BOSTON – A new report indicates Gulf of Maine cod stocks are making a strong comeback, the apparent result of both tight regulation and a hand from nature.

But the good news doesn’t appear to be nearly good enough to prevent even more federal restrictions on fishermen – which some say they won’t survive.

“I don’t know how [more regulation] can be avoided, really,” said Tom Nies, an analyst for the New England Fisheries Management Council, which makes recommendations to federal regulators.

The prospect of more regulation is tough to take when cod is rebounding, said Gloucester-based fisherman Richard Burgess, chairman of the Gulf of Maine Fisherman’s Alliance.

“We were told five or six years ago that once the stocks start recovering, the restrictions will ease,” he said. “There’s no way in the world that will be done. It’s extremely frustrating.”

The report released Wednesday by the federal Northeast Regional Stock Assessment Review Committee shows that the numbers of spawning cod increased from about 10,000 metric tons in 1998 to 23,000 in 2001, a 130 percent increase.

“It’s flat out good news,” said George Liles, spokesman for the National Marine Fisheries Service.

Scientists said a particularly large spawning class in 1998 partly explains the recovery.

But in the same report, scientists say roughly five in 10 adult fish are being taken from the water, a pace too high to ever reach a new federal rebuilding goal for spawning cod of 80,000 metric tons.

Fisherman can take only about two in 10 fish from the water to reach federal mandates by around 2006. In order to do that, stricter controls are needed, Liles said.

But Burgess said fishermen simply can’t take tighter regulations. Most Gulf of Maine groundfishermen are restricted to 88 days at sea annually, with a catch limit of 400 pounds of cod per day.

More regulation means either cutting the number of days at sea, catch limits, or closing additional areas of the gulf.

“There’s a certain few that will survive,” Burgess said. “Ninety-nine percent of the fleet, no.”

Fishermen also are angry about the 80,000-metric-ton goal for spawning cod, which almost triples the total rebuilding target in place last year.

Massachusetts state Sen. Bruce Tarr likens it to changing the rules in the middle of the game and wiping out gains fishermen have made.

“It really calls the credibility of their whole effort into question,” said Tarr, R-Gloucester. “If you want to be Machiavellian about it, it would seem that their overall objective is to reduce fishing capacity and that means reducing fishing boats.”

But Liles said the higher rebuilding target – set to account for recreational catch and by-catch – doesn’t change anything.

It sets a higher goal for cod recovery, he said, but cancels the effect of the increase by assuming more fish are out there. Scientists still hope to reduce the number of fish taken from the water to two in 10, the same as before, he said.

Nies said the numbers in the federal report still need to be reviewed, and any new regulations could be determined by early next year.