Study Indicates Hope for Overfished Ecosystems

A UCSB-based study examining the abundance of marine fish species found that overfished ecosystems are able to recover, provided they are properly supervised.

The study, published in the July 31 issue of the journal Science, was led by Boris Worm of Dalhousie University and Ray Hilborn of the University of Washington and co-authored by Christopher Costello, an economist at the Bren School of Environmental Science & Management at UCSB. It focused on 10 large marine ecosystems and included an international team of 19 authors. Of the areas studied, several regions off the coast of the U.S., Iceland, and New Zealand are recovering from previous overfishing through careful management. “These highly managed ecosystems are improving, yet there is still a long way to go,” explained Hilborn. “Of all the fish stocks that we examined, 63 percent remained below target and still needed to be rebuilt.”

“This paper shows that our oceans are not a lost cause,” pointed out Worm, “The encouraging result is that the 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.” While this is a good sign, the authors pointed out that the paper’s analysis focused primarily on areas in developed countries where fisheries are intensively managed.

“Fisheries managers currently presiding over depleted fish stocks need to become fast followers of the successes revealed in this paper,” explained Pamela Mace, a co-author from the New Zealand Ministry of Fisheries. “We need to move much more rapidly toward rebuilding individual fish populations and restoring the ecosystems of which they are a part, if there is to be any hope for the long-term viability of fisheries and fishing communities.”