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Registros recuperados: 16 | |
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Mannocci, Laura; Roberts, Jason J.; Halpin, Patrick N.; Authier, Matthieu; Boisseau, Oliver; Bradai, Mohamed Nejmeddine; Canadas, Ana; Chicote, Carla; David, Lea; Di-meglio, Nathalie; Fortuna, Caterina M; Frantzis, Alexandros; Gazo, Manel; Genov, Tilen; Hammond, Philip S.; Holcer, Drasko; Kaschner, Kristin; Kerem, Dani; Lauriano, Giancarlo; Lewis, Tim; Di Sciara, Giuseppe Notarbartolo; Panigada, Simone; Antonio Raga, Juan; Scheinin, Aviad; Ridoux, Vincent; Vella, Adriana; Vella, Joseph. |
Heterogeneous data collection in the marine environment has led to large gaps in our knowledge of marine species distributions. To fill these gaps, models calibrated on existing data may be used to predict species distributions in unsampled areas, given that available data are sufficiently representative. Our objective was to evaluate the feasibility of mapping cetacean densities across the entire Mediterranean Sea using models calibrated on available survey data and various environmental covariates. We aggregated 302,481 km of line transect survey effort conducted in the Mediterranean Sea within the past 20 years by many organisations. Survey coverage was highly heterogeneous geographically and seasonally: large data gaps were present in the eastern and... |
Tipo: Text |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00626/73789/75004.pdf |
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Guinet, Christophe; Xing, X.; Walker, E; Monestiez, P; Marchand, S.; Picard, Baptiste; Jaud, T.; Authier, Matthieu; Cotte, Cedric; Dragon, Ac; Diamond, E; Antoine, David; Lovell, P.; Blain, Stephane; D'Ortenzio, Fabrizio; Claustre, Herve. |
In situ observation of the marine environment has traditionally relied on ship-based platforms. The obvious consequence is that physical and biogeochemical properties have been dramatically undersampled, especially in the remote Southern Ocean (SO). The difficulty in obtaining in situ data represents the major limitations to our understanding, and interpretation of the coupling between physical forcing and the biogeochemical response. Southern elephant seals (Mirounga leonina) equipped with a new generation of oceanographic sensors can measure ocean structure in regions and seasons rarely observed with traditional oceanographic platforms. Over the last few years, seals have allowed for a considerable increase in temperature and salinity profiles from the... |
Tipo: Text |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00185/29663/28034.pdf |
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Peltier, Hélène; Dabin, Willy; Dars, Cécile; Demaret, Fabien; Doremus, Ghislain; Van Canneyt, Olivier; Laran, Sophie; Mendez-fernadez, Paula; Spitz, Jérôme; Authier, Matthieu; Delphine, Pierre; Ridoux, Vincent. |
Between the 1st of February and the March 31, 2017, 793 stranded cetaceans were found along the French Atlantic coasts. Common dolphins made up 84% of these strandings, and most of these presented evidence of death in fishing gear. The aim of this work is to test an approach that could help identify the fisheries potentially involved in a given stranding event. To do this we examined how the distributions of likely areas of mortality of bycaught dolphins, inferred from carcass drift modelling, coincide with fishing effort statistics of various fleets, generated from the Vessel Monitoring System, in the area over the same dates. Using reverse drift modelling, two main mortality areas were identified. A total of 3690 common dolphins (IC95% [2230; 6900]) were... |
Tipo: Text |
Palavras-chave: Dolphins; Strandings; Bycatch; Fishing effort; Reverse drift; Vessel Monitoring System.. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00592/70392/68473.pdf |
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Duhamel, Erwan; Doray, Mathieu; Huret, Martin; Sanchez, Florence; Authier, Matthieu; Bergot, Patricia. |
The Pelgas15 acoustic survey has been carried out with globally good weather conditions (regular low wind, medium temperatures) for the whole area, from the South of the bay of Biscay to the west of Brittany. The help of commercial vessels (two pairs of pelagic trawlers and a single one) during 18 days provided about 130 valid identification hauls instead of about 50 before 2007 when Thalassa was alone to identify echotraces. Their participation increased the precision of identification of echoes and some double hauls permitted to confirm that results provided by the two types of vessels (R/V and Fishing boats) were comparable and usable for biomass estimate purposes. These commercial vessels participated to the PELGAS survey in a very good spirit of... |
Tipo: Text |
