EASTHAM, Mass. (AP) -- Three cannons explode on a deserted Cape Cod beach, unleashing a startling cloud of white smoke and sand. In tandem, projectiles erupt from the ground, flinging a net over a group of elusive shorebirds known as red knots.
A dozen wildlife researchers emerge from hiding and sprint to transfer the prized catch into holding boxes and then to a camp nearby. There, they collect feather samples as they measure, weigh and tag the robin-size birds, then fit their legs with tiny geolocators and release them.
Biologists hope the geolocators will use ambient light to calculate and record the locations of the rosy-breasted birds, helping conservation workers who will recapture them to determine their migration routes and refueling stops.
The red knot is already on New Jersey's endangered species list and has been proposed for inclusion on the federal list. It's known for its South America-to-Arctic migration, a 10,000-mile flight.
The population has dropped by up to 75 percent since the 1980s in some areas, according to the U.S. Fish and Wildlife Service. The decrease is partly fueled by a drastic decline in the horseshoe crab population in Delaware Bay, a key refueling stop during their migration to the Arctic breeding grounds.
Red knots may also be vulnerable at areas where juveniles spend their first winter away from the Arctic, said Stephanie Koch, biologist for Eastern Massachusetts National Wildlife Refuge. Identifying those locations will enable experts to evaluate if they are protected and secure enough for the species.
The plight of the red knots highlights a bigger problem.
"We've been focusing on the knot because there's big migration, this is a flashy shorebird, but 70 percent of shorebird species are in decline," said Lawrence J. Niles of the Conserve Wildlife Foundation of New Jersey. "It's the stopovers. ... If they don't have them, then they either can't make it down or can't make it back."
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