Strathprints Home | Open Access | Browse | Search | User area | Copyright | Help | Library Home | SUPrimo

Ecosystem limits to food web fluxes and fisheries yields in the North Sea simulated with an end-to-end food web model

Heath, Michael (2012) Ecosystem limits to food web fluxes and fisheries yields in the North Sea simulated with an end-to-end food web model. Progress in Oceanography, 102. pp. 42-66. ISSN 0079-6611

[img] PDF (Author final version of accepted article) - Submitted Version
Available under License ["licenses_description_unspecified" not defined].

Download (612Kb)
    [img] PDF (Online supplementary file to accompany published manuscript) - Submitted Version
    Available under License ["licenses_description_unspecified" not defined].

    Download (647Kb)

      Abstract

      Equilibrium yields from an exploited fish stock represent the surplus production remaining after accounting for losses due to predation. However, most estimates of maximum sustainable yield, upon which fisheries management targets are partly based, assume that productivity and predation rates are constant in time or at least stationary. This means that there is no recognition of the potential for interaction between different fishing sectors. Here, an end-to-end ecosystem model is developed to explore the possible scale and mechanisms of interactions between pelagic and demersal fishing in the North Sea. The model simulates fluxes of nitrogen between detritus, inorganic nutrient and guilds of taxa spanning phytoplankton to mammals. The structure strikes a balance between graininess in space, taxonomy and demography, and the need to constrain the parameter-count sufficiently to enable automatic parameter optimization. Simulated annealing is used to locate the maximum likelihood parameter set, given the model structure and a suite of observations of annual rates of production and fluxes between guilds. Simulations of the impact of fishery harvesting rates showed that equilibrium yields of pelagic and demersal fish were strongly interrelated due to a variety of top-down and bottom-up food web interactions. The results clearly show that management goals based on simultaneously achieving maximum sustainable biomass yields from all commercial fish stocks is simply unattainable. Trade-offs between, for example, pelagic and demersal fishery sectors and other properties of the ecosystem have to be considered in devising an overall harvesting strategy.

      Item type: Article
      ID code: 38179
      Notes: References and page numbers entered
      Keywords: ecosystems, fisheries, mathematical analysis, potential yield, nutrient cycles, plankton, benthos, Probabilities. Mathematical statistics, Aquatic Science, Geology
      Subjects: Science > Mathematics > Probabilities. Mathematical statistics
      Department: Faculty of Science > Mathematics and Statistics
      Related URLs:
        Depositing user: Pure Administrator
        Date Deposited: 06 Mar 2012 12:15
        Last modified: 14 Jul 2014 03:57
        URI: http://strathprints.strath.ac.uk/id/eprint/38179

        Actions (login required)

        View Item

        Fulltext Downloads: