The secret to preventing fishery decline: stop fishing so much
The concept of restoring ecosystems damaged by human exploitation has always interested me, so the recent edition of *Science* featuring Restoration Ecology sent my heart into a pitter-patter. There are a number of good news stories and perspectives in it, but the primary research article on “Rebuilding Global Fisheries” in particular deserves a few words.
Global fish stocks have been declining precipitously since the industrialization of the fishing fleet, especially since the 1950s when technology, globalization, and improved shipbuilding proved too much for many popular (and some previously unpopular) fish stocks. Overfishing has resulted in a sharp decline in overall fish biomass, but has been especially hard on larger, longer-lived fish. Not only are there fewer fish in the seas, the ones that remain are on average 22% smaller today than 50 years ago. We are basically eating our way down the food chain, destroying the largest species and then moving on to smaller ones that the larger ones originally ate. Where we once caught large schools of giant fish on the open ocean (tuna), many people now munch on shockingly unattractive, bottom-feeding fish that have been given pretty but inaccurate names (Chilean sea bass). A sordid affair.
The article is about restoring ecosystems, and thankfully there is some positive news to report. There are a range of policy and technology options that could help bring fish stocks back to what is known as Multispecies Maximum Sustainable Yield: reducing the total allowable catch, imposing gear restrictions to avoid by-catch, creating marine preserves that are off-limits to fishing entirely, and buying out excess fishing capacity to reduce overall pressure on ecosystems, among others. The authors are clear that none of these work all the time, and rarely do any of these options succeed by themselves. In fact, these implementations require “that good local governance, enforcement, and compliance form the very basis for conservation and rebuilding efforts.” That seems like a self-evident statement, but across the world a lack of adequate government means a failure to curb and control overfishing.
Lack of government is not just a problem for Somalia, either. As the authors point out, “in the United States, where 67 overfished stocks have rebuilding plans, 45% of those were still being overfished in 2006, whereas only 3 stocks had been rebuilt at that time.” The sad truth is that there will be economic costs to reduced fishing in the short term; we can expect job losses in the fishing industry and fewer sales until stocks recover. The good news is that the ocean is a miraculously productive place. Its sheer enormity underlies its ability to provide food and well-being for hundreds of millions of people across the globe. With strong protections, the ocean’s bounty can be a vital and sustainable source of nutrition and pleasure for future generations.