Yield isopleths of the halibut, hippoglossus hippoglossus, in northern Norway
Research report
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http://hdl.handle.net/11250/114704Utgivelsesdato
1968Metadata
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1. Data on age composition, growth, and mortality rates of the halibut,
Hippoglossus hippoglossus, collected in Finmark, 1956-1960, supplemented
with data on immature halibut from various localities in
Northern Norway were examined.
2. A weight-length relationship was determined separately for males and
females.
3. Total instantaneous mortality rate was determined for males and
females based on age composition data.
2. Yield isopleths were calculated based on a knife-edged selection curve
into the fishery and also on prolonged recruitment. In the latter case
variable fishing effort was applied to the age groups to simulate the
recruitment into the fishery and withdrawal away from the fishable
stock of the large females.
5. A precise determination of maximum length or weight, natural and
fishing mortality rate were not achieved. Hence the change in yield
per recruit could only be suggested as a function of age at entry into
the fishery and fishing mortality.
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[Fiskeridirektoratets havforskningsinstitutt]Serie
Fiskeridirektoratets skrifter, Serie Havundersøkelservol 14 no 3