The limits are to be implemented by May 1 and represent a compromise between the demands of fishermen and conservationists, said Tom O'Connell, coordinator for the crab management plan. Drafting the policy was difficult because scientists still lack much basic information on the crabs, he said. Under the plan, states would have to devise methods to cut their catch and compile data needed to assess the health of the species. The biomedical industry has its own reasons for wanting to curb the harvest of crabs for bait. The horseshoe crab's blood is used in a process to detect bacterial toxins that can contaminate drugs and medical equipment.
Blood is extracted and shipped to labs and then the crabs are released.
The crustacean is also used for vision studies because its complex eye structure is similar to the human eye. The coastwide plan was needed because the trawlers that scoop up horseshoe crabs by the thousands in federal waters simply avoided the few states that imposed regulations, conservationists said. The crabs could not be unloaded in Delaware and New Jersey and were restricted in Maryland, so the bait industry shifted to Virginia, which had no regulations on how many horseshoes could be brought to the docks. Virginia has about 50 conch boats and the state exports about 80 percent of conch caught in the Atlantic. Conch fishermen use horseshoe crabs for bait, impaling them on spikes in their traps.