East Coast Reins In Horseshoe Crab Catch

Horseshoe crabs outlived the dinosaurs, but some scientists worry that their resilience is being tested beyond their limits.

Inedible to humans, horseshoe crabs have been harvested in large numbers in recent years because they are the most effective bait for conch.

A recently imposed 25% reduction in horseshoe crab harvests along the Atlantic Coast, from Florida to Maine, has the conch industry in a panic.

“It’s going to hit us hard,” said Rick Robins, whose seafood packing company exports about $3 million in conch meat annually.

Conservationists, on the other hand, say the regulations are a baby step that may do little to protect the species. They worry that a crash in the horseshoe crab population would, in turn, decimate many migrating shorebirds, which feast on the crabs’ eggs.

One species of sandpiper, for instance, flies nonstop from Brazil to Delaware Bay to fuel up on the horseshoe crab’s metallic-blue blood, or “green caviar,” before heading to the Arctic to breed, said Gerald Winegrad of the American Bird Conservancy.

“There’s no question that shorebirds are in decline because of the horseshoe crab harvest. It’s an utter waste of a resource,” said Winegrad, who would like to end the harvest but lobbied for a 50% reduction.

Certainly not the prettiest creature in the ocean, horseshoe crabs nonetheless are evolutionary wonders that have survived for 250 million years, partly because they can go a year without eating and endure extreme temperatures and salinity.

Once called horsefoot crabs because of the resemblance of their shell to a horse’s hoof, they have no claws, multiple legs and a pointed tail. During spawning season, their eggs smear the beaches, particularly in the Delaware Bay region, which is home to the largest population of American horseshoe crabs.

Considered the junk of the sea for much of human history, the crabs were ground for fertilizer from the 1800s through the 1960s. They have a life span of at least 20 years, but because of their slow sexual development--it takes females 10 years to reach maturity--it could take years for their population to bounce back if overfished.

The restrictions approved by the Atlantic States Marine Fisheries Commission represent the first coast-wide cap on the crab harvest.

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.

“Until recently, horseshoe crabs were considered a nuisance, an ugly critter, so nobody was collecting data on them,” 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 coast-wide 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 or 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% of conch caught in the Atlantic. Conch fishermen use horseshoe crabs for bait, impaling them on spikes in their traps.

“We don’t have any alternative bait sources,” said Robins, of Chesapeake Bay Packing in Newport News, the largest exporter of conch in the United States.

But conservationists believe that conch fishermen could cut their bait use in half by putting it in mesh sacks, something Virginia conch fishermen have begun as part of a pilot program.