MIDDLE TOWNSHIP, N.J. (AP) — Oyster farming is the kind of business an environmentalist should love: it doesn't use harmful chemicals or deplete natural resources, and the locally grown shellfish actually help clean the water.
It's a green, sustainable industry that brings nearly $1 million a year to growers in the New Jersey Delaware Bay area and puts shellfish on restaurant plates around the northeast.
But when that industry sits on the lone feeding ground in the western hemisphere for the largest population of a threatened species of shorebird, things get complicated.
New Jersey's oyster aquaculture industry is centered on the same Delaware Bay beaches that provide irreplaceable feeding grounds for the red knot on its annual 10,000-mile journey from South America to the Arctic. And that has environmentalists worried, particularly given the extensive efforts to restore Delaware Bay beaches damaged by Superstorm Sandy in 2012 that have succeeded in stabilizing the red knot population, albeit at lower levels.
A decision this month by the U.S. Fish and Wildlife Service allows oyster growers to expand their operations on the beaches, including some spots that host the largest concentrations of red knots. While the goal is to concentrate farming in the southern range of the beaches, which tend to be wider and have more space to share, additional growers can be approved to enter the northern zone, as well, where more of the birds congregate.
"This is exactly the wrong direction to head in when we're starting to see the first glimmers of hope on Delaware Bay," said Tim Dillingham of the American Littoral Society, one of several groups that helped restore the narrow beaches at the state's southern tip.
The 17 farms in the area produced 1.6 million oysters in 2014, the most recent figures available, bringing just under $1 million to growers, according to Dave Bushek, director of the Haskins Shellfish Research Laboratory at Rutgers University.
"I think there's very easily room for both of these things to coexist," he said.
Lisa Calvo, a program coordinator at the lab and a commercial oyster grower herself, said the farmers and the environmentalists are on the same side.
"We were always fully supportive of measures to protect the red knots," she said. "The industry is building a brand based on the reputation of being environmentally responsible."
Larry Niles, one of the nation's leading experts on shorebirds, said the Delaware Bay population of red knots has declined from 90,000 in 1986 to 23,000 today, due in large part to drastic overfishing of horseshoe crabs in the early 1990s. In addition to being used as bait by commercial fishermen, the crabs are milked for a substance in their blood that's useful to the pharmaceutical industry. New Jersey has since banned horseshoe crab harvests, but the damage has been done. In 1990, there were about 12 million horseshoe crabs in the bay. There are now about 4 million, Niles said.
The eggs that the crabs lay on the beaches are rocket fuel for arriving red knots which are exhausted and emaciated from their journey from the southern tip of Chile. The birds gorge themselves on crab eggs during their May stopover, replenishing themselves for the second leg of their journey to the Canadian Arctic, where they breed.
The birds are skittish and easily disturbed. But the farms need to be tended, some daily. The mesh bags in which the oysters grow need to be turned and washed to eliminate parasites that can harm or kill the shellfish. Walking or riding all-terrain vehicles out to the bags, which are suspended several inches off the mud flats on steel racks, can disturb the birds and injure or crush crab hatchlings.
Environmentalists also say the more metal racks placed between the shore and the water, the more difficult it is for the crab hatchlings to make it to the ocean and survive. But Calvo said she has observed crabs moving in and around the racks with no difficulty.
Bushek, the shellfish laboratory director, said the oyster farms use "a fraction" of the available habitat for red knots.
"The industry is in more danger of being eliminated than the red knot is," he said.