Georges Bank is a huge underwater island - 20,000 square miles and as large as the state of Massachusetts - that lies just below the surface of the Atlantic Ocean.

The bank is part of the continental shelf. More than 10,000 years ago, geologists believe, the bank was a high and dry island.

As the ocean rose, the island was submerged. Fish love the bank because it is a great source for food. Water depths are not much more than 100 feet and sometimes as shallow as 20 feet. Light from the sun penetrates to the bottom and supports a world of microscopic plankton that fish eat.

The bank is far more productive than the deeper ocean to the south and east, supporting more than 100 species of fish from the groundfish that include cod, haddock, hake and flounder to fish such as red fish, which inhabit the canyons in deep water.

The ecosystem of Georges Bank stretches out to other areas, including the Gulf of Maine to the north, and also well south of the Vineyard.

For a long time, the ecosystem worked. Fish from the bank fed more than one nation.

But over the past five decades, American and foreign fishing fleets have fished Georges Bank hard, taking more fish than in past decades or even centuries.

Today some of the bank's seemingly inexhaustible fish stocks are exhausted. They include cod, a groundfish that has long been a staple for Europeans and Americans.

U.S. fishery managers have tried plan after plan to revive or at least preserve cod stocks on the bank, but with little success.

The latest plan to end overfishing is Amendment 13, which was prepared by the New England Fishery Management Council, and adopted by the National Marine Fisheries Service in May 2004.

The amendment lists 12 groundfish stocks that are either overfished or have been declared overfished in the past. The impact of the amendment's stricter regulations now are being felt by commercial fishermen.

When council members met last week, they received an update on fish stocks on Georges Bank and in the Gulf of Maine.

In the coming months, the question they will ask themselves is whether they have done enough in the last round, or if even more extreme measures should be adopted.

The fishing effort they will analyze has varied over the decades on Georges Bank.

Last century, up until World War II, the bank was fished mostly by Canadian and U.S. fishermen.

Soon after, following advances in technology, foreign fishing fleets began arriving from Europe.

Fishing boats were more than 200 feet in length, with nets the size of football fields capable of harvesting vast amounts of fish on the bank. The boats could catch, process and freeze their fish all on one vessel.

From 1961 to 1976, at least three principal distant-water fleets other than Canadian vessels worked the bank. The boats hailed from the Union of Soviet Socialist Republics, Spain and Poland.

According to National Marine Fisheries Service records, from 1965 to 1966 the U.S.S.R. took a total of 30,000 metric tons of cod. From 1967 to 1969 Spain took 42,000 metric tons of cod, and during the same period Poland took 6,000 metric tons of cod.

Fishing on Georges Bank also was intense for other species, including hake, mackerel and herring.

In the 1970s, scientists estimated that the cod spawning stock size was 90,000 metric tons.

In 1976, the United States established a 200-mile federal limit that would keep the foreign fishing fleets away from Georges Bank. Congress simultaneously enacted the Magnuson-Stevens Fishery Conservation and Management Act to manage fisheries within the 200-mile limit around the nation.

Canada objected that the 200-mile limit would keep its fishermen off Georges Bank. The case went to the World Court.

In the court's 1982 decision, the United States was awarded jurisdiction over most of Georges Bank, but Canada was given purview over the northeastern corner. Because the World Court is based in the Hague, Netherlands, the line became known as the Hague Line.

Since the division, American fishermen have claimed that Canada got the best corner of the bank; at the same time fisheries scientists claim that Canada also imposed a much harsher fisheries regulatory plan to protect the fish.

Coincidental with the closing of Georges Bank to foreign fishing fleets, the federal government offered subsidies and incentives to American fishermen to cash in on access to the bank. The first thing many fishermen did was acquire larger and more efficient fishing boats.

Critics say that expansion of the fishing fleet has curtailed efforts to constrain fishermen from overfishing the bank.

In 1980, scientists estimated the cod spawning stock at 92,000 metric tons.

Then in 1991, the Conservation Law Foundation - a regional environmental advocacy organization that has kept a close watch on fisheries management - filed a lawsuit against the National Marine Fisheries Service, charging the agency with failing to follow the terms of the Magnuson Act. The foundation won the case.

The result was a number of initiatives to restrict commercial fishing on the bank.

In 1995, scientists estimated cod spawning stocks on Georges Bank at 17,000 metric tons, the lowest point since estimates had begun.

In 1996, Congress amended the Magnuson Act by adopting the Sustainable Fisheries Act. The act calls on fisheries managers to prevent overfishing and sets goals for reviving depleted stocks to a sustainable state.

Fisheries managers closed huge areas of Georges Bank to trawlers. They also established days at sea, a limit on the number of days a fishing boat can pursue groundfish.

In December 2001, the Conservation Law Foundation and other organizations successfully filed a lawsuit against the National Marine Fisheries Service charging the service had failed to adhere to its own mandate to reduce fishing. The case ultimately resulted in the current management plan, known as Amendment 13.

In 2001, the cod spawning stock was estimated at 29,000 metric tons.

Regulators estimated that fishermen on Georges Bank caught 13,000 metric tons in 2001. Fishermen were charged with taking too many fish, but they countercharged that the scientific data used to establish the number of fish on the bank was flawed.

In September 2002, one fisherman raised questions about the effectiveness of the trawl survey based on marking errors in the two cables that ran out to the net.

The controversy surrounding the net aboard the research vessel Albatross IV out of Woods Hole became known by its nickname, Trawlgate.

Fishermen said the errors marred the federal assessments. They said the cod were out there, but the Albatross IV was not counting them. A subsequent lengthy study proved no measurable difference.

The controversy did raise questions about the effectiveness of the trawl survey over the long term, and ironically, Trawlgate helped spawn a new partnership between scientists and fishermen.

An advisory group was established to work on trawl surveys in the years ahead. Fishermen, industry experts and scientists plan to design a new trawl survey system to replace the one used aboard the Albatross IV.

A new research vessel, the Henry B. Bigelow, was launched July 8. The 208-foot vessel is scheduled to go into service next year. After test and trials she will replace the Albatross IV, which was built in 1963.

For a sustainable fishery, scientists say cod biomass must be built up to 217,000 metric tons on the bank. They say once that goal is reached, fishermen will have access to more fish than they have seen in years. At that level, scientists say fishermen can harvest 35,000 metric tons a year without hurting the fishery.

The concept is akin to putting money in a bank, with the idea that eventually you only draw on the interest.

In late August, the National Oceanographic and Atmospheric Administration's Office of Sustainable Fisheries released its 2004 report on the status of fish stocks.

The office listed cod, haddock, winter flounder, yellowtail flounder, white hake and American plaice as both overfished and still facing overfishing.

Last week, the New England Fishery Management Council officially received the report at a meeting in Providence, R.I.

The report included estimates through 2004 on the health of the resource. The estimates tapped half a year of fishing data under the constraints of Amendment 13.

The estimates, which describe the continued overfishing of cod, worry fishery scientists. Those worries were foreshadowed in a paper submitted last year to the Bulletin of Marine Science by a team of scientists.

"Substantial reductions in fishing mortality are needed to rebuild the cod stocks," scientists wrote in the publication. "Both the Gulf of Maine and Georges Bank cod require more than a 50 per cent reduction in fishing mortality to achieve the rebuilding fishing mortality target."