Results from Tagging Experiments on a Spawning Stock of Petrale Sole, Eopsetta jordani (Lockington)

Abstract

A review is made of the historical development of the petrale sole (Eopsetta jordani) fishery off the State of Washington (U.S.A.) and British Columbia (Canada), with statistical records of catches. A shift in recent years in the depth of trawl fishing from shallow water over the continental shelf to deeper water on the continental slope resulted in the discovery of dense concentrations of petrale sole at depths from 170–250 fathoms off the west coast of Vancouver Island. Tagging was carried out in the early spring of 1954 and 1955 on these deep-water stocks. Recoveries to May 30, 1956, from some 3,800 tags released showed that the male segment of the stock moved north and inshore along the Vancouver Island coast after spawning and at least part of the stock moved eventually into Hecate Strait, British Columbia. The tagged population contributed mainly to the fisheries adjacent to the northwest coast of Vancouver Island and in the Queen Charlotte Sound area. Subsequent recoveries from the Esteban Deep during the spawning seasons of 1955 and 1956 and the absence of the stock on this ground at other seasons, strongly suggest a homing tendency for this species. A discussion is given of the possible directive factors in the spawning migration. However, at the present time the actual factors involved remain unknown.