for at least 11 species of migratory shore birds, including the red knot, which relies strictly on horseshoe crab eggs for food during migration. Many fish species as well as birds have been observed feeding on horseshoe crab eggs in Florida. . Some males (called satellite males) do not attach to females but still have success in fertilizing the female's eggs as they crowd around the attached pair. Bang suspected this clotting had a purpose. The animals are most abundant in estuarine waters, where they feed on algae, marine worms, clams and other mollusks, and dead fish. Horseshoe crab, (order Xiphosura common name of four species of marine arthropods (class Merostomata, subphylum Chelicerata) found on the east coasts of Asia and. Often this leads to the death of the animal (you can help them by gently picking them up from both sides of the shell and releasing them back into the water.) Other observers have mistaken horseshoe crab molts for dead crabs. . (For reasons not entirely understood, horseshoe crabs are only found around the eastern coasts of North America and Asia.) Bang, a pathologist, was interested in the creatures primitive immune system.
The marine life fishery collects live horseshoe crabs for resale as aquarium, research, or educational specimens, and the American eel and whelk fisheries use horseshoe crabs as bait along many parts of the Atlantic coast. These pincers are used to grab the food and push it toward the mouth. Many people have seen horseshoe crabs but do not realize they are looking at one of the oldest animals on the planet. Horseshoe crabs commonly get overturned by high wave action during spawning and may not be able to right themselves. . Biomedical applications The American horseshoe crab is harvested by the commercial fishing industry for use as bait to capture American eels ( Anguilla rostrata which in turn are used as bait for striped bass ( Morone saxatilis and whelks. Amebocyte refers to cells in the crabs blood. Horseshoe crabs are known for their large nesting aggregations, or groups, on beaches particularly in mid-Atlantic states such as Delaware, New Jersey and Maryland in the spring and summer, where their populations are largest. Instead, gently pick it up by both sides of the prosoma using both hands. Best known is the single American species. They are about 5 mm (0.2 inch) long, have no telson, and live off a store of yolk. Behind the bases of the last legs is a pair of reduced appendages called chilaria. Horseshoe crabs have a tank-like stucture consisting of a front shell called the prosoma, a back shell called the opisthosoma, and a spike-like tail called a telson. .