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A Methodological Framework to Estimate the Site Fidelity of Tagged Animals Using Passive Acoustic Telemetry ArchiMer
Capello, Manuela; Robert, Marianne; Soria, Marc; Potin, Gael; Itano, David; Holland, Kim; Deneubourg, Jean-louis; Dagorn, Laurent.
The rapid expansion of the use of passive acoustic telemetry technologies has facilitated unprecedented opportunities for studying the behavior of marine organisms in their natural environment. This technological advance would greatly benefit from the parallel development of dedicated methodologies accounting for the variety of timescales involved in the remote detection of tagged animals related to instrumental, environmental and behavioral events. In this paper we propose a methodological framework for estimating the site fidelity (“residence times”) of acoustic tagged animals at different timescales, based on the survival analysis of continuous residence times recorded at multiple receivers. Our approach is validated through modeling and applied on two...
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Ano: 2015 URL: https://archimer.ifremer.fr/doc/00275/38589/37116.pdf
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Aggregation processes of Tuna under Drifting Fish Aggregating Devices (DFADS) assessed through fisher's echosounder buoy in the Indian Ocean ArchiMer
Baidai, Y; Dagorn, Laurent; Amande, Mj; Gaertner, Daniel; Capello, Manuela.
The aggregative behavior of tuna around floating object is widely exploited by the industrial purse-seine fishery, which deploy thousands of floating objects each year in all oceans in order to improve their catches. These fish aggregating devices (FADs) are generally equipped with echosounder buoys that can collect acoustic data, conferring to these devices the status of privileged observation platforms for the fish communities that aggregate. Using a classification model based on supervised learning algorithms trained on M3I buoy data, we were able to translate the acoustic data collected along the trajectories of 5748 drifting FADs newly deployed between 2016 and 2018 in the Indian Ocean into presence or absence of tuna aggregation. Analysis of the...
Tipo: Text Palavras-chave: Echosounders; Drifting fish aggregating devices (FAD); Tropical tunas; Behaviour.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00615/72694/71700.pdf
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An update on the post-release survival of silky sharks incidentally captured by tuna purse seine vessels in the Indian Ocean ArchiMer
Filmalter, John; Forget, Fabien; Poisson, Francois; Vernet, Anne-lise; Dagorn, Laurent.
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Ano: 2012 URL: http://archimer.ifremer.fr/doc/00130/24090/22071.pdf
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Balanced harvest in the real world. Scientific, policy and operational issues in an ecosystem approach to fisheries ArchiMer
Garcia, Serge M.; Bianchi, Gabriella; Charles, Anthony; Kolding, Jeppe; Rice, Jake; Rochet, Marie-joelle; Zhou, Shijie; Delius, Gustav; Reid, David; Van Zwieten, Paul A. M.; Atcheson, Megan; Bartley, Devin; Borges, Lisa; Bundy, Alida; Dagorn, Laurent; Dunn, Daniel C.; Hall, Martin; Heino, Mikko; Jacobsen, Brigitte; Jacobsen, Nis S.; Law, Richard; Makino, Mitsutaku; Martin, Felix; Skern-mauritzen, Mette; Suuronen, Petri; Symons, Despina.
The concept of the Ecosystem Approach has entered the fishery harvesting discussions both from fishery perspectives (Reykjavik Declaration; FAO 2003 Annex to the Code of Conduct and from the principles of the Ecosystem Approach adopted by the CBD in 1995. Both perspectives establish the need to maintain ecosystem structure and functioning, whether for sustainable use of biodiversity (CBD) or simply to keep exploited ecosystems healthy and productive (fisheries). In response, the “Balanced Harvest” (BH) concept was suggested by a group of scientists brought together by the IUCN Fisheries Experts Group during the CBD CoP 10 in 2010. The meeting and the BH concept as consolidated there highlighted some of the collateral ecological effects of current fishing...
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Ano: 2015 URL: http://archimer.ifremer.fr/doc/00255/36575/35113.pdf
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Collaborative research: Development of a manual on elasmobranch handling and release best practices in tropical tuna purse-seine fisheries ArchiMer
Poisson, Francois; Seret, Bernard; Vernet, Anne-lise; Goujon, Michel; Dagorn, Laurent.
The reduction of by-catch mortality is an objective of the ecosystem approach to fisheries and a request made by consumers. Elasmobranchs, an important component of the French tropical tuna purse seine fishery by-catch, are currently thrown back into the sea. Fishers interact with various types of elasmobranchs that range widely in size, weight and shape, and could pose various degrees of danger to the crew. A diversity of discarding practices within the fleet were reported, some practices were considered suitable, others needed to be adapted and improved and others simply had to be banned. The majority of the crews were likely to improve their handling practices if they were presented with practical suggestions that were quick and easy. Combining...
