Adult foxes prefer to sleep in the open, even in the middle of winter. It was the immortal amphibian, Kermit the Frog, who said it s not easy being green. But for most frogs, being green isn t nearly as rough as surviving winter by becoming frogsicles. Ice crystals form in their bodies, causing the partially frozen frogs to stop breathing and their hearts to stop beating. Fortunately, sugar in their blood acts as an antifreeze, preventing vital organs from freezing solid.
Aquatic frogs swim deep underwater and lie on a muddy pond bottom or hide among plant matter.
Terrestrial frogs sometimes dig holes under the soil, below the frost line. Others look for deep cracks in logs or rocks, or bury themselves in leaves. Although the frogs come close to freezing, they don t croak. When the temperature warms up in spring, the frogsicles thaw out. Their hearts resume beating, their lungs resume breathing, and their legs resume hopping.