Cargando…

Tuna behaviour at anchored FADs inferred from Local Ecological Knowledge (LEK) of pole-and-line tuna fishers in the Maldives

The Maldives tuna fishery landings in 2018 were 148, 000 t and accounted for nearly a quarter of the global pole-and-line tuna catch. This fishery partially relies on a network of 55 anchored fish aggregating devices (AFADs) deployed around the archipelago. About one-third of the total pole-and-line...

Descripción completa

Detalles Bibliográficos
Autores principales: Jauharee, Ahmed Riyaz, Capello, Manuela, Simier, Monique, Forget, Fabien, Adam, Mohamed Shiham, Dagorn, Laurent
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8321119/
https://www.ncbi.nlm.nih.gov/pubmed/34324529
http://dx.doi.org/10.1371/journal.pone.0254617
_version_ 1783730775981555712
author Jauharee, Ahmed Riyaz
Capello, Manuela
Simier, Monique
Forget, Fabien
Adam, Mohamed Shiham
Dagorn, Laurent
author_facet Jauharee, Ahmed Riyaz
Capello, Manuela
Simier, Monique
Forget, Fabien
Adam, Mohamed Shiham
Dagorn, Laurent
author_sort Jauharee, Ahmed Riyaz
collection PubMed
description The Maldives tuna fishery landings in 2018 were 148, 000 t and accounted for nearly a quarter of the global pole-and-line tuna catch. This fishery partially relies on a network of 55 anchored fish aggregating devices (AFADs) deployed around the archipelago. About one-third of the total pole-and-line tuna catch is harvested at AFADs. Although the AFAD fishery has existed for 35 years, knowledge on the behaviour of tuna in the AFAD array is still limited, precluding the development of science-based fishery management. In this study, local ecological knowledge (LEK) of fishers was used to improve our understanding of tuna behaviour, through personal interviews of 54 pole-and-line fishers from different parts of the archipelago. Interview results suggest that during the northeast monsoon tuna are more abundant on the eastern side of the Maldives, while during the southwest monsoon they are more abundant on the western side of the Maldives. Most fishers believed that tuna tend to stay at the AFADs for 3 to 6 days and remain within 2 miles from the AFADs when they are associated. Fishers believe that strong currents is the main factor for tuna departure from AFADs, though high sea surface temperatures and stormy conditions were also thought to contribute to departures. Moderate currents are believed to be a favourable condition to form aggregations at the AFADs while other factors such as suitable temperature, prey and attractants enhance this aggregation. Fishers also believe that there are multiple schools segregated according to size and species at AFADs and that catchability is higher at dawn and in the late afternoon when the tuna occur shallower in the water column. This study is an important step towards engaging the Maldivian tuna fishers into a science-based fishery management.
format Online
Article
Text
id pubmed-8321119
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-83211192021-07-31 Tuna behaviour at anchored FADs inferred from Local Ecological Knowledge (LEK) of pole-and-line tuna fishers in the Maldives Jauharee, Ahmed Riyaz Capello, Manuela Simier, Monique Forget, Fabien Adam, Mohamed Shiham Dagorn, Laurent PLoS One Research Article The Maldives tuna fishery landings in 2018 were 148, 000 t and accounted for nearly a quarter of the global pole-and-line tuna catch. This fishery partially relies on a network of 55 anchored fish aggregating devices (AFADs) deployed around the archipelago. About one-third of the total pole-and-line tuna catch is harvested at AFADs. Although the AFAD fishery has existed for 35 years, knowledge on the behaviour of tuna in the AFAD array is still limited, precluding the development of science-based fishery management. In this study, local ecological knowledge (LEK) of fishers was used to improve our understanding of tuna behaviour, through personal interviews of 54 pole-and-line fishers from different parts of the archipelago. Interview results suggest that during the northeast monsoon tuna are more abundant on the eastern side of the Maldives, while during the southwest monsoon they are more abundant on the western side of the Maldives. Most fishers believed that tuna tend to stay at the AFADs for 3 to 6 days and remain within 2 miles from the AFADs when they are associated. Fishers believe that strong currents is the main factor for tuna departure from AFADs, though high sea surface temperatures and stormy conditions were also thought to contribute to departures. Moderate currents are believed to be a favourable condition to form aggregations at the AFADs while other factors such as suitable temperature, prey and attractants enhance this aggregation. Fishers also believe that there are multiple schools segregated according to size and species at AFADs and that catchability is higher at dawn and in the late afternoon when the tuna occur shallower in the water column. This study is an important step towards engaging the Maldivian tuna fishers into a science-based fishery management. Public Library of Science 2021-07-29 /pmc/articles/PMC8321119/ /pubmed/34324529 http://dx.doi.org/10.1371/journal.pone.0254617 Text en © 2021 Jauharee et al https://creativecommons.org/licenses/by/4.0/This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
spellingShingle Research Article
Jauharee, Ahmed Riyaz
Capello, Manuela
Simier, Monique
Forget, Fabien
Adam, Mohamed Shiham
Dagorn, Laurent
Tuna behaviour at anchored FADs inferred from Local Ecological Knowledge (LEK) of pole-and-line tuna fishers in the Maldives
title Tuna behaviour at anchored FADs inferred from Local Ecological Knowledge (LEK) of pole-and-line tuna fishers in the Maldives
title_full Tuna behaviour at anchored FADs inferred from Local Ecological Knowledge (LEK) of pole-and-line tuna fishers in the Maldives
title_fullStr Tuna behaviour at anchored FADs inferred from Local Ecological Knowledge (LEK) of pole-and-line tuna fishers in the Maldives
title_full_unstemmed Tuna behaviour at anchored FADs inferred from Local Ecological Knowledge (LEK) of pole-and-line tuna fishers in the Maldives
title_short Tuna behaviour at anchored FADs inferred from Local Ecological Knowledge (LEK) of pole-and-line tuna fishers in the Maldives
title_sort tuna behaviour at anchored fads inferred from local ecological knowledge (lek) of pole-and-line tuna fishers in the maldives
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8321119/
https://www.ncbi.nlm.nih.gov/pubmed/34324529
http://dx.doi.org/10.1371/journal.pone.0254617
work_keys_str_mv AT jauhareeahmedriyaz tunabehaviouratanchoredfadsinferredfromlocalecologicalknowledgelekofpoleandlinetunafishersinthemaldives
AT capellomanuela tunabehaviouratanchoredfadsinferredfromlocalecologicalknowledgelekofpoleandlinetunafishersinthemaldives
AT simiermonique tunabehaviouratanchoredfadsinferredfromlocalecologicalknowledgelekofpoleandlinetunafishersinthemaldives
AT forgetfabien tunabehaviouratanchoredfadsinferredfromlocalecologicalknowledgelekofpoleandlinetunafishersinthemaldives
AT adammohamedshiham tunabehaviouratanchoredfadsinferredfromlocalecologicalknowledgelekofpoleandlinetunafishersinthemaldives
AT dagornlaurent tunabehaviouratanchoredfadsinferredfromlocalecologicalknowledgelekofpoleandlinetunafishersinthemaldives