January 19, 2017 — China, the world’s largest seafood producer, has done something extraordinary. For the past 20 years, despite minimal management and some of the most intense industrial fishing in the world, it has maintained large catches of key species in its most productive waters.
That same kind of intense, lightly managed industrial fishing has collapsed other fisheries, such as Newfoundland’s cod fishery in the 1990s. China’s ability to sustain its catches has puzzled scientists, some of whom have even questioned the accuracy of the country’s catch reports.
A new study from UC Santa Barbara, published in the Proceedings of the National Academy of Sciences, suggests another explanation: By reducing the population of predatory fish, China has increased populations of preyed-upon species.
“If you fish down the large predatory fish, then you can catch more small prey fish, because they are no longer being eaten before you get to them,” explained lead author Cody Szuwalski, a fisheries scientist in UCSB’s Sustainable Fisheries Group. The group is a collaboration of the campus’s Marine Science Institute and Bren School of Environmental Science & Management.