Australia's Christmas Island used a bridge to solve road mortality for 50 million migrating crabs; the result transformed dangerous transit routes into safe canopy crossings

Millions of red crabs undertake an annual migration across Christmas Island. This remarkable journey begins with the first rainfall of the wet season. Male crabs lead the trek, and females join them for mating near burrows. Females then spawn eggs which hatch into larvae in the ocean. Baby crabs eventually return inland to mature over several years.