Vintersildundersøkelser i 1973

Abstract

There was also in 1973 a total ban on fishing for adult Norwegian spring spawning herring. In order to trace the distribution and migration of winter herring two commercial fishing boats equipped with purse seine, drift and sct nets were chartered by the Directorate of Fisheries. The investigations were conducted by the Institute of Marine Research, and representatives of the Institute acted as cruiseleaders onboard the vessels. The fishing boats were allowed to fish for biological sampling according to instructions given by the Directorate of Fisheries. The investigations commenced in middle of January and continued throughout the winter until the end of March. Only small concentrations of herring were recorded along the coast of Norway from Stad to Lofoten. Spawning was located in restricted areas off Møre and Trøndelag. Off northern Norway herring were recorded in January at Tromsøflaket, and later in the winter these herring moved southwards along the coast and spawned off Lofoten—Vesterålen. The investigations indicated that the spawning stock size was at very low level, but the stock was slightly more abundant than in 1972. Between 85 and 90% of the herring consisted of the 1969 year class of which most were fast growing fish of the southern growth type.