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Auteur Annasawmy, P.; Ternon, J.-F.; Cotel, P.; Cherel, Y.; Romanov, E.; Roudaut, G.; Lebourges-Dhaussy, A.; Menard, F.; Marsac, F. doi  openurl
  Titre Micronekton distributions and assemblages at two shallow seamounts of the south-western Indian Ocean: Insights from acoustics and mesopelagic trawl data Type Article scientifique
  Année 2019 Publication Revue Abrégée Prog. Oceanogr.  
  Volume 178 Numéro Pages (down) 102161  
  Mots-Clés Acoustics; deep-scattering layer; diel migration; fish aggregations; mesoscale features; Micronekton; mozambique channel; myctophid fishes; pelagic communities; Seamount; Seamount-associated fauna; South-western Indian Ocean; species identification; target strength; vertical-distribution  
  Résumé Micronekton distributions and assemblages were investigated at two shallow seamounts of the south-western Indian Ocean using a combination of trawl data and a multi-frequency acoustic visualisation technique. La Pa rouse seamount (summit depth similar to 60 m) is located on the outskirts of the oligotrophic Indian South Subtropical Gyre (ISSG) province with weak mesoscale activities and low primary productivity all year round. The “MAD-Ridge” seamount (thus termed in this study; similar to 240 m) is located in the productive East African Coastal (EAFR) province with high mesoscale activities to the south of Madagascar. Higher micronekton species richness was recorded at MAD-Ridge compared to La Perouse. Resulting productivity at MAD-Ridge seamount was likely due to the action of mesoscale eddies advecting productivity and larvae from the Madagascar shelf rather than local dynamic processes such as Taylor column formation. Mean micronekton abundance/biomass, as estimated from mesopelagic trawl catches, were lower over the summit compared to the vicinity of the seamounts, due to net selectivity and catchability and depth gradient on micronekton assemblages. Mean acoustic densities in the night shallow scattering layer (SSL: 10-200 m) over the summit were not significantly different compared to the vicinity (within 14 nautical miles) of MAD-Ridge. At La Perouse and MAD-Ridge, the night and day SSL were dominated by common diel vertically migrant and non-migrant micronekton species respectively. While seamount-associated mesopelagic fishes such as Diaphus suborbitalis (La Perouse and MAD-Ridge) and Benthosema fibula= performed diel vertical migrations (DVM) along the seamounts' flanks, seamount-resident benthopelagic fishes, including Cookeolus japonicus (MAD-Ridge), were aggregated over MAD-Ridge summit. Before sunrise, mid-water migrants initiated their vertical migration from the intermediate to the deep scattering layer (DSL, La Perouse: 500-650 m; MAD-Ridge: 400-700 m) or deeper. During sunrise, the other taxa contributing to the night SSL exhibited a series of vertical migration events from the surface to the DSL or deeper until all migrants have reached the DSL before daytime. Possible mechanisms leading to the observed patterns in micronekton vertical and horizontal distributions are discussed. This study contributes to a better understanding of how seamounts influence the DVM, horizontal distribution and community composition of micronekton and seamount-associated/resident species at two poorly studied shallow topographic features in the south-western Indian Ocean.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0079-6611 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000496861900013 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2666  
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Auteur Campbell, S.J.; Darling, E.S.; Pardede, S.; Ahmadia, G.; Mangubhai, S.; Amkieltiela; Estradivari; Maire, E. doi  openurl
  Titre Fishing restrictions and remoteness deliver conservation outcomes for Indonesia's coral reef fisheries Type Article scientifique
  Année 2020 Publication Revue Abrégée Conserv. Lett.  
