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Auteur Krause, J.; Herbert-Read, J.E.; Seebacher, F.; Domenici, P.; Wilson, A.D.M.; Marras, S.; Svendsen, M.B.S.; Strombom, D.; Steffensen, J.F.; Krause, S.; Viblanc, P.E.; Couillaud, P.; Bach, P.; Sabarros, P.S.; Zaslansky, P.; Kurvers, R.H.J.M. doi  openurl
  Titre Injury-mediated decrease in locomotor performance increases predation risk in schooling fish Type Article scientifique
  Année 2017 Publication Revue Abrégée Philos. Trans. R. Soc. B-Biol. Sci.  
  Volume 372 Numéro 1727 Pages (down) 20160232  
  Mots-Clés animal groups; Behavior; danger; fish schools; geometry; group-living; killer whales; locomotion; organization; Predation; prey interactions; selfish herd; spatial position; spatial positions; vertebrates  
  Résumé The costs and benefits of group living often depend on the spatial position of individuals within groups and the ability of individuals to occupy preferred positions. For example, models of predation events for moving prey groups predict higher mortality risk for individuals at the periphery and front of groups. We investigated these predictions in sardine (Sardinella aurita) schools under attack from group hunting sailfish (Istiophorus platypterus) in the open ocean. Sailfish approached sardine schools about equally often from the front and rear, but prior to attack there was a chasing period in which sardines attempted to swim away from the predator. Consequently, all sailfish attacks were directed at the rear and peripheral positions of the school, resulting in higher predation risk for individuals at these positions. During attacks, sailfish slash at sardines with their bill causing prey injury including scale removal and tissue damage. Sardines injured in previous attacks were more often found in the rear half of the school than in the front half. Moreover, injured fish had lower tail-beat frequencies and lagged behind uninjured fish. Injuries inflicted by sailfish bills may, therefore, hinder prey swimming speed and drive spatial sorting in prey schools through passive self-assortment. We found only partial support for the theoretical predictions from current predator-prey models, highlighting the importance of incorporating more realistic predator-prey dynamics into these models. This article is part of the themed issue 'Physiological determinants of social behaviour in animals'.  
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  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 0962-8436 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2161  
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Auteur Amélineau, F.; Grémillet, D.; Bonnet, D.; Bot, T.L.; Fort, J. url  doi
openurl 
  Titre Where to Forage in the Absence of Sea Ice? Bathymetry As a Key Factor for an Arctic Seabird Type Article scientifique
  Année 2016 Publication Revue Abrégée Plos One  
  Volume 11 Numéro 7 Pages (down) e0157764  
  Mots-Clés Birds; Copepods; Foraging; Predation; Seabirds; Sea ice; Trophic interactions; Zooplankton  
  Résumé The earth is warming at an alarming rate, especially in the Arctic, where a marked decline in sea ice cover may have far-ranging consequences for endemic species. Little auks, endemic Arctic seabirds, are key bioindicators as they forage in the marginal ice zone and feed preferentially on lipid-rich Arctic copepods and ice-associated amphipods sensitive to the consequences of global warming. We tested how little auks cope with an ice-free foraging environment during the breeding season. To this end, we took advantage of natural variation in sea ice concentration along the east coast of Greenland. We compared foraging and diving behaviour, chick diet and growth and adult body condition between two years, in the presence versus nearby absence of sea ice in the vicinity of their breeding site. Moreover, we sampled zooplankton at sea when sea ice was absent to evaluate prey location and little auk dietary preferences. Little auks foraged in the same areas both years, irrespective of sea ice presence/concentration, and targeted the shelf break and the continental shelf. We confirmed that breeding little auks showed a clear preference for larger copepod species to feed their chick, but caught smaller copepods and nearly no ice-associated amphipod when sea ice was absent. Nevertheless, these dietary changes had no impact on chick growth and adult body condition. Our findings demonstrate the importance of bathymetry for profitable little auk foraging, whatever the sea-ice conditions. Our investigations, along with recent studies, also confirm more flexibility than previously predicted for this key species in a warming Arctic.  
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  ISSN 1932-6203 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1592  
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Auteur Marques, R.; Darnaude, A.M.; Crochemore, S.; Bouvier, C.; Bonnet, D. url  doi
openurl 
  Titre Molecular approach indicates consumption of jellyfish by commercially important fish species in a coastal Mediterranean lagoon Type Article scientifique
  Année 2019 Publication Revue Abrégée Marine Environmental Research  
  Volume 152 Numéro Pages (down) 104787  
  Mots-Clés Eel; Gut content; Medusae; Polyps; Predation; Quantitative PCR; Seabream; Thau lagoon  
  Résumé Until recently, jellyfish have been ignored as an important source of food, due to their low nutritional value. Here, quantitative PCR was used to detect and quantify the DNA of the jellyfish Aurelia coerulea in the gut contents of commercially important fish species from the Thau Lagoon. Individuals from five fish species were collected during two different periods: the bloom period, when the pelagic stages of A. coerulea are abundant, and the post-bloom period, when only the benthic stage – polyps – is present in the lagoon. The DNA of A. coerulea was detected in the guts of 41.9% of the fish analysed, belonging to four different species. The eel Anguilla anguilla and the seabream Sparus aurata were important jellyfish consumers during the bloom and post-bloom periods, respectively. These results provide new insights on the potential control of jellyfish populations and on jellyfish importance as a food source for exploited fishes.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0141-1136 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2615  
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Auteur McKenzie, D.J.; Belao, T.C.; Killen, S.S.; Rantin, F.T. doi  openurl
  Titre To boldly gulp: standard metabolic rate and boldness have context-dependent influences on risk-taking to breathe air in a catfish Type Article scientifique
  Année 2015 Publication Revue Abrégée J. Exp. Biol.  
