Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Ordenar por: RelevânciaAutorTítuloAnoImprime registros no formato resumido
Registros recuperados: 53
Primeira ... 123 ... Última
Imagem não selecionada

Imprime registro no formato completo
A catch curve analysis for east Atlantic and Mediterranean bluefin tuna ArchiMer
Kell, Laurence; Bonhommeau, Sylvain; Fromentin, Jean-marc.
A catch-curve analysis using catch-at-age (CAA) data is performed to evaluate recent changes in selection pattern of the eastern Atlantic and Mediterranean bluefin tuna fishery. This was done in order to detect changes following the implementation of the Recovery Plan.
Tipo: Text Palavras-chave: Bluefin tuna; Catch curves; Management; Selectivity; Stock assessment.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00191/30272/28732.pdf
Imagem não selecionada

Imprime registro no formato completo
Aerial surveys of bluefin tuna in the Western Mediterranean sea: retrospective, prospective, perspective ArchiMer
Bonhommeau, Sylvain; Farrugio, Henri; Poisson, Francois; Fromentin, Jean-marc.
While the current stock status of bluefin tuna (BFT) has been considered as declining, there remain considerable data limitations for its stock assessment in the Mediterranean Sea. The collection of fishery-independent data reveals to be crucial to compensate for the lack of Mediterranean purse seine CPUE indices as well as to overcome a potential halt in the bluefin tuna fishery that would impede the monitoring of the stock and the comparison to reference points. Here we present a retrospective of aerial surveys that have been carried out since 2000. It includes the protocol as well as a retrospective of temporal and spatial distribution of detected schools. We then propose several perspectives that could improve the data collection method itself and the...
Tipo: Text Palavras-chave: Atlantic bluefin tuna; Aerial survey; Index of abundance; Gulf of Lions; Strip transect.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00192/30292/28775.pdf
Imagem não selecionada

Imprime registro no formato completo
Aerial surveys to monitor bluefin tuna abundance and track efficiency of management measures ArchiMer
Bauer, Robert; Bonhommeau, Sylvain; Brisset, Blandine; Fromentin, Jean-marc.
Conservation and management measures for exploited fish species rely on our ability to monitor variations in population abundance. In the case of the eastern stock of Atlantic bluefin tuna (ABFT), recent changes in management policies have strongly affected the reliability of fishery-dependent indicators due to drastic changes in fishing season/area, fisheries selectivity and strategy. However, fishery-independent indices of abundance are rare for large pelagic fish, and obtaining them is often costly and labor intensive. Here, we show that scientific aerial surveys are an appropriate tool for monitoring juvenile bluefin tuna abundance in the Mediterranean. We present an abundance index based on 62 aerial surveys conducted since 2000, using 2 statistical...
Tipo: Text Palavras-chave: Thunnus thynnus; Index of abundance; Fishery-independent; Gulf of Lions; Mediterranean Sea; Strip transect; Distance sampling.
Ano: 2015 URL: https://archimer.ifremer.fr/doc/00281/39192/45096.pdf
Imagem não selecionada

Imprime registro no formato completo
An evaluation of the implications of population structure on the current bluefin tuna advice framework ArchiMer
Kell, Laurence T; Fromentin, Jean-marc; Bonhommeau, Sylvain.
The objectives of the comprehensive ICCAT Atlantic-Wide Research Programme on Bluefin Tuna (GBYP) are to improve data collection, knowledge of key biological and ecological processes, assessment models and management. An important element of which is to develop a robust advice framework consistent with the Precautionary Approach. The current advice framework, which is based upon Virtual Population Analysis, demonstrates how a Management Strategy Evaluation (MSE) framework can be used to evaluate the robustness of management advice to uncertainty about stock structure.
Tipo: Text Palavras-chave: Bluefin; Management Strategy Evaluation; Robustness; Stock structure; VPA.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00192/30277/28740.pdf
Imagem não selecionada

