Many people are concerned about the below-freezing temperatures. Tortoises that are in well-insulated burrows will be fine. The burrows will do their insulation job. To cut down on air circulation, you may wish to ball up some paper and put it in the burrow opening while the temperatures are so cold. (Don’t seal the burrow.) Remove the paper by February. If your tortoise does not have much protection, put him in a cardboard box using the following guidelines.