bascule de visibilité Search & Display Options

Tout Sélectionner    Désélectionner
 |   | 
Détails
   print
  Enregistrements Liens
Auteur Lopez, J.; Moreno, G.; Lennert-Cody, C.; Maunder, M.; Sancristobal, I.; Caballero, A.; Dagorn, L. doi  openurl
  Titre Environmental preferences of tuna and non-tuna species associated with drifting fish aggregating devices (DFADs) in the Atlantic Ocean, ascertained through fishers' echo-sounder buoys Type Article scientifique
  Année 2017 Publication Revue Abrégée Deep-Sea Res. Part II-Top. Stud. Oceanogr.  
  Volume 140 Numéro Pages 127-138  
  Mots-Clés behavior; catch rates; Echo-sounder buoy; Environmental preferences; equatorial atlantic; fad; floating objects; french-polynesia; gamm; habitat; pacific-ocean; Pelagic fish; Purse seine; thunnus-albacares; Tropical tuna; Tuna; western indian-ocean  
  Résumé Understanding the relationship between environmental variables and pelagic species concentrations and dynamics is helpful to improve fishery management, especially in a changing environment. Drifting fish aggregating device (DFAD)-associated tuna and non-tuna biomass data from the fishers' echo-sounder buoys operating in the Atlantic Ocean have been modelled as functions of oceanographic (Sea Surface Temperature, Chlorophyll-a, Salinity, Sea Level Anomaly, Thermocline depth and gradient, Geostrophic current, Total Current, Depth) and DFAD variables (DFAD speed, bearing and soak time) using Generalized Additive Mixed Models (GAMMs). Biological interaction (presence of non-tuna species at DFADs) was also included in the tuna model, and found to be significant at this time scale. All variables were included in the analyses but only some of them were highly significant, and variable significance differed among fish groups. In general, most of the fish biomass distribution was explained by the ocean productivity and DFAD-variables. Indeed, this study revealed different environmental preferences for tunas and non-tuna species and suggested the existence of active habitat selection. This improved assessment of environmental and DFAD effects on tuna and non-tuna catchability in the purse seine tuna fishery will contribute to transfer of better scientific advice to regional tuna commissions for the management and conservation of exploited resources.  
  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 0967-0645 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel (up) MARBEC @ alain.herve @ collection 2177  
Lien permanent pour cet enregistrement
 

 
Auteur Briscoe, D.K.; Hobday, A.J.; Carlisle, A.; Scales, K.; Eveson, J.P.; Arrizabalaga, H.; Druon, J.N.; Fromentin, J.-M. doi  openurl
  Titre Ecological bridges and barriers in pelagic ecosystems Type Article scientifique
  Année 2017 Publication Revue Abrégée Deep-Sea Res. Part II-Top. Stud. Oceanogr.  
  Volume 140 Numéro Pages 182-192  
  Mots-Clés arctic marine mammals; atlantic bluefin tuna; Billfish; Brazilian episode; climate-change; el-nino; interannual variation; Marine mammal; marlin makaira-nigricans; Migration corridors; Oceanographic features; population connectivity; satellite archival tags; sea-turtles; site fidelity; species distribution; thunnus-maccoyii; Tuna  
  Résumé Many highly mobile species are known to use persistent pathways or corridors to move between habitat patches in which conditions are favorable for particular activities, such as breeding or foraging. In the marine realm, environmental variability can lead to the development of temporary periods of anomalous oceanographic conditions that can connect individuals to areas of habitat outside a population's usual range, or alternatively, restrict individuals from areas usually within their range, thus acting as ecological bridges or ecological barriers. These temporary features can result in novel or irregular trophic interactions and changes in population spatial dynamics, and, therefore, may have significant implications for management of marine ecosystems. Here, we provide evidence of ecological bridges and barriers in different ocean regions, drawing upon five case studies in which particular oceanographic conditions have facilitated or restricted the movements of individuals from highly migratory species. We discuss the potential population-level significance of ecological bridges and barriers, with respect to the life history characteristics of different species, and inter- and intra-population variability in habitat use. Finally, we summarize the persistence of bridge dynamics with time, our ability to monitor bridges and barriers in a changing climate, and implications for forecasting future climate mediated ecosystem change.  
  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 0967-0645 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel (up) MARBEC @ alain.herve @ collection 2178  
Lien permanent pour cet enregistrement
 

