Abstract

Since 1978, the annual incidental take of Dall’s porpoises by the Japanese salmon land-based and mothership fisheries has been reported to the International North Pacific Fisheries Commission by the Japan Fisheries Agency. Since 1981, three observers per mothership fleet have monitored the incidental take of Dall’s porpoises by the Japanese salmon mothership fishery. Estimates of the annual total incidental take based on observer data are presented and compared to reported values. There was a significant difference between the incidental take rates in 1981 compared to 1982 and between observed and reported values for the incidental take. In the period 1978-1982, eleven harbor porpoises were returned by the catcherboats for examination.