Imprime registro no formato completo
An online tool to easily run stock assessment models, using SS3 and SWO as an example ArchiMer
Nieblas, Anne-elise; Bonhommeau, Sylvain; Imzilen, Taha; Fu, Dan; Fiorellato, Fabio; Barde, Julien.
Tipo: Text
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00403/51439/52008.pdf
Imagem não selecionada

Imprime registro no formato completo
Analytical study of on-chip generations of analog sine-wave based on combined digital signals ArchiMer
David-grignot, Stephane; Lamlih, Achraf; Kerzerho, Vincent; Azaıs, Florence; Soulier, Fabien; Bernard, Serge; Rouyer, Tristan; Bonhommeau, Sylvain.
On-chip sine-wave signal generation is widely covered by literature for Built-In-Self Test (BIST) or biosensor applications. The objective is to generate pure and robust sinewave signal with minimal hardware resources. An attractive solution consists in combining several digital signals to built this analog sine-wave. The objective of this paper is to give an analytical study of various potential solutions based on digitalbased approaches. Thanks to this study, we prove that technique consisting in setting the phase shifts and various amplitude values of the square-wave signals is the most efficient approach. Moreover, this study allows the selection of the best solution in terms of parameters of the square-wave signals to cancel loworder harmonics of the...
Tipo: Text Palavras-chave: Harmonic cancellation; Sine-wave generation; On-chip signal generation.
Ano: 2017 URL: https://archimer.ifremer.fr/doc/00395/50608/55366.pdf
Imagem não selecionada

Imprime registro no formato completo
Assessing causal links in fish stock–recruitment relationships ArchiMer
Pierre, Maud; Rouyer, Tristan; Bonhommeau, Sylvain; Fromentin, Jean-marc.
Understanding whether recruitment fluctuations in fish stock arise from stochastic forcing (e.g. environmental variations) rather than deterministic forces (e.g. intrinsic dynamics) is a long standing question with important applied consequences for fisheries ecology. In particular, the relationship between recruitment, spawning stock biomass and environmental factors is still poorly understood, even though this aspect is crucial for fisheries management. Fisheries data are often short, but arise from complex dynamical systems with a high degree of stochastic forcing, which are difficult to capture through classic modelling approaches. In the present study, recent statistical approaches based on the approximation of the attractors of dynamical systems are...
Tipo: Text Palavras-chave: Causality; Forecasting models; Marine.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00408/51930/52555.pdf
Imagem não selecionada

Imprime registro no formato completo
Attempts to tag large Atlantic bluefin tuna: Development of a methododolgy for future large scale deployments in the Mediterranean ArchiMer
Rouyer, Tristan; Bonhommeau, Sylvain; Giordano, F; Wendling, B; Ellul, S; Ellul, G; Psaila, Ma; Deguara, S; Bernard, S; Kerzerho, V.
Tipo: Text Palavras-chave: Large atlantic bluefin tuna; Mediterranean; Malta; Electronic tagging; Farming cages; Purse seiners.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00484/59609/62626.pdf
Imagem não selecionada

Imprime registro no formato completo
COASTAL MAPPING AND KITESURFING ArchiMer
Barde, J.; Bonhommeau, Sylvain; Chassot, E.; Motah, B..
ollecting data on aquatic biodiversity is very challenging because of the difficulty to access underwater ecosystems. Over the years, field surveys have become easier and cheaper with the development of low cost electronics. Commercial and recreational vessels, including sailboats, can now substantially complement expensive scientific surveys and arrays of observation buoys deployed across the world oceans (Pesant et al., 2015, Karsenti et al., 2011). Meanwhile, a large variety of marine animals such as birds, mammals, and fish have become data collection platforms for both biological and environmental parameters through the advent of archival tags. It becomes obvious that data collection in coastal and high seas will become more popular and that citizen...
Tipo: Text Palavras-chave: Citizen science; Ocean and coastal observing systems; Surfing; Action cameras; Coral reef mapping; Photogrammetry; Deep learning; R.
Ano: 2018 URL: http://archimer.ifremer.fr/doc/00450/56164/57712.pdf
Imagem não selecionada