  Volume Numéro Pages (down) e12698  
  Mots-Clés data-poor fisheries; dynamics; food webs; gear restrictions; management; marine protected areas; small-scale fisheries; South East Asia; targets  
  Résumé Coral reef fisheries depend on reef fish biomass to support ecosystem functioning and sustainable fisheries. Here, we evaluated coral reefs across 4,000 km of the Indonesian archipelago to reveal a large gradient of biomass, from 17,000 kg/ha. Trophic pyramids characterized by planktivore dominance emerged at high biomass, suggesting the importance of pelagic pathways for reef productivity. Total biomass and the biomass of most trophic groups were higher within gear restricted and no-take management, but the greatest biomass was found on unmanaged remote reefs. Within marine protected areas (MPAs), 41.6% and 43.6% of gear restricted and no-take zones, respectively, met a global biomass target of 500 kg/ha, compared with 71.8% of remote sites. To improve conservation outcomes for Indonesia's biodiverse and economically important coral reef fisheries, our results suggest to: (1) strengthen management within Indonesia's existing MPAs and (2) precautionarily manage remote reefs with high biomass.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 1755-263x ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000510789900001 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2733  
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Auteur Saeedi, H.; Reimer, J.D.; Brandt, M.; Dumais, P.-O.; Jazdzewska, A.M.; Jeffery, N.W.; Thielen, P.M.; Costello, M.J. doi  openurl
  Titre Global marine biodiversity in the context of achieving the Aichi Targets: ways forward and addressing data gaps Type Article scientifique
  Année 2019 Publication Revue Abrégée PeerJ  
  Volume 7 Numéro Pages (down) e7221  
  Mots-Clés Aichi targets; assemblages; benefits; Biodiversity tools and pipelines; Biogeography; conservation; coral-reefs; Data standard; Data standards; deep-sea; Discovery; Dissemination; diversity gradient; life; Marine biodiversity; patterns; Prediction; progress; species richness; Stewardship; Stewardship and dissemination; Tools and pipelines  
  Résumé In 2010, the Conference of the Parties of the Convention on Biological Diversity agreed on the Strategic Plan for Biodiversity 2011-2020 in Aichi Prefecture, Japan. As this plan approaches its end, we discussed whether marine biodiversity and prediction studies were nearing the Aichi Targets during the 4th World Conference on Marine Biodiversity held in Montreal, Canada in June 2018. This article summarises the outcome of a five-day group discussion on how global marine biodiversity studies should be focused further to better understand the patterns of biodiversity. We discussed and reviewed seven fundamental biodiversity priorities related to nine Aichi Targets focusing on global biodiversity discovery and predictions to improve and enhance biodiversity data standards (quantity and quality), tools and techniques, spatial and temporal scale framing, and stewardship and dissemination. We discuss how identifying biodiversity knowledge gaps and promoting efforts have and will reduce such gaps, including via the use of new databases, tools and technology, and how these resources could be improved in the future. The group recognised significant progress toward Target 19 in relation to scientific knowledge, but negligible progress with regard to Targets 6 to 13 which aimed to safeguard and reduce human impacts on biodiversity.  
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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 2167-8359 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000493041100001 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2682  
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Auteur Pendleton, L.H.; Ahmadia, G.N.; Browman, H.I.; Thurstan, R.H.; Kaplan, D.M.; Bartolino, V. doi  openurl
  Titre Debating the effectiveness of marine protected areas Introduction Type Article scientifique
  Année 2018 Publication Revue Abrégée ICES J. Mar. Sci.  
  Volume 75 Numéro 3 Pages (down) 1156-1159  
  Mots-Clés Aichi; benefits; conservation; fisheries; management; monitoring; reserves; shortfalls; spillover; sustainable development goals; targets  
  Résumé Increasing the size and number of marine protected areas (MPAs) is widely seen as a way to meet ambitious biodiversity and sustainable development goals. Yet, debate still exists on the effectiveness of MPAs in achieving ecological and societal objectives. Although the literature provides significant evidence of the ecological effects of MPAs within their boundaries, much remains to be learned about the ecological and social effects of MPAs on regional and seascape scales. Key to improving the effectiveness of MPAs, and ensuring that they achieve desired outcomes, will be better monitoring that includes ecological and social data collected inside and outside of MPAs. This can lead to more conclusive evidence about what is working, what is not, and why. Eight authors were asked to write about their experiences with MPA effectiveness. The authors were instructed to clearly define “effectiveness” and discuss the degree to which they felt MPAs had achieved or failed to be effective. Essays were exchanged among authors and each was invited to write a shorter “counterpoint.” The exercise shows that, while experiences are diverse, many authors found common ground regarding the role of MPAs in achieving conservation targets. This exchange of perspectives is intended to promote reflection, analysis, and dialogue as a means for improving MPA design, assessment, and integration with other conservation tools.  
