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Caill-milly, Nathalie; Morandeau, Gilles; Castege, Iker; Sanchez, Florence; Lissardy, Muriel; Chust, Guillem; Borja, Angel; Auby, Isabelle; Lapegue, Sylvie; Prou, Jean; Oger-jeanneret, Helene; Lassalle, Géraldine; Prevost, Etienne; Buoro, Mathieu; Lobry, Jérémy; De Pontual, Helene; De Casamajor, Marie-noelle; Biais, Gerard; D'Elbee, Jean. |
L'exploitation des ressources par la pêche professionnelle et par la conchyliculture repose sur des ressources vivantes sauvages ou domestiquées qui sont présentes dans différents milieux aquatiques depuis les rivières jusqu'au large en mer. L'état de ces populations dépend non seulement des choix d'exploitation au regard des capacités de renouvellement des stocks mais aussi des caractéristiques environnementales qui impactent les différentes phases des cycles biologiques des espèces et jouent donc sur leur bon déroulement. Ces conditions du milieu sont tributaires pour partie des activités anthropiques (qualité et quantité d'eau disponible, obstacles au franchissement, autres perturbations) et peuvent être soumises aux effets du changement climatique. Ce... |
Tipo: Text |
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Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00444/55568/57180.pdf |
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Carbini, Sebastien; Chessel, Anatole; Benzinou, Abdesslam; Fablet, Ronan; Mahe, Kelig; De Pontual, Helene. |
Most of European fish stocks are assessed using age-based models, and otolith interpretation for age estimations costs several million euros annually. In this context, automated ageing systems would provide a mean to 1) standardize ageing, 2) control ageing consistency within and between ageing laboratories 3) build interpreted image data bases ensuring the information conservation and sharing and 4) improve growth studies while reducing the cost of the acquisition of age data. This paper presents a review of different image-based tools for automatic fish ageing from otolith features within the framework of AFISA (EU STREP project on Automated FISh Ageing coordinated by Ifremer). The full automatic ageing process can be divided into three main steps: 1)... |
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Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/00024/13519/10546.pdf |
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Jolivet, Aurelie; Bardeau, J.f.; Fablet, Ronan; Paulet, Y.m.; De Pontual, Helene. |
It is generally accepted that the formation of otolith microstructures (L- and D-zones) and in particular the organic and mineral fractions vary on a daily basis. Raman microspectrometry provides a nondestructive technique that can be used to provide structural information on organic and mineral compounds. We applied it to thin otolith sections of hake in order to address the following issues: (1) the simultaneous characterization of variations in the organic and mineral fractions both in the core area and along successive otolith microstructures; (2) elucidation of significant differences between these fractions; (3) quantification of the effects of etching and staining protocols on otolith structures. The primordium appeared as a punctual area depicting... |
Tipo: Text |
Palavras-chave: Acid etching; Staining; Aragonite; L and D zones; Core. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4355.pdf |
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Jolivet, Aurelie; Fablet, Ronan; Bardeau, Jean-francois; De Pontual, Helene. |
The high spatial resolution analysis of the mineral and organic composition of otoliths using Raman micro-spectrometry involves rigorous protocols for sample preparation previously established for microchemistry and trace elements analyses. These protocols often include otolith embedding in chemically neutral resin (i.e., resins which do not contain, in detectable concentration, elements usually sought in the otoliths). Such embedding may however induce organic contamination. In this paper, Raman micro-spectrometry reveals the presence of organic contamination onto the surface obtained from the use of epoxy resin, specifically Araldite. This contamination level varies depending on otolith structures. Core and checks, known as structural discontinuities,... |
Tipo: Text |
Palavras-chave: Epoxy resin; Otolith composition; Microstructure; Raman spectrometry. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00138/24965/26372.pdf |
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Mille, Tiphaine; Mahe, Kelig; Cachera, Marie; Villanueva, Ching-maria; De Pontual, Helene; Ernande, Bruno. |
Previous studies have shown that food amount influence fish otolith structure, opacity and shape and that diet composition has an effect on otolith chemical composition. This study investigated the potential correlation between diet and otolith shape in 5 wild marine fish species by addressing 4 complementary questions. First, is there a global relationship between diet and otolith shape? Second, which prey categories are involved in this relationship? Third, what are the respective contributions of food quantity and relative composition to diet–otolith shape co-variation? Fourth, is diet energetic composition related to otolith shape? For each species, we investigated how otolith shape varies with diet. These questions were tackled by describing diet in... |
