New Study Underscores Urgency to Rebuild Global Fisheries – EDFNewsroom
People have been catching fish for thousands of years, so you’d think by now we would have a pretty good idea of how fisheries are doing. However, the two most basic numbers that you need to answer that question – how many fish are in the sea, and how many are being caught – have been highly uncertain.
A new study published in Nature by researchers at the University of British Columbia finds that the number of fish in the sea has been underestimated, and that the world’s fisheries should be more closely monitored. We couldn’t agree more.
It’s critically important for scientists to estimate these numbers so we can tell whether catch is too high, too low, or just right. The stakes are enormous: these numbers and trends will determine what management actions are necessary to ensure that fisheries can continue to provide healthy food for billions of people and provide livelihoods for tens of millions.
Many scientists have tried to estimate the first number – how many fish are in the sea. Typically, rich streams of data are used to feed a complex model which is used to estimate it. However, the vast majority of fisheries do not collect much data, so other methods are necessary to estimate fish abundance. Scientists at the University of California at Santa Barbara and the University of Washington came up with one such method using catch statistics from the UN Food and Agriculture Organization (FAO) and information on the life history (e.g., growth rate, life span, etc) of each of the target species. Using this method, they were able to estimate the abundance (biomass) of fish species targeted by 1,793 fisheries that had not been scientifically assessed before (see their paper here).
Their conclusion: nearly 2/3 of these fisheries are too depleted to produce their maximum yields over time, meaning that the world is losing out on large amounts of yield and the jobs, profits, and economic development that come with that yield. In fact, if fishery management systems were put into place that stopped the decline in biomass and rebuilt fisheries to levels consistent with the production of maximum sustained yield, it’s possible that global catch could increase by 40% and biomass levels would go up by 56%.
For the rest of this article, go to the Environmental Defense Fund blog.
(Story and photo courtesy of EDF.)