Consulta: creatorFacets:"De Pontual, Helene"
Registros recuperados: 50
Data/hora: 06/06/2024 00:36:47

Otolith growth in trout Oncorhynchus mykiss: supply of Ca2+ and Sr2+ to the saccular endolymph
Provedor de dados: 5
Autores: Payan, P; Borelli, G; Priouzeau, F; De Pontual, Helene; Boeuf, G; Mayer Gostan, N.
Kinetic and pharmacological characteristics of Ca2+ fluxes across the saccular epithelium of trout were studied using a perfused isolated inner ear. Ca-45(2+) influx from the Ringer solution to the endolymph was 3-4 nmoles h(-1) mu(-1) endolymph, which corresponds to a global turnover rate of the endolymph calcium of 200% h(-1). Ca2+ entry into the proximal endolymph was faster than into the distal fluid. Net Ca2+ movement across the saccular epithelium depended on the direction and intensity of the chemical gradient of calcium between the Ringer solution and the endolymph. Increasing the calcium concentration in the Ringer solution up to 4.4 mmol l(-1) provoked an accumulation of Ca2+ in both proximal and distal endolymphs, and equilibrium was reached...
Tipo: Text
Palavras-chave: Inner ear; Perfusion; Otolith; Endolymph; Flux; Calcium; Oncorhynchus mykiss; Trout.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/publication-416.pdf

Reconstructing individual shape histories of fish otoliths: A new image-based tool for otolith growth analysis and modeling
Provedor de dados: 5
Autores: Fablet, Ronan; Chessel, Anatole; Carbini, Sebastien; Benzinou, Abdesslam; De Pontual, Helene.
In this paper is presented a novel image processing tool for the extraction of geometric information in otolith images. It relies on the reconstruction of individual otolith shape histories from otolith images. Based on the proposed non-parametric level-set representation of otolith shape history, applications to the extraction of growth axes and ring structures in otolith images are first considered. A second category of applications concern the analysis of 2D otolith growth. The potential of the proposed framework is illustrated on real otolith images for various species (e.g., cod, pollock) and discussed with a particular emphasis on the genericity of the approach and on applications such as otolith shape analysis, multi-proxy otolith analysis, otolith...
Tipo: Text
Palavras-chave: 2D otolith growth; Growth axis extraction; Growth ring extraction; Shape dynamics; Otolith imaging.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6319.pdf

Growth of European hake (Merluccius merluccius) in the Gulf of Lions based on conventional tagging
Provedor de dados: 5
Autores: Mellon-duval, Capucine; De Pontual, Helene; Metral, Luisa; Quemener, Loic.
Growth of European hake was estimated from the results of a conventional tagging study in the Gulf of Lions, the first tagging experiment to have been undertaken on the species in Mediterranean waters. In all, 4277 hake 15–40 cm long were tagged and released on the inshore fishing grounds during spring 2006. The overall recapture rate was 6.5% and times-at-liberty ranged from 1 to 717 d. Growth rate in hake varied with size and sex. The estimated growth parameter (von Bertalanffy k) was estimated as double previously published values based on size frequency distribution in the area. Compared with recent growth parameters derived from the tagging experiments in the Bay of Biscay, k was estimated to be slightly lower in the Gulf of Lions. With this faster...
Tipo: Text
Palavras-chave: Age estimation; European hake; Growth; Mediterranean; Tagging.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00000/11134/11532.pdf

A HMM-based model to geolocate pelagic fish from high-resolution individual temperature and depth histories: European sea bass as a case study
Provedor de dados: 5
Autores: Woillez, Mathieu; Fablet, Ronan; Tran-thanh Ngo,; Lalire, Maxime; Lazure, Pascal; De Pontual, Helene.
Numerous methods have been developed to geolocate fish from data storage tags. Whereas demersal species have been tracked using tide-driven geolocation models, pelagic species which undertake extensive migrations have been mainly tracked using light-based models. Here, we present a new HMM-based model that infers pelagic fish positions from the sole use of high-resolution temperature and depth histories. A key contribution of our framework lies in model parameter inference (diffusion coefficient and noise parameters with respect to the reference geophysical fields—satellite SST and temperatures derived from the MARS3D hydrodynamic model), which improves model robustness. As a case study, we consider long time series of data storage tags (DSTs) deployed on...
Tipo: Text
Palavras-chave: Fish movement; Archival tagging; Migration; Population structure; Hidden Markov Model (HMM); State-space model.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00300/41097/40270.pdf

