The International Whaling Commission said yesterday that it will allow Eskimos to kill 18 bowhead whales next year, six more than this year.

Richard Frank, a U.S. member of the whaling commission, said the quota was increased because scientists estimated that the world bowhead population is 2,264 whales, almost twice the previous estimate. The old number was based on out dated figures from environmental impact statements. The current estimate was based on a recent census by scientists who counted the whales as they migrated.

Commercial hunting of the endangered bowhead whale is prohibited. Eskimos hunted the whale without regulation until last year, when the International Whaling Commission - spurred by conservation groups - first imposed a moratorium on Eskimo hunting of the bowhead, and six months later said Eskimos could kill 12 of them.

Under the whaling commission's 1979 quota, Eskimos can take 18 whales or wound 27, whichever occurs first. The 1978 quota was 12 whales taken or 18 that were struck but got away.

Eskimo representatives denounced the quota as unnecessary and an intrusion into their way of life. They said Eskimos have been killing whale for 7,000 years, taking only enough for their needs and never endangering the whales' survival.

"The natives should be left alone," said William Byler, executive director of the Association of American Indian Affairs. "They have a social informal means of making sure that whales aren't needlessly killed."

During the past 10 years, Eskimis have harvested an average of 24 whales a year. Scientists have estimated that the bowhead whale population has increased by between 45 to 100 whales each year.

"If there's going to be a quota at all, why not have a quota of 88 whales instead of 18?" Byler said. "It won't hurt the whale population."

But the whaling commission and a conservation group - the Whale Protection Fund - said the quotas must be conservative because the whale is still endangered.

Kata Bouve of the Whale Protection Fund said her group approved of the 18-whale quota: "The quota could have been a lot worse - a lot higher," she said. "It's the fault of commercial whaling that the bowhead is endangered, and it's too bad that the Eskimos have to pay for it, but there isn't much choice."

The International Whaling Commission, which met in London last week, also decided to take away the protected status of the California gray whales because the "stocks are healthy at the present time," Frank said. But the United States will continue to oppose commercial hunting of the gray whale.