Imprime registro no formato completo
Co-Occurrence and Habitat Use of Fin Whales, Striped Dolphins and Atlantic Bluefin Tuna in the Northwestern Mediterranean Sea ArchiMer
Bauer, Robert; Fromentin, Jean-marc; Demarcq, Herve; Brisset, Blandine; Bonhommeau, Sylvain.
Different dolphin and tuna species have frequently been reported to aggregate in areas of high frontal activity, sometimes developing close multi-species associations to increase feeding success. Aerial surveys are a common tool to monitor the density and abundance of marine mammals, and have recently become a focus in the search for methods to provide fisheries-independent abundance indicators for tuna stock assessment. In this study, we present first density estimates corrected for availability bias of fin whales (Balaenoptera physalus) and striped dolphins (Stenella coeruleoalba) from the Golf of Lions (GoL), compared with uncorrected estimates of Atlantic bluefin tuna (ABFT; Thunnus thynnus) densities from 8 years of line transect aerial surveys. The...
Tipo: Text
Ano: 2015 URL: https://archimer.ifremer.fr/doc/00284/39481/37969.pdf
Imagem não selecionada

Imprime registro no formato completo
Defining Mediterranean and Black Sea Biogeochemical Subprovinces and Synthetic Ocean Indicators Using Mesoscale Oceanographic Features ArchiMer
Nieblas, Anne-elise; Drushka, Kyla; Reygondeau, Gabriel; Rossi, Vincent; Demarcq, Herve; Dubroca, Laurent; Bonhommeau, Sylvain.
The Mediterranean and Black Seas are semi-enclosed basins characterized by high environmental variability and growing anthropogenic pressure. This has led to an increasing need for a bioregionalization of the oceanic environment at local and regional scales that can be used for managerial applications as a geographical reference. We aim to identify biogeochemical subprovinces within this domain, and develop synthetic indices of the key oceanographic dynamics of each subprovince to quantify baselines from which to assess variability and change. To do this, we compile a data set of 101 months (2002-2010) of a variety of both "classical'' (i.e., sea surface temperature, surface chlorophyll-a, and bathymetry) and "mesoscale'' (i.e., eddy kinetic energy,...
Tipo: Text
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00239/34995/33536.pdf
Imagem não selecionada

Imprime registro no formato completo
Eating up the world's food web and the human trophic level ArchiMer
Bonhommeau, Sylvain; Dubroca, Laurent; Le Pape, Olivier; Barde, Julien; Kaplan, David; Chassot, Emmanuel; Nieblas, Anne-elise.
Trophic levels are critical for synthesizing species' diets, depicting energy pathways, understanding food web dynamics and ecosystem functioning, and monitoring ecosystem health. Specifically, trophic levels describe the position of species in a food web, from primary producers to apex predators (range, 1-5). Small differences in trophic level can reflect large differences in diet. Although trophic levels are among the most basic information collected for animals in ecosystems, a human trophic level (HTL) has never been defined. Here, we find a global HTL of 2.21, i.e., the trophic level of anchoveta. This value has increased with time, consistent with the global trend toward diets higher in meat. National HTLs ranging between 2.04 and 2.57 reflect a...
Tipo: Text Palavras-chave: Human ecology; Nutrition transition; Trophic ecology.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00171/28190/26609.pdf
Imagem não selecionada

