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Will Killing Whales Save the World's Fisheries?
Despite anything you may have heard to the contrary, whale meat does not taste good. I know from experience: as a reporter in Tokyo I once attended a whale food festival — there were whale noodles, whale sashimi, fried whale, whale on crackers — put on by Japanese whaling industry lobbyists for the country's legislators. But for all its forbidden mystique, whale meat tastes spectacularly bland — the sort of food you might eat only if there were nothing else available.
And that happens to be exactly why whale became a significant part of the Japanese diet, as a cheap source of protein in the impoverished days following World War II. As the country grew wealthier, however, whale meat grew less popular. Still, Japan (along with Norway and Iceland) continues to hunt and kill whales — more than 800 in the 2006 to 2007 season — and is pushing for an end to the 22-year-old worldwide ban on commercial whaling. While industry supporters contend that it's necessary for food security, today the average Japanese eats a little more than an ounce of whale meat per year, which puts a damper on the argument.
So in recent years the whaling industry has been trying out a different defense — that whale populations need to be culled to reduce their threat to fast-disappearing fish stocks. Whales, after all, eat a lot of seafood, so it would make sense that controlling whale populations would be smart "ecosystem management," as whaling supporters put it. But a new article in the Feb. 13 issue of Science demonstrates that's hardly the case. "Essentially what we found was that...if you remove whales, it has a negligible impact on the biomass that is commercially available for fishing," says Leah Gerber, a conservation biologist at Arizona State University and the article's lead author. Translation: killing whales won't resuscitate depleted fisheries.
The reason is that marine ecosystems and food webs are far more complicated than the one-to-one predator-and-prey relationship we might expect. Analyzing the waters off Western Africa and the Caribbean, where baleen whales breed, Gerber and her colleagues mined marine data to create ecosystem models that plotted the feeding interactions between whales and fish. (They chose these waters in part because Japan is using the fishery argument to persuade Caribbean and African nations to support the lifting of the whaling ban.)
The models allowed the scientists to test what would happen if whale populations declined. It turned out that whale numbers had little impact on commercial fish populations, in part because the kind of sea life whales like to eat — krill, plankton — is highly unlikely to end up on your dinner plate. "The seafood that people prefer is higher on the food web than [whales' diet]," says Gerber. There's also the undeniable fact that today's whale populations are still just a fraction of what they were in the days when Captain Ahab was (unsuccessfully) whaling, yet commercial fish populations are still dwindling.
The International Whaling Commission is set to meet in a few months, and Japan and its allies will once again push for an end to the commercial ban — an appeal the Science analysis significantly undermines. But one fact of the Japanese argument is undeniable: the world's commercial fisheries are in serious trouble, and they're getting worse. In new research presented at the annual meeting of the American Association for the Advancement of Science on Feb. 12, the marine ecologist William Cheung announced that climate change would have a devastating impact on the world's commercial fish and shellfish populations, including tuna, herring and prawns. Fish would flee toward the poles to escape rising temperatures, and many species would all but disappear from their familiar habitats. Many would not survive the transition — Cheung estimated that the Atlantic cod's distribution could drop by up to 50% by 2050 thanks to climate change. "The scary thing is that this isn't just happening in the future," he says. "We're seeing similar things happening now."
Preserving commercial fisheries isn't as simple as culling whales — it isn't simple at all. But if the world's fishing nations fail to curb overfishing and protect endangered marine habitats, in the end, whale might be all we have left to eat — and trust me, you won't like it.
