Length-based assessment of five small pelagic fishes in the Senegalese artisanal fisheries.

Fisheries management is an important strategy for ensuring sustainable use of resources. However, in West Africa, in the absence of quality data for many stocks and effective stock assessment models, the cases where this has been truly successful are notable for their rarity. In West Africa, small p...

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Main Authors: Bocar Sabaly Baldé, Patrice Brehmer, Penda Diop Diaw
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2022-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0279768
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author Bocar Sabaly Baldé
Patrice Brehmer
Penda Diop Diaw
author_facet Bocar Sabaly Baldé
Patrice Brehmer
Penda Diop Diaw
author_sort Bocar Sabaly Baldé
collection DOAJ
description Fisheries management is an important strategy for ensuring sustainable use of resources. However, in West Africa, in the absence of quality data for many stocks and effective stock assessment models, the cases where this has been truly successful are notable for their rarity. In West Africa, small pelagic fish are of great socio-economic importance, as well as good indicators of fish stressors. Here, historical data (2004-2019) of five small pelagic species (Sardina pilchardus, Ethmalosa fimbriata, Trachurus trecae, Scomber colias and Mugil cephalus) were collected in Senegalese waters. The B/BMSY results showed stocks to be collapsed (B/BMSY = 0.13 and 0.1 for M. cephalus and S. pilchardus, respectively) and heavily overfished (B/BMSY = 0.24; E. fimbriata). Only S. colias and T. trecae stock were considered to be in good condition (B/BMSY = 1.7 and 1.4 respectively). The Lc/Lc_opt ratio was ≤ 1 for E. fimbriata and M. cephalus, suggesting that the individuals caught for these species were too small. To reverse these bad stock statuses, catching individuals at Lc_opt, 25, 21, 43 and 18 cm for S. colias, E. fimbriata, M. cephalus and S. pilchardus, respectively should be a natural guarantee against recruitment failure and allow individuals to ensure the long-term survival of populations, in a context of data poor fisheries. In conclusion, this study shows that, despite limitations, the LBB model can provides indicators of stock status for species to encourage management measures, especially in data poor countries. It is hoped that these results can help to better assess many stocks currently considered too data poor to be assessed or at least encourage data collection effort on stocks discerned as in bad or critical status.
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spelling doaj.art-97050aec847e40cdbd2fc2104d6c64da2023-01-25T05:32:44ZengPublic Library of Science (PLoS)PLoS ONE1932-62032022-01-011712e027976810.1371/journal.pone.0279768Length-based assessment of five small pelagic fishes in the Senegalese artisanal fisheries.Bocar Sabaly BaldéPatrice BrehmerPenda Diop DiawFisheries management is an important strategy for ensuring sustainable use of resources. However, in West Africa, in the absence of quality data for many stocks and effective stock assessment models, the cases where this has been truly successful are notable for their rarity. In West Africa, small pelagic fish are of great socio-economic importance, as well as good indicators of fish stressors. Here, historical data (2004-2019) of five small pelagic species (Sardina pilchardus, Ethmalosa fimbriata, Trachurus trecae, Scomber colias and Mugil cephalus) were collected in Senegalese waters. The B/BMSY results showed stocks to be collapsed (B/BMSY = 0.13 and 0.1 for M. cephalus and S. pilchardus, respectively) and heavily overfished (B/BMSY = 0.24; E. fimbriata). Only S. colias and T. trecae stock were considered to be in good condition (B/BMSY = 1.7 and 1.4 respectively). The Lc/Lc_opt ratio was ≤ 1 for E. fimbriata and M. cephalus, suggesting that the individuals caught for these species were too small. To reverse these bad stock statuses, catching individuals at Lc_opt, 25, 21, 43 and 18 cm for S. colias, E. fimbriata, M. cephalus and S. pilchardus, respectively should be a natural guarantee against recruitment failure and allow individuals to ensure the long-term survival of populations, in a context of data poor fisheries. In conclusion, this study shows that, despite limitations, the LBB model can provides indicators of stock status for species to encourage management measures, especially in data poor countries. It is hoped that these results can help to better assess many stocks currently considered too data poor to be assessed or at least encourage data collection effort on stocks discerned as in bad or critical status.https://doi.org/10.1371/journal.pone.0279768
spellingShingle Bocar Sabaly Baldé
Patrice Brehmer
Penda Diop Diaw
Length-based assessment of five small pelagic fishes in the Senegalese artisanal fisheries.
PLoS ONE
title Length-based assessment of five small pelagic fishes in the Senegalese artisanal fisheries.
title_full Length-based assessment of five small pelagic fishes in the Senegalese artisanal fisheries.
title_fullStr Length-based assessment of five small pelagic fishes in the Senegalese artisanal fisheries.
title_full_unstemmed Length-based assessment of five small pelagic fishes in the Senegalese artisanal fisheries.
title_short Length-based assessment of five small pelagic fishes in the Senegalese artisanal fisheries.
title_sort length based assessment of five small pelagic fishes in the senegalese artisanal fisheries
url https://doi.org/10.1371/journal.pone.0279768
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