Many commercial fishing stocks off the United States coast that were depleted by decades of overfishing are returning to abundance, thanks largely to a 1996 law that effectively ordered limits on catches until the fish populations had rebounded, a newly released analysis of federal data on fish populations states.
The analysis, by the Natural Resources Defense Council, concludes that 21 of 44 species that it studied have met rebuilding targets and 7 others have made significant progress, increasing their populations by at least 25 percent.
Sixteen have made less or no progress, the report stated, including 10 species off the New England coast, most of them popular bottom-dwelling fish like cod and flounder. In half of those cases, the fish populations had grown by more than 25 percent but were still being overfished.
All have been managed under the 1996 law, the Magnuson-Stevens Fishery Conservation and Management Act, which sets a 10-year target for rebuilding each species.
Brad Sewell, a lawyer for the resources group and the main author of the analysis, said the uptick in fish populations was especially impressive in light of what he called a dismal record in most other parts of the world.
"When you look at the population trajectories of dozens and dozens of stocks, you see '96 as a real watershed," he said "You see this cause and effect between implementing the law and the upward population trajectory."
The report noted that between 2008 and 2010, the average revenues from catches of the 28 fish that made the most rebuilding progress had jumped 54 percent, allowing for inflation, from the start of their rebuilding.
The report's calculations are based entirely on annual reports on fish stocks issued by the National Marine Fisheries Service. The service has labeled 124 species overfished, but the report focused on 44 for which there were enough data to draw conclusions on their rebuilding progress.
Mid-Atlantic fish stocks reported the most progress; all seven species examined had met population targets, including bluefish, black sea bass and summer flounder. Many New England stocks also recovered fully, including sea scallops, haddock, monkfish and yellowtail flounder.
But many other New England fish were recovering more slowly, mostly because of overfishing and environmental problems, Mr. Sewell said. Until recently, he said, New England regulators had set targets only for total catches instead of setting strict quotas under which any excess catch would be deducted from the following year's quota.
Six of the eight species that made the least progress are off New England, including Atlantic cod, winter flounder and ocean pout. And even some species making slightly better progress, like the slow-growing Atlantic halibut, could take decades to rebuild, he said.
"They were the size of small boats, and they virtually went extinct," he said. "They're coming back. But it will be a long haul."
This article originally appeared in The New York Times.