Imprime registro no formato completo
Effects of extraction method and storage of dry tissue on marine lipids and fatty acids ArchiMer
Sardenne, Fany; Bodin, Nathalie; Metral, Luisa; Crottier, Anais; Le Grand, Fabienne; Bideau, Antoine; Brisset, Blandine; Bourjea, Jerome; Saraux, Claire; Bonhommeau, Sylvain; Kerzerho, Vincent; Bernard, Serge; Rouyer, Tristan.
Various protocols are currently used to study marine lipids, but there is a growing interest in working on dry samples that are easier to transport. However, reference protocols are still lacking for dry samples. In order to make recommendations on this use, lipid classes and fatty acids (FA) obtained from six analytical protocols using two different tissue states (dry vs wet) and three extraction methods (automat vs manual potter vs leaving the solvent to work on tissue) were compared. Three dry storage modes of tissue (freezer vs gas nitrogen vs dry room) during one and three months were also compared. These comparisons were made on seven marine species with different lipid profiles, including fishes, crustaceans and mollusks. Lipid classes and FA...
Tipo: Text Palavras-chave: Degradation; Freeze-drying; Lyophilization; Lipid class; Marine animal; Protocol.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00467/57898/60189.pdf
Imagem não selecionada

Imprime registro no formato completo
Effects of Stochasticity in Early Life History on Steepness and Population Growth Rate Estimates: An Illustration on Atlantic Bluefin Tuna ArchiMer
Simon, Maximilien; Fromentin, Jean-marc; Bonhommeau, Sylvain; Gaertner, Daniel; Brodziak, Jon; Etienne, Marie-pierre.
The intrinsic population growth rate (r) of the surplus production function used in the biomass dynamic model and the steepness (h) of the stock-recruitment relationship used in age-structured population dynamics models are two key parameters in fish stock assessment. There is generally insufficient information in the data to estimate these parameters that thus have to be constrained. We developed methods to directly estimate the probability distributions of r and h for the Atlantic bluefin tuna (Thunnus thynnus, Scombridae), using all available biological and ecological information. We examined the existing literature to define appropriate probability distributions of key life history parameters associated with intrinsic growth rate and steepness, paying...
Tipo: Text
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00115/22640/20362.pdf
Imagem não selecionada

Imprime registro no formato completo
Estimates of selectivity for the east Atlantic and Mediterranean bluefin tuna from 1970 to 2009 ArchiMer
Fromentin, Jean-marc; Bonhommeau, Sylvain.
This study aims at examining the selectivity patterns among gears and years of the fleets targeting bluefin tuna in the Northeast Atlantic and Mediterranean Sea between 1970 and 2009, using catch curve analyses. The main outputs may be summarized as follow: (i) the general pattern of selectivity has highly varied through time, moving from ages 1-3 to ages 10+ from the 1970s to the 2000s; (ii) this important temporal drift primarily resulted from changes in PS selectivity patterns; (iii) these drastic variations in selectivity among gears and years can affect simple indicators which do not incorporate such information; (iv) the catch-at-age (CAA) matrix seems to be impaired by several inconsistencies that affect primarily the partial CAA of the purse...
Tipo: Text Palavras-chave: Gear selectivity; Stock assessment; Bluefin tuna.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00192/30279/28747.pdf
Imagem não selecionada

Imprime registro no formato completo
Estimates of the mortality and the duration of the trans-Atlantic migration of European eel Anguilla anguilla leptocephali using a particle tracking model ArchiMer
Bonhommeau, Sylvain; Le Pape, O.; Gascuel, D.; Blanke, Bruno; Treguier, Anne-marie; Grima, Nicolas; Vermard, Youen; Castonguay, M.; Rivot, E..
Using Lagrangian simulations, based on circulation models over three different hydroclimatic periods in the last 45 years in the North Atlantic Ocean, the trans-Atlantic migration of the European eel Anguilla anguilla leptocephali was simulated via the passive drift of particles released in the spawning area. Three different behaviours were modelled: drifting at fixed depth, undergoing a vertical migration or choosing the fastest currents. Simulations included mortality hypotheses to estimate a realistic mean migration duration and relative survival of A. anguilla larvae. The mean migration duration was estimated as 21 months and the mortality rate as 3 center dot 8 per year, i.e. < 0 center dot 2% of A. anguilla larvae may typically survive the...
Tipo: Text Palavras-chave: Migration duration; Leptocephalus mortality; Lagrangian modelling.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6614.pdf
Imagem não selecionada

