It's the first warm day of April. The sun is shining on frosty leaves littering the ground near the edge of a pond. Huddled under leaves against a fallen log, a tiny hibernating frog feels the slight change in temperature. As the air about him warms, he wriggles out of his winter nest, hops around, and finds his way to the water. He fills his throat with air from his lungs, making the skin beneath his mouth look like a balloon being blown up.

"Bre-e-e-e-p!" he calls. Spring has come to his world.

Minnesota has 14 species, or kinds, of frogs and toads. All across the state, millions of frogs and toads spend the cold season—from about October to March or April—hibernating in the ground or under water, rocks, logs, or fallen leaves. As the air and water cool, their body temperatures drop. Some frogs and toads freeze solid, like ice cubes.

With not much going on inside them, frogs and toads can survive on tiny amounts of air that filter into their bodies. Then, when the weather warms, they wake from their long naps. Their chirps, croaks, and snores fill the air as they begin a new cycle of life.

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