An Innovative Approach to Sampling Catch in the North Pacific Groundfish Fisheries

No abstracts are to be cited without prior reference to the author.

Observer sample selection and collection are subject to human and mechanical biases. Electronic monitoring (video) and automated catch sampling systems have been proposed as potential approaches for reducing these sources of bias. The National Marine Fisheries Service (NOAA Fisheries Service) partnered with the International Pacific Halibut Commission, the Marine Conservation Alliance Foundation, and the fishing industry to conduct a two-week cooperative research cruise to test technologies that may mitigate sample bias and automate sample collection. The research was conducted aboard the 70 m trawl catcher/ processor, Seafisher during the 2005 fishery for yellowfin sole (Limanda aspera) in the eastern Bering Sea. We evaluated the functionality of a prototype automatic catch sampling system based on hardware and software modifications of the vessel's motion-compensated electronic flow scale. The system was operated by entering estimated catch weight, number of desired subsamples, and desired individual subsample weights into the scale's control unit and the system's computer determined when random subsamples would be diverted from the catch and delivered by conveyor to the sample processing location. Six 100-kg subsamples were collected from each of thirty hauls and video equipment was used in a pilot study to explore the utility of using video technology to monitor for potential presorting. The system functioned as intended and automated the sample selection and collection processes to a substantial degree. Data collected during this study will also be useful for determining accuracy and precision of estimates of target and non-target species catch.