 
Auteur Pecoraro, C.; Babbucci, M.; Franch, R.; Rico, C.; Papetti, C.; Chassot, E.; Bodin, N.; Cariani, A.; Bargelloni, L.; Tinti, F. doi  openurl
  Titre The population genomics of yellowfin tuna (Thunnus albacares) at global geographic scale challenges current stock delineation Type Article scientifique
  Année 2018 Publication Revue Abrégée Sci Rep  
  Volume 8 Numéro Pages 13890  
  Mots-Clés archival tag data; atlantic bluefin tuna; connectivity; conservation; divergence; fisheries management; habitat utilization; loci; pacific-ocean; relatedness  
  Résumé Yellowfin tuna, Thunnus albacares, is one of the most important seafood commodities in the world. Despite its great biological and economic importance, conflicting evidence arises from classical genetic and tagging studies concerning the yellowfin tuna population structure at local and global oceanic scales. Access to more powerful and cost effective genetic tools would represent the first step towards resolving the population structure of yellowfin tuna across its distribution range. Using a panel of 939 neutral Single Nucleotide Polymorphisms (SNPs), and the most comprehensive data set of yellowfin samples available so far, we found genetic differentiation among the Atlantic, Indian and Pacific oceans. The genetic stock structure analysis carried out with 33 outlier SNPs, putatively under selection, identified discrete populations within the Pacific Ocean and, for the first time, also within the Atlantic Ocean. Stock assessment approaches that consider genetic differences at neutral and adaptive genomic loci should be routinely implemented to check the status of the yellowfin tuna, prevent illegal trade, and develop more sustainable management measures.  
  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 2045-2322 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel (up) MARBEC @ alain.herve @ collection 2437  
Lien permanent pour cet enregistrement
 

 
Auteur Capello, M.; Deneubourg, J.L.; Robert, M.; Holland, K.N.; Schaefer, K.M.; Dagorn, L. doi  openurl
  Titre Population assessment of tropical tuna based on their associative behavior around floating objects Type Article scientifique
  Année 2016 Publication Revue Abrégée Sci Rep  
  Volume 6 Numéro Pages 36415  
  Mots-Clés abundance; aerial surveys; archival tag data; bluefin tuna; continental-shelf; fish aggregating devices; katsuwonus-pelamis; pacific-ocean; tagging data; thunnus-albacares  
  Résumé Estimating the abundance of pelagic fish species is a challenging task, due to their vast and remote habitat. Despite the development of satellite, archival and acoustic tagging techniques that allow the tracking of marine animals in their natural environments, these technologies have so far been underutilized in developing abundance estimations. We developed a new method for estimating the abundance of tropical tuna that employs these technologies and exploits the aggregative behavior of tuna around floating objects (FADs). We provided estimates of abundance indices based on a simulated set of tagged fish and studied the sensitivity of our method to different association dynamics, FAD numbers, population sizes and heterogeneities of the FAD-array. Taking the case study of yellowfin tuna (Thunnus albacares) acoustically-tagged in Hawaii, we implemented our approach on field data and derived for the first time the ratio between the associated and the total population. With more extensive and long-term monitoring of FAD-associated tunas and good estimates of the numbers of fish at FADs, our method could provide fisheries-independent estimates of populations of tropical tuna. The same approach can be applied to obtain population assessments for any marine and terrestrial species that display associative behavior and from which behavioral data have been acquired using acoustic, archival or satellite tags.  
  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 2045-2322 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel (up) MARBEC @ alain.herve @ collection 1682  
Lien permanent pour cet enregistrement
 

 
Auteur Van Beveren, E.; Fromentin, J.-M.; Bonhommeau, S.; Nieblas, A.-E.; Metral, L.; Brisset, B.; Jusup, M.; Bauer, R.K.; Brosset, P.; Saraux, C. doi  openurl
  Titre Predator-prey interactions in the face of management regulations: changes in Mediterranean small pelagic species are not due to increased tuna predation Type Article scientifique
  Année 2017 Publication Revue Abrégée Can. J. Fish. Aquat. Sci.  
  Volume 74 Numéro 9 Pages 1422-1430  
  Mots-Clés anchovy engraulis-encrasicolus; atlantic bluefin tuna; Energy density; fish condition; fisheries; food-consumption; Proximate composition; sea; thunnus-thynnus; Yellowfin tuna  
  Résumé Recently, the abundance of young Atlantic bluefin tuna (Thunnus thynnus) tripled in the northwestern Mediterranean following effective management measures. We investigated whether its predation on sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) could explain their concurrent size and biomass decline, which caused a fishery crisis. Combining the observed diet composition of bluefin tuna, their modelled daily energy requirements, their population size, and the abundance of prey species in the area, we calculated the proportion of the prey populations that were consumed by bluefin tuna annually over 2011-2013. To assess whether tuna could alter the size structure of the three small pelagic fish populations (anchovy, sardine, and sprat (Sprattus sprattus)), the size distributions of the consumed prey species were compared with those of the wild populations. We estimated that the annual consumption of small pelagic fish by bluefin tuna is less than 2% of the abundance of these populations. Furthermore, size selectivity patterns were not observed. We thus concluded that tuna predation is unlikely to be the main cause of major changes in the small pelagic fish populations from this area.  
  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 0706-652x ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel (up) MARBEC @ alain.herve @ collection 2195  
Lien permanent pour cet enregistrement
Tout Sélectionner    Désélectionner
 |   | 
Détails
   print

Save Citations:
Export Records: