Hibernation - A Special Sleep

Animals in true hibernation can be moved around or be touched without any response. This state is frequently described as sleep but it is far different than regular sleep. In normal sleep, an animal can wake up quickly. With hibernation, the animal appears dead. To wake it takes a very long time; and once aroused, it can’t return. To prepare for hibernation, an animal will eat more than usual in the fall. Instead of putting on normal fat, a special fat is produced which will use as fuel during hibernation. As their body is preparing for hibernation, the animal will get sluggish. Scientists believe body weight determines when it will bed down. Once it enters hibernation, its body temperature drops very low so that it almost matches the outside temperature. Its heart rate and breathing will slow tremendously. All of this conserves energy. It will no longer defecate or urinate as its body will reprocess the liquids. Nor will it lose muscle strength. The whole process is similar to a controlled state of hypothermia but without damage to cells, organs or brain. It is believed an internal clock and possibly hitting a critical level of fat reserves causes the animal to wake up in the spring. In CT only the woodchuck (aka groundhog) & the brown bat hibernate. Some scientists now call this process “complete torpor” and the time period the animal is “asleep” hibernation. Regardless, it is nature’s adaptation to prolonged cold and lack of food. (Photo - Hibernating bats www.arkive.org)