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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 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.  
  Adresse  
  Auteur institutionnel Thèse  
  Editeur Elsevier Academic Press Inc Lieu de Publication (down) 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  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1661  
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Auteur Poisson, F.; Abascal Crespo, F.; Ellis, J.R.; Chavance, P.; Pascal, B.; Santos, M.N.; Seret, B.; Korta, M.; Coelho, R.; Ariz, J.; Murua, H. doi  openurl
  Titre Technical mitigation measures for sharks and rays in fisheries for tuna and tuna-like species: turning possibility into reality Type Article scientifique
  Année 2016 Publication Revue Abrégée Aquat. Living Resour.  
  Volume 29 Numéro 4 Pages 402  
  Mots-Clés at-vessel mortality; Bycatch; california recreational fishery; circle hooks; eastern pacific-ocean; Elasmobranch; great-barrier-reef; j-hook performance; Mitigation; mortality; pelagic; pelagic longline fishery; postrelease survival; Purse seine fishery; rare-earth-metal; tuna regional fishery management organizations  
  Résumé Tuna fisheries have been identified as one of the major threats to populations of other marine vertebrates, including sea turtles, sharks, seabirds and marine mammals. The development of technical mitigation measures (MM) in fisheries is part of the code of conduct for responsible fisheries. An in-depth analysis of the available literature regarding bycatch mitigation in tuna fisheries with special reference to elasmobranchs was undertaken. Studies highlighting promising MMs were reviewed for four tuna fisheries (longline, purse seine, driftnets and gillnet, and rod and line – including recreational fisheries). The advantages and disadvantages of different MMs are discussed and assessed based on current scientific knowledge. Current management measures for sharks and rays in tuna Regional Fishery Management Organizations (t-RFMOs) are presented. A review of relevant studies examining at-vessel and postrelease mortality of elasmobranch bycatch is provided. This review aims to help fisheries managers identify pragmatic solutions to reduce mortality on pelagic elasmobranchs (and other higher vertebrates) whilst minimizing impacts on catches of target tuna species. Recent research efforts have identified several effective MMs that, if endorsed by t-RFMOs, could reduce elasmobranchs mortality rate in international tropical purse seine tuna fisheries. In the case of longline fisheries, the number of operational effective MMs is very limited. Fisheries deploying driftnets in pelagic ecosystems are suspected to have a high elasmobranchs bycatch and their discard survival is uncertain, but no effective MMs have been field validated for these fisheries. The precautionary bans of such gear by the EU and by some t-RFMOs seem therefore appropriate. Recreational tuna fisheries should be accompanied by science-based support to reduce potential negative impacts on shark populations. Priorities for research and management are identified and discussed.  
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  Auteur institutionnel Thèse  
  Editeur Lieu de Publication (down) Éditeur  
  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0990-7440 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2056  
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Auteur Escalle, L.; Murua, H.; Amande, J.M.; Arregui, I.; Chavance, P.; Delgado de Molina, A.; Gaertner, D.; Fraile, I.; Filmalter, J.D.; Santiago, J.; Forget, F.; Arrizabalaga, H.; Dagorn, L.; Mérigot, B. url  doi
openurl 
  Titre Post-capture survival of whale sharks encircled in tuna purse-seine nets: tagging and safe release methods Type Article scientifique
  Année 2016 Publication Revue Abrégée Aquatic Conserv: Mar. Freshw. Ecosyst.  
  Volume 25 Numéro 4 Pages 433-447  
  Mots-Clés mega fauna; post-release mortality; Psat; Rhincodon typus; tropical tuna purse-seine  
  Résumé 1. Whale shark, the world's largest fish, is believed to be particularly vulnerable owing to its biological characteristics (slow growth, late maturation, great longevity) and is listed as Vulnerable by IUCN and included in Appendix II of CITES. 2. Whale sharks are occasionally encircled in tropical tuna purse-seine nets, throughout this global fishery. Although apparent immediate survival rates following encirclement and release have recently been assessed through scientific onboard observer programmes, a more rigorous methodology is still required for studying post-released survival. 3. This work provides a method for applying pop-up satellite tags and reports an enhanced release procedure for whale sharks. The first assessment of survival after release from purse-seine nets involved six whale sharks tagged between May and September 2014 in the eastern tropical Atlantic Ocean. Five tags transmitted data: three popped up as programmed (after 30 days), while two surfaced prematurely (one after 21 and the other after 71 days (programmed to pop off after 30 and 90 days, respectively)) but showed no sign of unusual behaviour. 4. Overall, whale sharks survived at least 21 days (one at least 71 days) after release from purse-seine nets. These observations based on five large individuals (total length > 8 m), suggest that whale sharks have a good chance of survival when released with the proposed method. 5. Additional tagging in this and other oceans, especially of juveniles which may be more sensitive to encirclement and release operations, is essential to further assess whale shark post-release survival rates in tuna purse-seine fisheries. Copyright © 2016 John Wiley & Sons, Ltd.  
