Back in 2006, the Canadian marine biologist Boris Worm authored a controversial study that warned that we could literally run out of fish by 2048.Since then some new conservation measures were been put in place in a few ecosystems. And it turns out they've worked. A new, more detailed study by Worm and a collaborator named Ray Hilborn shows that fish are bouncing back in a number of places:Fish abundance is increasing in previously overfished areas around Iceland, the north-east U.S. shelf, the Newfoundland-Labrador shelf and California. This has benefitted species such as American plaice, pollock, haddock and Atlantic cod.According to the authors "some of the most spectacular rebuilding efforts have involved bold experimentation with closed areas, gear and effort restrictions and new approaches to catch allocations and enforcement."So the good news is that when an area tries to manage fisheries, it works. The problem, though, is that this kind of fisheries management isn't happening everywhere. And where it isn't happening-Ireland and the North Sea, for example-we're still in danger of totally destroying ecosystems.