Countries vastly underreport catch — study

Experts have significantly underestimated the amount of fish caught over the last six decades, according to a new study that suggests the world’s fisheries should be more closely monitored.The study — published today in Nature Communications — details the results of a “catch reconstruction,” in which researchers used a variety of data to estimate the total weight of fish caught each year from the world’s oceans. It finds that countries vastly underreport their catch.In 1996, for example, the United Nations estimates that fishing catch peaked at 86 million metric tons. But today’s study asserts that the fish caught that year was closer to 130 million metric tons.

The Sea Around Us, a research initiative at the University of British Columbia, led the study. The group gets funding from the Pew Charitable Trusts and Vulcan Inc.

“The world is withdrawing from a joint bank account of fish without knowing what has been withdrawn or the remaining balance,” said Daniel Pauly, a UBC professor who is a lead author of the study, in a statement. “Better estimating the amount we’re taking out can help ensure there is enough fish to sustain us in the future.”

The authors concede that such estimates come with a high level of uncertainty. But they contend that it is a more accurate picture than the annual estimates from the United Nations’ Food and Agriculture Organization (FAO), which relies on landing data from more than 200 countries.

Countries sometimes leave out catches that are hard to track, such as discards, illegal fishing and small-scale operations, according to the study. Pauly and co-author Dirk Zeller used scientific studies, law enforcement data, local fisheries experts and hundreds of other sources to create their data set.

Their conclusion is that the world has consumed and killed far more fish than previously reported. In 2010, the most recent year in the study, the FAO estimated that 77 million metric tons of fish were caught. Pauly and Zeller say the real amount is closer to 109 million metric tons.

But that also means fishing harvests are declining at a swifter rate. The FAO estimates that catches have declined at a rate of 0.38 million metric ton per year since 1996. Today’s study asserts that rate of decline is 1.2 million tons per year.