It's rush hour in Philadelphia for thousands of baby toads as they hop across a busy residential street on a rainy summer night.
Why do toadlets cross the road? To get to woods on the other side. It's their annual migration through dense vegetation from an abandoned reservoir where they were born.
To help the tiny amphibians survive the trip, volunteers each year set up the Toad Detour. The roadblock reroutes cars so the animals—each about the size of a raisin—can cross the two-lane street safely.
The detour also goes up during mating season. Each spring, adult toads travel from the woods to their breeding ground at the reservoir.
About six weeks later, their offspring make the journey in reverse.
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