dozen eggs ends up laying just one or two—if any.

Brumation also provides a clear seasonal reset, both for you and your animals. Once the snake emerges from brumation, it knows it’s go-time—and so do you. That predictable window makes planning your breeding season much more structured and consistent.

Most importantly, both males and females need to be cooled. A warmed-up male with poor-quality sperm won’t produce viable offspring, and a female that didn’t cycle correctly may produce slugs or no eggs at all. Proper brumation ensures both partners are hormonally aligned and physiologically primed.

3. Preparing for Brumation

Proper preparation is everything when it comes to safe and successful brumation. A snake that enters this dormant state with food still in its digestive tract is at serious risk—a meal left inside a brumating snake can rot and cause death. To prevent this, I stop feeding a full month before I begin the cooling process.

The first two weeks of that month, I keep their enclosure exactly as it would be during their active season—full heat, normal lighting, no changes. This gives the snake time to fully digest and pass any remaining waste. During this period, most snakes will defecate one or more times, fully clearing their systems.

Then, in the second half of the month, I turn off the heat and let the room cool to ambient temperature—around 75°F in my case. This temperature is still safe for digestion, especially for colubrids, but begins easing the snake toward dormancy. This slow reduction in warmth acts as a natural prelude to winter conditions.

Before cooling, I also evaluate each snake’s body condition. A skinny or unhealthy snake should not be put into brumation. Even at low temps, they’ll lose weight, and without sufficient fat reserves, that loss can be dangerous. Brumation is taxing—snakes need to be well-fed and in good health to handle it.

That’s why I focus heavily on feeding them up during the summer and early fall. Some snakes will naturally start refusing food in late fall as they sense seasonal changes coming, so it’s important to get weight on them well before that window closes.

For the cooling process itself, I individually tub each snake and place them in a temperature-controlled wine cooler. I start at 65°F, gradually bring it down to 50°F, then bring it back up to 65°F again over the course of about three months. This mimics a natural seasonal cycle without shocking the animal’s system.

Bottom line: give them a full month off food, confirm they’ve passed all waste, and make sure they’re healthy and well-fed before cooling them down.

4. Setting Up a Brumation Environment

When setting up your snakes for brumation, simplicity, consistency, and reliability matter most. I use containers that are just large enough for the snake to coil comfortably. They don’t need space to roam—they’re going into a low-activity state, so oversized tubs are unnecessary.

Each tub includes a small water bowl, which I glue down so it doesn’t tip or move around. Water is critical—even during brumation, snakes will drink occasionally, and dehydration is a serious risk, especially in drier environments like wine coolers.

For the cooling system itself, I highly recommend using a high-quality wine cooler. It doesn’t have to be expensive, but it should be reliable and preferably new. I know breeders who used older or secondhand units and ended up with tragic results—some coolers dropped too low and actually froze their snakes.

Most wine coolers have built-in thermostats, which I verify with external thermometers. I start at 65°F, gradually drop down to 50°F, and after about three months, bring it slowly back up to 65°F. This temperature curve mimics a natural winter cycle.

For substrate, I stick with aspen, which is clean, low-moisture, and easy to monitor. Each tub is well-ventilated to prevent humidity buildup. Moist, stagnant air can lead to respiratory issues or mold—especially in enclosed cooling units.

Once a week, I open the wine cooler and check each tub. I look for spilled water, shavings in the bowl, or signs of dehydration. Even in brumation, snakes will shift position occasionally. Keeping their water clean is important—they’re vulnerable during this time, and drinking dirty water could lead to problems when their immune system is at its lowest.

5. Monitoring During Brumation

When snakes are in brumation, less is more. The goal is to let their bodies follow a natural cycle without unnecessary interference. That means no weekly handling, no weighing, and absolutely no pulling them out of their tubs to “check in.”

Lighting is another important factor. In the wild, most snakes would be brumating underground in total darkness. If your wine cooler is in a lit room, cover it with a blanket or towel to block out ambient light.

That said, light monitoring is still necessary. About once a week, I open the cooler, quickly check each tub, and make sure water bowls are clean and not spilled. I don’t open the tubs or handle the snakes—just a quick visual through the clear tub sides or lids.

You may see a tongue flick or slight repositioning, and that’s fine. Most snakes remain still, but some—like Arizona Mountain Kingsnakes—may move more during brumation. Occasional activity isn’t a concern unless it’s paired with signs of illness.

The biggest red flag is cold + wet. A spilled water bowl in cold temps can quickly lead to respiratory infections. Gluing bowls down and using dry substrate like aspen helps prevent this.

If you keep things cold, dry, dark, and consistent, your snakes will brumate safely.

6. Ending Brumation & Waking Them Up

After gradually ramping the temperature back up to 65°F in the wine cooler, I begin waking the snakes by moving them to room temperature, still in their brumation tubs. My room stays around 75°F, which is ideal for easing them back into activity.

I keep them at room temp for a full week without heat or food. This slow adjustment allows their systems to fully restart. After a week, I place them back on heat and offer their first meal.

Some snakes will eat right away. Others may need a little more time. Most will eat reliably by the second week on heat.

During this post-brumation period, I feed every 2–3 days. This feeding frequency is part of the cycle—just like cooling down triggers dormancy, frequent food intake helps trigger breeding. You’re recreating spring, both with temperature and abundance of prey. Together, this strongly signals the body that it’s time to reproduce.

7. Post-Brumation Feeding and Pairing

I like to start pairing after about 4–5 meals. That early post-brumation feeding window is critical. Pairing too early—before the female has rebuilt weight and energy—can lead to poor fertility or dud eggs. Letting her get in a few meals ensures she’s primed and ready to cycle correctly.

If a female comes out of brumation underweight, that’s not the end of the road. With consistent feeding every 2–3 days, you can get her back into condition within a few weeks. Once she’s visibly putting weight back on, she’s ready to pair.

Males often show they’re ready by going off food shortly after warming up. They’ll start tongue-flicking more, pacing their tubs, and generally showing more active interest in their surroundings. When you see that shift, it usually means they’re hormonally ready to breed.

When both animals are properly warmed, well-fed, and behaviorally responsive, it’s time to pair.

8. Final Tips and Common Mistakes

Brumation seems simple, but there are plenty of ways to mess it up—some I’ve learned the hard way. Early on, I made the mistake of not cooling my snakes enough, afraid I’d go too cold. But many species do better at lower temps than people think—mid-50s to even low-40s are completely normal for some species.

Another mistake I’ve made was not providing water during brumation. While no snakes died from dehydration, they came out looking flat—less muscle tone, slower to recover. Now I always provide water and check it weekly.

But the key is balance:
Cold and dry = good. Cold and wet = trouble.

If water spills and creates a moist environment, you’re risking respiratory infections and other issues. That’s why gluing down the bowl and using dry substrate is non-negotiable for me.

I also can’t stress enough the value of a good quality wine cooler. Some people try to brumate snakes on a garage floor or in a cold room, and while it might work in the right climate, it’s risky. Just a few days of unintended warmth can throw a snake’s cycle completely off—or worse, cause it to burn through fat reserves without eating.

If I could give one golden rule:
Keep it cold, keep it dry, and be consistent.
Do that, and your snakes will come out strong, cycle properly, and breed reliably.