So people ask me, and I see a lot of ‘talk’ on the forums about the exact nature and techniques that are required to properly cool an animal down for the winter. A lot of questions are asked and the most common are the obvious such as: “At what temperatures should I cool my geckos? And for how long”, “Should I feed them during this time?”, “Do juveniles or first year breeders need to be cooled?” or “Is it really necessary for me to cool my reptiles?”. I read or hear questions like this very often, and naturally this is a sensitive topic as this time of year can be very stressful and testing of the hobbyist. A lot of uncertainty and blind trust must go into this process unless one has years of experience with brumation. Oh yeah, and brumation is the art of hibernating one’s reptiles if you did not know that term. What I will attempt to cover here is a detailed account of my personal knowledge and experience with brumating my geckos and hopefully I can offer some guidelines and answers to some of the questions you may have in regards to it.
Now that winter is upon us, you will need to give them a period of rest in order to have your animals ready for the upcoming spring and summer breeding season. This is the bottom line behind the winter cooling which is also known as brumation. Essentially all reptiles in the wild experience a natural reduction in ambient temperatures during the winter, and this time is what we as keepers would like to replicate with our reptiles in our homes. I ask a lot of questions of people in the hobby and like to learn from their experiences and through this effort I have heard different accounts regarding different species about whether or not cooling is a necessity for successful reproduction. Some say it is not necessary to brumate and that they personally do not choose to cool their animals. Others have said that they cool their animals every winter and that the outcome is greater success in breeding and reproduction.
Which Animals to Brumate
So where does that leave us? I believe it leaves us with the question of purpose and exactly what we want to get out of our animals. Brumation can be very risky as it is common for reptiles to die at this time. I would not recommend brumation to anyone that owns animals for fun and is not looking to breed the geckos, or for those animals that are not completely 100% plump and healthy. I have found that animals that get put into brumation that are not very healthy generally do not live through this testing time and therefore it is not recommended. In nature these ‘weak’ individuals would not make it and the theory of only the strong survive would prevail and possible weaker genetics would be eliminated from the species gene pool. But in captivity we have the opportunity to avoid these harsh realities of nature by accommodating our animals with ideal environments. Much of the risk associated with brumation is due to lack of know-how and the attempt to cool a gecko incorrectly or to cool a gecko that is not in optimal condition.
I would never recommend brumating a juvenile gecko or a first season potential breeder as this could be beneficial time that the juvenile could be using to eat, grow, and mature. Brumation is usually not necessary for first year breeders either, except in the case of some rare and hard to breed species that come from extreme climates, but I am not dealing with them here as I am just trying to provide a solid basis for cooling one’s reptiles. Brumation really is a topic that a whole book could be written about, and it comes down to what an individual species goes through in its natural environment climate-wise, such as winter time temperature lows, average rainfall, humidity levels, etc. Knowledge of the environment and climate of an animal’s ecosystem is the basis of this hobby and should be referred to during brumation for the individual species that you would like to cool.
Temperature and Brumation
A problem that can occur in brumation is when the reptile is not cooled at low enough temperatures to stop its metabolism. This results in weight loss and can sometimes be very drastic and happen quickly. I believe this is a simple problem of being informationally unprepared, that’s all. Exact temperatures are species dependant and this is why one needs to contact others that have cooled the particular species and have had success in doing so, and/or to study the local climate of the species. For my Australian knob tail geckos I will bring the entire genus down to about 60F where I let them idle for two months. And that’s the thing right there, there is no one set temperature that all animals can be taken down to, and that is precisely what I meant when I mentioned “species dependent” a few sentences ago. There are just too many species that have evolved in totally different climates to oversimplify this. I wouldn’t cool my tropical animals such as Phelsuma for instance at 60F as it would most likely kill them since they would never experience a temperature that low in their native environment. I would rather slow down on feeding so much and just let the ambient room temperatures drop as these geckos will notice a 5-10 degree drop much moreso than those that can tolerate colder weather. So in summary, the part of the world the animals are from (closer or farther from the equator) correlates with whether they experience more or less of a temperature change between their summer and the winter.
Preparing for Brumation
To prepare my geckos for brumation I make sure they are fully grown, fed heavily and that adequate fat reserves exist on the individual, whether in its tail, neck, or behind its front legs. This can also be easily determined by measuring the gecko’s length, as well as by weighing the animal, and lastly by determining its age. Then when I feel the individual in question is at its peak health I stop feeding him or her altogether. I continue to offer water whether in a bowl or by regular mistings. I leave the animal at its normal climate for 5 days or so and then I start slowly lowering the temperatures over the next two weeks until I reach the desired cooling temperature. The goal here is to have the animal excrete anything that is in its digestive system as it cannot remain in its gut during brumation or problems may arise. I achieve this by lowering my thermostat temperature on my rack a degree or two a day, or by using a rheostat for a heat pad or heat bulb, etc. You can be creative here as this is no exact science. I monitor temperatures daily with a temp gun to ensure that the temperatures are slowly lowering and that I am getting to my desired temperature low.
The Brumation Period
By day 19 without food I have reached my steady brumation temperature where I will keep my reptile for a set amount of time. Again, I just offer water during the brumation period and no food! The idea here is that your reptile’s metabolism will slow down to a near standstill as heat is the main factor needed for metabolizing food in reptiles. Therefore your reptiles should not lose any or very minimal weight during brumation.
Now the question of how long the brumation period should be arises. This is also species specific, but generally I will keep them at this temperature for 30-90 days. Some species that live in colder climates with longer winters do require brumation in excess of 3 months. The length of the winter in the species native habitat will determine what time period is right for your gecko species. The difference in average highs and lows in temperature between the seasons also plays a big part.
Ending the Brumation Period
To bring my geckos out of brumation I do the opposite from what I did to get them down to their cooling temperatures. Over the course of two weeks I slowly warm them up until they are back at their ideal summer (hot) temperatures. I offer them food every other day after a week of slowly raising their temperatures and they usually will eat very eagerly before they are back at their high temperatures, but others will need a bit more time for their metabolisms to speed up; generally all geckos will eventually eat after a few days at the latest of being at their normal temperatures. Once they are eating they are usually “in the clear” of any adverse reactions to the cooling.
I feel it is essential to learn and study the yearly climates that your species face in the wild and implement them in your brumation plan. There is no easy one step answer for how to brumate. Speak with those from whom you acquired your animals and get to know how they did it and what methods worked for them. Knowledge is key here. You can never have too much of it.
I have found that healthy geckos come out of brumation looking just as good as when they went in. If an animal is losing weight during the cooling it is best to try and save it by slowly warming up the temperatures until it is at its normal heat levels and get the animal to eat again so that it can put on some of that lost weight. Sometimes individual geckos or certain species of gecko need a year off from brumation or breeding. An animal will either lose weight during brumation because it is not ready or healthy enough, or because the temperatures are not cool enough which would make it metabolize its fat reserves. When I have my geckos brumating I try to keep them in a dark, quiet area, and I try not to bother them unnecessarily. I leave them alone except to lightly spray the walls for them to drink, or to fill up their water container every 3 days on average.
So real quick to wrap this up: one can brumate in many different places including but of course not limited to a basement, attic, closet, garage, and even in a wine cooler or any temperature regulated refrigerated unit. And if you find that you have an ideal area but it is a bit too cold, you can always get a thermostat and set a heating device to the temperature that you require and this will make the best of what you have to work with. I hope that this article will help some of you readers in the future! Good luck! I can always be contacted and my information is located on my blog.