Daily variations of the saccular endolymph and plasma compositions in the turbot Psetta maxima: relationship with the diurnal rhythm in otolith formation
Provedor de dados: 5
Autores: Edeyer, Anaick; De Pontual, Helene; Payan, P; Troadec, Herve; Severe, Armelle; Mayer-gostan, N.
We studied the circadian variations of the ionic composition ([Na+], [K+], [Cl-]), total CO2 ([tot CO2]), and protein concentration ([protein]) in the plasma and endolymph in the distal and proximal sides of the sacculus in the turbot Psetta maxima. Daily variations in total plasma calcium ([tot Ga]) were also recorded. Significant diurnal fluctuations occurred in most parameters and the spatial heterogeneity of the endolymph composition was maintained throughout a 24 h period. The main parameters implicated in otolith calcification, endolymph [tot CO2] and endolymph [protein], fluctuated diurnally, [tot CO2] was highest and [protein] lowest at night; the relative concentrations were reversed during the day. The inverse, alternating relationship of maximal...
Tipo: Text
Palavras-chave: Daily cycle; Endolymph; Otolith; Chemical composition; Teleost.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/00000/10572/7603.pdf

What can exploratory modelling tell us about the ecobiology of European sea bass (     Dicentrarchus labrax     ): a comprehensive overview
Provedor de dados: 5
Autores: Lopez, Romain; De Pontual, Helene; Bertignac, Michel; Mahevas, Stephanie.
European sea bass, Dicentrarchus labrax, is a highly valuable species in Europe, both for aquaculture in the Mediterranean Sea and for commercial and recreational fisheries in the North East Atlantic Ocean. Subjected to increasing fishing pressure, the wild population has recently experienced significant recruitment fluctuation as well as a northward extension of its distribution area in the North Sea. While the nature of the ecological and/or physiological processes involved remains unresolved, ontogenetic habitat shifts and adult site fidelity could increase the species’ vulnerability to climate change and overfishing. As managers look for expert information to propose management scenarios leading to sustainable exploitation, exploratory modelling...
Tipo: Text
Palavras-chave: Population dynamics; Essential habitats; Connectivity; Bioenergetic modeling; Phenotypic plasticity; Life cycle adaptation.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00341/45258/44699.pdf

Growth of Northwest Iberian juvenile hake estimated by combining sagittal and transversal otolith microstructure analyses
Provedor de dados: 5
Autores: Pineiro, C; Rey, J; De Pontual, Helene; Garcia, A.
Daily growth of Atlantic juvenile hake from Northwest Iberia has been estimated employing a new approach combining analyses of transversal and sagittal sections of the otoliths along the ventral radius. Age of juvenile hake ranging from 3 to 25 cm collected during a spring 2002 survey was estimated. Somatic growth followed a power fit: Fish size (TL) = 3.3254*age(0.7336) (r(2) =0.87, p &lt; 0.001, n = 76). yielding an average individual growth rate of 0.66 mm/day (0.06). The growth model indicates that after a year's life a juvenile can reach 25 cm. Otolith ventral radius ranged from 401 to 1842 mu m and daily increments were between 104 and 387. Fish growth and otolith growth were closely related (r(2) = 0.92 p &lt; 0.001, n = 76). These first results of...
Tipo: Text
Palavras-chave: NW Iberian waters; Seasonal variation; Daily growth; Otolith microstructure; Juvenile hake.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-6111.pdf

TNPC software - Traitement Numérique des Pièces Calcifiées / Numerical Treatment of Calcified Structures : Développement d’un logiciel dédié à l’analyse des pièces calcifiées :
Provedor de dados: 5
Autores: Fave, Sébastien; Crepin, Emeline; Magalhaes, José Ramos; Ogor, Andre; De Pontual, Helene; Mahe, Kelig.
Chaque année, près d’1 million de pièces calcifiées (dont 35 000 en France) sont analysées pour l’évaluation de l’état des ressources marines. De plus, beaucoup de thématiques de recherche nécessitent elles-aussi l’utilisation de ces pièces calcifiées. Ainsi, depuis plus de 20 ans, un partenariat entre la société VSG (Visualization Sciences Group anciennement Noesis) et l’institut de recherche IFREMER (Institut Français de Recherche pour l'Exploitation de la Mer) a permis de développer le logiciel d'analyse d'images dédié aux pièces calcifiées, nommé TNPC (Traitement Numérique des Pièces Calcifiées, www.tnpc.fr). Divers projets de recherche et collaborations en particulier avec l’ENIB (Ecole Nationale des Ingénieurs de Brest) ont été nécessaires pour...
Tipo: Text
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00148/25905/23922.pdf

