Browsing by Subject "Interchange"

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    Simulation testing of the sabbatical model estimator for the assessment of Southern Hemisphere humpback whale breeding Stock C and its component Sub-stocks
    (2009) Johnston, Susan J; Butterworth, Doug S; Muller, A
    Johnston and Butterworth (2009) implement four models (Resident, Sabbatical, Tourist and Migrant) to estimate parameters for the C1 and C3 substocks, including the probability of interchange between them, using a Bayesian approach which takes account of capture-recapture information from photo-id data. This estimator generally captures the underlying parameter values reasonably, though with a tendency to estimate r too low and K too high. Interchange rates are also reasonably estimated, both when the true rates are low and high. In the latter case, abundance estimates in terms are lower. Here a range of Operating Models (OMs) are defined and used to test the Sabbatical estimator
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    Open Access
    Simulation testing of two estimators for the assessment of Southern Hemisphere humpback whale breeding Stock C and its component Sub-stocks
    (2009) Johnston, Susan J; Butterworth, Doug S; Muller A
    This paper develops operating models of the C1 and C3 substocks of humpback whales in the western Indian Ocean which allow interchange between the two on the basis of the Sabbatical model for this mixing process. These operating models are used to compare the performance of the Sabbatical and Resident estimators, in what is intended as a preliminary exercise whose primary aim is to illustrate this simulation testing approach in the context of the substocks of breeding stock C of Southern Hemisphere humpback whales., .