Imprime registro no formato completo
Estimating the productivity of Atlantic bluefin tuna from validated scientific data ArchiMer
Fromentin, Jean-marc; Bonhommeau, Sylvain; Kell, Laurence; Restrepo, Victor.
Estimating the productivity of an exploited marine species is not an easy or a trivial task. In the case of Atlantic bluefin tuna, the productivity can hardly be estimated from the natural mortality rates or the stock recruitment relationships because the former have never been estimated for this species from scientific data, but only “guesstimated”, while the latter remain highly uncertain for both the eastern stock (BFTE) and the western stock (BFTW). To get a better idea of bluefin tuna productivity, we thus applied the approach by Jennings et al. (1998) who proposed a surrogate of r, r’, named the potential rate of population increase. We compared this parameter and age-at-maturity (and to some extent the individual growth curves) of 25 species...
Tipo: Text Palavras-chave: Thunnus thynnus; Population growth rate; Fecundity; Maturity; CITES criteria.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00192/30293/28777.pdf
Imagem não selecionada

Imprime registro no formato completo
Global marine primary production constrains fisheries catches ArchiMer
Chassot, Emmanuel; Bonhommeau, Sylvain; Dulvy, Nicholas K.; Melin, Frederic; Watson, Reg; Gascuel, Didier; Le Pape, Olivier.
Primary production must constrain the amount of fish and invertebrates available to expanding fisheries; however the degree of limitation has only been demonstrated at regional scales to date. Here we show that phytoplanktonic primary production, estimated from an ocean-colour satellite (SeaWiFS), is related to global fisheries catches at the scale of Large Marine Ecosystems, while accounting for temperature and ecological factors such as ecosystem size and type, species richness, animal body size, and the degree and nature of fisheries exploitation. Indeed we show that global fisheries catches since 1950 have been increasingly constrained by the amount of primary production. The primary production appropriated by current global fisheries is 17-112% higher...
Tipo: Text Palavras-chave: Bottom-up; Large Marine Ecosystem; Quantile regression; Sustainable fishing.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00002/11294/7836.pdf
Imagem não selecionada

Imprime registro no formato completo
Global Seabird Response to Forage Fish Depletion-One-Third for the Birds ArchiMer
Cury, Philippe; Boyd, Ian L.; Bonhommeau, Sylvain; Anker-nilssen, Tycho; Crawford, Robert J. M.; Furness, Robert W.; Mills, James A.; Murphy, Eugene J.; Oesterblom, Henrik; Paleczny, Michelle; Piatt, John F.; Roux, Jean-paul; Shannon, Lynne; Sydeman, William J..
Determining the form of key predator-prey relationships is critical for understanding marine ecosystem dynamics. Using a comprehensive global database, we quantified the effect of fluctuations in food abundance on seabird breeding success. We identified a threshold in prey (fish and krill, termed "forage fish") abundance below which seabirds experience consistently reduced and more variable productivity. This response was common to all seven ecosystems and 14 bird species examined within the Atlantic, Pacific, and Southern Oceans. The threshold approximated one-third of the maximum prey biomass observed in long-term studies. This provides an indicator of the minimal forage fish biomass needed to sustain seabird productivity over the long term.
Tipo: Text
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00056/16770/14307.pdf
Imagem não selecionada

Imprime registro no formato completo
Groupe de travail ICCAT d'évaluation de stock du thon rouge Atlantique. Madrid, 4-11 septembre 2012. ArchiMer
Fromentin, Jean-marc; Bonhommeau, Sylvain.
Tipo: Text
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00111/22267/19942.pdf
Registros recuperados: 53
Primeira ... 123 ... Última
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional