When the Santa Maria chugged home to this bustling fishing port this week after nine day at sea the eight-man crew of the little boat pocketed $14,800 for the 65,000 pounds of cod, haddock and pollack crammed into her hold.

It was not the first time in this boom year of the new 200-mile limit that skipper Joe Marino and his crew have managed to accumulate such a juicy pot. But this time, when the money was passed out, the smiles and plans for more big cash runs were missing.

Six months after Congress passed the landmark 200-mile restriction on foreign fishermen to save the battered U.S. fishing fleet there is growing concern among the North Atlantic fishing industry that the plan has backfired.

The problem with the new law is not that it hasn't worked but rather that it has worked too well.

Since the 200-mile limit went into effect March 1 and cleared some of the Atlantic's richest fishing grounds for Marino and his colleagues the U.S. fleet has dumped an avalance of fish on the market.

Moreover, the increased catch has spurred a boom in other parts of the industry. Federal experts here said up to 40 new boats - at as much as $1 million each - are under construction because of the boom. Fish precessors here and elsewhere along the Atlantic coast are busy expanding their facilities - building one built in Maine since the 200-mile limit for $750,000.

Now federal fisheries experts say the U.S. catch must be drastically reduced or ocean fish stocks off the New England coast will be critically depleted.

The National Marine Fisheries Service has already clamped a 5,000-pound catch limit on U.S. vessels operating in the Gulf of Maine off the New England coast and next month the limit will be extended to the richest U.S. area of all Georges Bank.

"If we don't do it now we're going to be in bad trouble," said a federal fisheries expert. "The fishermen are depleting the stocks so badly that they are getting like a rancher who slaughters his cattle the day after they're born. We have to control the U.S. fleet for a year or two to build those fish schools back up."

Fishermen here, however, claim their personal experience in sighting unusually large schools of fish this year doesn't jibe win the federal experts' contention. They have reacted to the new catch limits with howls of protest.

"The whole program was put together by people who have never had any experience at sea," said Marino. They're probably all from Ohio."

The problem, federal fisheries experts claim, is that the U.S. fishermen are catching the same species in larger numbers now that were already depleted before the ban on foreign fishing within 200 miles of the U.S. shores. Foreign boats fished for hake, squid and mackeral which are not badly depleted species while the U.S. boats still go after cod, herring, pollack and haddock, all on the government's depleted list.

This week nearly 100 fishermen crowded into the St. Peter Club, a cavernous old bar and meeting hall on the waterfront here, to shout their displeasure at the new regulations to Rep. Michael Harrington (D-Mass.) and federal fisheries experts.

The federal experts are wrong on their ocean stock assessments, the fishermen insisted, and are using the figures and the provisions of the new 200-mile law to move in on the traditionally independent fishing industry.

"There's a million pounds of fish out there and they're telling us we can't touch them," one local fishing boat captain angrily told Harrington.

The federal fish experts agree that this year's catch has been exceptional. But they said despite the plentiful schools of fish on the U.S. grounds, this year long-term stocks of younger fish they have counted show serious depletion that will show up in the future.

Harrington, noting that when the 200-mile limit was first proposed few experts or fishermen believed the U.S. catch would increased to anywhere near its current size, said, "We're in the embrassing situation now of having it better than people thought."

The foreign fleet working U.S. waters inside the 200-mile limit has been halved to roughly 500 vessels, according to the fisheries service. These boats are kept in "windows" or relatively small areas where they are allowed to fish for species not normally sought by U.S. boats such as hake and squid.

The U.S fleet, meanwhile, has increased its catch of cod and haddock, two of the most popular species fished by the fleet, by 50 per cent and 100 per cent respectively.

For Marino and the crew of the Santa Maria that has meant fishing longer and harder to make up for the resultant lower prices. The more they fish, he said, the lower the prices go.

with the rigid quota being imposed on Georges Bank next month, however, the Santa Maria's crew will lose the major source of their fish. "Five thousand pounds," said the 47-year-old skipper, "won't even cover the cost of the gas it takes to make a trip."

Six months ago, he said, the 200-mile limit law was greeted here with cheers. "At the time it looked like we had it made," he said. "Now the men would rather see it go back to the old way with the government out of our business."