After decades of declines, most of the world’s fish populations could recover in just ten years while fishermen make more money at the same time, scientists reported in a new study. The solution is for more countries to adopt systems for sharing rights to harvesting fish, which have been effective in a handful of countries, including the U.S. and Belize. By 2050, global fish populations could double if all countries switched to the best management practices. The percentage of fisheries that are considered biologically healthy would grow from around 47 percent today to 77 percent in 10 years.