Their traditional fishing grounds closed in order to ensure the salmon catch of Indians upstream, commercial fishermen from Oregon and Washington moved today toward a confrontation with the U.S. Coast Guard off the Oregon coast.

Nearly 300 boats, mostly owned by local descendants of Swedish and Finish immigrants who have fished these waters since before the turn of century, were reported to be sailing into the zone at the mouth of the Columbia River.

The area has been closed for the next two weeks to commercial fishing. The closure was ordered by the U.S. Department of Commerce until July 1 along a 200-mile-wide strip from 50 the Columbia River, north of to the Canadian border, after biologists forecast that drought and expanded Indian fishing rights might exterminate the chinook and coho salmon species.

Local fishermen said the closure could ruin many of them.

"It's not a question of conservation," said Bob Hudson, a local troller. "It's politics, and we're getting the short end of it."

The closure is an indirect result of court decisions giving Indian tribes along the Columbia's upper reaches a longer fishing season. The expanded rights are new interpretations of peace treaties, some of them signed by British colonialists before the Louisiana Purchase.

Fish biologists say that the increased catch of spawning salmon by Indians earlier this year, coupled with severe drought and subsequent lowering of the river, has substantially reduced the spring fish run to the sea.

The commercial fishermen say the biologists are wrong and their mistake will cost fishermen at least 20 per cent of their annual income.

"It will be hardship for some," said Harriet Engblom, whose husband was defying the ban, and whose ancestors fished these waters in rickety sailing dories."We can only fish six months a year, by law, and losing two weeks at the beginning of the season really hurts."

She said many fishermen could lose their boats, 40-to-50 foot, diesel-driven vessels that represent up to a $200,000 investment for the independent businessman.

"If you have that much at stake, you would be out fighting too," she said.

West Coast salmon trollers sailed Friday to persuade the 9th U.S. Circuit Court of Appeals in San Francisco to reopen commercial ocean fishing immediately.

The court took a troller appeal under advisement, leaving the door open for 200 or more boats to stage the protest of the closure by fishing in a restricted area today.

Coast Guard officers, many of them sons of fishermen, expressed bitterness about their role in preserving fishing restrictions. "We haven't had to do anything like this since prohibition," said Lt. Cdr. Rod Martin, a Coast Guard helicopter pilot.