Fishery managers too often develop fishing rules expecting that the same species will be found in roughly the same place every year. Setting catch limits for fishing requires some assumptions – and until recently, one of them has been that the vast ocean, while subject to cycles, is basically stable over time. But new information challenges that notion, as scientists and some policymakers have grown increasingly aware of long-term shifts in the ocean environment… “It occurred to us that there was another story in there,” said Rutgers University scientist Dr. Malin Pinsky. “By looking at data that already existed from a new and different angle, we could pinpoint where fish populations were found – and if those locations changed over time.”… Fish, even of the same species, can spread across a large geographic range, but scientists can calculate where most of the population is concentrated – the geographic centerpoint. By comparing the location and depth of the trawl to the centerpoint of the population, Pinsky’s analysis shows how different fish populations have shifted over time.