Fishing Fleets Increase Power, But Fish Are Harder to Catch
A new paper from the Sea Around Us Project, published online on June 19 in the journal Fish and Fisheries, maps global fishing effort patterns over time and describes how those patterns relate to the amount of catch. The authors calculated trends in catch per unit of effort (CPUE) by combining data on power use (in watts) by fishing vessels with previously published data on catch. The study reveals that fishing ﬂeets increased their effort—as measured by engine power expended—by ten-fold on average since the 1950s. Similarly, the range of fleets has increased to include the entire globe. While the global catch rate initially increased with expended effort, it stalled in the 1980s and has been slowly declining since then. Analysis of CPUE indicates that it now takes twice as much effort to catch a fish as it did 50 years ago, which likely indicates a reduction in the amount of fish still in the water.