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  Editeur Lieu de Publication (down) 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 1099-0755 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1547  
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Auteur Pons, M.; Branch, T.A.; Melnychuk, M.C.; Jensen, O.P.; Brodziak, J.; Fromentin, J.M.; Harley, S.J.; Haynie, A.C.; Kell, L.T.; Maunder, M.N.; Parma, A.M.; Restrepo, V.R.; Sharma, R.; Ahrens, R.; Hilborn, R. url  doi
openurl 
  Titre Effects of biological, economic and management factors on tuna and billfish stock status Type Article scientifique
  Année 2017 Publication Revue Abrégée Fish Fish  
  Volume 18 Numéro 1 Pages 1-21  
  Mots-Clés Fisheries management; marine conservation; stock assessment; stock status; Tuna fisheries  
  Résumé Commercial tunas and billfishes (swordfish, marlins and sailfish) provide considerable catches and income in both developed and developing countries. These stocks vary in status from lightly exploited to rebuilding to severely depleted. Previous studies suggested that this variability could result from differences in life-history characteristics and economic incentives, but differences in exploitation histories and management measures also have a strong effect on current stock status. Although the status (biomass and fishing mortality rate) of major tuna and billfish stocks is well documented, the effect of these diverse factors on current stock status and the effect of management measures in rebuilding stocks have not been analysed at the global level. Here, we show that, particularly for tunas, stocks were more depleted if they had high commercial value, were long-lived species, had small pre-fishing biomass and were subject to intense fishing pressure for a long time. In addition, implementing and enforcing total allowable catches (TACs) had the strongest positive influence on rebuilding overfished tuna and billfish stocks. Other control rules such as minimum size regulations or seasonal closures were also important in reducing fishing pressure, but stocks under TAC implementations showed the fastest increase of biomass. Lessons learned from this study can be applied in managing large industrial fisheries around the world. In particular, tuna regional fisheries management organizations should consider the relative effectiveness of management measures observed in this study for rebuilding depleted large pelagic stocks.  
  Adresse  
  Auteur institutionnel Thèse  
  Editeur Lieu de Publication (down) 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 1467-2979 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2079  
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Auteur Mullon, C.; Guillotreau, P.; Galbraith, E.D.; Fortilus, J.; Chaboud, C.; Bopp, L.; Aumont, O.; Kaplan, D. url  doi
openurl 
  Titre Exploring future scenarios for the global supply chain of tuna Type Article scientifique
  Année 2017 Publication Revue Abrégée Deep Sea Research Part II: Topical Studies in Oceanography  
  Volume 140 Numéro Pages 251-267  
  Mots-Clés climate change; Global supply chain; marine protected area; Scenarios; Tuna  
  Résumé The abundance of tuna, an important top predator that ranges throughout tropical and subtropical oceans, is now largely determined by fishing activity. Fishing activity, in turn, is determined by the interaction of fish availability, fishing capacity, fishing costs and global markets for tuna products. In the face of overfishing, the continued sustainable supply of tuna is likely to require improved global governance, that would benefit from modeling frameworks capable of integrating market forces with the availability of fish in order to consider alternative future projections. Here we describe such a modeling framework, in which we develop several simple, contrasting scenarios for the development of the tuna supply chain in order to illustrate the utility of the approach for global evaluation of management strategies for tuna and other complex, stock-structured fisheries. The model includes multiple national and multi-national fishing fleets, canneries and fresh/frozen markets, and connects these to global consumers using a network of flows. The model is calibrated using recent data on fish catch, cannery and fresh/frozen production, and consumption. Scenarios explore the control on future outcomes in the global tuna fishery by representing, in a simple way, the effects of (1) climate change, (2) changes in the global demand for tuna, and (3) changes in the access to fishing grounds (marine reserves). The results emphasize the potential importance of increasing demand in provoking a global collapse, and suggest that controlling tuna production by limiting technical efficiency is a potential countermeasure. Finally we discuss the outcomes in terms of potential extensions of the scenario approach allowed by this global network model of the tuna supply chain.  
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  Auteur institutionnel Thèse  
  Editeur Lieu de Publication (down) 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  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2098  
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