Tipo: Text |
Palavras-chave: Fourier analysis; English Channel; Interspecific; Morphometric analysis; Otolith growth; Saccular otolith; Stomach contents. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00345/45639/45269.pdf |
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Heerah, Karine; Woillez, Mathieu; Fablet, Ronan; Garren, Francois; Martin, Stephane; De Pontual, Helene. |
Background Movement pattern variations are reflective of behavioural switches, likely associated with different life history traits in response to the animals’ abiotic and biotic environment. Detecting these can provide rich information on the underlying processes driving animal movement patterns. However, extracting these signals from movement time series, requires tools that objectively extract, describe and quantify these behaviours. The inference of behavioural modes from movement patterns has been mainly addressed through hidden Markov models. Until now, the metrics implemented in these models did not allow to characterize cyclic patterns directly from the raw time series. To address these challenges, we developed an approach to i) extract new metrics... |
Tipo: Text |
Palavras-chave: Fourier transform; Non negative matrix factorization; Classification; Animal behaviour; European sea bass; Movement ecology; Diurnal and tidal cycles; Biologging; Data storage tags. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00402/51400/51974.pdf |
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De Pontual, Helene; Lalire, Maxime; Fablet, Ronan; Laspougeas, Claire; Garren, Francois; Martin, Stephane; Drogou, Mickael; Woillez, Mathieu. |
From 2010 to 2012, 246 data storage tags were deployed on European seabass in the Iroise Natural Marine Park, a marine protected area (MPA) off west Brittany, France. A return rate of 14.6% associated with long time series of data provided new information on fish ecology (e.g. maximum experienced depth greater than 225 m, temperature range 6.80–21.87°C). Depth and temperature series were used to infer individual migration using an innovative hidden Markov model (HMM) especially developed for seabass geolocation. Reconstructed fish tracks revealed that seabass is a partially migratory species, as individuals exhibited either long-distance migrations towards the Bay of Biscay or the Celtic Sea, or residency behaviour in the Iroise Sea. Fidelity to summer... |
Tipo: Text |
Palavras-chave: Cod; Connectivity; Data Storage Tag (DST); Depth; European sea bass; Dicentrarchus labrax; Geolocation; Partial migration; Spawning site fidelity; Temperature; Vertical movement. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00451/56230/57790.pdf |
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Jolivet, Aurelie; De Pontual, Helene; Garren, Francois; Begout, Marie-laure. |
Controlled experiments were conducted to assess the effects of T-bar and DST tagging on post-release survival and growth of European hake. In this study, two groups of each 30 hake were considered: small fish (SF, average total length: 29.9 cm +/- 2.2 cm) and large fish (LF, average total length: 36.4 cm +/- 2.5 cm). Within each size group, fish were randomly assigned to one of 3 treatment groups: control (C), T-bar tagging referred as conventional tagging (CT) and DST tagging (DST) with dummy tags. After 4 months, the overall survival rate was 35%. Smaller fish were less impacted by the stress induced by handling, anaesthesia and tagging and in the SF group, the survival rates were similar (30%) for CT or DST. Specific growth rates were highly variable... |
Tipo: Text |
Palavras-chave: Merluccius merluccius; Archival tag; Husbandry; Midterm experiment; Captive hake. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00065/17645/15196.pdf |
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Hussy, Karin; Morales-nin, Beatriz; Pineiro Alvarez, Carmen; De Pontual, Helene; Smith, Joanne; Mahe, Kelig; Krumme, Uwe; Songer, Sally; Walther, Yvonne; Rey, Javier. |
This chapter was written during the Workshop on Age Validation of Gadoids (WKAVGS 2013) which was held 6–10 May 2013 at Imedea in Esporles, Mallorca. The terms of reference for the workshop were to: 1. Review information on age estimations, otolith exchanges, workshops, and validation works done so far on the following species: European hake, cod, pollock, saithe, haddock, whiting, and blue whiting; 2. Assemble and compare the results of different validation methods (i.e. marking and recapture, marking the calcified structure, marginal increment analysis, marginal analysis, modal progression analysis, length back-calculation, etc.); 3. Discuss and propose the most appropriate validation methods of age and growth pattern of calcified structures (CS), for... |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00620/73189/72379.pdf |
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Mahe, Kelig; Ider, Djamila; Massaro, Andrea; Hamed, Oussama; Jurado-ruzafa, Alba; Goncalves, Patricia; Anastasopoulou, Aiketerini; Jadaud, Angelique; Mytilineou, Chryssi; Elleboode, Romain; Ramdane, Zohir; Bacha, Mahmoud; Amara, Rachid; De Pontual, Helene; Ernande, Bruno. |
