Enter the super predator.
The result of a decade of work, new research shows that the typical marine fishery kills adult fish at 14 times the typical rate of a wild predator. Humans tend to hit fisheries harder—with hands, hooks, and nets—than any other group of wild animals.
Even the better managed fisheries often start with the proposition of harvesting as much as possible. “That’s the general paradigm,” says Chris Darimont, a Hakai Institute-Raincoast Conservation Society scholar at the University of Victoria. “How can we maximize the so called sustainable yield to humanity?”
Drawing on existing data, Darimont compared the predation rates of human versus wild predators. For example, in Alaska’s Kodiak Archipelago, grizzly bears catch six percent of the adult salmon, while humans catch 78 percent, or 13 times more fish. Given the numbers, he says, humanity’s toll on ocean species is alarming and underlies many of the problems observed in the oceans today.
“Everyone assumes we are this dominant predator, but until now we didn’t know how to describe it,” he says. “Those cross-ecosystem comparisons had never been done before. It provides details at a global scale.” (Darimont’s research is supported by a grant from the Tula Foundation, which also funds Hakai Magazine. The magazine is editorially independent of the institute and foundation.)
Mechanized fishing methods, global seafood markets, and industrial processing—combined with relatively high reproduction rates among fish and their schooling behavior—may help to explain the high take in fisheries, says Darimont.