They concluded that about 26,000 red knots came to Delaware Bay this spring — nearly double that of the last few years, albeit still a long way from the 100,000 red knots that once crowded the Bayshore beaches.
"This is kind of an unprecedented situation," said Amanda Dey, principal zoologist with the New Jersey Department of Environmental Protection, who has studied red knots for years.
But it can be difficult to get people to care about a bird, even one that may be listed soon as an endangered species by the U.S. Fish and Wildlife Service. So now the red knot is becoming the star of an even bigger show — the Delaware Bayshore itself.
Advocates realize that the crab, the bird, and the Bayshore are inextricably linked, their fates intertwined.
The Bayshore now has a Facebook page called "Celebrate Delaware Bay," a social marketing campaign, a series of YouTube videos, and, coming this month, a book celebrating "this unique ecological gem that lies hidden in plain sight in the most densely populated section of the country," as the authors note.
This spring on Facebook, shorebird researchers gave daily updates on their work with red knots.
The social marketing campaign, shepherded by the Manomet Center for Conservation Sciences, a Massachusetts nonprofit, is aimed at getting more people to know and appreciate the Bayshore in their midst and, ultimately, to do things that would benefit it — including activities as simple as not disturbing the birds while they eat.
Charles Duncan, director of Manomet’s shorebird recovery project, became a convert to social marketing when he saw what it did in a small town in Argentina, where some red knots winter.
Most of the townsfolk didn’t know or care about the birds. But marketing techniques that included a song and a mascot helped produce a shorebird festival and shorebird murals on public buses. People stopped driving their four-wheelers on beaches where the birds roosted.
"It felt like for the first time in a long time, someone had handed me a new tool with which to do conservation," Duncan said. Clearly, science alone wasn’t enough.
This month, Rutgers Press is releasing the book Life Along the Delaware Bay: Cape May, Gateway to a Million Shorebirds written by zoologist Dey, fellow researcher Larry Niles, and Rutgers University professor Joanna Burger. It includes more than 300 photos by Jan van der Kam, a wildlife photographer from the Netherlands.
"We wanted to give voice to the bay," said Niles, chief wildlife biologist with the Conserve Wildlife Foundation of New Jersey.
Last Tuesday, the Bayshore got another boost when U.S. Interior Secretary Ken Salazar came to Delaware’s tiny Slaughter Beach — the town flag shows a horseshoe crab — to announce the Bayshore’s inclusion in the national "American Great Outdoors" initiative.
As 300 guests slapped at another signature bay species, biting flies, Salazar called the Bayshore "a landscape of national significance."
Delaware Gov. Jack A. Markell and other state officials talked about the importance — and the economic benefit to the small Bayshore towns — of preserving the shoreline from Delaware City to Lewes, marked by ecologically vital coastal marshes, beaches, farms, and forests.
About 60 percent of it is protected, and officials highlighted more than two dozen projects to preserve more and add amenities for revenue-producing recreation and ecotourism.
Delaware Bay has been celebrated before. A quarter century ago it was named a site of hemispheric importance by an international shorebird conservation group.
Not long after, the shorebirds began to decline. Larry Niles, then a biologist with the state Department of Environmental Protection, wanted to find out why. He tracked the birds from South America to the Arctic and eventually concluded that increased harvest of horseshoe crabs on Delaware Bay was to blame.
The helmet-shaped crabs, an ancient species, are used as bait for eel, a popular delicacy in Asia.
But the crab’s fatty eggs are a vital food for the shorebirds that arrive on the bay every spring famished and emaciated. They need to nearly double their weight in a matter of weeks so they can get to the Arctic, breed, and get out before the late-summer snows.
As the crab harvest rose, red knot numbers fell. Sanderlings, ruddy turnstones, and semipalmated sandpipers also have declined.
The crabs themselves were never in trouble. But eventually, New Jersey placed a moratorium on the crab harvest. The Atlantic States Marine Fisheries Commission has enacted restrictions that apply to other states, including Delaware, whose moratorium was struck down in court.
Officials say this is the first time a fishery species is being regulated not for its own benefit, but for that of a bird.
This year, the researchers noticed many juvenile red knots, a sign of breeding success in 2010, along with a welcome infusion of birds.
"But what matters most is that we had more eggs, and the birds are just in beautiful condition," Niles said. "It reminds you of times long ago."
Researchers catch the birds to tag them, weigh them, and get other data. This year more birds gained more weight than any time since 1998.
Researchers mostly credit the weather with this year’s successes. They don’t yet know if harvest restrictions have boosted crab numbers.
Bulkheads and beach erosion, which reduce crab spawning areas, also are part of the equation. Many projects now target beach restoration.
Another wild card is the biomedical industry. Horseshoe crab blood has a substance that can indicate contamination, and it is widely used to assess the safety of drugs and medical devices.
Horseshoe crabs are captured, partially bled, then released. But some die, and shorebird biologists fear a face-off with powerful drug companies as the need for more crab blood increases.
Yet they also hope to find common ground — both sides see value in maintaining a strong crab population.
The successful spring on the Bayshore "reminds you of what has been, and what can be," said Eric Stiles, president of New Jersey Audubon.
Still, one good year does not a recovery make. As welcome as the new infusion of birds was, said the DEP’s Dey, "we have a long way to go before we have 100,000 red knots again."
Contact Sandy Bauers at 215-854-5147, email@example.com, or follow on Twitter @sbauers. Read her blog, GreenSpace, at www.philly.com/greenspace