The photographs in this gallery are of Horseshoe Crabs Limulus polyphemus and their eggs. These images were taken in Delaware Bay, home to the largest population of the American species of Horseshoe Crab (three other species exist in coastal waters between Japan and Indonesia). As the tide comes in on moonlit nights in May and June, thousands of crabs appear on the beaches in Delaware Bay to lay their tiny green eggs, just as they have done for 450 million years! The eggs provide a lifeline for the thousands of waders (shorebirds) that use Delaware Bay as a staging post on their northward migration to their breeding grounds.
Due to their design, the waves can flip crabs onto their backs and leave them stranded on the sand, unable to right themselves. Locals and visitors to the beaches spend many hours rescuing stranded crabs, particularly the larger breeding females, but many die through exposure to the sun. Sadly, crabs can also be caught in discarded fishing equipment, as the photo in this gallery shows.
Read more about the crabs and their importance to humans and birds on the Nature Conservancy website.