Story modified from the original press release issued by the University of Washington

Nearly half of the fish caught worldwide are from stocks that are scientifically monitored and, on average, these stocks are increasing in abundance. According to a new global analysis, effective management appears to be the main reason these stocks are at sustainable levels or rebuilding successfully.

The analysis, which incorporated fisheries data from around the world, was conducted by an international research team supported by the Science for Nature and People Partnership. Their results were published January 13th in the Proceedings of the National Academy of Sciences.

The results show that fisheries management works when applied, and the solution for sustaining fisheries around the world is implementing effective fisheries management, the authors explained.

"There is a narrative that fish stocks are declining around the world, that fisheries management is failing and we need new solutions — and it’s totally wrong," said lead author Ray Hilborn, a professor in the University of Washington School of Aquatic and Fishery Sciences. "Fish stocks are increasing in many places, and we already know how to solve problems through effective fisheries management."

The project builds on a decade-long international collaboration to assemble estimates of the status of fish stocks — or distinct populations of fish — around the world, from Peru to the Mediterranean, and to Japan. This information helps scientists and managers know where overfishing is occurring or where some areas could support even more fishing.

The team's database includes information on nearly half of the world's fish catch, or about 880 fish stocks, providing perhaps the most comprehensive picture worldwide of the health and status of fish populations.

"The key is we want to know how well we are doing, where we need to improve, and what the problems are," Hilborn said.

By pairing information about fish stocks with recently published data on fisheries management activities in about 30 countries, the researchers found that more intense management led to healthy or improving fish stocks, while little to no management led to overfishing and poor stock status.

"With these data, we could test whether fisheries management allows stocks to recover. We found that, emphatically, the answer is yes," said co-author Christopher Costello, a professor of environmental and resource economics at University of California, Santa Barbara, and a board member with Environmental Defense Fund. "This gives credibility to the fishery managers and governments around the world that are willing to take strong actions."

To be successful, management should be tailored to fit the characteristics of the different fisheries and the needs of specific countries and regions. The main goal should be to reduce the total fishing pressure when it is too high, and find ways to incentivize fishing fleets to value healthy fish stocks.

"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."

Still, there are data-deficient areas of the world. Scientific estimates of the status of most fish stocks in South Asia and Southeast Asia are not available, and fisheries in India, Indonesia and China alone represent 30% to 40% of the world's fish catch that is essentially unassessed.

"There are still big gaps in the data and these gaps are more difficult to fill," said co-author Ana Parma, a principal scientist at Argentina's National Scientific and Technical Research Council and a member of The Nature Conservancy global board. "This is because the available information on smaller fisheries is more scattered, has not been standardized and is harder to collate, or because fisheries in many regions are not regularly monitored."