0-group cod investigations on the Norwegian Skagerrak coast. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983

Abstract

Since 1917 0-group cod have been sampled by beach seine along the Norwegian Skagerrak coast. The average number of 0-group per haul is found to give a relatively reliable estimate of year class strenqth. There was a period of relatively low abundance in all areas from 1930 to 1950. The best period for the open areas on the south coast was from 1950 to 1970, while in more landlocked areas the abundance was highest before 1930 and after 1970. In the Langesund area and inner parts of the Oslofjord there has been a general decline since 1950, at least partly caused by environmental changes due to pollution.