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Auteur VAN BEVEREN, E.; BONHOMMEAU, S.; FROMENTIN, J.-M.; BIGOT, J.-L.; BOURDEIX, J.-H.; BROSSET, P.; ROOS, D.; SARAUX, C.
Titre Rapid changes in growth, condition, size and age of small pelagic fish in the Mediterranean Type Article scientifique
Année 2014 Publication Marine Biology Revue Abrégée
Volume 161 Numéro 8 Pages 1809-1822
Mots-Clés (up)
Résumé Since 2007, the ecosystem of the Gulf of Lions has shifted to a different regime, characterised by a low anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) biomass and a remarkably high sprat (Sprattus sprattus) biomass. Surprisingly, the abundance and recruitment of anchovy and sardine remained high. To understand which processes (bottom-up or top-down control, etc.) could have caused this shift, we studied the changes in body condition, growth and size and age of anchovy, sardine and sprat over 1984–1985 and 1992–2012, using data from scientific surveys. The annual age structure of anchovy and sardine was estimated using Bayesian mixture models based on size frequency data with priors on the age–length relationship derived from independent otolith readings. The results indicated periods during which anchovy and sardine were in an average (1992–2004), good (2005–2007) or poor (2008–2012) overall state of condition. For sardine, the shift towards smaller fish observed during these past 4 years was explained by a combination of slower growth and the disappearance of older individuals (ages 2+). Despite the increase in biomass of sprat since 2008, indications were found that sprat was also smaller than in the past. As growth and condition decreased and overexploitation has not been documented or suspected for those three species in this area, we propose that the current decline in sardine and anchovy biomass could be due to qualitative and/or quantitative modifications in the planktonic production (i.e. a bottom-up control) or mass mortalities of adults due to an epidemic disease.
Adresse Univ Montpellier 2, Res Unit EME UMR 212, F-34203 Sete, France.
Auteur institutionnel Thèse
Editeur Springer 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 0025-3162 ISBN Médium
Région Expédition Conférence
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 30335 collection 986
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Auteur Cooke, S.J.; Killen, S.S.; Metcalfe, J.D.; McKenzie, D.J.; Mouillot, D.; Jørgensen, C.; Peck, M.A.
Titre Conservation physiology across scales: insights from the marine realm Type Article scientifique
Année 2014 Publication Revue Abrégée Conservation Physiology
Volume 2 Numéro 1 Pages
Mots-Clés (up)
Résumé As the field of conservation physiology develops and becomes increasingly integrated with ecology and conservation science, the fundamental concept of scale is being recognized as important, particularly for ensuring that physiological knowledge is contextualized in a manner most relevant to policy makers, conservation practitioners and stakeholders. Failure to consider the importance of scale in conservation physiology—both the challenges and the opportunities that it creates—will impede the ability of this discipline to generate the scientific understanding needed to contribute to meaningful conservation outcomes. Here, we have focused on five aspects of scale: biological, spatial, temporal, allometric and phylogenetic. We also considered the scale of policy and policy application relevant to those five types of scale as well as the merits of upscaling and downscaling to explore and address conservation problems. Although relevant to all systems (e.g. freshwater, terrestrial) we have used examples from the marine realm, with a particular emphasis on fishes, given the fact that there is existing discourse regarding scale and its relevance for marine conservation and management. Our synthesis revealed that all five aspects of scale are relevant to conservation physiology, with many aspects inherently linked. It is apparent that there are both opportunities and challenges afforded by working across scales but, to understand mechanisms underlying conservation problems, it is essential to consider scale of all sorts and to work across scales to the greatest extent possible. Moreover, given that the scales in biological processes will often not match policy and management scales, conservation physiology needs to show how it is relevant to aspects at different policy/management scales, change the scales at which policy/management intervention is applied or be prepared to be ignored.
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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 ISBN Médium
Région Expédition Conférence
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 504
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Auteur Torres-Irineo, E.; Amandè, M.J.; Gaertner, D.; Delgado de Molina, A.; Murua, H.; Chavance, P.; Ariz, J.; Ruiz, J.; Lezama-Ochoa, N.
Titre Bycatch species composition over time by tuna purse-seine fishery in the eastern tropical Atlantic Ocean Type Article scientifique
Année 2014 Publication Revue Abrégée Biodiversity and Conservation
Volume 23 Numéro 5 Pages 1157-1173
Mots-Clés (up)
Résumé Within the Ecosystem-based fisheries management framework, we evaluated

the changes over time in bycatch species of the European tuna purse-seine fishery operating

in the eastern Atlantic Ocean. Bycatch data was collected during two scientific

observer programs conducted in the late 1990s and in the late 2000s. Over these two time

periods, we compared the temporal trends in bycatch species composition, the probability

of occurrence of functional groups per fishing set, the spatio-temporal species richness and

the potential impact on several species listed in the red list of the International Union for

Conservation of Nature (IUCN). The analyses were performed separately on the two main

fishing modes of the fleet, i.e. sets on free-swimming school sets and on fish aggregating

devices (FADs). Owing data quality constraints, we did not estimate bycatch rates. Ours

results showed that the species composition of sharks caught on FADs decreased over time.

The total species richness was higher for FAD sets than for free-swimming school sets (87

vs. 61 species respectively), such difference is common between fishing modes worldwide.
Adresse
Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue eng Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0960-3115 ISBN Médium
Région Expédition Conférence
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1546
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Auteur Merbt, S.N.; Auguet, J.C.; Blesa, A.; Marti, E.; Casamayor, E.O.
Titre Wastewater Treatment Plant Effluents Change Abundance and Composition of Ammonia-Oxidizing Microorganisms in Mediterranean Urban Stream Biofilms Type Article scientifique
Année 2014 Publication Revue Abrégée Microb Ecol
Volume Numéro Pages
Mots-Clés (up)
Résumé
Adresse
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 ISBN Médium
Région Expédition Conférence
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1312
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Auteur Restrepo-Ortiz, C.X.; Auguet, J.C.; Casamayor, E.O.
Titre Targeting spatiotemporal dynamics of planktonic SAGMGC-1 and segregation of ammonia-oxidizing thaumarchaeota ecotypes by newly designed primers and quantitative polymerase chain reaction Type Article scientifique
Année 2014 Publication Revue Abrégée Environmental Microbiology
Volume 16 Numéro 3 Pages 689-700
Mots-Clés (up)
Résumé The annual dynamics of three different ammonia-oxidizing archaea (AOA) ecotypes (amoA gene) and of the SAGMGC-1 (Nitrosotalea-like aquatic Thaumarchaeota) group (16S rRNA gene) were studied by newly designed specific primers and quantitative polymerase chain reaction analysis in a deep oligotrophic high mountain lake (Lake Redon, Limnological Observatory of the Pyrenees, Spain). We observed segregated distributions of the main AOA populations, peaking separately in time and space, and under different ammonia concentrations and irradiance conditions. Strong positive correlation in gene abundances was found along the annual survey between 16S rRNA SAGMAGC-1 and one of the amoA ecotypes suggesting the potential for ammonia oxidation in the freshwater SAGMAGC-1 clade. We also observed dominance of Nitrosotalea-like ecotypes over Nitrosopumilus-like (Marine Group 1.1a) and not the same annual dynamics for the two thaumarchaeotal clades. The fine scale segregation in space and time of the different AOA ecotypes indicated the presence of phylogenetically close but ecologically segregated AOA species specifically adapted to specific environmental conditions. It remains to be elucidated what would be such environmental drivers.
Adresse
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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 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1313
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