Sweden's grey seal was once terribly endangered, its population thinned almost to nothing in the 1970s from pollution and hunting in the Baltic Sea. But then the seal population began to bounce back in the 1980s. And today, in the coastal waters off Sweden, there is a pitched battle going on between the restored ranks of grey seals and the Swedish fishing industry. A new study reveals that the seals are eating as many fish as the fishing industry brings in each year, and that they're doing it in part by stealing from fishing boats and traps.
Marine biologist Karl Lundström, a researcher with Sweden's University of Gothenburg, recently published the results of a long-term study of the grey seals' diet. Like their human counterparts in Sweden, the seals are mostly eating herring, but they're also chomping on salmon and pretty much every other fish they can. They are, as Lundström put it, "fish-eating predators at the top of the marine ecosystem." And by "top," he means above humans. Though the Swedes have built fishing nets that are supposed to be humane and seal-proof, the seals turn out to be fairly ingenious at figuring out new ways to steal fish from them.
Read the description of Dr. Lundstrom's work and watch videos from io9 (Gawker Media)
Article as published in Ices Journal of Marine Science
Watch a video of a seal entering a commercial trawl at a depth of 400 meters.