Thèses sur le sujet « Paléoenvironnement – Kerguelen, Îles (Terres australes et antarctiques françaises) »
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Consultez les 44 meilleures thèses pour votre recherche sur le sujet « Paléoenvironnement – Kerguelen, Îles (Terres australes et antarctiques françaises) ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Parcourez les thèses sur diverses disciplines et organisez correctement votre bibliographie.
Herlédan, Maïwenn. « Biodiversité des amibes à thèque et environnements de l'archipel de Kerguelen : caractérisation actuelle et évolution récente sous contrainte climatique ». Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILR002.
The objective of this PhD is to describe the current diversity of testate amoebae on the Kerguelen archipelago depending on climate and environmental context and to understand the recent evolution of the last 260 years by a paleoenvironmental approach combining microscopic observations, sedimentology and geochemistry. Located at the polar front in the sub-Antarctic zone, the Kerguelen archipelago is subject to extreme wind and precipitation conditions while being preserved from direct anthropic impacts. This makes it an ideal natural environment to study the impact of global climate change on the environment.Two scientific campaigns on the Kerguelen archipelago in 2019 and 2021 have allowed us to collect samples of current plants (mainly bryophytes and azorelles), underlying soils and soil cores. The samples studied were selected to reflect the geographical and geological diversity of the archipelago, in terms of rainfall (west-east contrast), sedimentary nature (organic soil, alluvial sediments, etc.. ) and petrographic context (basalts - phonolites). Optical observations of the testate amoebae communities growing in the plant samples (101 samples) have allowed us to build a new database of testate amoebae in the archipelago. Sedimentological and geochemical analyses (water content, elemental and isotopic analyses, mineralogy) were carried out in parallel on 485 soil samples in order to characterize the environmental parameters.This work has allowed to update and complete the 1981 database of 50 species with the description of 107 species of testate amoebae. Sedimentological analyses of soils revealed significant differences in terms of weathering between the western and eastern parts of the archipelago, reflecting contrasting rainfall patterns. This trend is also reflected in the testate amoebae assemblages whose diversity, variable according to the type of environment, is much greater in the west. The coupling of these different observations has made it possible to highlight the ecological affinities of certain species with specific environments, which depend mainly on the water content of the sediment, the type of environment and the vegetation, thus allowing the definition of indicator species. The use of this approach to reconstruct recent paleoenvironments from the different soil cores has allowed us to highlight local changes in the environment, which could be attributable to recent climate change. This study demonstrates the relevance of testate amoebae not only as an environmental indicator but also for tracing the recent evolution of paleoenvironmental conditions under climatic constraints
Gautier, Isabelle. « Les Basaltes des îles Kerguelen (Terres australes et antarctiques françaises) ». Paris 6, 1987. http://www.theses.fr/1987PA066171.
Imbaud, Pierre. « Dynamique saisonnière d'une communauté bactérioplanctonique subantarctique (Archipel de Kerguelen) ». Lyon 1, 1987. http://www.theses.fr/1987LYO11752.
Chapuy, Bruno. « Les smectites des sédiments marins quaternaires du plateau de Kerguelen-Heard (Océan indien austral) : nature et origines : relation avec l'environnement volcanique des îles Kerguelen, littoral et marin ». Bordeaux 1, 1988. http://www.theses.fr/1988BOR10529.
Plenier, Guillaume. « Fluctuations du champ paléomagnétique terrestre enregistrées par les laves de l'Archipel des Kerguelen (partie australe de l'Océan Indien) et détermination de leur direction de mise en place ». Montpellier 2, 2002. http://www.theses.fr/2002MON20186.
Leyrit, Hervé. « Kerguelen : cartographie et magmatologie des presqu'iles Jeanne d'Arc et Ronarc'h ». Paris 11, 1992. http://www.theses.fr/1992PA112257.
Boussès, Patrick. « Biologie de population d'un vértébré phytophage introduit, le lapin (Oryctolagus cuniculus) dans les îles subantarctiques de Kerguelen ». Rennes 1, 1991. http://www.theses.fr/1991REN10128.
Gendron-Badou, Aïcha. « Paléopositions du front polaire antarctique au cours du Pléistocène dans la région de Kerguelen (Océan Indien austral) ». Paris, Muséum national d'histoire naturelle, 1996. http://www.theses.fr/1996MNHN0024.
