Trends in deep-water shark fisheries in the Azores

Detalhes bibliográficos
Autor(a) principal: Aguiar, Ana Raquel Batista
Data de Publicação: 2015
Tipo de documento: Dissertação
Idioma: eng
Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
Texto Completo: http://hdl.handle.net/10773/15485
Resumo: Deep-sea resources have been increasingly exploited, and due to that, several ecosystems and species have been considerably affected. Deep-water sharks populations have been of the most disturbed by practices of unselected fisheries, bycatch and discard, mainly due to their low commercial value. Those practices make deep-water sharks very vulnerable to overfishing given their life-history traits, increasing their extinction risk. With the prohibition of the direct fishery, and implementation of quotas and TACs (Total Allowable Catches) regarding the deep-sea shark landings, the official landings have dramatically decreased after the 1990s. However, the IUU (Illegal, unreported and unregulated) catch has exponentially increased. With the analysis of catch per unit effort (CPUE), the depths, and the mean weight of the individuals over the years for each one of the nine most caught species in the Azores, we produced a descriptive analysis of the effect of fisheries in those species. The results show that some of these species have been suffering from a great fishing pressure, and their populations will be greatly affected in the near future if drastic measures are not taken when it comes to managing their long term sustainability.
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spelling Trends in deep-water shark fisheries in the AzoresBiologia marinhaEcossistemas marinhos - Águas profundas - Arquipélago dos Açores (Portugal)Tubarões - Espécies ameaçadasPesca - SustentabilidadeDeep-sea resources have been increasingly exploited, and due to that, several ecosystems and species have been considerably affected. Deep-water sharks populations have been of the most disturbed by practices of unselected fisheries, bycatch and discard, mainly due to their low commercial value. Those practices make deep-water sharks very vulnerable to overfishing given their life-history traits, increasing their extinction risk. With the prohibition of the direct fishery, and implementation of quotas and TACs (Total Allowable Catches) regarding the deep-sea shark landings, the official landings have dramatically decreased after the 1990s. However, the IUU (Illegal, unreported and unregulated) catch has exponentially increased. With the analysis of catch per unit effort (CPUE), the depths, and the mean weight of the individuals over the years for each one of the nine most caught species in the Azores, we produced a descriptive analysis of the effect of fisheries in those species. The results show that some of these species have been suffering from a great fishing pressure, and their populations will be greatly affected in the near future if drastic measures are not taken when it comes to managing their long term sustainability.Os recursos do mar profundo têm sido cada vez mais explorados, e devido a isso, vários ecossistemas e espécies têm sido gravemente afectados. As populações de tubarões de profundidade são das mais perturbadas, especialmente pelas práticas de pesca não seletivas, capturas acessórias e descarte, principalmente devido ao seu baixo valor comercial. Estas práticas tornam os tubarões de profundidade muito vulneráveis à sobrepesca dadas as suas características de história de vida, aumentando assim o seu risco de extinção . Com a proibição da pesca direta, e a implementação de quotas e TACs (Capturas Totais Admissíveis) na pesca de tubarões de profundidade, as capturas oficiais têm vindo a decrescer. No entanto, as capturas não reportadas têm vindo a aumentar exponencialmente. Com a análise da captura por unidade de esforço (CPUE), da profundidade, e do peso médio dos indivíduos ao longo dos anos de cada umas das 9 espécies de tubarões mais pescadas nos Açores, conseguimos fazer uma análise descritiva do efeito das pescas nestas espécies. Os resultados mostram que algumas destas espécies têm vindo a sofrer uma grande pressão por parte da pesca, e que as suas populações serão gravemente afetadas num futuro próximo se não forem tomadas medidas drásticas no que toca à gestão da sua sustentabilidade a longo prazo.Universidade de Aveiro2018-07-20T14:00:53Z2015-01-05T00:00:00Z2015-01-052017-01-05T15:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://hdl.handle.net/10773/15485TID:201564220engAguiar, Ana Raquel Batistainfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2024-02-22T11:28:39Zoai:ria.ua.pt:10773/15485Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T02:50:51.766563Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse
dc.title.none.fl_str_mv Trends in deep-water shark fisheries in the Azores
title Trends in deep-water shark fisheries in the Azores
spellingShingle Trends in deep-water shark fisheries in the Azores
Aguiar, Ana Raquel Batista
Biologia marinha
Ecossistemas marinhos - Águas profundas - Arquipélago dos Açores (Portugal)
Tubarões - Espécies ameaçadas
Pesca - Sustentabilidade
title_short Trends in deep-water shark fisheries in the Azores
title_full Trends in deep-water shark fisheries in the Azores
title_fullStr Trends in deep-water shark fisheries in the Azores
title_full_unstemmed Trends in deep-water shark fisheries in the Azores
title_sort Trends in deep-water shark fisheries in the Azores
author Aguiar, Ana Raquel Batista
author_facet Aguiar, Ana Raquel Batista
author_role author
dc.contributor.author.fl_str_mv Aguiar, Ana Raquel Batista
dc.subject.por.fl_str_mv Biologia marinha
Ecossistemas marinhos - Águas profundas - Arquipélago dos Açores (Portugal)
Tubarões - Espécies ameaçadas
Pesca - Sustentabilidade
topic Biologia marinha
Ecossistemas marinhos - Águas profundas - Arquipélago dos Açores (Portugal)
Tubarões - Espécies ameaçadas
Pesca - Sustentabilidade
description Deep-sea resources have been increasingly exploited, and due to that, several ecosystems and species have been considerably affected. Deep-water sharks populations have been of the most disturbed by practices of unselected fisheries, bycatch and discard, mainly due to their low commercial value. Those practices make deep-water sharks very vulnerable to overfishing given their life-history traits, increasing their extinction risk. With the prohibition of the direct fishery, and implementation of quotas and TACs (Total Allowable Catches) regarding the deep-sea shark landings, the official landings have dramatically decreased after the 1990s. However, the IUU (Illegal, unreported and unregulated) catch has exponentially increased. With the analysis of catch per unit effort (CPUE), the depths, and the mean weight of the individuals over the years for each one of the nine most caught species in the Azores, we produced a descriptive analysis of the effect of fisheries in those species. The results show that some of these species have been suffering from a great fishing pressure, and their populations will be greatly affected in the near future if drastic measures are not taken when it comes to managing their long term sustainability.
publishDate 2015
dc.date.none.fl_str_mv 2015-01-05T00:00:00Z
2015-01-05
2017-01-05T15:00:00Z
2018-07-20T14:00:53Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/masterThesis
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dc.identifier.uri.fl_str_mv http://hdl.handle.net/10773/15485
TID:201564220
url http://hdl.handle.net/10773/15485
identifier_str_mv TID:201564220
dc.language.iso.fl_str_mv eng
language eng
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dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Universidade de Aveiro
publisher.none.fl_str_mv Universidade de Aveiro
dc.source.none.fl_str_mv reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron:RCAAP
instname_str Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron_str RCAAP
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reponame_str Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
collection Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
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