Education Corner: Hibernation
Arriving at the Greenway in the early morning frost it is hard not to marvel at how our wildlife survives the freezing winter nights. At an early age we learn that some animals ‘hibernate’ to survive the winter. Hibernation is a fascinating event that can range from ‘torpor’, a very light extended sleep, to a full on 8-months of not waking up. During hibernation, animals can slow their heart beat and lower their body temperature, using the absolute minimal amount of energy.
One extreme example of this is the wood frog – a cold-blooded or ectothermic animal whose body temperature matches its surrounding environment. Where most frogs hibernate deep under water to avoid having to drop their body temperature below freezing, the wood frog nestles just beneath the forest leaf litter and allows itself to freeze, in the truest sense of the word. Ice crystals form in the blood and muscles and the heart stops beating. The wood frog becomes a solid frog of ice. Then, in the spring, the frog starts to thaw out and miraculously the heart starts beating again and the wood frog is able to move about.