There are more mammals that hibernate. Wood frogs, like salamanders, do. They reduce their metabolism and seek shelter from the cold. During hibernation, the wood frog's heart stops beating and 35-45% of its body freezes.
These frogs go through a freeze-thaw pattern multiple times during the winter thanks to a unique natural substance in their blood. In good weather they thaw and begin the feeding and mating process again.
Toads and newts also go into torpor in cold weather.
Although it may seem curious to you, other animals that also hibernate are birds, dormouses, turtles, rabbits, bats, marmots, insects, snails or snakes.
