This is a topic circulating on TeenBirdChat at the moment . . . this scare anybody else?

Tyler Davis, 18
Mercer Island, WA
didjkid at aol.com

REEDS BEACH, N.J. - For nearly a decade, scientists worldwide have been watching this marshy corner of the Delaware Bay, predicting an ecological nightmare.

A tiny shorebird known as the red knot descends here every spring to feast upon iridescent green horseshoe crab eggs to fuel its long flight to mate in the Arctic. But in a vivid example of the precariousness of the food chain, as the numbers of helmet-shaped crabs have declined, so have the birds.

This cold, unforgiving spring, researchers' worst fears have been confirmed: The red knot population on the bay has plummeted to 16,255, less than half that of last year. Birds have pecked the sand for crab eggs, and finding few, will likely die on their flight to nest up north.

Extinction is imminent, scientists say.

"This year seems to be the beginning of the great drop-off," said Larry Niles, chief of the state's endangered and nongame species program, who hosts a group of shorebird scientists from Australia, England, Canada and the Netherlands every year at Reeds Beach in Cape May County.

"We believe the red knot is like the passenger pigeon - you see a lot of them, and then you see none. There is a scientific model predicting extinction by 2010. After this year's decline," he said, the timetable may be accelerated.

If the birds disappear, so may the $34 million spent annually by bird-watchers who flood Cape May and Cumberland Counties to observe the migration of five different shorebirds dependent on horseshoe crab eggs, according to the New Jersey Audubon Society. The numbers of ruddy turnstones, sanderlings, least sandpipers and semipalmated sandpipers also have dwindled, but none as dramatically as the red knot.

Environmentalists and researchers alike blame the decline of the tawny-breasted birds on the overharvesting of horseshoe crabs. The crabs, which date to prehistoric times and are actually a member of the spider family, can fetch more than $1 apiece from eel and conch fishermen eager to use them for bait.

A clotting agent in the crabs' blood also makes them valuable to the biomedical industry, which uses them to screen for toxins in drugs and medical equipment.

In April, both New Jersey and Delaware imposed emergency regulations cutting the horseshoe crab harvest in half, to 150,000 on each side of the bay, and banning fishing in May and June, the birds' migration season.

New Jersey's regulations still stand. But Delaware's were struck down in court last month after a group of four fishermen challenged them on procedural grounds. Delaware's Division of Fish and Wildlife is working to draft permanent regulations, but fishermen are free to collect the crabs off the state's beaches this year.

"Crabbers from both sides of the river are rushing to take advantage of Delaware's predicament," said Tim Dillingham of the American Littoral Society, a Shore conservation group based in Sandy Hook. "I've heard reports of crabs spilling out of overloaded pickup trucks onto the highway."

On the other side of the bay, on the jetty at Reeds Beach, scientists and volunteers in lawn chairs sit in three teams, recording information about the red knots as shorebirds swoop down around them. Calling out data in a flurry of accents, workers trap 300 palm-sized birds at a time and pass them on to be banded for future identification, equipped with radio transmitters, and weighed and measured.

This same routine has taken place since 1998. Scientists know there were more than 50,000 birds on the bay then, compared with the 16,255 found this year. In 1998, nearly 34,000 birds attained the minimum 6-ounce weight needed to survive the journey to the Arctic, compared with 5,376 last year.

This year, just three or four birds out of every 24 had gained sufficient weight to make the 2,000-mile flight north.

More shorebird studies are going on in the Delaware Bay than anywhere else in the world, Niles said.

In contrast, little is known about horseshoe crabs; researchers can only guess at their population numbers. New Jersey studies have shown that the concentration of green eggs on the beach has declined by 50 percent since the 1990s, but Delaware reports that the crab population has stayed stable in recent years, just not large enough to sustain migrating birds. Compounding problems this year has been the cold, wet weather, which has delayed the spawning season of the crabs.

Most fishermen argue that the horseshoe crab population is healthy.

"The regulators' science is not sound - the bird people are pulling the wool over their eyes. My watermen are reporting a thick population [of crabs] this year," said Tim Willard, the Delaware attorney who challenged the rules in court. "The horseshoe crabs aren't to blame for the birds not gaining weight. They came late this year, after the egg party was over," he said, referring to the crabs' peak spawning period last weekend. The birds' visit to this region is expected to end this weekend.

The group of international scientists who study the birds during the winter in South America and in the summer in the Arctic have urged officials in both states this year to abandon harvesting quotas and declare a moratorium. Horseshoe crabs do not reach sexual maturity for nine years, they say, and the population needs to be given time to recover.

"Only one factor that affects the birds has changed while their population has dropped, and that's the availability of crabs here," said Clive Minton, a researcher from Australia. "The only way to reverse it is a moratorium for at least five years, allowing the crabs to breed."

The New Jersey Department of Environmental Protection's endangered species advisory committee is also likely to call for a horseshoe crab moratorium, said Jim Applegate, a Rutgers professor and longtime panel member.

"I don't know if the shoe is fundamentally dropping or if this is an off season for the birds, but we need to err on the side of caution," Applegate said. "We had a moratorium on striped bass in the 1980s, and it was tremendously successful. If we can constrain a fishery as strong as striped bass, surely we can constrain bait for eel."

If the Delaware Bay continues to dry up as a source of food for the migrating red knots, their days are numbered, Niles said. Areas heavy with horseshoe crabs in Virginia are too far south to fuel the Arctic journey, and food is scarce farther north.

This year's red knot numbers reinforce theories that the birds' path to extinction is accelerating, said Allan Baker, a professor at the University of Toronto.

"This place, the Delaware Bay, had always been the birds' insurance policy, the crown jewel in the flyway on the way to the Arctic," Baker said. "But now the population is ready to crash, and extinction will follow."