What is brumation?
Brumation is, in simple terms, the snake equivalent of hibernation. Many temperate species of Colubrids, particularly those from America such as the Western Hognose and of course Corn Snakes carry out this form of hibernation as part of their natural seasonal behaviour. As snakes are cold blooded, they require heat from their environment in order to digest food. In the winter months when temperatures are much lower, they have adapted to survive the season by becoming almost dormant in order to conserve energy, meaning they do not have to eat and therefore do not require high heat to digest food. Interestingly, and unlike true hibernation, brumating snakes are not asleep - they are alert and fully aware of their surroundings, they are simply less active, lowering their heart rate down to as little as 5%, and shut down their digestive system, liver and kidneys almost completely - as a result, they loose very little weight despite not eating for up to 6 months. They continue to move around, albeit with much reduced frequency, and continue to drink water throughout.
Brumation is triggered in late autumn with reduced daylight hours and lower daytime temperatures. This lasts throughout winter, until early/mid spring where daylight hours become longer and temperatures begin to rise again. The end of brumation also marks the start of the annual breeding season.
Captive bred snakes do not experience a seasonal shift in day time temperatures of course, but they can often begin to instinctively prepare themselves for brumation regardless, perhaps triggered by fewer daylight hours, or cooler night time temperatures. It is very common for them to begin rejecting food in autumn, and become very inactive. In these instances it is actually safer and less stressful for them to be allowed to brumate properly, rather than be forced to endure high temperatures - in order to shut down their organs and lower their metabolism, they must be able to lower their temperatures. Without the correct temperatures, snakes that attempt to brumate at high temperatures lose weight due to not eating, so it is safer to allow the snake to brumate properly, rather than attempt to prevent it - brumation is a perfectly natural act which temperate snake experience and have adapted into their natural annual cycle. There are a few benefits to brumation too; it marks a natural start to the breeding season, and properly brumated snakes are linked with higher levels of fertility, improved breeding success, and the increased likelihood of females laying double-clutches of eggs. It is, however, crucial that all snakes are in tip-top health and injury free before being allowed to brumate - respiratory infections can flare up due to the lower temperatures, and injuries cannot heal due to the extremely low metabolisms.
My Method
Once again, this is an area where I found - as a whole - information readily available on the internet to be a little patchy, and very brief. I spent many hours researching things like average regional day and night temperatures by month for a handful of States where Corns are native to, as well as average precipitation / humidity by month, and daylight hours by month. I also looked at natural habitats, and other breeders guides, before coming up with my own variation on the methods. I'll set out here the stages of brumation by month.
October
Temperatures are kept at their normal 31 degrees C hotspot on a 12/12 day/night cycle for the full month. I do not provide my Corn snakes with night time heat, as they experience cool evenings naturally, so throughout this month they will become aware of the gradually lowering night time temperatures, as well as shorter day light hours. Feeding is increased slightly to every 7 days here. I also used this month to set up my brumation tubs:
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| Basic brumation tub |
These are basic plastic tubs with secure lids. Good ventilation is important to maintain a constant low humidity - I add one row of 12 holes low down on one side, and another row on the opposite side high up - this creates good air flow through the tub. The tub is then filled about 4 inches deep with clean Aspen to allow the snakes to burrow, and a hide added too. A large waterbowl is important - brumating snakes continue to drink and fresh water must be available at all times, so a large waterbowl means I have to disturb them less frequently - plus it doubles as an additional hide. And that's it, nothing too fancy required here, but security is key. Each snake has their own tub - they should not be brumated together (even if they co-habit the rest of the time).
November 1st
Temperatures are held for a further two weeks, but feeding stops. It is important to allow snakes to fully clear their systems prior to having their temperatures lowered - brumating snakes on full stomachs can be very dangerous, so temperatures are held for two weeks after feeding has stopped.
November 15th
Now I begin lowering temperatures very gradually, turning the thermostat down 1 degrees every two days over a two week period, so that by December 1st, temperatures are down to the low 20's. I also change the day / night cycle to only 10 hours of heat / 14 hours of room temperatures. I also started leaving thermometers in various locations of the house, looking for one spot of about 18 degrees, and another below 16 degrees.
December 1st
The Corns get placed into their brumation tubs, and placed somewhere that hovers around 17/18 degrees for two weeks (top of the cellar steps for me). They are checked in on most days, and water topped up, but otherwise they are left to settle down for the winter.
December 15th
Each snake is briefly removed from their tub whilst I give them a good check over for any signs of ill health, particularly Respiratory Infections, and clean up any last little excretes. Waterbowls are cleaned and filled up, snakes are returned, and the tubs are moved to an area where temperatures are lower than 16 degrees (cellar) - it is important to keep them at or less than this temperature for their metabolisms to shut down. Other than water changes, I wont see them again now until mid February.
Bringing the snakes out of brumation is done as gradually as it was going in:
February 1st
The tubs are moved back to the top of the cellar steps again for another two weeks, where temperatures are a little warmer, hovering between 16 and 18 degrees C.
February 15th
The snakes are moved from their tubs and back into their freshly cleaned vivariums. No daytime heating is provided here for a further two weeks - they reacclimatise to a natural daylight cycle, at room temperatures.
March 1st
Now the heating goes back on, set at 20 degrees on a 10 hour cycle. Over the course of two weeks, it is gradually increased a little each day, until a basking spot of 31 degrees is once again achieved. I'll then set the timers back to a 12/12 cycle.
March 15th
Now that all the snakes are back up to normal temperatures and increasing in activity, it's time to offer them a feed. This will be the first time their digestive systems have seen any action in over 4 months, so it's important to ease them back into it with a small prey item. Further feeds are offered throughout the remainder of March, gradually increasing in size until back onto a normal schedule.
And that's all there is to it! All snakes are back to their usual routines and look remarkably bright and healthy. They will go through a post-brumation shed after a couple of feeds - this is like clockwork; males shed after two weeks of their first feed, and females begin to shed about two weeks after that. Once all snakes have finished their post brumation shed, it's breeding time.
