In the last decade, studies analyzing global fisheries statistics since 1950 have shown a decline in marine fish catches. Most experts believe that the decline in catches is due to overexploitation, that is, we have removed fish out of the sea faster than they can replenish. Projections of trends since 1950 suggest a continued depletion of fish and consequent collapse of fisheries.
However, a handful of fisheries scientists have argued recently that these studies exaggerate the problem and that most fish stocks are actually stable or rebounding (see recent blog in New York Times). Their message is that the world is mostly fine and that no significant action is required to turn things around. Based on existing evidence, most marine biologists believe that they are wrong. Most fishermen around the world will also agree that we have a real problem.
Why are the skeptics wrong? Mainly because they are showing new ‘global’ trends that suggest stability by using only data from a subset of the world’s fisheries – mostly those that are well managed and monitored, and which are doing better than most other fisheries. I agree that well managed fisheries can rebound, but these represent less than a tenth of the world’s fisheries. Who would agree on the results of a study describing the wealth of Americans using only Forbes’ millionaires list?