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Auteur Dagorn, L.; Holland, K.N.; Filmalter, J. url  doi
openurl 
  Titre (up) Are drifting FADs essential for testing the ecological trap hypothesis ? Type Article scientifique
  Année 2010 Publication Revue Abrégée Fisheries Research  
  Volume 106 Numéro Pages 60-63  
  Mots-Clés ecological; Fad; hypothesis; trap; Tunas  
  Résumé Because tropical tunas are known to aggregate around floating objects, it has been suggested that the large number of drifting fish aggregating devices (FADS) built and deployed by purse seiners could act as an 'ecological trap'. This hypothesis states that these networks of drifting FADS could take fish to areas where they would not normally go or retain them in places that they would otherwise leave. Because the ecological trap hypothesis was first advanced for drifting FADs, some have argued that only studies using drifting FADs can test this hypothesis. However, because working with drifting FADs is difficult, accepting this precept would preclude the scientific community from providing urgently needed information to organizations charged with management of fisheries that exploit drifting FADs. We argue that because both anchored and drifting FADs alter the natural environment, the more easily accessible anchored FADs can be used to test the ecological trap hypothesis. Also, based on a comparative scientific approach, we argue that understanding the behaviour of tunas around anchored FADs can improve our general understanding of tunas around all types of floating objects and help design new, well focused studies for drifting FADs. As anchored FADs are easier to access and offer a greater potential for research, we encourage scientists to design and conduct studies (in particular on the behaviour of fish at FADS) around the moored structures.  
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  Auteur institutionnel Thèse  
  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 LL @ pixluser @ collection 66  
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Auteur Guyader, O.; Robert, B.; Lionel, R. doi  openurl
  Titre (up) Assessing the number of moored fishing aggregating devices through aerial surveys: A case study from Guadeloupe Type Article scientifique
  Année 2017 Publication Revue Abrégée Fish Res.  
  Volume 185 Numéro Pages 73-82  
  Mots-Clés abundance; Aerial survey; behavior; Dolphinfish; fads; Fish aggregating devices (FAD); fisheries; floating objects; islands; knowledge; management; Small-scale fisheries management; transect surveys; yellowfin; Yellowfin tuna  
  Résumé Moored fish aggregating devices (MFADs) are increasingly being used in small-scale tropical fisheries to access pelagic fish species that are otherwise difficult to harvest in large numbers. Little attention has yet been paid to monitoring MFADs in coastal areas, however. This is most likely due to the small-scale nature of most fisheries that utilize them and the presumed lower impact of those fisheries on fish stocks and their ecosystems. In this paper, we examined the abundance and density of MFADs around Guadeloupe, using aerial line transect surveys. Estimated MFAD densities were found to be high compared with previously reported densities in this area, especially within the 22-45 km range offshore. We examine and discuss possible reasons for these high densities. The main drivers appear to be the target species dolphinfish (Coryphaena hippurus) and yellowfin tuna (Thunnus albacares) and related fishing behaviour. We present different approaches for reducing and monitoring MFADs densities, including the co-management of MFAD territorial use rights by fishing communities. (C) 2016 Elsevier B.V. All rights reserved.  
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  Auteur institutionnel Thèse  
  Editeur Lieu de Publication 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 0165-7836 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1696  
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Auteur Travassos Tolotti, M.; Forget, F.; Capello, M.; Filmalter, J.D.; Hutchinson, M.; Itano, D.; Holland, K.; Dagorn, L. doi  openurl
  Titre (up) Association dynamics of tuna and purse seine bycatch species with drifting fish aggregating devices (FADs) in the tropical eastern Atlantic Ocean Type Article scientifique
  Année 2020 Publication Revue Abrégée Fish Res.  
  Volume 226 Numéro Pages 105521  
  Mots-Clés Acoustic telemetry; behavior; Behavior; carcharhinus-falciformis; floating objects; Floating objects; obesus; pacific-ocean; patterns; Pelagic fish; Residence time; silky sharks; skipjack katsuwonus-pelamis; Tropical tuna; vertical movements; yellowfin thunnus-albacares  
  Résumé Several pelagic fish species are known to regularly associate with floating objects in the open ocean, including commercially valuable species. The tuna purse seine industry takes advantage of this associative behavior and has been increasingly deploying free-drifting man-made floating objects, also known as fish aggregating devices (FADs). Using passive acoustic telemetry, this study describes the associative dynamics of the main targeted tropical tuna species (Thunnus albacores, T. obelus and Katsuwonus pelamis), as well as three major bycatch species, silky shark (Carcharhinus falciformis), rainbow runner (Elagatis bipinmdata) and oceanic triggerfish (Canthidermis maculata). Short-term excursions away from the FADs were frequently performed by all tuna species as well by silky sharks. These excursions were characterized by a marked diel pattern, mainly occurring during nighttime. Rainbow runners and oceanic triggerfish were much more present at the FADs and rarely performed excursions. Average continuous residence times (CRTs) ranged from 6 days, for silky shark, up to 25 days for bigeye tuna. Similar to silky shark, average CRTs for skipjack tuna and oceanic triggerfish were less than 10 days. For yellowfin tuna and rainbow runner, CRTs averaged 19 and 16 days, respectively. Bigeye and yellowfin tuna remained associated to a single drifting FAD for a record of 55 days and 607 km traveled.  
  Adresse  
  Auteur institutionnel Thèse  
  Editeur Lieu de Publication 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 0165-7836 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000525305200009 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2772  
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Auteur Travassos Tolotti, M.; Filmalter, J.D.; Bach, P.; Travassos, P.; Seret, B.; Dagorn, L. url  doi
openurl 
  Titre (up) Banning is not enough: The complexities of oceanic shark management by tuna regional fisheries management organizations Type Article scientifique
  Année 2015 Publication Revue Abrégée Global Ecology and Conservation  
  Volume 4 Numéro Pages 1-7  
  Mots-Clés Bycatch; conservation; Fin trade; Pelagic shark; Tuna fisheries  
  Résumé Recently, declining populations of several pelagic shark species have led to global conservation concerns surrounding this group. As a result, a series of species-specific banning measures have been implemented by Regional Fishery Management Organizations (RFMOs) in charge of tuna fisheries, which include retention bans, finning bans and trading bans. There are both positive and negative aspects to most management measures, but generally, the positive aspects outweigh the negatives, ensuring the measure is beneficial to the resource and its users in the long term. Banning measures are a good first step towards the conservation of pelagic shark species, especially since they improve conservation awareness among fishers, managers and the public. Measures that impose total bans, however, can lead to negative impacts that may jeopardize the populations they were intended to protect. The majority of pelagic shark catches are incidental and most sharks die before they reach the vessel or after they are released. The legislation set out by RFMOs only prevents retention but not the actual capture or the mortality that may occur as a result. Managers should be fully aware that the development and implementation of mitigation measures are critical for a more effective conservation strategy.  
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  Auteur institutionnel Thèse  
  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 2351-9894 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1498  
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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 (up) 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 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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