Overfishing hurts birds

ON THE BAY

Danger: Virginia's insistence on catching an excessive number of horseshoe crabs for conch bait can mean that migratory shorebirds go hungry.

April 14, 2000|By Tom Horton | Tom Horton,SUN STAFF

VIRGINIA PRIDES itself on state's rights, but if ever there was an advertisement for federal control, it is our bay neighbor's destructive, cynical and stupid insistence on overfishing the horseshoe crab.

Destructive, because the eggs of the crabs, which spawn throughout the Chesapeake but most heavily in Delaware Bay, are vital to many of the Western Hemisphere's migratory shorebirds.

Great flights of red knots, ruddy turnstones, palmated sandpipers, dowitchers, sanderlings and other species travel up to 5,000 miles each spring between South America and northern breeding grounds.

In May and June, timed to the crabs' spawning, the birds, often literally skin and bones, arrive on Delaware Bay beaches and marshes. Feeding largely on the tiny, gray-green horseshoe eggs, they double their weight in a few weeks or less -- "so fat it's like they are spread with butter," said a biologist who autopsied shorebirds departing northward several years ago.

Ironically, the eggs are low in nutritional value. Researchers calculate that to gain the weight it needs for migration and reproducing, a bird must eat an egg every five seconds during 14 hours a day of foraging.

Some scientists speculate that the shorebirds might not have been so dependent on the low-energy crab eggs until destruction of coastal habitats diminished other stopping places and food.

The critical thing is that the birds need a whole lot of eggs. And in recent years the eggs have been in ominous decline, as commercial catches of horseshoes -- mainly to bait conch pots -- have doubled and doubled again.

Scientists and volunteers who have done informal surveys for years estimate that the spawning crabs on Delaware Bay -- the world's greatest concentration of the species -- have fallen from more than a million in 1990 to less than half that.

"The spawning used to go on for two months and on every beach, and now it's down to just a few prime beaches and mostly on the peak times, the new and full moons," said Bill Hall, a University of Delaware Sea Grant expert on the crabs.

The birds need "a superabundance" of spawning crabs so that waves of crabs, coming ashore to bury eggs in the sand, dig up and make accessible billions of eggs buried by earlier spawners, said Kathleen Clark, a zoologist with New Jersey's Fish and Wildlife agency.

She said that this year, for the first time, her agency found birds departing northward that had not gained as much weight as usual.

"You used to see wrack lines on every beach just thick with exposed crab eggs, and now that is a rare sight," Clark said. The adult birds may survive this, but if reproduction is diminished, then at some point the population will crash, she said.

Now for the cynical part. Under a conservation plan agreed to by 14 other Atlantic coastal states, Virginia's harvest would have been 152,495 crabs. But it plans to take 710,000. This will wipe out the effect of deeper-than-required cuts made by states including Maryland and New Jersey.

Virginia said it needed more "sound science" to act. Everyone agrees that more science needs to be done to understand how to manage horseshoe crabs on a long-term, sustainable basis.

But the evidence is compelling, and the risks are great. Horseshoe crabs were fished down earlier in the century and took decades to come back.

What drives Virginia is less a lack of science than a profitable fishery for conchs that has sprung up in the past five years. Horseshoe crabs are by far the best bait.

The conch fishery employs about 50 boats part of the year. Virginia seafood processors say conchs are worth several million dollars a year to them. They threatened to sue if Virginia complied with the conservation plan, and the state backed down.

Virginia is also mindful that a full-throttle conch fishery takes pressure off beleaguered blue crabs. " `You put us out of conching and we'll be right back into crabbing' is what the watermen tell us," said Lewis Gillingham of the Virginia Marine Resources Commission.

Asked whether the current conch fishery represents overfishing, Gillingham said the state has implemented conservation measures but lacks the science to answer that question -- "kind of like with the horseshoe crab," he said.

Essentially, Virginia is buying another year for its conch industry and evading its conservation responsibilities.

The state knows that the federal government can impose limits and that it is also moving to restrict horseshoe crabbing in federal waters off Delaware Bay, where most are caught.

The state also knows that these actions probably will take the rest of the year to wend through the bureaucracy.

Which brings us to Virginia's stupidity. Even now, it could be lobbying "bait bags" used in other states that would let conch fishermen halve the crabs they need (the protective bags make bait last longer).

Instead, it will most likely use the full 710,000 crabs this year. And if limits are imposed, Virginia will have to "pay back" all crabs caught above the 152,495 allotted by the conservation plan.

That could mean shutting down the state's conch industry. If it happens, don't expect anyone outside Virginia to shed tears.

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