A comparison of two techniques to discriminate continental origin of Atlantic salmon (Salmo salar L.) off West Greenland
Provedor de dados: 5
Autores: Reddin, David; De Pontual, Helene; Prouzet, Patrick.
Two techniques of stock discrimination both utilizing scales, i. e. termed as classical technique and shape analysis, are compared for discriminating between North American and European Atlantic salmon (Salmo salar L.) caught off West Greenland. Three scales from each of 60 salmon were analyzed: 30 from North American and 30 from European-origin salmon collected from home rivers in 1982. The best results indicated misclassification and error rates of 0% for shape analysis and 5.0% and ± 1.7%, respectively, for the classical technique. A nested ANOVA indicated that variation was greater between scales of salmon of North American and European origin than from several scales from the same salmon. It was concluded that shape analysis with computer-aided...
Tipo: Text
Palavras-chave: Salmo salar; Scalimétrie; Analyse de forme; Discrimination; Salmo salar; Meristics; Shape analysis; Discrimination.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00189/30073/28561.pdf

Contribution of a bioenergetics model to investigate the growth and survival of European seabass in the Bay of Biscay – English Channel area
Provedor de dados: 5
Autores: Dambrine, Chloe; Huret, Martin; Woillez, Mathieu; Pecquerie, Laure; Allal, Francois; Servili, Arianna; De Pontual, Helene.
The European seabass (Dicentrarchus labrax) is a species of particular ecological and economic importance. Stock assessments have recently revealed the worrying state of the “Northern stock”, probably due to overfishing and a series of poor recruitments. The extent to which these poor recruitments are due to environmental variability is difficult to assess, as the processes driving the seabass life cycle are poorly known. Here we investigate how food availability and temperature may affect the growth and survival of wild seabass at the individual scale. To this end, we developed a bioenergetics model based on the Dynamic Energy Budget (DEB) theory. We applied it to seabass population of the Northeast Atlantic region (Bay of Biscay – English Channel area)...
Tipo: Text
Palavras-chave: Dicentrarchus labrax Northeast Atlantic Dynamic Energy Budget theory Growth; Starvation Early-life stages.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00612/72397/71341.pdf

Programme Charente-Marennes-Oléron Volet Maritime
Provedor de dados: 5
Autores: Heral, Maurice; Bacher, Cedric; Razet, Daniel; Prou, Jean; Deslous-paoli, Jean-marc; De Pontual, Helene; Raillard, Olivier; 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: Modèle production; Biomasse; Huître creuse; Crassostrea gigas; Modèle énergétique; Croissance; Modèle multiboîte; Marennes Oléron; Modèle trophique; Marennes Oléron.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/00048/15908/13337.pdf

Analyse des potentielles mesures de gestion du bar
Provedor de dados: 5
Autores: Le Goff, Ronan; Drogou, Mickael; De Pontual, Helene; Talidec, Catherine; Berthou, Patrick; Biseau, Alain.
Une réunion technique a été organisée le 21 mai 2013 par la Commission européenne afin de faire le point sur l’état du stock de bar commun (Dicentrarchus labrax) dans les eaux européennes de l’Atlantique du Nord Est. Cette réunion a conclu que le stock de bar peut être considéré comme dans un état « alarmant », et la Commission a demandé aux Etats membres d’identifier les mesures de gestion qu’ils seraient à même de mettre en place dans les meilleurs délais pour obtenir une diminution des captures de 20%. C’est dans ce contexte que la DPMA a adressé à l’Ifremer la présente saisine, en attendant plus particulièrement de l’Institut :  - de lister les mesures concrètes applicables aux pêcheries françaises et permettant de réduire les captures et donc la...
Tipo: Text
Ano: 2013
URL: https://archimer.ifremer.fr/doc/00165/27657/25827.pdf

Characterising Essential Fish Habitat using spatio‐temporal analysis of fishery data: A case study of the European seabass spawning areas
Provedor de dados: 5
Autores: Dambrine, Chloe; Woillez, Mathieu; Huret, Martin; De Pontual, Helene.
Fish habitats sustain essential functions for fish to complete their life cycle, such as feeding, growing and spawning. Conservation is crucial to maintain fish populations and their exploitation. Since 2013, the spawning stock biomass of the northern stock of European seabass (Dicentrarchus labrax) has been in a worrying state. A series of low recruitments with a persistently high level of fishing has been blamed, raising concerns about the processes involved in seabass reproduction and settlement in nurseries. Here, we characterise seabass spawning areas along the French Atlantic coast using vessel monitoring system (VMS) data. A non‐linear geostatistical approach was applied, from 2008 to 2014, to detect locations where seabass aggregate for spawning....
Tipo: Text
Palavras-chave: Bay of Biscay; Bayesian spatio‐temporal modelling; Dicentrarchus labrax; English Channel; European sea bass; Non‐linear geostatistics; Spawning grounds.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00668/77997/80218.pdf

