Size-Selective Harvesting and Age-At-Maturity II: Real Populations and Management Options

  • T. K. Stokes
  • S. P. Elythe
Part of the Lecture Notes in Biomathematics book series (LNBM, volume 99)

Abstract

Parameters for a simple stage-structured harvesting model are derived for five North Sea demersal fish stocks. The parameters are used to generate contour plots of fitness and yield on axes of size-at-maturity Vs size-at-first-capture, and age-at-maturity Vs age-at-first-capture. Such graphs are used qualitatively to assess possible changes in the exploited populations that might result from management actions such as altering mesh size (and hence size-at-capture) and/or harvesting rate.

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Copyright information

© British Crown Copyright 1993

Authors and Affiliations

  • T. K. Stokes
    • 1
  • S. P. Elythe
    • 2
  1. 1.Fisheries LaboratoryMAFFLowestoftUK
  2. 2.Department of Statistics and Modelling ScienceUniversity of StrathclydeGlasgowUK

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