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Auteur Lucena Frédou, F.; Frédou, T.; Gaertner, D.; Kell, L.; Potier, M.; Bach, P.; Travassos, P.; Hazin, F.; Ménard, F. url  doi
openurl 
  Titre Life history traits and fishery patterns of teleosts caught by the tuna longline fishery in the South Atlantic and Indian Oceans Type Article scientifique
  Année 2016 Publication Revue Abrégée Fisheries Research  
  Volume 179 Numéro (up) Pages 308-321  
  Mots-Clés Bycatch; Fishing impact; Tuna; Billfish; Ecosystem based fisheries management  
  Résumé The identification and mitigation of adverse effects of the bycatch of tuna longline fishery have been mainly developed and implemented for seabirds, sharks and turtles and, the knowledge on teleost bycatch for this fishery, remains very poor. This paper contributes to a comprehensive assessment of life history traits and fishery attributes of target and bycatch species caught by the tuna longline fishery in the South Atlantic and Indian Oceans. Data was compiled on seven life history traits and three fishery attributes for 33 and 27 teleost stocks caught by longliners in South Atlantic and Indian Oceans, respectively. In addition, each species was assigned into four categories describing the fate of the catch: target species for commercial use, bycatch species kept for consumption, bycatch species kept for commercial use and discarded bycatch. Life history traits and fishery attributes did not differ between oceans. However, non-target but commercialized species were smaller in the Atlantic Ocean. Teleosts caught by the tuna longline fishery was segregated into three main groups: (1) the fast growing species represented mainly by dolphinfishes (Coryphaena hippurus and C. equisellis), skipjack tuna (Katsuwonus pelamis), kawakawa (Euthynnus affinis), bullet tuna (Auxis rochei), snoek (Thyrsites atun) and blackfin tuna (Thunnus atlanticus); (2) target tunas and most other bycatch species which were part of an intermediate group and (3) billfishes including swordfish representing the large and slow growing species with moderate to high market values and unknown or highly uncertain stock status. Investment in some key life history traits (such as growth coefficient) and the development of quantitative or semi-quantitative approaches (stock assessment and Ecological Risk Assessment) should be priorized as precautionary management measures for these species.  
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  Editeur Lieu de Publication Éditeur  
  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0165-7836 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2405  
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Auteur NIEBLAS, A.-E.; DEMARCQ, H.; DRUSHKA, K.; SLOYAN, B.; BONHOMMEAU, S. url  openurl
  Titre Front variability and surface ocean features of the presumed southern bluefin tuna spawning grounds in the tropical southeast Indian Ocean Type Article scientifique
  Année 2014 Publication Revue Abrégée Deep-sea Research Part II-topical Studies In Oceanography  
  Volume 107 Numéro (up) Pages 64-76  
  Mots-Clés Front detection index; Indo-Australian region; Oceanic fronts; Southern bluefin tuna Thunnus maccoyii; Spawning grounds (10 degrees S-20 degrees S 105 degrees E-125 degrees E); Tropical southeast Indian Ocean  
  Résumé The southern bluefin tuna (SBT, Thunnus maccoyii) is an ecologically and economically valuable fish. However, surprisingly little is known about its critical early life history, a period when mortality is several orders of magnitude higher than at any other life stage, and when larvae are highly sensitive to environmental conditions. Ocean fronts can be important in creating favourable spawning conditions, as they are a convergence of water masses with different properties that can concentrate planktonic particles and lead to enhanced productivity. In this study, we examine the front activity within the only region where SBT have been observed to spawn: the tropical southeast Indian Ocean between Indonesia and Australia (10 degrees S-20 degrees S, 105 degrees E-125 degrees E). We investigate front activity and its relationship to ocean dynamics and surface features of the region. Results are also presented for the entire Indian Ocean (30 degrees N-45 degrees S, 20 degrees E-140 degrees E) to provide a background context. We use an extension of the Cayula and Cornillon algorithm to detect ocean fronts from satellite images of sea surface temperature (SST) and chlorophyll-a concentration (chl-a). Front occurrence represents the probability of occurrence of a front at each pixel of an image. Front intensity represents the magnitude of the difference between the two water masses that make up a front. Relative to the rest of the Indian Ocean, both SST and chl-a fronts in the offshore spawning region are persistent in occurrence and weak in intensity. Front occurrence and intensity along the Australian coast are high, with persistent and intense fronts found along the northwest and west coasts. Fronts in the tropical southeast Indian Ocean are shown to have strong annual variability and some moderate interannual variability. SST front occurrence is found to lead the Southern Oscillation Index by one year, potentially linked to warming and wind anomalies in the Indian Ocean. The surface ocean characteristics of the offshore SBT spawning region are found to be particularly stable compared to the rest of the Indian Ocean in terms of stable SST, low eddy kinetic energy, i.e., low mesoscale eddy activity, and low chl-a. However, this region has high front occurrence, but low front intensity of both SST and chl-a fronts. The potential impact of these oceanic features for SBT spawning is discussed.  