Aide à l'estimation des stocks d'huîtres en élevage par télédétection basse altitude: étude de faisabilité
Provedor de dados: 5
Autores: De Pontual, Helene.
Existing methods to assess the biomass of reared oyster's stocks are ail based on aerial photographs and field data.  In this study, we propose an automatic processing of the digitized aerial photographs making use of advanced vision tools such as mathematical morphology.  The implemented a1gorithms are described. They give enough convincing results to suggest further developments.  However, this method requires the use of digital images. To this respect, a part of this paper deals with data acquisition problems. We particularly study the feasibility of using airborne video recording system. Such device should give a quite accurate information, easier to process than the classical aerial photographs.
Tipo: Text
Palavras-chave: Huître; Estimation des stocks; Photographie aérienne; Vidéo aéroportée; Analyse d'images numériques; Oysters; Stock assessment; Aerial pholographs; Airborne videography; Digital image processing.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/00105/21669/19247.pdf

Synthèse des informations disponibles sur le Bar : flottilles, captures, marché
Provedor de dados: 5
Autores: Drogou, Mickael; Biseau, Alain; Berthou, Patrick; De Pontual, Helene; Habasque, Jeremie; Le Grand, Christelle; Pitel-roudaut, Mathilde.
Les résultats de ce travail sont établis en France métropolitaine (façades Manche/ Mer du Nord / Atlantique. La structure du rapport comprend d’une part une présentation des données disponibles en 2009 de la pêche professionnelle inscrite au fichier Flotte de Pêche Communautaire (FPC), et d’autre part les résultats de la dernière enquête sur la pêche plaisance réalisée entre 2009 et 2011. En fin de document une présentation des conclusions du groupe de travail du CIEM (WGNEW 2010) est faite en indiquant les données manquantes à collecter pour l’amélioration des diagnostics. Une réflexion concernant les mesures de gestion est ensuite menée à l’aide des résultats disponibles.
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00035/14577/11879.pdf

Manual of Fish Sclerochronology
Provedor de dados: 5
Autores: Panfili, Jacques; De Pontual, Helene; Troadec, Herve; Wrigh, Peter J.
Sclerochronology, the study of calcified structures to reconstruct the past history of living organisms, is central to fish biology and fisheries management. This manual aims to provide an overview of the current theoretical and practical aspects of sclerochronological studies. By providing information on the nature of calcified structures (otoliths, scales, skeleton), their uses in fish research and methods for preparation and examination, the manual constitutes a comprehensive guide for researchers, technicians and students either new to the field or interested in expanding their range of expertise. The enclosed multimedia version (DVD) is supplemented by videos illustrating the main technical procedures with an alternative navigation mode based on...
Tipo: Text
Palavras-chave: Age; Age determination; Biological aging; Chemistry; Growth; Otolith reading; Otoliths; Scale reading; Scales; Skeleton.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/00017/12801/9742.pdf

Characterization and variations of organic parameters in teleost fish endolymph during day-night cycle, starvation and stress conditions
Provedor de dados: 5
Autores: Guibbolini, M; Borelli, G; Mayer Gostan, N; Priouzeau, F; De Pontual, Helene; Allemand, D; Payan, P.
The aim of the present work was to examine the modifications of the organic composition of fish endolymph under environmental conditions (day-night cycle, starvation and Cl-2-Stress) known to modify otolith growth. Endolymph electrophoretic patterns were compared. An antibody raised against the trout otolith organic matrix allowed examining the variations of organic matrix precursors in the endolymph under the above conditions. Western blot analysis showed bands around 60-80 kDa. A 50% decrease of immunolabelling was observed during the night whereas increases were seen after starvation (factor 3) or stress (factor 2) suggesting that these variations could be related to the organic matrix deposit. A factor retarding in vitro CaCO3 crystallization (FRC) was...
Tipo: Text
Palavras-chave: Turbot; Trout; Stress; Starvation; Day night cycle; Organic matrix; Otolith calcification; In vitro crystallization; Endolymph.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1875.pdf

La détermination de l'âge par scalimétrie chez le saumon atlantique (Salmo salar) dans son aire de répartition méridionale : utilisation pratique et difficultés de la méthode
Provedor de dados: 5
Autores: Baglinière, J. L.; Bomassi, P.; Bousquet, B.; Chancerel, F.; De Pontual, Helene; Dumas, J.; Euzenat, G.; Fontenelle, G.; Fournel, F.; Gayou, F.; Luquet, J. F.; Maisse, G.; Martin Ventura, J. A.; Marty, A.; Nihouarn, A.; Porcher, J. P.; Prevost, E.; Prouzet, Patrick; Pustelnik, G.; Richard, A.; Troadec, Herve.
This report confirms interpretation criteria used in scale reading for age determination of Atlantic Salmon in freshwater and in sea water with typical examples. The difficulties for age determination of wild and reared populations by showing atypical examples are presented. Finally some recommandations to a better knowledge of Atlantic salmon population in south distribution area are proposed.
Tipo: Text
Ano: 1985
URL: https://archimer.ifremer.fr/doc/00480/59127/61755.pdf

