September 3, 2014 — One of the inherent difficulties in fishing is bycatch, when unwanted or protected species are swept up in nets. To counter this, fishermen may sail to different waters or use devices called excluders to let specific types of fish and marine life escape. KDLG’s Chase Cavanaugh has more on a device that would reduce certain bycatch in the Bering Sea.
Earlier this year, the North Pacific Research Board held its annual Alaska Marine Science Symposium. The event featured research on many different topics, including bycatch. This is the term for unwanted or protected species that are swept up along with a fisherman’s regular catch. Areas such as the Bering Sea have hard limits on the amount of bycatch fishermen may collect, and if they reach the limit, they can’t continue fishing there.
Enter John Gauvin, the Fisheries Science Director of the Alaska Seafood Cooperative. He delivered a keynote address at the Symposium about his work on excluders, devices fitted to a net that let certain animals escape, while keeping target species trapped. Gauvin’s work centered on testing designs that would catch pollock in the Bering Sea while allowing king salmon to escape. He says an accurate test requires being able to count both types of fish.
“We came up with a secondary net to append to the trawl that’s flown on water kites, and this allows us to retain what effectively is supposed to be escapement. We can look at the number of salmon and pollock that are retained in this secondary net compared to the amount in a haul of pollock and salmon that we count and weigh.”