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  Volume de collection Numéro de collection Edition  
  ISSN 1054-3139 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2367  
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Auteur Monsarrat, S.; Pennino, M.G.; Smith, T.D.; Reeves, R.R.; Meynard, C.N.; Kaplan, D.M.; Rodrigues, A.S.L. doi  openurl
  Titre A spatially explicit estimate of the prewhaling abundance of the endangered North Atlantic right whale Type Article scientifique
  Année 2016 Publication Revue Abrégée Conserv. Biol.  
  Volume 30 Numéro 4 Pages (down) 783-791  
  Mots-Clés animals; areas de alimentacion; caza de ballenas; Conservation; Eubalaena; eubalaena-glacialis; feeding grounds; generalized additive modeling; historical baseline; historical data; linea base historica; modelado aditivo generalizado; models; pacific; population size; records; tamano de poblacion; target; whaling  
  Résumé The North Atlantic right whale (NARW) (Eubalaena glacialis) is one of the world's most threatened whales. It came close to extinction after nearly a millennium of exploitation and currently persists as a population of only approximately 500 individuals. Setting appropriate conservation targets for this species requires an understanding of its historical population size, as a baseline for measuring levels of depletion and progress toward recovery. This is made difficult by the scarcity of records over this species' long whaling history. We sought to estimate the preexploitation population size of the North Atlantic right whale and understand how this species was distributed across its range. We used a spatially explicit data set on historical catches of North Pacific right whales (NPRWs) (Eubalaena japonica) to model the relationship between right whale relative density and the environment during the summer feeding season. Assuming the 2 right whale species select similar environments, we projected this model to the North Atlantic to predict how the relative abundance of NARWs varied across their range. We calibrated these relative abundances with estimates of the NPRW total prewhaling population size to obtain high and low estimates for the overall NARW population size prior to exploitation. The model predicted 9,075-21,328 right whales in the North Atlantic. The current NARW population is thus <6% of the historical North Atlantic carrying capacity and has enormous potential for recovery. According to the model, in June-September NARWs concentrated in 2 main feeding areas: east of the Grand Banks of Newfoundland and in the Norwegian Sea. These 2 areas may become important in the future as feeding grounds and may already be used more regularly by this endangered species than is thought. Una Estimacion Espacialmente Explicita de la Abundancia Previa a la Caza de la Ballena Franca del Atlantico Norte en Peligro de Extincion La ballena franca del Atlantico Norte (BFAN) (Eubalaena glacialis) es una de las ballenas mas amenazadas del mundo. Su extincion estuvo proxima despues de casi un milenio de explotacion y actualmente persiste una poblacion de aproximadamente 500 individuos. El establecimiento de objetivos de conservacion apropiados para esta especie requiere del entendimiento del tamano historico de la poblacion como la linea base para la medida de los niveles de disminucion y el progreso hacia la recuperacion. Esto se dificulta por la escasez de registros sobre la larga historia de la caza de esta especie. Buscamos estimar el tamano poblacional previo a la explotacion de la ballena franca del Atlantico Norte y entender como se distribuia esta especie a lo largo de su extension. Usamos un conjunto de datos espacialmente explicitos sobre las capturas historicas de las ballenas francas del Pacifico Norte (BFPN) (Eubalaena japonica) para modelar la relacion entre la densidad relativa de ballenas francas y el ambiente durante la temporada de verano de alimentacion. Cuando asumimos que las dos especies de ballenas francas seleccionan ambientes similares, pudimos proyectar este modelo hacia el Atlantico Norte y asi poder predecir como la abundancia relativa de las BFAN vario a lo largo de su extension. Calibramos estas abundancias relativas con los estimados del tamano poblacional total previo a la caza de las BFPN y asi obtener estimados altos y bajos para el tamano poblacional general de las BFAN previo a la explotacion. El modelo predijo la existencia de 9, 075 – 21, 328 ballenas francas en el Atlantico Norte. La poblacion actual de BFAN es entonces <6 % a la capacidad de carga historica del Atlantico Norte, por lo que tiene un potencial enorme para la recuperacion. De acuerdo al modelo, entre junio y septiembre, las BFAN se concentraron en dos areas de alimentacion principales: al este de los Grandes Bancos de Terranova y en el Mar de Noruega. Estas dos areas pueden volverse importantes en el futuro como sitios de alimentacion y puede que ya sean usadas por esta especie de manera mas regular de lo que se cree. Resumen  
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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 0888-8892 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1641  
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