Stock abundance on the rise

UW led study concludes fisheries abundance is increasing in many places

Results of a newly released project led by the University of Washington says that thanks to effective management nearly half of the fish caught worldwide are at sustainable levels or successfully rebuilding.

“Fish stocks are not all declining around the world,” said Ray Hilborn, lead author of the study and a professor at the UW School of Aquatic and Fishery Sciences. “They are increasing in many places, and we already know how to solve problems through effective fisheries management.”

A report on the project, which builds on a decade-long international collaboration of researchers, was published on Jan. 13 in Proceedings of the National Academy of Sciences.

Data collected for the project is helping scientists and fisheries managers to identify where overfishing is occurring, as well as areas that could support ore fishing. The database now includes information on nearly half of the world’s fish harvest, up from about 20 percent represented by the last compilation in 2009.

Researchers acknowledged that most fish stocks in South Asia and Southeast Asia still do not have scientific estimates of health and status available. Fisheries in India, Indonesia and China alone represent 30 percent to 40 percent of the world’s fish harvest that is essentially unassessed, they said.

“Given that most countries are trying to provide long-term sustainable yield of their fisheries, we want to know where we are overfishing, and where there is potential for more yield in places we’re not fully exploiting,” Hilborn said.

Co-author Ana Parma, of Argentina’s National Scientific and Technical Research Council, noted that there are still big gaps in the data, because the data on smaller fisheries is ore scattered has not been standardized ad is harder to collate or because these fisheries are not monitored on a regular basis.

Co-author Christopher Costello, of the University of California Santa Barbara said the assembled data allowed them to test whether fisheries management allows stocks to recover.

“We found that, emphatically, the answer is yes,” he said.

“There isn’t really a one-size-fits-all management approach,” Costello said. “We need to design the way we manage fisheries so that fishermen around the world have a long-term stake in the health of the ocean.”

Participating co-authors of the project also were from the University of Victoria, University of Cape Town, National Institute of Fisheries Research (Morocco), Rutgers University, Seikai National Fisheries Research Institute Japan, CSIRO Oceans and Atmosphere, Fisheries New Zealand, Wildlife Conservation Society, Marine and Freshwater Research Center (Argentina), European Commission, Galway-Mayo Institute of Technology, Center for the Study of Marine Systems, Sustainable Fisheries Partnership, The Nature Conservancy, and the United Nations Food and Agriculture Organization.

Their work was presented recently in Rome by Hilborn and others during the FAO’s International Symposium on Fisheries Sustainability.