After years of failed attempts, a cohort of Oregon Zoo-reared northern leopard frogs has finally survived through the winter. Here's what changed.

The wood frog, with no heartbeat or brain activity, thaws back in spring and hopes its way after a freeze period as if nothing happened.

In other words, adult turtles that can’t fit in the frog’s mouth. An American bullfrog tadpole (left) is bigger than the young native northwestern pond turtle on the right of this photo.

Crawfish frog numbers are on decline due to habitat loss. But scientists in Indiana are working to return species to a historic site.