Tipo: Text Palavras-chave: By-catch; Tropical purse-seiner; Sharks; Handling/release practices; Mitigation; Fish welfare.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00159/27008/28367.pdf
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DCP employés par les pêcheries artisanales et industrielles : une question d'échelle. L’utilisation et le développement technique des DCP au coeur de la conférence de Tahiti sur les DCP ArchiMer
Taquet, Marc; Blanc, Michel; Dagorn, Laurent; Filmalter, John David; Fonteneau, Alain; Forget, Fabien; Gaertner, Jean-claude; Galzin, René; Gervain, Paul; Goujon, Michel; Guillotreau, Patrice; Guyader, Olivier; Hall, Martin; Holland, Kim; Itano, David; Monteagudo, Jean-pierre; Morales-nin, Beatriz; Reynal, Lionel; Sharp, Michael; Sokimi, Williams; Tanetoa, Mainui; Yen Kai Sun, Stephen.
Tipo: Text
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00115/22657/20383.pdf
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Deep diving behavior observed in yellowfin tuna (Thunnus albacares) ArchiMer
Dagorn, Laurent; Holland, Kim N.; Hallier, Jean-pierre; Taquet, Marc; Moreno, Gala; Sancho, Gorka; Itano, David; Aumeeruddy, Ryaz; Girard, Charlotte; Million, Julien; Fonteneau, Alain.
Yellowfin tuna (Thunnus albacares) are known to preferentially occupy the Surface mixed layer above the thermocline and it has been Suggested that they are physiologically restricted to water lerriperatt.11-CS no more than 8 degrees C colder than Surface waters. However, we here report for dive data acquired from a large yellowfin tuna which demonstrate for the first time that this species is indeed capable of making prolonged dives into deep cold waters. A yellowfin tuna (134 cm fork length) caught near ail anchored fish aggregating device (FAD) in the Seychelles (Western Indian Ocean) was equipped with all internally implanted archival tag and released. The fish was recaptured 98 days later. As predicted for this species, this fish spent 85% of its time...
Tipo: Text Palavras-chave: Indian ocean; Yellowfin tuna; Swimming speed; Diving behavior; Vertical movements; Archival tap.
Ano: 2006 URL: http://archimer.ifremer.fr/doc/2006/publication-1402.pdf
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Global comparison of post release survival of silky sharks caught by tropical tuna purse seine vessels ArchiMer
Filmalter, J; Hutchinson, M; Poisson, Francois; Eddy, W; Brill, R; Bernal, D; Itano, D; Muir, J; Vernet, Al; Holland, K; Dagorn, Laurent.
ISSF, in collaboration with other bycatch mitigation projects, such as the EU MADE project and the ORTHONGEL bycatch project, has undertaken tagging experiments to quantify the fishery impact on silky sharks (Carcharhinus falciformis) incidentally captured in the global tropical tuna purse seine fishery. Silky sharks commonly associate with floating objects in the open ocean environment. This phenomenon has been observed throughout the species’ cosmopolitan distribution range. Several other pelagic and coastal species also display this behaviour, but its prevalence in three tropical tuna species (skipjack, Katsuwonus pelamis, yellowfin, Thunnus albacares, and bigeye T. obesus, tunas) has led to the commercial exploitation of this behaviour. Industrial...