  Volume 218 Numéro 23 Pages (down) 3762-3770  
  Mots-Clés african catfish; animal personality; Bimodal respiration; clarias-gariepinus; ecological consequences; Energy metabolism; european sea bass; Hypoxia; individual variation; oncorhynchus-mykiss; Personality; personality-traits; predation risk; Respiratory partitioning; Risk-taking; wild-type zebrafish  
  Résumé The African sharptooth catfish Clarias gariepinus has bimodal respiration, it has a suprabranchial air-breathing organ alongside substantial gills. We used automated bimodal respirometry to reveal that undisturbed juvenile catfish (N=29) breathed air continuously in normoxia, with a marked diurnal cycle. Air breathing and routine metabolic rate (RMR) increased in darkness when, in the wild, this nocturnal predator forages. Aquatic hypoxia (20% air saturation) greatly increased overall reliance on air breathing. We investigated whether two measures of risk taking to breathe air, namely absolute rates of aerial O-2 uptake ((M) over dotO(2), air) and the percentage of RMR obtained from air (% (M) over dotO(2), air), were influenced by individual standard metabolic rate (SMR) and boldness. In particular, whether any influence varied with resource availability (normoxia versus hypoxia) or relative fear of predation (day versus night). Individual SMR, derived from respirometry, had an overall positive influence on (M) over dotO(2), air across all contexts but a positive influence on % (M) over dotO(2), air only in hypoxia. Thus, a pervasive effect of SMR on air breathing became most acute in hypoxia, when individuals with higher O-2 demand took proportionally more risks. Boldness was estimated as time required to resume air breathing after a fearful stimulus in daylight normoxia (T-res). Although T-res had no overall influence on (M) over dotO(2), air or % (M) over dotO(2), air, there was a negative relationship between Tres and % (M) over dotO(2), air in daylight, in normoxia and hypoxia. There were two Tres response groups, 'bold' phenotypes with Tres below 75 min (N= 13) which, in daylight, breathed proportionally more air than 'shy' phenotypes with Tres above 115 min (N= 16). Therefore, individual boldness influenced air breathing when fear of predation was high. Thus, individual energy demand and personality did not have parallel influences on the emergent tendency to take risks to obtain a resource; their influences varied in strength with context.  
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  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 0022-0949 ISBN Médium  
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  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1429  
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Auteur Travers, M.; Shin, Y.-J.; Jennings, S.; Machu, E.; Huggett, J.A.; Field, J.G.; Cury, P. url  doi
openurl 
  Titre Two-way coupling versus one-way forcing of plankton and fish models to predict ecosystem changes in the Benguela Type Article scientifique
  Année 2009 Publication Revue Abrégée Ecological Modelling  
  Volume 220 Numéro 21 Pages (down) 3089-3099  
  Mots-Clés Benguela upwelling; Ecem 07; End-to-end approach; food web; marine; Marine ecosystem model coupling; Predation  
  Résumé 'End-to-end' models have been adopted in an attempt to capture more of the processes that influence the ecology of marine ecosystems and to make system wide predictions of the effects of fishing and climate change. Here, we develop an end-to-end model by coupling existing models that describe the dynamics of low (ROMS-N(2)P(2)Z(2)D(2)) and high trophic levels(OSMOSE). ROMS-N(2)P(2)Z(2)D(2) is a biogeochemical model representing phytoplankton and zooplankton seasonal dynamics forced by hydrodynamics in the Benguela upwelling ecosystem. OSMOSE is an individual-based model representing the dynamics of several species of fish, linked through opportunistic and size-based trophic interactions. The models are coupled through a two-way size-based predation process. Plankton provides prey for fish, and the effects of predation by fish on the plankton are described by a plankton mortality term that is variable in space and time. Using the end-to-end model, we compare the effects of two-way coupling versus one-way forcing of the fish model with the plankton biomass field. The fish-induced mortality on plankton is temporally variable, in part explained by seasonal changes in fish biomass. Inclusion of two-way feedback affects the seasonal dynamics of plankton groups and usually reduces the amplitude of variation in abundance (top-down effect). Forcing and coupling lead to different predicted food web structures owing to changes in the dominant food chain which is supported by plankton (bottom-up effect). Our comparisons of one-way forcing and two-way coupling show how feedbacks may affect abundance, food web structure and food web function and emphasise the need to critically examine the consequences of different model architectures when seeking to predict the effects of fishing and climate change.  
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  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
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  ISSN 0304-3800 ISBN Médium  
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  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 29  
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