Horseshoe crabs, a species dating back about 450 million years, usually scuttle ashore to mate on East Coast beaches this time of year, a breeding season that lasts until mid-June. But hundreds of thousands of the crabs are instead captured and bled for biomedical uses before being returned to the ocean. The ordeal removes them from the mating pool for several days and, the research suggests, may ruin the mood when they return.
The study found that crabs that have been bled become disoriented. It suggests several measures that the crab-bleeding industry should embrace: keeping the crabs in cold water during their captivity, and ending harvesting during the mating season. Those two steps would maximize the number of crabs on the beaches this time of year, and hopefully lessen the trauma for the crabs that are captured.
Protecting horseshoe crabs isn’t just a matter of good environmental stewardship. Crab blood has unique medical capabilities, and the crab population needs to be managed like the public health resource that it is. A component in crab blood can be used to test vaccines for harmful bacteria, and the FDA requires that vaccines and implanted medical devices pass a test derived from crab blood.
While bleeders should take steps to treat horseshoe crabs better, regulators may also need to crack down on non-medical uses. Currently, horseshoe crabs are also used as bait for eel, conch, and whelk. But preserving a medical resource should take precedence over supporting a commercial fishery, even if other baits aren’t as effective. In several mid-Atlantic states, harvests are restricted to only male crabs, and New Jersey put a moratorium on horseshoe crab harvesting in 2008.
As Massachusetts well knows, efforts to preserve fish stocks can quickly become adversarial when fishermen start to see environmental protections as a threat to their livelihood. But keeping the crab population healthy is in the fishing industry’s best interests, as well.