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Ano: 2015 URL: https://archimer.ifremer.fr/doc/00481/59243/61967.pdf
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Global spatial risk assessment of sharks under the footprint of fisheries ArchiMer
Queiroz, Nuno; Humphries, Nicolas E.; Couto, Ana; Vedor, Marisa; Da Costa, Ivo; Sequeira, Ana M. M.; Mucientes, Gonzalo; Santos, Antonio M; Abascal, Francisco J.; Abercrombie, Debra L.; Abrantes, Katya; Acuna-marrero, David; Afonso, Andre S.; Afonso, Pedro; Anders, Darrell; Araujo, Gonzalo; Arauz, Randall; Bach, Pascal; Barnett, Adam; Bernal, Diego; Berumen, Michael L.; Lion, Sandra Bessudo; Bezerra, Natalia P. A.; Blaison, Antonin V.; Block, Barbara A.; Bond, Mark E.; Bonfil, Ramon; Bradford, Russell W.; Braun, Camrin D.; Brooks, Edward J.; Brooks, Annabelle; Brown, Judith; Bruce, Barry D.; Byrne, Michael E.; Campana, Steven E.; Carlisle, Aaron B.; Chapman, Demian D.; Chapple, Taylor K.; Chisholm, John; Clarke, Christopher R.; Clua, Eric G.; Cochran, Jesse E. M.; Crochelet, Estelle C.; Dagorn, Laurent; Daly, Ryan; Cortes, Daniel Devia; Doyle, Thomas K.; Drew, Michael; Duffy, Clinton A. J.; Erikson, Thor; Espinoza, Eduardo; Ferreira, Luciana C.; Ferretti, Francesco; Filmalter, John D.; Fischer, G. Chris; Fitzpatrick, Richard; Fontes, Jorge; Forget, Fabien; Fowler, Mark; Francis, Malcolm P.; Gallagher, Austin J.; Gennari, Enrico; Goldsworthy, Simon D.; Gollock, Matthew J.; Green, Jonathan R.; Gustafson, Johan A.; Guttridge, Tristan L.; Guzman, Hector M.; Hammerschlag, Neil; Harman, Luke; Hazin, Fabio H. V.; Heard, Matthew; Hearn, Alex R.; Holdsworth, John C.; Holmes, Bonnie J.; Howey, Lucy A.; Hoyos, Mauricio; Hueter, Robert E.; Hussey, Nigel E.; Huveneers, Charlie; Irion, Dylan T.; Jacoby, David M. P.; Jewell, Oliver J. D.; Johnson, Ryan; Jordan, Lance K. B.; Jorgensen, Salvador J.; Joyce, Warren; Daly, Clare A. Keating; Ketchum, James T.; Klimley, A. Peter; Kock, Alison A.; Koen, Pieter; Ladino, Felipe; Lana, Fernanda O.; Lea, James S. E.; Llewellyn, Fiona; Lyon, Warrick S.; Macdonnell, Anna; Macena, Bruno C. L.; Marshall, Heather; Mcallister, Jaime D.; Mcauley, Rory; Meyer, Michael A.; Morris, John J.; Nelson, Emily R.; Papastamatiou, Yannis P.; Patterson, Toby A.; Penaherrera-palma, Cesar; Pepperell, Julian G.; Pierce, Simon J.; Poisson, Francois; Quintero, Lina Maria; Richardson, Andrew J.; Rogers, Paul J.; Rohner, Christoph A.; Rowat, David R. L.; Samoilys, Melita; Semmens, Jayson M.; Sheaves, Marcus; Shillinger, George; Shivji, Mahmood; Singh, Sarika; Skomal, Gregory B.; Smale, Malcolm J.; Snyders, Laurenne B.; Soler, German; Soria, Marc; Stehfest, Kilian M.; Stevens, John D.; Thorrold, Simon R.; Tolotti, Mariana T.; Towner, Alison; Travassos, Paulo; Tyminski, John P.; Vandeperre, Frederic; Vaudo, Jeremy J.; Watanabe, Yuuki Y.; Weber, Sam B.; Wetherbee, Bradley M.; White, Timothy D.; Williams, Sean; Zarate, Patricia M.; Harcourt, Robert; Hays, Graeme C.; Meekan, Mark G.; Thums, Michele; Irigoien, Xabier; Eguiluz, Victor M.; Duarte, Carlos M.; Sousa, Lara L.; Simpson, Samantha J.; Southall, Emily J.; Sims, David W..
Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from...
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Ano: 2019 URL: https://archimer.ifremer.fr/doc/00575/68662/67587.pdf
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Guide de bonnes pratiques pour réduire la mortalité des requins et des raies capturés accidentellement par les thoniers senneurs tropicaux ArchiMer
Poisson, Francois; Vernet, Anne-lise; Seret, Bernard; Dagorn, Laurent.
Tipo: Text
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00130/24093/22087.pdf
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Hydrological and trophic characteristics of tuna habitat: consequences on tuna distribution and longline catchability ArchiMer
Bertrand, Arnaud; Josse, Erwan; Bach, Pascal; Gros, Philippe; Dagorn, Laurent.
We studied relationships between tropical tunas (albacore (Thunnus alalunga), bigeye (Thunnus obesus), and yellowfin (Thunnus albacares)) and their biotic and abiotic environments through simultaneous acoustic observations of tunas and their prey, experimental longline catch, and oceanographic data in French Polynesia. Vertical habitat limits were estimated based on temperature and dissolved oxygen at capture data. We then studied tuna-micronekton relationships to better understand how tuna occupy the pelagic space, At a regional scale, tunas were more abundant in areas rich in prey with favourable hydrological conditions. Inside such areas, at the scale of a longline set, however, the longline catches were maximal only when prey were not distributed in...
