"It really just alerts the world that its condition is worsening," said Dave Jenkins, chief of the Department of Environmental Protection's Endangered and Nongame Species Program.
The proposal comes just as research in the last month shows that the bird's numbers have dropped further still and that the horseshoe crab it relies on for food is beginning to recover.
To Eric Stiles, conservation director for New Jersey Audubon, the proposed change "means we need to do more."
All migrating shorebirds are in trouble, and these red knots top the list. But unlike the crabs they feed on, the knots serve no specific use for humans other than to provide an annual spectacle of nature. Which surely is one reason crabbers and others are resisting some efforts to save it.
The knot is a robin-size shorebird that has one of the longest migrations on the planet, from the tip of South America to its Arctic breeding grounds.
Partway through this 10,000-mile flight is the bird's most important refueling stopover: Delaware Bay. In May, just as the birds arrive, multitudes of horseshoe crabs are swarming ashore to lay their eggs in the sand.
This lipid-rich food is considered vital. The knots need to gain weight quickly so they can reach the Arctic and reproduce before early snows.
Once numbering 90,000 on the bay, the birds have declined to less than a fifth of that. Biologists blame an aggressive harvest of horseshoe crabs, which are used as bait for whelks, a delicacy in Asia.
Crabs also are captured and bled for the biomedical industry. Their blood is used to detect toxins in various products. But most of these crabs survive and are released.
New Jersey's proposal to change the knot's listing is based on data several years old. It simply took a while for the state to amass enough evidence of changes in other species to warrant the bureaucratic process.
A public comment period lasts until March 19.
In late February, biologists returned with sobering news from their annual trip to the bird's wintering grounds in Tierra del Fuego, Chile.
Immense flocks of red knots once swooped over the vast tidal mudflats, rich in tiny organisms that were a nonstop banquet. In recent years the number declined to 16,000, but remained stable.
Now, the count showed the population dropping again, to between 10,000 and 11,000.
"We're dismayed," said Larry Niles, former chief of the DEP endangered-species program, now a wildlife consultant. He has led red knot research for more than a decade.
The crew of more than a dozen international researchers had hoped for an uptick because conditions on Delaware Bay last spring were so favorable. The weather held, the crabs laid their eggs, the birds feasted.
Data from netted birds showed that nearly 80 percent were at or near ideal body weight, prime for breeding.
Meanwhile, fisheries officials say they are noticing early indicators of an increase in the crab population.
The Atlantic States Marine Fisheries Commission, an interstate regulatory body, has enacted increasing restrictions on the harvest of horseshoe crabs - not for the crabs, which are not in trouble, but for the birds.
States can take more restrictive measures, and New Jersey has had a moratorium for a few years.
The population is monitored largely by surveys using trawlers that net crabs.
The most recent surveys have shown an increase, mainly in juveniles, which the commission said was "indicative of population recovery."
But government funding ran out. To keep the surveys going, the biomedical industry chipped in $100,000. Rick Robbins of Virginia-based Chesapeake Bay Packing L.L.C. coordinated $15,000 in aid from the seafood industry.
Robbins, who has argued against restrictions, called the current crab regulations "extremely risk-averse."
But Niles and others say it is a race against time.
The New Jersey moratorium is helping, "but it's too slow," said Amanda Dey, principal zoologist with the DEP program. "We're still holding our breath."
The Chile count was so low they can hardly believe it.
They will learn more in May, when the knots once again return to Delaware Bay.
Contact staff writer Sandy Bauers at 215-854-5147 or firstname.lastname@example.org.
Visit her blog at www.philly.com/greenspace