The 5-4 vote Monday by the New Jersey Marine Fisheries Council dealt a blow to environmentalists and state environmental officials who warn the birds, called red knots, could soon go extinct.
The moratorium, proposed by the state Department of Environmental Protection, would have banned horseshoe crab harvests indefinitely until the red knot population recovered.
"We're all concerned about it," said Joe Rizzo, a member of the council who voted against the moratorium. But he said other factors besides the availability of horseshoe crab eggs could be affecting the birds' survival. "There's just so many other variables," he said.
David Chanda, director of the DEP's Division of Fish and Wildlife, disagreed. He said studies have shown that the birds' survival is directly linked to the number of crab eggs on the beach.
"I'm very, very disappointed in the outcome. Our responsibility for all wildlife is very clear," Chanda said.
Environmentalists and state environment officials argued during the meeting that the red knots' numbers are plummeting and that the ban is the only way to save them.
The red knots, which are listed as threatened in New Jersey, fly from the southern tip of South America to the Delaware Bay, where they feast on the crabs' eggs before flying on to the Arctic where they breed. Without enough eggs, the birds don't gain the weight needed to complete the journey or breed once they get there.
According to Amanda Dey, a DEP biologist, the red knots need about 50,000 horseshoe crab eggs per square meter but she said during the migrating season there are only about 2,000 eggs per square meter. Dey said between 1982 and 2007 the number of red knots migrating through the Delaware Bay declined by about 75 percent.
But the fishermen who have plied the Delaware Bay for years say other factors could be affecting the birds - such as habitat destruction or global warming - and that a limited harvest or a harvest in which only male crabs are collected would not hurt the birds.
Walter Chew, who has harvested crabs and other fish for years, also questioned why state officials were pushing so heavily for the ban when other states were not.
"Why is the department saying we're going to save the world all by ourselves?" Chew said.
Delaware officials tried to implement a two-year moratorium for the 2007 and 2008 seasons, but it was struck down by a court, which said the crustaceans' population was healthy enough to allow a limited harvest. This year, Delaware plans a male-only harvest of 100,000 crabs.
In New Jersey, 39 fishermen currently have licenses to harvest the horseshoe crabs, and some environmentalists questioned whether it was appropriate to risk the future of the red knots for the livelihood of the fishermen. They also see potential for much greater economic gain from tourists who want to see the birds and other wildlife.
Rizzo said the number of fishermen used to be much higher. As state regulators reduced the number of crabs that could be harvested, the number of fishermen dwindled as well, he said.
The fisheries council two years ago approved a two-year moratorium that expired in December. The DEP then proposed the indefinite ban.
Even after the council's decision Monday, it was unclear whether a horseshoe crab harvest would take place. Environmental groups vowed to pursue the matter further, possibly pushing legislators to approve a ban or going through the courts.
"There is no doubt what needs to happen here," said Maya Von Rossum of Delaware Riverkeeper, who said her organization and others would pursue other avenues to protect the birds.
And even Chew questioned whether fishermen would really be able to harvest crabs this spring.
"It's a chess game, and I don't know how to win," Chew said.
