BIO 360  Ecology

Lecture 17:  Sustainable Management of Fisheries

I.  History of fisheries management
    A.  Exploitation of fishery followed by fairly rapid collapse

    B.  Why don't humans manage fisheries sustainably?

    C.  Tragedy of the Commons (Hardin 1968)

        1.  Resource available on first-come, first-serve basis, so makes sense (at individual level) to maximize harvest now
        2.  Aggregate effect of rational behavior by individuals can lead to irrational action by the community

II.  Use of population growth models to predict maximum sustainable yield (MSY)

    A.  Maximum Sustainable Yield: the maximum number of fish that can be harvested in perpetuity

    B.  Assumptions
        1.  Fish populations grow according to logistic model
        2.  If the catch rate is less than the fish population growth rate, the fishery is sustainable

    B.  Graphical estimation of the Maximum Sustainable Yield


III.  Policy approaches to management
    A.  Fixed quota

    B.   Fixed effort

IV.  Overfishing affects not just the fishery of interest, but also aquatic communities and ecosystems

     -  In marine environments, overexploitation tends to remove top predators