Koubbi, Philippe. « L'ichtyoplancton de la partie indienne de la province kerguelenienne (bassin de Crozet et plateau de Kerguelen) : identification, distribution spatio-temporelle et stratégies de développement larvaire ». Paris 6, 1992. http://www.theses.fr/1992PA066204.
Moine, Bertrand. « Les enclaves ultramifiques-mafiques riches en volatils de Kerguelen (TAAF, Océan Indien), transferts de fluides et métasomatisme mantellique en contexte intraplaque océanique : étude pétrologique, géochimique (éléments en traces par LAM-ICP-MS) et isotopique (O, C, H) ». Saint-Etienne, 2000. http://www.theses.fr/2000STET4002.
Delpech, Guillaume. « Etude des enclaves ultramafiques des Iles Kerguelen : caractérisation du métasomatisme sous un plateau océanique ». Saint-Etienne, 2004. http://www.theses.fr/2004STET4007.
Petrological and geochemical studies in basalt-hosted peridotite xenoliths from Kerguelen Islands (Indian Ocean) indicate that the oceanic lithosphere formed in two steps ; i) a high degree partial melting episode related to the superposition of the southeast indian ridge and the Kerguelen plume ; ii) the percolation of important volumes of alkaline magmas at the scale of the Archipelago. Locally, peridotite-magma reactions produce small volumes of carbonate-rich melts. The study of chalcophile and siderophile elements (PGE, Au, Cu, S, Se, Re) indicate the budget of those elements in peridotites varies with the type of metasomatism, producing either a depletion or an enrichment. The 87Sr/86Sr isotopic compositions in clinopyroxenes evidence two types of mantle benetah the Archipelago. The western part comprises the oldest xenoliths localities (~30 Ma) and bears the imprint of metasomatism requiring a depleted component. The Sr isotopic compositions in the eastern xenolith localities (<25 Ma) are attributed to the global imprint left by magmas from the Kerguelen plume. Some peridotites have 187Os/188Os isotopic compositions that are simiular to those of peridotites in continental cratonic areas, indicating the presence of old subcontinental lithospheric material under the Archipelago, probably incorporated during the Gondwana breakup. Alternatively, the Os isotopic compositions of some carbonated peridotites indicate the participation of a recycled component associated to the Kerguelen plume
Chevet, June. « Intrusive basaltic rocks and associated mafic / ultramafic cumulates from the thickened oceanic crust of the Kerguelen archipelago ». Saint-Etienne, 2009. http://www.theses.fr/2009STET4012.
Cette étude présente des données minéralogiques, géochimiques et isotopiques de roches intrusives et de xénolithes mafiques / ultramafiques représentant différents niveaux de la croûte épaissie de l'Archipel de Kerguelen. Ces données montrent que les roches intrusives ont une origine similaire à celle des basaltes de l'Archipel. Elles ont subi des processus de cristallisation fractionnée surimposés à une évolution magmatique (affinité tholéiitique-transitionnnelle à alacaline). Les xénolithes mafiques / ultramafiques sont des cumulats de niveaux profonds et superficiels. Ils ont principalement cristallisés à partir de magmas tholéiitique-transitionnels mais certains ont pu cristalliser à partir de magmas alcalins. Certains cumulats tholéiitique-transitionnels ont subi une infiltration secondaire fortement alcaline. Les isotopes de l'oxygène montrent que certaines roches intrusives ont subi des re-équilibrations à basses températures cependant les cpx des roches intrusives et cumulats ont gardé une signature mantellique. L'évolution depuis un magmatisme tholéiitique-transitionnel à un magmatisme alcalin peut s'expliquer par une diminution du degré de fusion partielle couplée à une diminution de composition en isotopes radiogéniques : (1) un mélange entre une composante type SEIR et une composante Plume de Kerguelen, (2) une composante Plume de Kerguelen seule et (3) une composante qui pourrait être attribuée à la présence d'une composante continentale, à des hétérogénéités dans le plume ou enfin à la présence d'anciens fragments de manteau subcontinental lithosphérique
Réale, Denis. « Effets des contraintes environnementales sur la reproduction des femelles de deux populations d'ovins, le mouflon (Ovis musimon) et le mouton (Ovis aries), introduits dans l'archipel de Kerguelen ». Rennes 1, 1996. http://www.theses.fr/1996REN10123.