Elaboration d'un plan de gestion du bar
Provedor de dados: 5
Autores: Drogou, Mickael; Biseau, Alain; Berthou, Patrick; De Pontual, Helene; Habasque, Jeremie; Le Grand, Christelle; Pitel-roudaut, Mathilde.
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00049/16007/14661.pdf

Do environmental conditions (temperature and food composition) affect otolith shape during fish early-juvenile phase? An experimental approach applied to European Seabass (Dicentrarchus labrax)
Provedor de dados: 5
Autores: Mahé, Kelig; Gourtay, Clemence; Bled--defruit, Geoffrey; Chantre, Celina; De Pontual, Helene; Amara, Rachid; Claireaux, Guy; Audet, C.; Zambonino-infante, Jose-luis; Ernande, Bruno.
Otolith shape is an efficient tool for fish stock discrimination. Therefore, it is crucial to identify the environmental parameters that could influence otolith morphogenesis and growth. Current global ocean warming negatively affects the production of polyunsaturated fatty acids (EPA and DHA) by phytoplankton and thus their availability in marine food webs. As EPA and DHA are essential nutrients for most fish species, their deficiency could affect many aspects of fish physiology, notably otolith morphogenesis. The goal of this study was to assess experimentally the combined influences of temperature (T) and dietary polyunsaturated fatty acid (PUFA) content on European seabass (Dicentrarchus labrax) otolith morphogenesis during early life stages. 300...
Tipo: Text
Palavras-chave: N-3 polyunsaturated fatty acids; Otolith shape; Temperature effect; Elliptic Fourier descriptors; Multivariate mixed-effects models; Directional asymmetry.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00588/70054/68017.pdf

Les ressources exploitées par la pêche et la conchyliculture
Provedor de dados: 5
Autores: 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
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00444/55568/57180.pdf

A review of image-based tools for automatic fish ageing from otolith features
Provedor de dados: 5
Autores: 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)...
Tipo: Text
Ano: 2008
URL: http://archimer.ifremer.fr/doc/00024/13519/10546.pdf

Understanding otolith biomineralization processes: new insights into microscale spatial distribution of organic and mineral fractions from Raman microspectrometry
Provedor de dados: 5
Autores: 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

Preparation techniques alter the mineral and organic fractions of fish otoliths: insights using Raman micro-spectrometry
Provedor de dados: 5
Autores: 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

Evidence of underestimation of European hake growth in the Bay of Biscay, and its relationship with bias in the agreed method of age estimation
Provedor de dados: 5
Autores: De Pontual, Helene; Groison, Anne-laure; Pineiro, Carmen; Bertignac, Michel.
In 2002, a pilot experiment on hake tagging was carried out using methodology specifically developed to catch and handle fish in,good condition. By the end of 2005, 36 hake and five tags had been returned to the laboratory (a 3.1% return rate) with a maximum time at liberty of 1066 days. The somatic growth of the recoveries proved to be twofold higher than that expected from published von Bertalanffy growth functions for the species in the Bay of Biscay. The growth underestimation was related to age overestimation, as demonstrated by two independent analyses. The first was based on a blind interpretation of marked otoliths conducted independently by two European experts involved in the routine age estimation of hake. The result shows that the age estimates...
Tipo: Text
Palavras-chave: Tagging; Otolith; Merluccius merluccius; Growth; European hake; Age validation; Age estimation method; Age.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2221.pdf

Numerical analysis of scale morphology to discriminate between atlantic salmon stocks
Provedor de dados: 5
Autores: De Pontual, Helene; Prouzet, Patrick.
The use of an image analysis microsystem with a specially developed software enabled scale image processing, outline extraction and computation of features which are not available in the conventional approach of scale analysis. Those parameters (shape factors, moment invariants and elliptic Fourier coefficients) were introduced into a discriminant analysis process to test their usefulness in stock identification. The method was applied to European stocks originating from Norway (Etne river) and France (Elorn river). The low misclassification rate obtained indicates that this approach is particularly promising.
Tipo: Text
Palavras-chave: Saumon atlantique; Écaille; Analyse numérique; Identification de stocks; Atlantic salmon; Scale; Numerical analysis; Stock identification.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/00189/30066/28554.pdf

Bar commun
Provedor de dados: 5
Autores: De Pontual, Helene; Drogou, Mickael.
Tipo: Text
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00444/55575/57188.pdf

Diet is correlated with otolith shape in marine fish
Provedor de dados: 5
Autores: 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

Coupling spectral analysis and hidden Markov models for the segmentation of behavioural patterns
Provedor de dados: 5
Autores: 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

