When mating season arrives, these frogs melt
Wood frogs spend the winter in a remarkable state: frozen, yet still alive. Once they thaw in spring, they head for ponds to find breeding partners.
During winters in North America, many amphibians dive or burrow deep to avoid freezing—but not the wood frog. These fig-size croakers stay put aboveground as the water between their cells freezes, and they spend the season in a kind of cryosleep.
When spring arrives, most wood frogs awaken from their icy slumber with one thing on their mind: sex. Males find a pond or temporary vernal pool and call to females with sounds “almost like a quacking duck,” says Dartmouth College’s Ryan Calsbeek, a biology professor who studies amphibians’ sex lives. As more males join in, the cacophony of croaks can be heard throughout the forest.
Hearing the come-ons from the ponds around them, females hop toward the