Årsyngel av brisling i fjordene på Vestlandet og i Trøndelag høsten 1975

Abstract

Prognoses for catch of sprat in 1976 in different fjords of western Norway are presented. The prognoses are based on indices of abundance of 0-group sprat calculated from echo recordings obtained on a survey in October-November 1975 by R. V. "Johan Hjort". The echo signals are processed by a computer system, and a relative measure of sprat density per distance travelled, combined with the area of each fjord, provides the abundance index. This index reflects the abundance of sprat available to the fishery 6 -8 months later.