Improving Trawl Selectivity in the Pacific Hake Fishery

This study examined two versions of an open escape window bycatch reduction device (BRD) designed to reduce Chinook salmon (Oncorhynchus tshawytscha) and rockfish (Sebastes spp.) bycatch in the U.S. west coast Pacific hake (Merluccius productus) fishery. Tests were conducted off central Oregon during 2009 and 2010 aboard a midwater trawling fishing vessel. Fish behavior and gear performance were observed using autonomous high-resolution low-light color video camera systems. During this study, bycatch of Chinook salmon, widow rockfish (S. entomelas), and canary rockfish (S. pinniger) was reduced by as much as 81.8%, 26.7%, and 14.7%, respectively. Chinook salmon and widow rockfish escapement rates were affected by the number and location of escape windows. The presence of artificial light was also noted to influence which escape window Chinook salmon utilized when escaping. Between the two designs examined, the mean escape time of Chinook salmon differed significantly. Minimal escapement of Pacific hake was observed. Results indicate that Chinook salmon and rockfish bycatch can be reduced in the Pacific hake fishery using an open escape window BRD.