New insights into behavioural ecology of European seabass off the West Coast of France: implications at local and population scales
Provedor de dados: 5
Autores: 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

Effects of T-bar and DST Tagging on Survival and Growth of European Hake
Provedor de dados: 5
Autores: 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

Unsupervised Bayesian reconstruction of individual life histories from otolith signatures: case study of Sr : Ca transects of European eel (Anguilla anguilla) otoliths
Provedor de dados: 5
Autores: Fablet, Ronan; Daverat, Françoise; De Pontual, Helene.
The reconstruction of individual life histories from chemical otolith measures is stated as an unsupervised signal-processing issue embedded in a Bayesian framework. This computational methodology was applied to a set of 192 European eel (Anguilla anguilla) otoliths. It provided a robust and unsupervised analysis of the individual chronologies of habitat use (either river, estuary, or coastal) from Sr:Ca measures acquired along an otolith growth axis. Links between Sr:Ca values and habitat, age, and season and the likelihood of the transitions from one habitat type to another were modelled. Major movement characteristics such as age at transition between habitats and time spent in each habitat were estimated. As a straightforward output, an unsupervised...
Tipo: Text
Palavras-chave: Otolith microchemistry; Hidden Markov models; Gaussian mixture models; Bayesian labeling; Fish otoliths; Individual life histories.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2533.pdf

Gadoids
Provedor de dados: 5
Autores: 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...
Tipo: Text
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00620/73189/72379.pdf

Otoliths imprinting of sole (Solea solea) from the Bay of Biscay: a tool to discriminate individuals from nursery origins?
Provedor de dados: 5
Autores: De Pontual, Helene; Lagardere, Francoise; Troadec, Herve; Batel, Alain; Desaunay, Yves; Koutsikopoulos, Constantin.
Sole nurseries are located in the main bays and estuaries of the Bay of Biscay, where juveniles from the same stock. concentrate and constitute temporarily isolated groups. This context being favourable for elemental analyses of juvenile otoliths this study has been initiated with the aim of obtaining environmental imprints of the main nurseries of origin of juveniles recruiting to the adult stock, and of evaluating the relative contribution of these nurseries to the stock. The objectives were to compare (i) the otolith elemental imprints obtained by sampling juveniles in the Loire and the Gironde nurseries, and (ii) two multi-element analysis techniques: laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and solution-based ICPMS...
Tipo: Text
Palavras-chave: Recruitment; Juvenile; Estuarine nursery; ICPMS; Trace elements; Otolith; Recrutement; Juvénile; Nourricerie estuarienne; ICPMS; Eléments traces; Otolithe.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-537.pdf

Directional bilateral asymmetry in otolith morphology may affect fish stock discrimination based on otolith shape analysis
Provedor de dados: 5
Autores: 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

Shedding Light on Fish Otolith Biomineralization Using a Bioenergetic Approach
Provedor de dados: 5
Autores: 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...
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00056/16695/14163.pdf

Modélisation des écosystèmes conchylicoles : bassin de Marennes-Oléron - Rapport de fin de Contrat
Provedor de dados: 5
Autores: 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

Tag and recapture of European hake (Merluccius merluccius L.) off the Northwest Iberian Peninsula: First results support fast growth hypothesis
Provedor de dados: 5
Autores: 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

Consequences of bias in age estimation on assessment of the northern stock of European hake (Merluccius merluccius) and on management advice
Provedor de dados: 5
Autores: 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

Sources of otolith morphology variation at the intra-population level: directional asymmetry and diet.
Provedor de dados: 5
Autores: Mille, Tiphaine; Ernande, Bruno; De Pontual, Helene; Villanueva, Ching-maria; Mahe, Kelig.
Tipo: Text
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00339/45052/44455.pdf

Impact de la centrale thermique de Cordemais sur les civelles de Loire. Etude préliminaire sur site et en laboratoire
Provedor de dados: 5
Autores: De Pontual, Helene.
L'importance économique de la civelle en Loire n'est plus à démontrer. Cette région est en effet à la base de 50 % de la production française qui s'élève à 2 000 t environ (ELIE, communication personnelle). La prédation croissante exercéepar l'homme (pêche, construction d'ouvrages industriels, modifications de l'hydrodynamisme des bassins versants, pollutions diverses) conduit à la nécessité d'une gestion de cette ressource. Il semble, dans ce cadre, important de définir le niveau de perturbations des phénomènes migratoires engendrées par le développement actuel et futur des centrales thermiques classiques ou nucléaires. La centrale de Cordemais, actuellement en extension, exerce un impact encore peu étudié sur la montée des civelles (sur ce seul site, des...
Tipo: Text
Ano: 1982
URL: http://archimer.ifremer.fr/doc/00139/25018/23122.pdf

