The Gulf of Mexico continues to gush oil just as a whaling controversy threatens to land Australia and Japan in international court for killing protected species. Meanwhile, another less-publicized but arguably more cataclysmic oceanic disaster continues to worsen.

Overfishing threatens to destroy most of the world's fisheries within a matter of decades. But while it's proven difficult to save the gulf or save the whales, we know how to save the fish: Stop treating the ocean like a public bathroom, says Christopher Costello, a professor of natural resource economics at UC Santa Barbara.

Director Louis Psihoyos and his team of filmmakers embarked on an elaborate sting operation to expose Japan's illegal dolphin hunters. The result is a documentary called The Cove, which took home the Oscar for best documentary. And days after the Academy Awards Psihoyos was back stirring things up.

Using the same cameras that were used to expose illegal dolphin hunters, Psihoyos and his team busted The Hump, a Santa Monica, California restaurant that had secretly been serving sushi made from the endangered sei whale.

"Everything in the ocean from the great whales to dolphins to plankton is being jeopardized," Psihoyos tells Reason.tv. "We're raping and harvesting the ocean unsustainably."

Overfishing "could mean the end of certain species," agrees UC-Santa Barbara's Costello. He points out that about a third of the world's fisheries have already collapsed, and many more are heading toward the same fate. Costello says the world's fisheries are in such bad shape because of the same reason public restrooms are typically foul places: "Nobody owns them. Nobody has the incentive to keep them up."

One proven solution is a system called "catch share," in which fishermen have the right to a certain share of the total catch of a type of fish. This form of ownership gives fishermen an incentive to make sure fish populations grow, and according to Costello's worldwide research, it's the only thing that seems to work.

Environmentalists are often suspicious of the profit motive, but from Alaska to New Zealand, market forces have been harnessed not for plunder but for preservation. Fishermen like the system because they make money, and environmentalists like it because it supports sustainable practices. Expanding the catch share system may well be the best way to save a dying ocean.

"How to Save a Dying Ocean" is written and produced by Ted Balaker, who also hosts. The associate producer is Paul Detrick, the cameramen are Hawk Jensen and Alex Manning; Zach Weissmueller also helped to produce the segment. Animation by Hawk Jensen.

Approximately six minutes.

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