Småsildundersøkelsene i Nord-Norge 1961/62

A progress report of the small herring investigations from September 1961 to May 1962 is presented. 1. During the autumn of 1961 rather small concentration of the 0-group were ecorded in the area around Bear Island and in the Barents Sea. Even though the herring were more abundant along the coast th...

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Bibliographic Details
Main Authors: Dragesund, Olav, Hognestad, Per T.
Format: Article in Journal/Newspaper
Language:Norwegian Bokmål
Published: Havforskningsinstituttet 1962
Subjects:
Online Access:http://hdl.handle.net/11250/113781
Description
Summary:A progress report of the small herring investigations from September 1961 to May 1962 is presented. 1. During the autumn of 1961 rather small concentration of the 0-group were ecorded in the area around Bear Island and in the Barents Sea. Even though the herring were more abundant along the coast than in the open sea, the 1961 year-class as a whole is expected to be rather poor compared with the two previous ones. Fat herring were observed in different areas at a distance of 20-100 nautic miles of the coast from Vestfjord to Varangerfjord. 2. The migration from the coastal waters into the fjords took place in late October and the herring consisted almost entirely of the 0-group. During the immigration the herring moved from warmer to colder water, the temperature decreasing inwards l-1.5°C in the surface layer. From October to February the herring were observed in the warm intermediate water layer, which usually exists in the fjords of Troms and West Finnmark during the autumn and early winter. An exception was the Porsangerfjord, where such intermediate water layer was not observed. The herring left the fjords in February-March when the warm water layer disappeared. In Porsangerfjord the herring remained in the coldest water throughout the winter and immigrated in May. 3. In six localities a total of 6150 herring were tagged with internal steel tags. (Table 1). No recaptures of the tagged fat herring have been reported nor of the 0-group tagged in Varangerfjord. The recaptures from the taggings in the Ullsfjord-Lyngenfjord and Senja areas were all taken near the tagging localities, the fishing mortality of the tagged herring being 11.30 % and 0.27 % respectively.