Passage 3 Will Killing Whales Save the World’s Fisheries?
捕鯨能挽救世界漁業(yè)嗎？ 《時(shí)代周刊》
[00:00]For all its forbidden mystique,
[00:03]whale meat tastes spectacularly bland the sort of food you might eat only
[00:09]if there were nothing else available.
[00:12]And that happens to be exactly why whale became a significant part of
[00:17]the Japanese diet, as a cheap source of protein in the impoverished days
[00:23]following World War II. As the country grew wealthier, however,
[00:29]whale meat grew less popular.
[00:32]Still, Japan (along with Norway and Iceland) continues to hunt and kill whales
[00:38]more than 800 in the 2006 to 2007 season and is pushing for
[00:45]an end to the 22-year-old worldwide ban on commercial whaling.
[00:52]So in recent years the whaling industry has been trying out a different defense
[00:58]that whale populations need to be culled to reduce their threat
[01:02]to fast-disappearing fish stocks. Whales, after all, eat a lot of seafood,
[01:09]so it would make sense that controlling whale populations would be smart
[01:14]"ecosystem management," as whaling supporters put it.
[01:19]But a new article in the Feb. 13 issue of Science demonstrates
[01:25]that's hardly the case. "Essentially what we found was that...
[01:30]if you remove the whales, it has a negligible impact on the biomass
[01:35]that is commercially available for fishing," says Leah Gerber,
[01:39]a conservation biologist at Arizona State University
[01:43]and the article's lead author.
[01:46]Translation: killing whales won't resuscitate depleted fisheries.
[01:52]The reason is that marine ecosystems and food webs
[01:57]are far more complicated than the one-to-one predator-and-prey relationship
[02:04]we might expect. Analyzing the waters off Western Africa and the Caribbean,
[02:11]where baleen whales breed, Gerber
[02:14]and her colleagues mined marine data to create ecosystem models
[02:19]that plotted the feeding interactions between whales and fish.
[02:24]The models allowed the scientists to test what would happen
[02:29]if whale populations declined. It turned out
[02:33]that whale numbers had little impact on commercial fish populations,
[02:38]in part because the kind of sea life whales like to eat - krill,
[02:44]plankton is highly unlikely to end up on your dinner plate.
[02:50]The International Whaling Commission is set to meet in a few months,
[02:55]and Japan and its allies will once again push for an end to
[02:59]the commercial ban an appeal the Science analysis significantly undermines.
[03:06]But one fact of the Japanese argument is undeniable:
[03:11]the world's commercial fisheries are in serious trouble,
[03:15]and they're getting worse. In new research presented at the annual meeting
[03:21]of the American Association for the Advancement of Science on Feb. 12,
[03:28]the marine ecologist William Cheung announced that climate change
[03:33]would have a devastating impact on the world's commercial fish
[03:38]and shellfish populations, including tuna, herring and prawns.
[03:45]Fish would flee toward the poles to escape rising temperatures,
[03:50]and many species would all but disappear from their familiar habitats.
[03:57]Many would not survive the transition Cheung estimated
[04:02]that the Atlantic cod's distribution could drop by up to 50% by 2050
[04:09]thanks to climate change.
[04:12]"The scary thing is that this isn't just happening in the future,"
[04:16]he says. "We're seeing similar things happening now."
