The House yesterday carefully picked its way through a marine mammal protection bill with the result that not as many porpoises would be killed this year as a House committee wanted to allow, but not as many would be saved in future years as the Carter administration and environmentalists wanted, either.

The bill, amending the Marine Mammal Protection Act of 1972, was passed, 334 to 20, in an effort to resolve a dispute between commercial tuna fishermen and environmentalists over the killing of porpoises, which die incidentally because they swim with yellowfin tuna and are caught and drown in the tuna nets.

The Senate has taken no action.

At the time the original act was passed in 1972, an estimated 200,000 to 400,000 porpoises were being killed annually in the taking of tuna.

Though the National Marine Fisheries Service of the Commerce Department was authorized to set a limit on the number of porpoises (or dolphins) that could be killed, no limit was set. However, last year environmentalists took the Commerce Department to court in an effort to force it to set limits and won the case in D.C. District Court. As a result, the National Marine Fisheries Service set a 1977 porpoise kill quota of 59,050.

The action angered the tuna industry, and caused owners of a $500 million fleet of 140 vessels sailing out of San Diego to send out boats and fishermen. The protest lasted for about six months, until May 9 when House Merchant Marine committee Chairman John Murphy (D-N.Y.) assured tuna fishermen on the West Coast a bill liberalizing the porpoise quota would be passed by June 1.

By May 13, most of the fleet had gone to sea relying on Murphy's assurance.

Murphy brought out a bill to increase the porpoise kill quota from 59,050 to 78,900 for 1977. But the bill also would authorize Commerce Department observers to be placed on vessels, provide financial incentives to reduce the kill rate, fine those who exceeded the kill rate and require the tuna industry to provide a research vessel for the Commerce Department.

However, the administration wanted a lower kill quota, and assurances that the quota would be further reduced until it would be 50 per cent of the 1977 level by 1980.It also wanted to ban imports to tuna from foreign fleets that do not comply with the U.S. standards, and shift the cost of the [TEXT OMITTED FROM SOURCE].

The House agreed to reduce the 1977 kill quota server program from the public to the industry, from 78,900 to 68,910, but it rejected an attempt to reduce that quota by 50 per cent in 1980, and instead left it up to the discretion of the Secretary of Commerce.

The vote was 244 to 109.

The House also voted to ban foreign tuna not caught by U.S. standards, but rejected, by 64 to 29, forcing the industry to pay for the proposed observers.

Rep. Paul N. McCloskey (R-Calif.), who offered the administration amendments, argued that the reduction in 1980 was necessary to insure the steady progress to a near zero mortality that the original act required.