Hibernation in tegus.

Tegus hibernate up to seven months in the wild. They will also do this in captivity if given the chance. However, tegus do not need to hibernate. If they do not hibernate, they may still slow down on feeding, and activity during the normal hibernating season. Note the Argentine species, and the Blue tegus are the only ones to do this that I know of. The Colombians are not known to hibernate.

I will also say that it is not about temperatures. Tegus do not start hibernating because of weather conditions. It is more based on lighting and their internal clock. My tegus start hibernating long before the weather even starts to turn cool. Is still summer weather here in August when mine start going underground.

In the wild, burrows are usually around two feet deep and up to four feet long. Tegus will line these burrows with grasses and leaves. They will also plug the entrance with this as well. It is strongly recommended, by some that Argentine tegus hibernate if the are intended to breed. Bert Langerwerf claims that if these tegus miss a hibernation, they will be infertile and unable to produce viable young. I would tend to agree with this theory. However I have heard both sides on this and there are other thoughts as well.

If a baby tegu misses the first year of hibernation, they can reach three feet in one year. If the baby hibernates he will be the same size at the time as when he started hibernate. Babies that hibernate will reach about half as much or less in size as those that do not hibernate. In my opinion a baby that does not hibernate could have stretched reproductive organs, thus not being able to reproduce. This is not based on fact, but more on a theory. I cannot base this on facts because mine all have and do hibernate each year.

Females that reach two years old start producing eggs in their system before hibernation begins for their third season. These eggs are carried in her system into hibernation. When she emerges, the male copulates and fertilizes the eggs, she lays her clutch and then starts to grow eggs in her body for the following year. If a female misses a hibernation or this cycle, it is believed by some that she will absorb these eggs. It is a big question if she will ever reproduce again. My breeders have never missed a hibernation period, so I cannot say that they would, or would not produce again. Bert claims that they are useless for breeding if they miss one of these cycles of hibernation. I will say this, there are some that have bred tegus that have not gone into full hibernation these have produced eggs. Rick has bred animals that did not hibernate and did produced a good amount of babies.

Colombian tegus are not bred in the United States to any great extent that I know of. They are often times imported. They also do not require hibernation. I would tend to believe they would be more like the Ameivas and whiptails then the Argentine Reds, Argentine Black and Whites, or the Blue tegus.

There are a lot of people asking for some information on hibernating tegus. So, I will try to cover all of this here. I have found that tegus just about do everything themselves. When the time comes for them to start hibernating they will stop eating. They will go a few weeks before they go into full hibernation. Around two to three weeks of coming out less and basking very little.

If kept outside they will refuse to eat at all during this period. They will start spending less and less time above ground. The same thing happens inside as well. Tegus will start refusing food and spend less time out of their hides. When they start this process I stop feeding them all together.
This is also the time I start reducing the lighting times. I keep my lights on my tegus for 12 hours a day in spring and summer, the lights are on 12 hours and off 12 hours. When the tegus start to slow down on feeding and start spending more time in their hides. I reduce the lighting to 10 hours a day, I also stop feeding them all together. I do this for about a week to two weeks. Then I start turning them on for 8 hours for a week. At this point most tegus are usually in their hides for the duration of hibernation. I usually leave the lights on for 6 hours after this point for a week or so. If the tegus do not come out at all, then the lights are turned off for the rest of the winter. If you do see your tegu come out in winter, as this does sometimes happen. Then you can turn the lights on, however these periods usually do not last long. Some might come out for a hour or two and then go right back to hibernating. Most often times they will not come out at all. When and if this happens it is fine to turn the lights back on. But turn them off when they return to their hide. Also, do not feed them. They will not require any food if this happens. I do keep fresh water in the enclosures for about the first six weeks. However I have not seen them drink water either during this time.