Horseshoe crabs are not really crabs, but are more closely related to spiders or scorpions. They are of great ecological interest as their eggs form an important portion of the diet for a number of migratory seabirds; young crabs are prey for many other invertebrates and fish; and adults form a portion of the diet of loggerhead sea turtles and sharks. They are of commercial importance because a component of their blood is critical to one process for testing the sterility of medical supplies. For further details please see Horseshoe Crab (PDF).
Research and monitoring of these organisms is conducted by the Crustacean section. Data on horseshoe crab have been recorded from regular trawl sampling conducted inshore and offshore since 1995. A compliance report (PDF) is submitted annually to the Atlantic States Marine Fisheries Commission (ASMFC) detailing observations made from sampling and monitoring a biomedical facility.
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