The two Soviet fishing ships, their cargoes seized, American flags flying over their rusty gray hulls, somehow looked said tied helplessly to the Coast Guard pier here today.

Only the press and official visitors are allowed close to the ships, but along the waterfront, in the local media and among the New England congressional delegation, the gloating has been hard to conceal.

Since the Coast Guard two weeks ago was ordered by the White House to release a Soviet trawler allegedly carrying illegally caught fish these quarters have been crying loudly for seizures to enforce the new 200-mile American fishing zone law. Even President Carter has said the Americans are "drawing the line."

Much of this reaction, however, appears to have been overblown. Coast Guard records indicate the the line already had been drawn, the enforcement has been tough, and, despite the cries for blood, most of the violations have been minor.

"I question whether a lot of these violations are significant enough to qualify for seizure," said William Gordon, northeast regional director of the National Marine Fisheries Service and a leader in the fight that created the 200-mile zone. "In part, there has been a lot of confusion switching from one regime to another, and in part many of the violations have been minor."

What is being overlooked, many officials say, is that the new law provides for administrative fines imposed by the fisheries service as an alternative to seizure, and act which is weighty under international law. The fines are for up to $25,000 per violation per day.

In the first six weeks of the law, the Coast Guard has reported 40 such violations for which such fines have been recommended. The fisheries service is still processing the recommendations, ablut half of which involve Soviet ships.

During March alone, the Coast Guard also has issued 75 warning citations in boarding 155 ships, twice as many boardings as a year ago though there were only half as many foreign boats fishing off American coasts.

Local Coast Guard commanders recommending seizures were overuled in at least three instances by the White House.

But officials say the confusion involves where to draw the line between imposing an administrative fine and seizure. In the three cases where ships were released, all of them involving Soviets, one had 130 pounds of illegally caught fish. Another had about 220 pounds and the third was a support ship that did not have a permit, gisheries officials said.

"Nothing is definite," said Lt. Cdr. Thomas Nunes, head of enforcement in the Atlantic. "I don't feel our recommendations for seizures are made lightly. We feel we have a job to do and we try to do it under the law."

Some officials in the State Department, however, feel the Coast Guard is too quick to recommend seizure. They say this is partially a leftover from the past several years when seizure was the only enforcement method available when foreigners were caught taking lobster, crab ad like species which were the only ones ordered under American jurisdiction before the 200-mile law.

The older jurisdiction led to 19 seizures last year, Coast Guald officials say. One was a Soviet vessel seized for having 30 pounds of lobster, or about 15 lobsters. The Soviets settled, out of court for $400,000.

"Sure, we used to seize them with one crab," said Vice Adm. Austin C. Wagner, commander of the Pacific area.

Seizure under the new law can lead to civil or criminal charges and penalties of $50,000 fines, six months in jail and confiscation of the ship.

The Coast Guard fleet in the Atlantic has been more aggressive in enforcing the law then the one in the Pacific, fisheries officials say. Of the 73 warning citations issued last month, for instance, 73 were in the Atlantic.

Following a briefing by the Coast Guard, U.S. Attorney James Gabriel said today he "can only hope that I will have the information needed to make a decision by Wednesday" on whether to press charges.

The Coast Guard is taking an inventory of the fish in the Antanas Snechkus' holds and examining entries in its logs. Other documents found on the ship and on the Taras Shevchenko also are being examined.

"We don't have any course of action plotted out yet.

"It's exactly like any other individual charged with a crime. If we decide to press charges, we'll file a complaint in District Court and he [the master of the Soviet ship] will appear. If bail is set I assume it will be paid and he will come back at a later time for his trial."

Asked how long the ships could be detained without charges being brought, Gabriel said "the law says for a reasonable period of time and reasonableness in this case depends on a lot of facts."