Otolith shape analysis is an efficient fish stock identification tool. However, most applications used left and right otoliths or only one of them arbitrarily chosen without testing for biases resulting from potential directional bilateral asymmetry (DA) in otolith shape, i.e. a unimodal population-level deviation form bilateral symmetry between right and left otolith shapes. In this study, 560 bogues (Boops boops) were sampled from 11 geographical locations from the Canary Islands to the Aegean Sea and elliptical Fourier descriptors were used to describe their otoliths’ shape. First, a significant otolith DA was observed at the global scale with an average amplitude of 2.77%. However, at the scale of sampling locations, DA was not always significant and... |
Tipo: Text |
Palavras-chave: Boops boops; Elliptical Fourier analysis; Mediterranean Sea; Side effect; Stock identification. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00468/57967/60418.pdf |
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Fablet, Ronan; Pecquerie, Laure; De Pontual, Helene; Hoie, Hans; Millner, Richard; Mosegaard, Henrik; Kooijman, Sebastiaan A. L. M.. |
Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous conclusions in fish ecology and fisheries management. Here we develop and validate a numerical model of otolith biomineralization. Based on a general bioenergetic theory, it disentangles the complex interplay between metabolic and temperature effects on... |
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Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00056/16695/14163.pdf |
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Heral, Maurice; Bacher, Cedric; Razet, Daniel; Prou, Jean; Deslous-paoli, Jean-marc; De Pontual, Helene; Raillard, Olivier; Ravail, Brigitte; Maestrini, Serge; Mornet, Francoise; Menesguen, Alain; Sautour, Benoit; Robert, Jean-michel. |
Les termes du contrat passé entre le Fond de la Recherche et de la Technologie et l'IFREMER précisent qu ele programmer a pour objectif une gestion rationnelle du milieu conchylicole avec notamment une mise au point de modèles (voir notification de l'aide en annexe). Un premier modèle appelé modèle global par analogie avec les modèles de pêche met en évidence la limite de la capacité trophique du bassin de Marennes-Oléron pour les huîtres cultivées. Un modèle analytique avec un modèle physique simple permet dans un premier temps de développer un modèle de croissance des huîtres en fonction de la nourriture disponible et d'effectuer des simulations qui confirment l'influence du stock sur les performances de croissance des bivalves. Un troisième approche... |
Tipo: Text |
Palavras-chave: Modélisation; Production; Biomasse; Huîtres creuses; Crassostrea gigas; Capacité biotique; Bassin de Marennes Oléron. |
Ano: 1989 |
URL: http://archimer.ifremer.fr/doc/00048/15904/13332.pdf |
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Pineiro, C; Rey, J; De Pontual, Helene; Goni, R. |
In the first tagging experiment of European hake (Merluccius merluccius L.) conducted off the NW Iberian Peninsula to study hake growth in the wild we released 527 live tagged individuals. The survival rate after capture and tagging was 58%. Mortality during capture was positively correlated with depth of capture and negatively correlated with hake size. Fifteen months after tagging, seven individuals (1.3%) had been recaptured with times at liberty ranging from 29 to 466 days. We provide the first direct measurements of growth rates of Southern stock European hake in the wild and compare them with rates obtained from tagging experiments in other regions and with rates derived from conventional otolith age reading. The mean somatic growth rate of all... |
Tipo: Text |
Palavras-chave: Northeast Atlantic; Age estimation; Tag recapture; Growth rates; European hake. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3525.pdf |
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Bertignac, Michel; De Pontual, Helene. |
The results of a pilot tagging study on hake (Merluccius merluccius), conducted in the northern part of the Bay of Biscay in 2002, indicate that growth rates for this stock may be currently underestimated because of biased estimates of age. The impact that such a bias may have on the stock dynamics and the trends of the key population parameters, recruitment, spawning-stock biomass (SSB), and mortality are investigated. Assuming new growth parameters, a new age-length key is derived and used to produce and catch-at-age data and abundance indices, which are then used to assess the stock. Bias in estimating age affects the absolute levels of fishing mortality and stock biomass estimates, and also impacts the trend in SSB. However, trends in fishing mortality... |
Tipo: Text |
Palavras-chave: Tagging; Stock assessment; Simulation; Management; Growth; European hake; Age estimation. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2824.pdf |
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Registros recuperados: 50 | |
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