A comparison between industry and observer catch compositions within the Gulf of Alaska rockfish fishery

Faunce, C. H. A 2011. comparison between industry and observer catch compositions within the Gulf of Alaska rockfish fishery. – ICES Journal of Marine Science, 68: 1769–1777. Stock assessment scientists and fishery managers operate under the necessary assumption that the identities of species in official catch reports are known without error. To test this assumption, the incidence, magnitude, and possible causes of species misidentification between industry and fishery-observer data sources were investigated for 29 rockfish landings made in Kodiak, AK. Rockfish species were misidentified in nearly all these landings, and the incidence of misidentification between data sources differed among species rather than the processing plant examined. Although observers failed to identify species recorded by processing plant staff as a result of small sampling fractions, the industry missed species that were identified by observers in more than half the offloads examined. The presence of management species complexes did not reduce the likelihood of erroneous quota debiting as a result of species misidentification. In one landing, the misidentification of the main rockfish species corresponded to the release of a weekly report on total allowable catch and resulted in a delayed fishery closure. Efforts to improve the accuracy of species identifications reported by industry in landing reports are warranted in Alaska, and methods to accomplish this through efficient deployment of observers are discussed.