Tipo: Text Palavras-chave: Hydrological; Acoustic observations; Tunas.
Ano: 2002 URL: http://archimer.ifremer.fr/doc/2002/publication-733.pdf
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Impact of increasing deployment of artificial floating objects on the spatial distribution of social fish species ArchiMer
Sempo, Gregory; Dagorn, Laurent; Robert, Marianne; Deneubourg, Jean-louis.
1. Approximately 300 pelagic fish species naturally aggregate around floating objects (FOBs) at the surface of the oceans. Currently, more than 50% of the world catch of tropical tuna comes from the industrial tuna fisheries around drifting FOBs. Greater understanding of the complex decision-making processes leading to this aggregation pattern and the impact of the massive release of artificial FOBs by fishermen on the spatial distribution and management of tuna is needed. 2. We analyse how the interplay between social (relationships between individuals) and non-social (responses to the environment) behaviours may affect the spatial distribution of a population in a multi-FOB environment. Taking the example of tropical tunas associating with FOBs and using...
Tipo: Text Palavras-chave: Behaviour-based modelling; Bycatch; FAD; FOB; Sustainable fishery; Tuna.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00151/26275/24439.pdf
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Intra-individual behavioral variability displayed by tuna at fish aggregating devices (FADs) ArchiMer
Robert, Marianne; Dagorn, Laurent; Filmalter, John David; Deneubourg, Jean-louis; Itano, David; Holland, Kim.
Fishers have exploited the associative behavior displayed by several pelagic fish species with floating objects for decades, through the use of man-made fish aggregating devices (FADs), which facilitate the capture of such species. However, our understanding of this associative behavior and its adaptive value is poor and the scientific community is ill-equipped to provide fishery managers with science-based recommendations on the impacts of FADs on ecosystems. In an array of 13 anchored FADs around Oahu, Hawaii, USA, 72 yellowfin tuna Thunnus albacares were equipped with internal acoustic tags, which facilitated the continuous monitored of their presence and absence around each FAD using automated acoustic receivers. Data were analyzed using survival...
Tipo: Text Palavras-chave: Behavioral variability; Fish aggregating device; FAD; Yellowfin tuna; Acoustic tagging; Residence time; Survival curve.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00140/25098/23207.pdf
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Le comportement des thons tropicaux modélisé selon les principes de la vie artificielle IRD
Dagorn, Laurent.
La pêche au thon tropical constitue une activité économique très importante. Les scientifiques étudient l'ensemble du système pêche (poisson, environnement, pêcheur, marché) afin de proposer des moyens de gestion efficaces. Le présent travail concerne le comportement des poissons dans leur milieu et un paradoxe est à l'origine de nos recherches : comment les thons, dont les besoins énergétiques sont très élevés, peuvent-ils survivre dans l'environnement globalement pauvre que sont les deux cents premiers mètres des mers tropicales? L'étude du comportement des thons tropicaux n'est pas aisée compte tenu de la difficulté d'observation des animaux et de leur milieu. Nous avons choisi d'utiliser des outils et concepts issus du domaine scientifique de la Vie...
Tipo: Text Palavras-chave: THON; ECOETHOLOGIE; MIGRATION; MODELISATION; SIMULATION; ETUDE THEORIQUE; RELATION ESPECE ENVIRONNEMENT; COMPORTEMENT GREGAIRE; VIE ARTIFICIELLE.
Ano: 1995 URL: http://www.documentation.ird.fr/hor/fdi:41254
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Mapping tuna occurrence under drifting fish aggregating devices from Fisher’s Echosounder buoys in Indian Ocean ArchiMer
Baidai, Yannick; Dagorn, Laurent; Amande, Mj; Gaertner, Daniel; Capello, Manuela.
Echosounder buoys data obtained from instrumented drifting FADs represent an unprecedented source of information for assessing the spatio-temporal distribution of tropical tuna. Using machine learning algorithms, we transformed acoustic data collected from one of the main echosounder buoys models used by the French purse seine fleet (M3I) into presence/absence of tuna aggregations, enabling the measurement of the amount of inhabited FADs on a given spatiotemporal strata. This paper presents the spatial and temporal distribution of the proportion of drifting fish aggregating devices (DFADs) occupied by tuna aggregations relative to the total number of FADs in the Indian Ocean on a monthly basis, on a 5° grid for year 2016. The perspectives opened up by this...
