Population Studies on Juvenile Herring in Barkley Sound, British Columbia

Abstract

Population studies were carried out on herring in the juvenile (first year, post-metamorphosis) stage in Barkley Sound in the summers of 1951 to 1954. Their chief objective was to detect and estimate yearly changes in relative abundance. The juveniles were found mostly in shallow, sheltered bays, inlets and channels, mainly on the southeast side of the sound. The stocks apparently arose from different mixtures of the progeny of a series of spawnings extending over two months and located mainly on the northwest side of the sound. Mixing between localities averaged less than one-third. The 1953 and 1954 juvenile populations were above average (both about 640 million fish), while the 1952 population was below average. Upon recruitment to the fishery, the relative strength of these three year-classes was comparable to that observed in the juvenile stage. Thus, surveys of herring abundance at the juvenile stage provide an index of year-class strength at recruitment.