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Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00278/38972/37513.pdf |
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Authier, Matthieu; Doremus, Ghislain; Van Canneyt, Olivier; Boubert, Jean-jacques; Gautier, Gerard; Doray, Mathieu; Duhamel, Erwan; Masse, Jacques; Petitgas, Pierre; Ridoux, Vincent; Spitz, Jerome. |
Conservation has moved from species-centered to ecosystem-based approaches: the Marine Strategy Framework Directive requires the maintenance or restoration of ‘Good Environmental Status’ of all European marine waters. Monitoring biodiversity at the scale of whole ecosystems is salient, but challenging owing to the large spatial scale involved and the large spatio-temporal heterogeneity of marine ecosystems. We capitalized on the integrated ecosystemic PELGAS survey carried out in spring in the Bay of Biscay to document patterns of change in marine megafauna relative abundance at the community level over more than a decade (2004-2016). The relative abundance of the twenty three most frequently sighted species (6 cetaceans and 17 seabirds) was estimated by... |
Tipo: Text |
Palavras-chave: Marine megafauna; Relative abundance; MSFD; Ecosystemic surveys. |
Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00403/51405/51981.pdf |
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Doray, Mathieu; Petitgas, Pierre; Romagnan, Jean-baptiste; Huret, Martin; Duhamel, Erwan; Dupuy, Christine; Spitz, Jérôme; Authier, Matthieu; Berger, Laurent; Doremus, Ghislain; Bourriau, Paul; Grellier, Patrick; Masse, Jacques; Sanchez, Florence. |
The initial focus of the PELGAS integrated survey was to assess the small pelagic fish biomass in the Bay of Biscay in springtime, for fisheries management purposes. Sampling has been extended to produce long-term time-series of spatially-explicit data and indices, describing the main pelagic ecosystem components: hydrology, phytoplankton, mesozooplankton, fish and megafauna. A collaborative analysis of these datasets has brought new insights on the Bay of Biscay pelagic ecosystem summarized here. New results on single ecosystem components include an analysis of water samples to groundtruth the results of an ocean color algorithm aiming at detecting phytoplanktonic coccolithophores. New insights on mesozooplankton spatio-temporal distribution and energy... |
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Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00445/55665/57331.pdf |
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Cox, Samantha; Authier, Matthieu; Orgeret, Florian; Weimerskirch, Henri; Guinet, Christophe. |
High juvenile mortality rates are typical of many long‐lived marine vertebrate predators. Insufficient development in dive and forage ability is considered a key driver of this. However, direct links to survival outcome are sparse, particularly in free‐ranging marine animals that may not return to land. In this study, we conduct exploratory investigations toward early mortality in juvenile southern elephant seals Mirounga leonina. Twenty postweaning pups were equipped with (a) a new‐generation satellite relay data tag, capable of remotely transmitting fine‐scale behavioral movements from accelerometers, and (b) a location transmitting only tag (so that mortality events could be distinguished from device failures). Individuals were followed during their... |
Tipo: Text |
Palavras-chave: Bio-logging; Early life; Foraging ecology; Juvenile mortality; Mirounga leonina; Southern elephant seal; Survival analyses. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00598/71016/69289.pdf |
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Peron, Clara; Gremillet, David; Prudor, Aurelien; Pettex, Emeline; Saraux, Claire; Soriano-redondo, Andrea; Authier, Matthieu; Fort, Jerome. |
Marine Protected Areas (MPAs) are being established across all marine regions but their validity for the conservation of highly mobile marine vertebrates has been questioned. We tested the hypothesis that French coastal MPAs primarily designed for coastal and benthic biota are also beneficial for the conservation of a pelagic seabird, the Vulnerable yelkouan shearwater (Puffinus yelkouan), an endemic species to the Mediterranean Sea. We used a vast spectrum of electronic devices (GPS, temperature-depth-recorders, satellite transmitters and geolocators) and stable isotopic analyses to study the year-round movements and the trophic status of yelkouan shearwaters from the Hyères archipelago (France). In addition we conducted large-scale ship and aircrafts... |
Tipo: Text |
Palavras-chave: Aerial surveys; At-sea observations; Biotelemetry; Conservation biogeography; Spatial planning; Stable isotope analysis. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00163/27460/26393.pdf |
