Satellites see industrial fishing’s footprint on the high seas

Scientists tag sharks to see where they roam in the high seas, but until now they couldn’t track the seas’ biggest eater: Humans.

By using ships’ own emergency beacons, researchers got the first comprehensive snapshot of industrial fishing’s impacts around the globe. And it’s huge — bigger than scientists thought, according to a new study.

Large-scale commercial fishing covers more than 55 per cent of the oceans, with the world’s fishing fleet travelling more than 460 million kilometres a year — three times the distance between Earth and the sun, according to research in Thursday’s journal Science.

Five countries — China, Spain, Taiwan, Japan and South Korea — were responsible for 85 per cent of high-seas fishing.

“The most mind-blowing thing is just how global an enterprise this is,” said study co-author Boris Worm, a marine biologist at Dalhousie University in Halifax. “It’s more like factories that are massproducing product for a global market and less like hunters that are stalking individual prey.”

The fishing patterns were gleaned from 22 billion automated ship safety signals beamed to satellites. Before this, scientists had to rely on a sampling of ships’ logs and observations, which were spotty.

Researchers said these findings could be used to better protect the oceans and keep fisheries alive.

“For too long we haven’t recognized that human impacts are the largest impacts on the planet,” Block said. “We have to come up with a better [monitoring] system or else we’ll end up with a planet devoid of bluefin tuna, certain sharks.”