Spawning area and distribution of 0-group cod, Gadus morhua L., on the Møre coast. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983

Abstract

This paper deals with the location of some major spawning grounds for cod, Gadus morhua L., on the Møre coast. The density distribution of adults prior to spawning and the 0-group fish later on was recorded. The two parts of the investigation were carried out in March-April and August respectively in 1981-1983. The prespawning distribution was recorded using acoustic techniques and abundance estimates were given. Based on these results spawning grounds were proposed. To give precise borders of the spawning grounds a plankton collector, the Juday net, was used to estimate the density distribution of cod eggs. The 0-group were sampled whilst in the process of settling to the bottom. Its distribution was obtained using a pelagic trawl for the free-swimming specimens and a beach seine for the bottom settled ones. The results limited the major spawning to the southern part of the investigated area. Main spawning grounds were Borgund Fjord, Goksøyr Bay, Fåhvær Channel and Bremanger Bay. Local spawning areas were recorded in 1983. Abundance estimates suggest that between 6 and 11 million specimens were present in the area during the investigation in winter 1982 and 1983. The fish abundance was significantly more southerly in the later part of the spawning periods. The investigation on 0-group cod indicates that nursery areas on the Møre coast are limited to the shallower and less exposed locations. The highest concentrations of 0-group cod were found in the shallow fjords around the island of Smøla and in Borgund Fjord.