Local dragger fishermen Vito Giacalone has supplemented his income from catching groundfish in past years by selling spiny dogfish that wind up in his nets.

In the past, the federal government has allowed fishermen to catch up to 600 pounds of spiny dogfish per trip until 4 million pounds of the small sharks were caught in a year. But the National Marine Fisheries Service closed the fishery last week because federal regulators disagreed with a decision by fish managers from the Atlantic states to raise the annual dogfish quota to 8.8 million pounds in state waters, a move championed by Massachusetts officials.

The change has converted a usable fish to bycatch or discards -- in effect, the very waste that regulators have been court-ordered to eliminate.

As a result of the policy changes, Massachusetts fishermen who fish in the first three miles off-shore, water governed by the state, will be able to catch about 5.1 million pounds of dogfish this year, an 57.9 percent share of the quota allowed the three northern New England states.

But fishermen like Giacalone, who has federal permits and works in the area stretching from the boundary of state waters to 200 miles off-shore, are shut out of the fishery.

Giacalone expects to lose some money as a result of the federal closure. He will have to throw back dead any dogfish that are caught in his otter trawl net.

"You're going to convert what would have been landings into discards," he said.

Federal researchers at the Northeast Fisheries Science Center in Woods Hole said in an advisory report released last week that rebuilding spiny dogfish would take at least 15 years.The study estimated that fewer pups have been born in the last seven years because the ocean holds fewer and smaller females. The pups that are born have a low survival rate.

NMFS officials believed they had to close the fishery last Friday in order to continue rebuilding the depleted dogfish population, said NMFS spokeswoman Teri Frady. NMFS felt it couldn't allow fishermen to catch more dogfish after the Atlantic States Marine Fisheries Commission raised its quota from 4 million pounds to 8.8 million pounds in February.

The Atlantic states commission voted last month to maintain that new allocation, a move that concerned William Hogarth, the head of NMFS.

"By instituting a directed dogfish fishery in state waters, the commission is jeopardizing the health of a stock that is already in serious trouble," he wrote in a July 3 letter to the commission.

David Pierce, deputy director of the state's Division of Marine Fisheries, shares Hogarth's concerns about the health of the dogfish population, but he believes fishing can continue in a restricted manner that protects the adult females crucial to the sharks' reproduction. He said the Atlantic commission used the same science as NMFS to craft its dogfish quota, but the commission thought estimates of discards and Canadian catches should not be factored into the quota because no one knows how accurate these estimates are.

"It's not science, it's a matter of policy," he said. "We don't want to shut down the dogfish fishery because of bycatch in other industries."

Spiny dogfish meat is used in British fish and chips. Local gillnet fisherman Dave Marciano said dogfish are vicious predators that compete with cod and other groundfish to eat herring and feed on juvenile cod, creating a nuisance for fishermen. Dogfish often clog his nets or eat groundfish caught in them, he said.

"They didn't get this abundant by being docile," he said. "They eat the cod, they eat the cod's food."

But environmentalists like Sonja Fordham, shark specialist for the Ocean Conservancy, said spiny dogfish, one of the most abundant sharks, need to be protected because of their slow reproductive biology.

Female spiny dogfish don't bear their first live pups until they are 12 years old and they carry a litter -- averaging six pups -- for nearly two years, she said.

Because fishermen have targeted the large females in order to receive more money for a larger fish, scientists are finding smaller numbers of dogfish pups.

"Rebuilding will take 20 years in the most optimistic scenario," she said. "It's really bleak."