Results 1 to 10 of about 200 (102)
Important marine areas for endangered African penguins before and after the crucial stage of moulting [PDF]
Scientific Reports, 2022 The population of the Endangered African penguin Spheniscus demersus has decreased by > 65% in the last 20 years. A major driver of this decrease has been the reduced availability of their principal prey, sardine Sardinops sagax and anchovy Engraulis ...
Tegan Carpenter-Kling +9 more
doaj +2 more sources
Assessing the South African sardine resource: two stocks rather than one? [PDF]
African Journal of Marine Science, 2015 Sardine Sardinops sagax distributed off the west and south coasts of South Africa have traditionally been assumed to comprise a single well-mixed stock for assessment and management purposes. New research, however, lends weight to the possibility of two stocks in this region.
Carryn L De Moor
exaly +5 more sources
Alternative risk thresholds for South African sardine and anchovy resources
, 2021 This document considers alternative biomass-related risk thresholds for use in tuning Candidate Management Procedures for the South African sardine and anchovy resources. The document is written to provide background information to the key question to the panel “How do we best choose risk thresholds in terms of biomass levels for sardine and anchovy”?
openaire +1 more source
Updated assessment of the South African sardine resource using data from 1984‐2022
, 2023 A quantitative assessment of the South African sardine resource has been updated to include data from 1984 to 2022, based on the previous stock structure hypothesis which assumes two components (‘west’ and ‘south’), separated at Cape Agulhas, but with some mixing. This model assumes no stock recruitment relationship during conditioning.
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Baseline assessment of the South African sardine resource using data from 1984‐2019
, 2021 A quantitative assessment of the South African sardine resource has been updated to include data from 1984 to 2019. This twomixing‐component hypothesis assumes no stock recruitment relationship during conditioning. The west component abundanceremains at a very low level.
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, 2022 The assessment of the South African sardine resource is in the process of being revised and updated using data available up to November 2015. Two primary hypotheses regarding the sardine stock structure have been agreed for investigation. The first considers sardine distributed off the west and south coasts of South Africa to form a single stock or ...
de Moor, Carryn, Butterworth, Doug
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Updated assessment of the South African sardine resource using data from 1984‐2020
, 2021 A quantitative assessment of the South African sardine resource has been updated to include data from 1984 to 2020. This two mixing‐component hypothesis assumes no stock recruitment relationship during conditioning. The west component abundance remains at a low level, but the spawner biomass is estimated to be higher than that estimated a year ago ...
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, 2021 A sensitivity test to the quantitative assessment of the South African sardine resource has been carried out, in which the survey estimate of sardine abundance west of Cape Agulhas was replaced with a ‘combined’ estimate taking into account a regression between the ratio of sardine bycatch with round herring fishing and round herring catches with the ...
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A Progress Report on the Revision to the Operating Model for the South African Sardine Resource
The operating model for South African sardine resource is being revised and updated following recommendations from the MARAM International Stock Assessment Workshop in Cape Town, December 2011 (Anon. 2011). This document provides a brief description of changes to the model since de Moor and Butterworth (2011) and gives some initial results.
de Moor, Carryn, Butterworth, Doug
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, 2023 This document provides initial results from fitting the model of South African sardine proposed by de Moor (2023) to available data disaggregated by two areas, west and east of Cape Agulhas. These results correspond to the two component option, with cold temperate sardine spawning off the west coast and warm temperate sardine spawning off the west and ...
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