Browsing Fiskeridirektoratets skrifter, Serie Havundersøkelser (1900-1990) by Author "Ulltang, Øyvind"
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A model for incorporating changes in distribution of fishing effort in assessment of the effects of changes in trawl mesh size
Ulltang, Øyvind (Fiskeridirektoratets skrifter, Serie Havundersøkelser, Research report, 1983)Factors invalidating traditional mesh assessments are discussed with special emphasis on changes in distribution of fishing effort between areas inhabited by small and large fish. A model for studying the effects of such ... -
Stock size fluctuations and rate of exploitation of the norwegian spring spawning herring, 1950-1974
Dragesund, Olav; Ulltang, Øyvind (Fiskeridirektoratets skrifter, Serie Havundersøkelser, Research report, 1978)Stock size fluctuations and rate of exploitation of the Norwegian spring spawning herring, 1950-1974. FiskDir. Skr. Ser. HavUnders., 16: 315-337. The collapse of the Norwegian spring spawning herring stock is described, ...