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Doray, Mathieu; Petitgas, Pierre; Huret, Martin; Duhamel, Erwan; Romagnan, Jean-baptiste; Authier, Matthieu; Dupuy, Christine; Spitz, Jerome. |
This paper is a practical contribution to two important debates raised by the implementation of marine ecosystem based management: (i) which ecosystem data can be provided by a fisheries survey optimised for ecosystem monitoring; and (ii) how to combine/select potential indicators to derive useful information on marine ecosystem status and dynamics? A suite of 143 potential indicators, including spatial indices, representing small pelagic fish and their biotic and abiotic environments are presented. Indicators were routinely derived from the PELGAS integrated ecosystem survey conducted in spring in the Bay of Biscay (BoB). The general patterns over time in this suite of 5–16 years, non-stationary time series are characterised using a methodology based on... |
Tipo: Text |
Palavras-chave: Min/max autocorrelation factors; Time correlation; Survey-based indicators; Marine Strategy Framework Directive; Ecosystem variability; Bay of Biscay; Pelagic ecosystem. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00414/52552/53443.pdf |
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Peron, Clara; Authier, Matthieu; Gremillet, David. |
Aim Species distribution models (SDMs) are statistical tools aiming at mapping and predicting species distributions across landscapes. Data acquisition being limited in space and time, SDM are commonly used to predict species distribution in unsampled areas or years, with the expectation that modelled habitat-species relationships will hold across spatial or temporal contexts (i.e., model transferability). This key aspect of habitat modelling has major implications for spatial management, yet it has received limited attention, especially in the dynamic marine realm. Our aims were to test geographical and temporal habitat model transferability and to make recommendations for future population-scale habitat modelling. Location Methods Two contrasted regions... |
Tipo: Text |
Palavras-chave: Biologging; Central-place foragers; Extrapolation; Habitat modelling; Seabirds; Transferability. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00470/58174/75133.pdf |
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Doray, Mathieu; Petitgas, Pierre; Romagnan, Jean-baptiste; Huret, Martin; Duhamel, Erwan; Dupuy, Christine; Spitz, Jerome; Authier, Matthieu; Sanchez, Florence; Berger, Laurent; Doremus, Ghislain; Bourriau, Paul; Grellier, Patrick; Masse, Jacques. |
The Pélagiques Gascogne (PELGAS) integrated survey has been developed by a multidisciplinary team of Ifremer and La Rochelle University scientists since 2000, joined by commercial fishermen in 2007. Its initial focus was to assess the biomass and predict the recruitment success of anchovy in the Bay of Biscay in spring. Taking advantage of the space and versatility of R/V Thalassa II, sampling has been progressively extended to other ecosystem components. PELGAS therefore further developed the second objective of monitoring and studying the dynamic and diverse Biscay pelagic ecosystem in springtime. The PELGAS survey model has allowed for the establishment of a long-term time-series of spatially-explicit data of the Bay of Biscay pelagic ecosystem since... |
Tipo: Text |
Palavras-chave: Pelagic ecosystem; Integrated ecosystem monitoring survey; Marine Strategy Framework Directive; Ecosystem variability; Bay of Biscay; Fishing vessels. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00407/51801/52401.pdf |
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Dessier, Aurelie; Dupuy, Christine; Kerric, Anais; Mornet, Francoise; Authier, Matthieu; Bustamante, Paco; Spitz, Jerome. |
To explore some aspects of mesozooplankton functional diversity, this study quantified energy density during the springtime in the Bay of Biscay both between different species and between different size-classes. Energy densities of copepod species (Centropages typicus, Anomalocera patersoni, Calanus helgolandicus, and Labidocera wollastoni), as well as anchovy eggs (Engraulis encrasicolus) ranged from 0.5 to 6.7 kJ/g wet weight (ww). Considering size-classes, energy densities varied from 0.74 to 1.26 kJ/g ww. Energy density of C. helgolandicus exhibited a spatial pattern with the highest values in the plume of the Gironde estuary. In contrast, no spatial pattern of energy density has been detected considering size-classes. Our results showed that the... |
Tipo: Text |
Palavras-chave: Bay of Biscay; Profitability; Copepods; Prey-predator relationship; Fisheries. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00407/51835/52434.pdf |
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Registros recuperados: 16 | |
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