FISHERIES 2021 JUN SWG WCRL11 2021 Updated combined Poaching trends.pdf (422.85 kB)

Compliance poaching trends updated up to 2020 for West Coast rock lobster from modelling the “old” and the “new” databases simultaneously

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Updated results are given for an approach which simultaneously models the “old” and the “new” databases as recommended by the Panel for the 2018 International Fisheries Stock Assessment Workshop, with poaching data for 2020 now included. These results are compared to those obtained previously. For case where the “old” database is upweighted (as has been the accepted recent practice), the 2020 poaching index estimated for the southern Super-area 8+ shows a statistically significant increase compared to 2019 and is also the highest estimated value over the whole time series. In the case of the northern Super-areas (3-7) a statistically significant decrease is evident. A three-point smoothing approach adopted previously is used for converting the poaching series obtained into the outputs to be used for the input series to the assessments.

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Department of Mathematics and Applied Mathematics, University of Cape Town