FISHERIES_2020_JUL_SWG-PEL_51.pdf (531.73 kB)

The South African anchovy assessment with annual maturity ogives

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posted on 03.02.2021, 04:09 by Carryn de MoorCarryn de Moor
The assessment of South African anchovy has been updated to include time varying annual maturity ogives, in addition to the recent inclusion of an informative prior distribution on the hydro‐acoustic survey bias. The model continues to assume a Beverton Holt stock recruitment relationship, time‐invariant natural mortality of 1.2year‐1 and that the Daily Egg Production Method indices of abundance provide absolute estimates of anchovy spawner biomass. This updated assessment estimates the resource abundance to be almost two thirds of the historical (1984‐2019) average, with a total biomass of 1.5 million tons, in November 2019.

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Department of Mathematics and Applied Mathematics, University of Cape Town