Alaska frogs that survive freezing may not survive climate change

Bob Hallinen

Those famous northern wood frogs that freeze nearly solid during extreme cold and then thaw themselves in spring might not fare well in a warming world, say Canadian scientists. The frogs apparently can tolerate only a few freeze-thaw cycles each winter, reports CBC News.

The problem is that the energy molecule used to fuel the freezing and thawing — glycogen — is the same one used by the frog to manufacture the glucose antifreeze that protects its cells from frostbite while the spaces between them are filled with ice. If the glycogen is depleted, the frog won't have enough antifreeze to survive the next freeze-thaw cycle.

[Western University scientist Brent] Sinclair said that means the frog may be vulnerable to changes in snow cover and snowfall that are expected as the climate changes.

In areas where there is less snow cover, the frogs may go through too many freeze and thaw cycles to survive the winter, he added.

Read more at CBC: Frogs burn ample fuel while freezing solid