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  Editeur Lieu de Publication Éditeur  
  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0967-0645 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1131  
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Auteur Olson, R.J.; Young, J.W.; Menard, F.; Potier, M.; Allain, V.; Goni, N.; Logan, J.M.; Galvan-Magana, F. isbn  openurl
  Titre Bioenergetics, Trophic Ecology, and Niche Separation of Tunas Type Chapitre de livre
  Année 2016 Publication Revue Abrégée  
  Volume Numéro (up) Pages 199-344  
  Mots-Clés albacore thunnus-alalunga; atlantic bluefin tuna; eastern tropical pacific; fish aggregation devices; gulf-of-mexico; large pelagic fishes; oceanic top predators; predator-prey interactions; satellite archival tags; western indian-ocean  
  Résumé Tunas are highly specialized predators that have evolved numerous adaptations for a lifestyle that requires large amounts of energy consumption. Here we review our understanding of the bioenergetics and feeding dynamics of tunas on a global scale, with an emphasis on yellowfin, bigeye, skipjack, albacore, and Atlantic bluefin tunas. Food consumption balances bioenergetics expenditures for respiration, growth (including gonad production), specific dynamic action, egestion, and excretion. Tunas feed across the micronekton and some large zooplankton. Some tunas appear to time their life history to take advantage of ephemeral aggregations of crustacean, fish, and molluscan prey. Ontogenetic and spatial diet differences are substantial, and significant interdecadal changes in prey composition have been observed. Diet shifts from larger to smaller prey taxa highlight ecosystem-wide changes in prey availability and diversity and provide implications for changing bioenergetics requirements into the future. Where tunas overlap, we show evidence of niche separation between them; resources are divided largely by differences in diet percentages and size ranges of prey taxa. The lack of long-term data limits the ability to predict impacts of climate change on tuna feeding behaviour. We note the need for systematic collection of feeding data as part of routine monitoring of these species, and we highlight the advantages of using biochemical techniques for broad-scale analyses of trophic relations. We support the continued development of ecosystem models, which all too often lack the regional-specific trophic data needed to adequately investigate climate and fishing impacts.  
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  Auteur institutionnel Thèse  
  Editeur Elsevier Academic Press Inc Lieu de Publication San Diego Éditeur Curry, B.E.  
  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé Advances in Marine Biology, Vol 74  
  Volume de collection 74 Numéro de collection Edition  
  ISSN ISBN 978-0-12-803607-5 Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1661  
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Auteur Nikolic, N.; Morandeau, G.; Hoarau, L.; West, W.; Arrizabalaga, H.; Hoyle, S.; Nicol, S.J.; Bourjea, J.; Puech, A.; Farley, J.H.; Williams, A.J.; Fonteneau, A. url  doi
openurl 
  Titre Review of albacore tuna, Thunnus alalunga, biology, fisheries and management Type Article scientifique
  Année 2016 Publication Revue Abrégée Rev Fish Biol Fisheries  
  Volume Numéro (up) Pages 1-36  
  Mots-Clés Albacore; Tuna; Thunnus alalunga; Biology; Fishery  
  Résumé Albacore is one of the most important commercially harvested species in the world’s oceans. Despite a long history of scientific research, there is no global review or synthesis of knowledge about the species across all oceanic regions. We analysed 613 published studies that report on albacore and summarize the current state of knowledge on biology, stock structure, fisheries and management. To describe the trends in albacore fisheries, we examined the catch and effort databases of Regional Fisheries Management Organisations. The stocks of albacore are generally largest in the Pacific Ocean and smallest in the Mediterranean Sea. The biology of Atlantic and Pacific Ocean stocks are well documented, while the Indian Ocean and the Mediterranean Sea stocks are more data deficient. These two latter areas should be considered as priorities for future research and data collection in order to better understand the state of global stocks of albacore tuna. Improved information would also assist with delineating stock boundaries needed for sustainable management of this species.  
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  Editeur Lieu de Publication Éditeur  
  Langue en Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0960-3166, 1573-5184 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1707  
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Auteur Zhou, C.; He, P.; Xu, L.; Bach, P.; Wang, X.; Wan, R.; Tang, H.; Zhang, Y. url  doi
openurl 
  Titre The effects of mesoscale oceanographic structures and ambient conditions on the catch of albacore tuna in the South Pacific longline fishery Type Article scientifique
  Année 2020 Publication Revue Abrégée Fisheries Oceanography  
  Volume Numéro (up) Pages  
  Mots-Clés albacore tuna; environmental conditions; hook depth; longline; ocean eddy; ocean fronts; South Pacific Ocean  
  Résumé Albacore tuna (Thunnus alalunga) exhibit patchy concentrations associated with biological process at a wide range of spatial scales, resulting in variations in their catchability by fishing gears. Here, we investigated the association of catch variation for pelagic longlines in the South Pacific Ocean with oceanographic mesoscale structures (in horizontal dimension) and ambient conditions (in vertical dimension). The distribution of albacore tuna as indicated by catch per unit effort (CPUE) of longlines was significantly related to the presence of mesoscale structures, with higher CPUE found at locations closer to thermal fronts and with greater gradient magnitudes, as well as areas marked by peripheral contour line of the anticyclone indicated by Sea Surface Height Anomalies 0.05 m. Surface mesoscale current velocity had the negative effect on the catch, probably as a result of decreased catchability by shoaling the hook depth. Vertical distribution of albacore in the survey region of South Pacific Ocean was hardly restricted by ambient temperature and oxygen concentration, though effect of ambient temperature was relevant and showed a negatively linear correlation with CPUE at the range of 20–24°C. On the contrary, albacore distribution was evidently dominated by the water depth and showed strong preference on water depth of 200 m, which was likely a representative feeding layer. The presence of prey resources and their accessibility by albacore revealed by mesoscale structures in the biological and physical processes, and catchability determined by the location of the baited hooks comprehensively contribute to the variability of catch.  
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  Editeur Lieu de Publication Éditeur  
  Langue en Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1365-2419 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2732  
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