HIBERNATION: ANIMALS GO WITHOUT FOOD OR WATER FOR MONTHS AT A TIME

Discover why animals go without food or water for months at a time?

Winter in the wild can be extreme, low temperatures and a scarce amount of food make it difficult 

for many animals to survive. Some will migrate south during the winter months, but certain species of mammals, rodents and reptiles simply bed down and hibernate until spring. Hibernation is an extremely effective survival strategy that suspends the animal’s body functions and metabolism so it can preserve energy. This state of suspended animation will allow its body temperature to drop and the breathing and heart rate slow right down. In fact, a chipmunk’s heart rate can drop from a frantic 200 to just five beats per minute during hibernation, and fat-tailed dwarf lemurs will only take a breath once every 20 minutes! Hibernation is triggered by seasonal changes within the animal’s habitat. Hibernating species are sensitive to alterations in their environment and can therefore predict the onset of winter. They also produce a hormone called hibernation-specific protein, which prompts the physiological changes needed to conserve energy while in asleep-like state.Prior to hibernating, many animals will eat excessively over the summer months in order to build up a reserve of fat. For instance, bears can consume up to 20,000 calories a day. Some species that hibernate even store imperishable food within their den and wake for short periods during hibernation to eat. Once spring arrives and the temperatures begin to climb once again, the hibernating animal will start to rouse. The length of hibernation varies depending on the species, individual animals and even the weather patterns that year. 

What’s the difference between hibernation and sleep?

Hibernation is a much longer process than sleep, and the animal will go through physiological changes that, although similar to those that occur during sleep, are much more extreme. For instance, warm-blooded animals that hibernate turn almost coldblooded as their body temperature can drop significantly. Their metabolism, breathing and heart rate also slow down dramatically, and they can remain motionless in a coma-like state for days at a time. Waking from hibernation is also a much longer, gradual process when compared to waking from sleep. Sleep itself is also considered more of a mental process, as changes occur to brain activity. On the other hand, hibernating animals have shown brain waves that resemble wakeful brain activity, although they are suppressed. Once an animal wakes from hibernation they will still require a lot of sleep in order to recuperate from the long slumber. In fact, it can take weeks for some animals to recover from several months of hibernation.