A model of estimating biological attachment of fish stocks to exclusive economic zones

Abstract

The paper describes a model of calculating indices of attachment of fish stock to fisheries zones based on biological parameters. Input data are weight by age, mortality rate and the percentage area distribution of an "average" year class of the stock throughout its lifespan, The model calculates indices of biomass distribution and biomass production by area on a per recruit basis for any predetermined stage of life (age groups, spawners, etc.). Assuming that these indices of an average year class throughout its lifespan equal the sum of the respective indices of all year classes in one year, the calculated indices can be used as keys in allocating catch quotas of joint stocks to fishery zones. The model is implemented on a spread sheet (Excel) and data of the northern blue whiting stock are used as an example.