Doha, Qatar ? Fishing nations won a victory over environmentalists Thursday when a U.S.-backed proposal to ban export of the Atlantic bluefin tuna was overwhelmingly rejected at a U.N. wildlife meeting.

Japan won over scores of poorer nations with a campaign that played on fears that a ban would devastate their economies. Tokyo also raised doubts that such a radical move was scientifically sound.

In another blow to conservationists, a proposal at the meeting to ban the international sale of polar bear skins failed to pass.

With stocks of Atlantic bluefin tuna down 75 percent from the rapacious appetites of Japanese sushi lovers, the defeat of the proposal was a stunning setback for the Americans, Europeans and their conservationist allies who had hoped the 175-nation Convention on International Trade in Endangered Species, or CITES, would protect the fish.

“Let’s take science and throw it out the door,” Susan Lieberman, director of international policy with the Pew Environment Group in Washington, said sarcastically.

“It’s pretty irresponsible of the governments to hear the science and ignore the science,” she said. “Clearly, there was pressure from the fishing interests. The fish is too valuable for its own good.”

Japan had lobbied delegates hard to kill the proposal. They even had a reception Wednesday night for uncertain delegates that included plenty of bluefin sushi.

When Monaco introduced its proposal Thursday, the gallery was filled with critics who ignored a plea to save the once-abundant species that roams across vast stretches of the Atlantic Ocean and grows as big as 1,500 pounds.

There is an increasing demand for raw tuna for traditional dishes such as sushi and sashimi. The bluefin variety — called “hon-maguro” in Japan — is particularly prized, with a 440-pound Pacific bluefin tuna fetching a record $220,000 last year.

“This exploitation is no longer exploitation by traditional fishing people to meet regional needs,” Monaco’s Patrick Van Klaveren told delegates. “Industrial fishing of species is having a severe effect on numbers of this species and its capacity to recover. We are facing a real ecosystem collapse.”

The tuna defeat came hours after delegates rejected a U.S. proposal to ban the international sale of polar bear skins and parts, suggesting that economic interests at the meeting were trumping conservation.