Each year a small shorebird must make a 10,000-mile journey from the southern tip of South America to its nesting grounds in the Arctic – one of the longest migrations on earth. This pocket-sized long distance traveler times its migration precisely to coincide with the annual spawning of one of earth's most ancient creatures: the horseshoe crab. It's horseshoe crab eggs on the Delaware Bay that fuel the little bird’s epic journey to the Arctic. In the 1990s the fishing industry discovered that horseshoe crabs make good bait for eel and conch. As these industries boomed, horseshoe crabs were collected by the truckload...and red knot numbers started to crash.