Tipo: Text Palavras-chave: Echosounders; Drifting fish aggregating devices (FAD); Tropical tunas; Abundance.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00592/70454/68576.pdf
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Mortality rate of silky sharks ( Carcharhinus falciformis) caught in the tropical tuna purse seine fishery in the Indian Ocean ArchiMer
Poisson, Francois; Filmalter, John David; Vernet, Anne-lise; Dagorn, Laurent.
Scientists aboard French purse seine vessels recorded the number and condition of silky sharks (Carcharhinus falciformis) caught during three fishing cruises in the Indian Ocean. A sample of 31 individuals that showed signs of life were tagged with satellite tags to investigate their postrelease mortality. The majority of individuals (95%) were brought on board using the brailer. Combining the proportion of sharks that were dead (72%) and the mortality rate of those released (48%), the overall mortality rate of brailed individuals was 85%. Few individuals (5%) were not brailed as they were entangled and landed during the hauling process. The survival rate of these individuals was high, with an overall mortality rate of meshed individuals of 18%. The...
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Ano: 2014 URL: http://archimer.ifremer.fr/doc/00187/29870/28379.pdf
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Oceanic landscape concept and operational fisheries oceanography IRD
Petit, Michel; Dagorn, Laurent; Léna, Philippe; Slepoukha, Michel; Ramos, A.G.; Stretta, Jean-Michel.
Tipo: Text Palavras-chave: OCEANOGRAPHIE DES PECHES; TELEDETECTION SPATIALE; SURVEILLANCE; PRODUCTION HALIEUTIQUE; GESTION DES PECHES; SATELLITE NOAA; SATELLITE TIROS N; RADIOMETRIE; TEMPERATURE DE SURFACE; CONVERGENCE MARINE.
Ano: 1994 URL: http://www.documentation.ird.fr/hor/fdi:010024409
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Possible universality in the size distribution of fish schools IRD
Bonabeau, E.; Dagorn, Laurent.
Tipo: Text Palavras-chave: THON; DISTRIBUTION STATISTIQUE; DISTRIBUTION SPATIALE; MODELE PHYSIQUE; MODELISATION; DISTRIBUTION DE TAILLE; BANC DE POISSONS.
Ano: 1995 URL: http://www.documentation.ird.fr/hor/fdi:010024411
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Robbing Peter to pay Paul: replacing unintended cross-taxa conflicts with intentional tradeoffs by moving from piecemeal to integrated fisheries bycatch management ArchiMer
Gilman, Eric; Chaloupka, Milani; Dagorn, Laurent; Hall, Martin; Hobday, Alistair; Musyl, Michael; Pitcher, Tony; Poisson, Francois; Restrepo, Victor; Suuronen, Petri.
Bycatch in fisheries can have profound effects on the abundance of species with relatively low resilience to increased mortality, can alter the evolutionary characteristics and concomitant fitness of affected populations through heritable trait-based selective removals, and can alter ecosystem functions, structure and services through food web trophic links. We challenge current piecemeal bycatch management paradigms, which reduce the mortality of one taxon of conservation concern at the unintended expense of others. Bycatch mitigation measures may also reduce intraspecific genetic diversity. We drew examples of broadly prescribed ‘best practice’ methods to mitigate bycatch that result in unintended cross-taxa conflicts from pelagic longline, tuna purse...
Tipo: Text Palavras-chave: Bycatch; Conflicts; Decision support tool; Fisheries-induced evolution; Holistic management; Integrated management.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00475/58693/61206.pdf
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The aggregation of tuna around floating objects: What could be the underlying social mechanisms? ArchiMer
Robert, Marianne; Dagorn, Laurent; Deneubourg, Jean Louis.
Several empirical and theoretical studies have shown how the exploitation of food sources, the choice of resting sites or other types of collective decision-making in heterogeneous environments are facilitated and modulated by social interactions between conspecifics. It is well known that many pelagic fishes live in schools and that this form of gregarious behavior provides advantages in terms of food intake and predator avoidance efficiency. However, the influence of social behavior in the formation of aggregations by tuna under floating objects (FOBs) is poorly understood. In this work, we investigated the collective patterns generated by different theoretical models, which either include or exclude social interactions between conspecifics, in the...
Tipo: Text Palavras-chave: Models Of Aggregation; Monte Carlo multi-agents simulations; Fish Aggregating Devices; Social Behavior.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00195/30638/29091.pdf
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