A study predicting wild seafood extinction by 2048 is unfounded and inappropriate, several fishing experts and national fishery regulators said last week, adding to a chorus of local fishing advocates who believe the study is alarmist.

Scientists and regulators said in rebuttals published June 1 in the journal Science that a total collapse of the world's seafood by midcentury is inconsistent with trends in American waters, and in New England, where some stocks are being found in numbers not seen for decades. The journal also published the original study conducted by a group led by Boris Worm of Halifax's Dalhousie University in November.

Hank Soule, general manager of the Portland Fish Exchange in Portland, Maine, said the study pointed to declining catches as evidence the ocean population is also declining, when lower catch is actually a byproduct of stiffer fishing restrictions.

"Take haddock, for example. We deliberately reduced catches in order to help revive the population," Soule said. "Now it's reaching historic levels."

In a collection of letters, scientists and regulators said the study should not have been published in a scientific journal.

"Surely this statement and the specific reference to extinctions of some species must refer to some very limited localities," John Briggs of Oregon State University wrote in the rebuttal. "A thorough study of historic extinctions in the sea published in 1999 showed that no fish species, and only four or five invertebrate species, had become extinct."

Members of the National Marine Fisheries Service, which regulates and oversees the nation's oceans and fishing industry, called the projection "inaccurate and overly pessimistic." A group, led by NMFS Chief Scientific Adviser Steven Murawski, said the study does not take into account recent information showing a rebound in many stocks that had been overfished and were in danger of collapsing.

Ray Hilborn, of the University of Washington's School of Aquatic and Fisheries Sciences, pointed out that many countries, including the United States, Australia, Iceland and New Zealand, have strengthened their fishery management, reducing the number of stocks currently being overfished.

Roger Fleming, an attorney with the conservation group Earth Justice, said government data is expected to show overfishing still occurring on a number of depleted stocks and focusing on the year 2048 misses the point of the article.

"The point of the article is that our oceans are in trouble and there are a lot of depleted fish stocks out there," Fleming said. "The point of Worm's article had more to do with the fact that biodiversity loss is compromising their health and their ability to withstand more of the challenges facing them."

He said the timing of the publication of the responses responses, which had been made when the study originally appeared last fall, is suspicious because it coincides with a New England Fishery Management Council meeting in Portland this week, where the members will begin discussing and voting on possible changes to how New England waters are managed and what restrictions on fishermen will be.

Vito Calomo, executive director of the Massachusetts Fisheries Recovery Commission and a former fisherman, agreed the study is too pessimistic.

The amount of tuna, haddock, cod, mackerel and dogfish being sighted has increased due to heavier fishing restrictions that reduce the amount each fisherman's permit is allowed to land, as well as the number of days that can be spent at sea.

One of the problems keeping some stocks from rebounding as quickly as they could, he said, is pollution, not overfishing.

"If we left fishing unchecked, we'd have a problem," he said. "But we don't. Leaving pollution unchecked is a problem, and it's something we haven't worked to rein in."

The original study, conducted over four years by a group led by Worm, concluded that without changes in fishing rates, the world's oceans could become bereft of usable stocks.

"If the long-term trend continues, all fish and seafood species are projected to collapse within my lifetime - by 2048," Worm wrote. "It is a very clear trend."

A seafood species is determined to have collapsed when the catch falls below 10 percent of the maximum annual haul. By 2003, 29 percent of seafood species were in that category, the scientists said.

The decline in fishing ground stocks can be stopped by the establishment of protected marine reserves, the scientists found after studying 44 such areas. Closing the fisheries and creating reserves led to a 23 percent average increase in species diversity, they said. At the same time, fishing around the reserves became four times more productive.

"We can turn this around," Worm said. "We won't see complete recovery in one year, but in many cases species come back more quickly than people anticipated - in three to five to 10 years. And where this has been done we see immediate economic benefits."