Reconstructing individual food and growth histories from biogenic carbonates
Provedor de dados: 5
Autores: Pecquerie, Laure; Fablet, Ronan; De Pontual, Helene; Bonhommeau, Sylvain; Alunno-bruscia, Marianne; Petitgas, Pierre; Kooijman, Sebastiaan A. L. M.
Environmental conditions experienced by aquatic organisms are archived in biogenic carbonates such as fish otoliths, bivalve shells and coral skeletons. These calcified structures present an accretionary growth and variations in optical properties - color or opacity - that are used to reconstruct time. Full and reliable exploitation of the information extracted from these structures is, however, often limited as the metabolic processes that control their growth and their optical properties are poorly understood. Here, we propose a new modeling framework that couples both the growth of a biogenic carbonate and its optical properties with the metabolism of the organism. The model relies on well-tested properties of Dynamic Energy Budget (DEB) theory. It is...
Tipo: Text
Palavras-chave: Otolith; Calcification; Metabolism; Bioenergetic model; Food reconstruction; Dynamic Energy Budget theory.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00060/17082/14593.pdf

Automatic Fish Ageing (AFISA)
Provedor de dados: 5
Autores: Mahe, Kelig; Parisi, Vincenc; Carbini, Sebastien; Soria, J.a.; Harbitz, A; De Pontual, Helene; Cotano, U; Songer, S; Millner, R; Lewy, P; Gudmundsson, E.f; Fablet, Ronan; Benzinou, Abdesslam.
Most of the fish stocks are assessed using age-based models, however age estimations using otoliths costs several million euros annually. In this context, Automatic Fish Ageing (EU Project) would provide means to standardize ageing among laboratories and build interpreted image databases ensuring the information conservation. Automation improves growth studies while reducing the cost of the acquisition of age data. The whole processing chain from the acquisition of otolith data to the actual ageing issue using pattern recognition or statistical inference has been realised for three case studies : a) Cod (Gadus morhua ; Faeroes, North Sea, North East Arctic) b) Anchovy (Engraulis encrasicolus ; Bay of Biscay) c) Plaice (Pleuronectes platessa, Eastern...
Tipo: Text
Ano: 2009
URL: http://archimer.ifremer.fr/doc/00011/12270/10548.pdf

Projet Bargip. Action Données professionnelles. Rapport final
Provedor de dados: 5
Autores: Drogou, Mickael; Laurec, Alain; Bissery, Claire; Mahevas, Stephanie; Demaneche, Sebastien; Begot, Eric; Weiss, Jerome; De Pontual, Helene; Le Goff, Ronan.
La décroissance des rendements de capture professionnelle de bar européen Dicentrarchus labrax à partir des années 2010-2011 a amené la DPMA à demander à l’Ifremer de proposer un programme de recherche visant à mieux connaitre la biologie de l’espèce et à acquérir des données et connaissances permettant d’envisager sa gestion. Parmi les actions de recherche identifiées comme prioritaires, l’action « Données professionnelles » a compris deux grands volets :  - utilisation des données de captures professionnelles françaises afin de produire des indices annuels d’abondance en bars adultes,  - acquisition de données biologiques (maturité sexuelle principalement et courbe de croissance) sur le bar dans le golfe de Gascogne
Tipo: Text
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00429/54044/55428.pdf

Daily variations of endolymph composition: relationship with the otolith calcification process in trout
Provedor de dados: 5
Autores: Borelli, G; Guibbohni, M; Mayer Gostan, N; Priouzeau, France; De Pontual, Helene; Allemand, D; Puverel, S; Tambutte, E; Payan, P.
Ionic and organic parameters of the otolith calcification process in the trout Oncorhynchus mykiss were analysed in plasma and endolymph over the day:night cycle. Plasma pH remained constant and total CO2 concentration was significantly lower (by 21%) during the day than at night. Calcifying parameters (total CO2, total calcium concentration) were measured in the proximal and distal endolymphs and were unchanged in the latter during the day:night cycle, but fluctuated in the former. Non-collagenous protein and collagen concentrations in endolymph were higher (1.5- and 10-fold, respectively) during the day than at night. As there was no change in total calcium concentration, we propose that Ca2+ increases during the dark period and was maximal by the end of...
Tipo: Text
Palavras-chave: Endolymph; Day night cycle; Calcification; Otolith.
Ano: 2003
URL: https://archimer.ifremer.fr/doc/2003/publication-418.pdf

