It is one of those exquisitely choreographed moments in nature: A small bird on its way from the bottom of the world to its breeding ground at the top encounters its nutritional lifeline as it lands on sandy beaches along the Delaware Bay.
Red knots arrive from South America, exhausted and emaciated. Horseshoe crabs swim from sea to shore, following their prehistoric instinct to procreate.
They get together each spring for their annual date, a two-week springtime feast and orgy that has been performed longer than humans have been recording such things.
The robin-sized bird gorges itself on the fatty eggs laid by the crab to replenish its body and stock up for the remaining leg of its flight. It needs to consume 18,000 eggs a day; a single female horseshoe crab lays 90,000 BB-sized eggs each spring.
Lately, however, red knots have been finding the cupboard bare. Commercial fishermen, in a frenzy of their own, scooped up millions of horseshoe crabs to sell to the bait industry, using pitchforks to pile the helmet-shaped creatures into pickup trucks. In 1990, the harvest was 1.2 million crabs. Eight years later, regulators stepped in to limit the harvest, but the damage was done.
The crab population plummeted. The red knot population decreased at an alarming rate. As a result, scientists and birders who used to see 100,000 red knots feeding on the Delaware Bay in the 1980s now see fewer than 15,000.
"The birdfeeder of the Delaware Bay is empty," says Perry Plumart of the American Bird Conservancy.
Eight environmental groups filed a lawsuit Tuesday in federal court in New Jersey to force the U.S. Fish and Wildlife Service to place the bird on the endangered species list. But it may be too late.
One population model suggests that the red knot could be extinct as early as 2010.
As with the force that brings the red knot and horseshoe crab together, timing is everything.
"We are up against the wall if we are to save this species," says Jason Rylander, a lawyer for Defenders of Wildlife. "And we are running out of time."
On a humid day in late May, an international group of scientists and volunteers hunker in the tall marsh grass where the ticks crawl and bite.
About 100 yards away on a sliver of beach on the Delaware Bay, 1,000 birds are feeding.
Suddenly, an explosive charge booms and echoes off the water. A tea-colored net arches skyward and falls to the sand, trapping about 100 birds beneath it.
"Run!" someone shouts, and in a blink the people in the weeds sprint to the shore. A tarp is placed over the net to quiet the birds. Then, as they roll up the net and tarp, they reach under to pull out birds. Gulls are released. The migratory birds, including 24 red knots, are placed in boxes and carried to an improvised work area behind the dunes.
Larry Niles, head of New Jersey's Endangered and Nongame Species Program, oversees the bustle, but his work force clearly knows what it is doing.
"There is no way this bay could support 100,000 birds now," he says. "We're at 15,000 birds ... That's a lot of birds by bald eagle standards, but for shorebirds, that's too low."
At the diminished level, the genetic pool is too small to sustain a hit by severe weather, disease or catastrophic loss of habitat.
New Jersey officials, alarmed by the decline of the bird, close 15 beaches during the red knot stopover period and last month imposed a two-year ban on all horseshoe crab harvests. Delaware wildlife officials lack the authority to do so; an attempt several years ago was successfully challenged in court by watermen. Maryland and Virginia - the two states nearest the Delaware Bay - have done little to protect the crabs.
In May, the regional regulatory body that sets catch quotas for creatures such as striped bass, flounder and horseshoe crabs rejected a request from conservation groups to follow New Jersey's lead. Instead, it enacted a two-year ban on the taking of female crabs. That, say red knot supporters, is not enough.
The horseshoe crab takes nine to 13 years to reach sexual maturity. Because of the massive harvest of crabs in the late 1990s, the species, although not in trouble, isn't producing enough eggs to feed the red knot. Concentrating the commercial harvest on males will not allow horseshoe crabs to rebound to levels found in the 1980s and earlier.
But the Atlantic States Marine Fisheries Commission isn't in the bird business. It is in the fishing business, and keeping commercial interests financially healthy is part of that equation.
"We keep waiting for someone to step up," says Niles. "The ASMFC undermined [New Jersey's] moratorium, and that makes it difficult for other states to act."
Ared knot is an amazing creature by any standard, but as a migratory bird it is almost unsurpassed.
To get from its wintering grounds near Tierra Del Fuego, Argentina, to its breeding grounds in the Arctic Circle, the russet-breasted bird flies 10,000 miles. On the first leg, the bird hugs the coast of South America, stopping occasionally to feed. But when it reaches Brazil, it pushes off on a 4,000-mile, four-day, nonstop flight to reach Delaware Bay.
On takeoff, it weighs about 6 ounces. By the time it lands, a red knot weighs half that. To refuel in flight, it consumes its own muscle and organs.
At Delaware Bay, it has about two weeks to fatten up for its nonstop flight to the Arctic.
"Then the biological alarm clock rings and it has to take off, ready or not," says bird conservationist Plumart.
Even if the bird reaches its breeding grounds, weather conditions might be too severe, or the bird may be too weakened, to ensure survival.
Ornithologists say the red knot is one of the most studied birds in recent history. Monitoring stations have been set up in South America and northern Canada. Bird watchers on the Atlantic coast e-mail their reports to scientists. Biologists have gone in search of small flocks in Virginia and Florida.
So when skeptics say the red knot has relocated rather than disappeared, the birds' protectors shake their heads.
"They'd have to be missing a very long way to be lost," says ecologist Humphrey Sitters.
For more than 20 years, scientists and volunteers have patrolled prime stopover beaches as part of the Delaware Bay Shorebird Project. For some, it is a continuation of their life's academic studies. For others, it's a birding hobby that has turned into a passion.
Each May, many of them are drawn to a ramshackle house on the New Jersey side of the bay, near where the red knots gather. . They come from Mid-Atlantic states but also Britain, Japan, South America, Australia and New Zealand.
They have come to save the birds.
Researchers watching the birds in their wintering spots say the numbers appear to have increased slightly.
That doesn't impress Sitters, an Oxford-educated ecologist who abandoned his law career to track the birds.
"The model says if the adult population remains static, extinction is possible," he says. "The adult survival rate of 75 to 80 percent has been replaced by a survival rate of 55 percent."
As Sitters talks, people weigh and measure the red knots. Others clip tiny feathers and place them in plastic bags for later study. A scientist from Argentina takes blood samples. Finally, each bird is banded, carried to the beach and released.
As a curtain of humidity turns the sky and water a gunmetal gray and lightning etches the scene, the pace quickens.
Amanda Dey, a senior biologist who works with Niles and is co-leader of the shorebird project, says other volunteers are helping protect the birds on the beach. They shoo away beachcombers and scare off dogs. If need be, they call state conservation officers.
But a shield of bird enthusiasts doesn't pack the wallop of a protective layer of law. That's why conservation groups last summer asked the U.S. Fish and Wildlife Service to use its emergency powers to place the red knot on the endangered species list.
In December, the agency dismissed the petitions. Diane Lynch of the Endangered Species Division says the emergency provision is invoked only when "within a year that species would be functionally extinct.
"The bar is quite high and rightly so," she says.
Lynch acknowledges that certain proposals - such as the one before the fisheries commission for a harvest moratorium - were unsuccessful.
"There's nothing to say that we cannot look at that species again," she says of the red knot. "We are waiting to see the [Delaware Bay] counts and the wintering counts this year."
Just last week, the Delaware Bay Shorebird Project released its preliminary count this year: 13,000 red knots.