Browsing by Subject "Hake Assessment"

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    Conditioning of some robustness tests for the new reference case hake assessment
    (2009) Rademeyer, Rebecca A; Butterworth, Doug S
    Results are presented for a number of sensitivity tests to the New Reference Case hake assessment. The broad feature of these results is that while the current depletion of the M. paradoxus population is quite robustly determined, that for M. capensis is less certain.
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    Do alternative assumptions for the baseline hake assessment lead to substantial changes in results
    (2008) Rademeyer, Rebecca A; Butterworth, Doug S
    Results are presented for a series of sensitivities to the new baseline assessment (NBA) for the South African hake resource (Rademeyer and Butterworth, 2008). The selection of these sensitivities follows in part from issues/concerns in the assessment used for the last OMP that need further consideration in specifying Operating Models (OMs) for the next OMP revision. These include the use of catch-at-length (CAL) information for years where age-length keys (ALKs) are not available, perceptions of the relative status of the two species, the appropriateness of the survey-based algorithm to split the offshore trawl catches by species and the values of the survey constant of proportionality (from swept area estimate to total biomass in absoluter terms).