Projet Bargip. Action Nourriceries. Rapport final
Provedor de dados: 5
Autores: Le Goff, Ronan; Villanueva, Ching-maria; Drogou, Mickael; De Pontual, Helene.
Objectifs du projet : Suite à la chute des rendements des captures professionnelles de bar européen Dicentrarchus labrax à partir des années 2010-2011, la DPMA  a demandé à l’Ifremer de mettre en place un programme de recherche visant à mieux connaitre la biologie de l’espèce et à acquérir des données permettant d’envisager sa gestion. Parmi les actions de recherche identifiées comme prioritaires, l’une portait sur les nourriceries de l’espèce. Il s’est agi au cours du projet de :  - caractériser les habitats préférentiels des juvéniles de bar en travaillant sur deux nourriceries pilotes : estuaire de l’Aulne en rade de Brest et estuaire de la Loire,  - développer un protocole (engin, méthodes, stratégie) d’échantillonnage permettant de produire des...
Tipo: Text
Palavras-chave: Bar européen; Dicentrarchus labrax; Nourriceries; Indices d’abondance; Habitats; Protocole d’échantillonnage au moyen d’un chalut GOV; Test de marquage conventionnel; Rade de Brest; Estuaire de l’Aulne; Estuaire de la Loire.; European Sea Bass; Dicentrarchux labrax; Nurseries; Abundance indexes; Habitats; Sampling protocol with a high opening trawling net; Conventional tagging experimentation; Bay of Brest; Aulne estuary; Loire estuary.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00379/48987/49408.pdf

Importance and future of individual markers for the ecosystem approach to fisheries
Provedor de dados: 5
Autores: Fromentin, Jean-marc; Ernande, Bruno; Fablet, Ronan; De Pontual, Helene.
The use of genetic, biochemical and electronic markers in population biology and ecology has been growing tremendously during the last two decades. The first part of this paper aims at reviewing the main principles and advances of these individual markers through a few key applications on exploited marine fish populations. The second part is more prospective and investigates some possibilities that could arise in the near future through: (i) the development of new markers, (ii) the combination of different markers and (iii) the combination of quantitative approaches-whether classical or new-with individual markers. It is finally stressed how crucial individual markers will be to unravel the biocomplexity of wild fish populations and the key role they...
Tipo: Text
Palavras-chave: Genetic marker; Biochemical marker; Electronic tag; Otolith; Isotope; Population structure; Statistical and mechanistic model; Fisheries.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/00000/11163/7522.pdf

Are hake otolith macrostructures randomly deposited? Insights from an unsupervised statistical and quantitative approach applied to Mediterranean hake otoliths
Provedor de dados: 5
Autores: Courbin, Nicolas; Fablet, Ronan; Mellon-duval, Capucine; De Pontual, Helene.
Individual fish age data are crucial to fish stock assessment, so their accuracy and precision are vital. The acquisition of age data most often relies on interpreting fish otoliths, a complex task in which expert subjectivity increases with the complexity of the structural patterns of the otoliths. The question arises for certain fish species (e.g. hake, Merluccius merluccius) whether the deposition of otolith macrostructures is meaningful for age estimation. A quantitative method based on the evaluation of otolith similarity in terms of structural patterns is presented to investigate this issue. It relies on the determination of a typology of otolith macrostructures from an unsupervised statistical analysis of the distributions of their characteristics....
Tipo: Text
Palavras-chave: Quality control; Otolith; Merluccius merluccius; Growth; Age estimation method; Age.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2678.pdf

Comparison of 0- and 2-group otolith elemental signatures to discriminate Solea solea nurseries in the bay of biscay
Provedor de dados: 5
Autores: Durieux, Eric D. H.; Labonne, Maylis; Begout, Marie-laure; De Pontual, Helene.
The common sole Solea solea (L.) is a commercially important and widely distributed flatfish of the North-East Atlantic. For the Bay of Biscay stock, sole nurseries display differences in terms of quantity and quality. In fine the measure of the quality of a habitat for juveniles of a particular species is expressed by the contribution to the recruitment into the adult population. Understanding this connectivity between juvenile and adult habitats, i.e. evaluating the contribution of each nursery to a single adult stock appears essential in terms of stock management. However, this critical link is still missing for the Bay of Biscay sole stock. Determining if nurseries could be discriminated using otolith elemental composition analysis constitutes the...
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00073/18377/15949.pdf

SYstème de BIOmétrie Larvaire de bivalves par analyse d'images
Provedor de dados: 5
Autores: De Pontual, Helene.
SYBIOL, SYstem of BIOmetry of Larvae by image analysis, has been designed for measuring larvae of bivalves in a semi automatic way. The main interest of this tool is to provide more information with the extraction of parameters such as area or equivalent diameter. Our purposes are to describe and evaluate the system which is now operational and used in routine in the mollusc hatchery of Argenton.
Tipo: Text
Palavras-chave: Croissance; Elevages larvaires; Mollusques; Analyse d'images; Growth; Larval rearing; Molluscs; Image analysis.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00451/56302/57890.pdf