Scientists Find New Hope For Fisheries
Steps to curb overfishing are beginning to show success—at least in some areas—according to an international team of scientists whose study appears in the July 31, 2009, issue of Science. The researchers, led by Boris Worm of Dalhousie University and Ray Hilborn of the University of Washington, used what they call a “Russian doll” of layered data sets never combined before to examine current trends in the abundance of fish and the proportion of those fish caught in 10 large marine ecosystems. They ended up with some positive results.
Analyzing not just catch data, but also population assessments, trawl surveys, small-scale fishery data and modeling, the scientists found that the average proportion of fish taken had declined in five of those 10 ecosystems. Among the regions that had been particularly successful in protecting fish populations were Alaska and New Zealand, which the researchers note did not wait until drastic measures were required to conserve, restore and rebuild marine resources. Other areas where fish populations showed increased abundance included Iceland, the continental shelf of the northeast United States and the region covered by the California Current, from Canada to the Baja California peninsula, Mexico.
Most of the fisheries that showed improvement are managed by a few wealthy, industrialized nations, but some exceptions are noted. In Kenya, for example, scientists, managers and local communities have teamed up to close some key areas to fishing and restrict certain types of fishing gear. This led to an increase in the size and amount of fish available and an improvement in fishermen’s income. The authors emphasize that a combination of approaches—catch quotas and community management coupled with strategically placed fishing closures, ocean zoning, selective fishing gear and economic incentives—offers promise for restoring fisheries and ecosystems.
The authors also caution that much work remains to be done to end global overfishing. “These highly managed ecosystems are improving,” said Hilborn in a statement released by the Communication Partnership for Science and the Sea and the National Center for Ecological Analysis and Synthesis. “Yet there is still a long way to go: Of all fish stocks that we examined,63 percent remained below target and still needed to be rebuilt.”
They note that a large fraction of global fisheries are not properly managed, reported or regulated. Particularly outside wealthy industrialized nations, prospects for reducing fishing mortality are often more limited unless fishermen gain access to alternative sources of food and income. “Across all regions we are still seeing a troubling trend of increasing stock collapse,” added Worm. “But this paper shows that our oceans are not a lost cause. The encouraging result is that exploitation rate—the ultimate driver of depletion and collapse —is decreasing in half of the 10 systems we examined in detail. This means that management in those areas is setting the stage for ecological and economic recovery. It’s only a start—but it gives me hope that we have the ability to bring overfishing under control.” 
Reprinted with permission from SeaWeb’s OceanUpdate, July 2009, www.seaweb.com.
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