Mespoulhe, Philippe. « Morphologie d'un échinidé irrégulier subantarctique de l'archipel des Kerguelen : ontogenèse, dimorphisme sexuel et variabilité ». Dijon, 1992. http://www.theses.fr/1992DIJOS057.
Gérard, Karin. « Phylogéographie et génétique des populations des Mytilidae de l'archipel des Kerguelen : influence de l'environnement austral sur les capacités de dispersions ». Aix-Marseille 2, 2008. http://theses.univ-amu.fr.lama.univ-amu.fr/2008AIX22061.pdf.
The Southern Ocean connects the coasts in the cold temperate zone of the Southern Hemisphere. This ocean is characterized by several oceanic fronts, and mostly by the Antarctic Circumpolar Current. The establishment of this current was allowed by the opening of the Drake Passage between South America and the Antarctic Peninsula. It enhanced the dispersal of a lot of marine invertebrate species across the Southern Ocean. The Kerguelen Archipelago is located in the Southern Indian Ocean. It is isolated from every continent by bathymetric, geographic and oceanic barriers. Two mytilid species occur in Kerguelen, Aulacomya ater regia et Mytilus desolationis. Both species have a several weeks planktonic larval phase potentially providing high dispersal abilities. Infering the genetic origin of their Kerguelen populations allows to precise their effective isolation from the other southern populations. The effect of the environment on the dispersal abilities was also analyzed at the Southern Ocean scale and, for Mytilus only, at the scale of the Kerguelen Archipelago. The genus Aulacomya is restricted to the Southern Ocean. The most ancient fossils occur in the the Antarctic Penincula and Patagonia in mid Eocene layers. Nowadays, two species are recognized in the genus Aulacomya: A. Maoriana in New Zealand and A. Ater in South America and South Africa and also the subspecies A. Ater regia in Kerguelen. The analysis of five samples at the mitochondrial DNA marker 16S (16S mtDNA), reveals three genetically differentiated entities: one corresponds to New Zealand samples and diverges from the others two entities which represent, in the one hand, South African samples and in the other hand, samples from Patagonia and Kerguelen. The genetic proximity between the latter two regions may be explained by a gene flow allowed by the circumpolar current. The mussels from the Mytilus edulis complex of species are antitropically distributed. The origin of the genus is probably located in the North Pacific, 4 millions years ago. In the Northern Hemisphere, three taxa are genetically differentiated (M. Edulis, M. Galloprovincialis, M. Trossulus), despite the presence of hybrid zones of hybridization. In the Southern Hemisphere, based on morphological characters and nuclear DNA data, the populations from South America and Kerguelen were attributed to M. Edulis, and those from Australasia to M. Galloprovincialis, thus suggesting two independent trans-equatorial migrations. Here, the analysis of the mtDNA loci COI and 16S, revealed the existence of one southern lineage separated in three subclades (South America and Kerguelen ; Tasmania ; New Zealand), thus suggesting only one trans-equatorial migration. In order to reconcile the discordent nuclear and mitochondrial data, two scenarios are discussed. The genetic differentiation of Mytilus mussels from Kerguelen Archipelago, is then analysed with the mtDNA marker (COI) and two nuclear DNA loci, an intron supposed selectively neutral and an exon. Only the exon revealed a genetic differentiation between samples located in north, south coasts and in the Gulf of Morbihan (characterized by a particular hydrology). At the scale of the archipelago, the genetic differentiation can be linked to hydrology. However, the association between differentiation at small scale and several qualitative environmental variables, reveals the influence of the geographic location, and to a lesser extent, of the wave exposure at the sampling site. In both mytilid genus, mitochondrial genealogies proved the common origin of populations from Patagonia and Kerguelen, suggesting the influence of the circumpolar current on the dispersal abilities. However, the population differentiation is not always due to marine currents, thus suggesting the importance of selection and local adaptation
Verdier, Olivier. « Champs géothermiques et zéolitisation des îles Kerguelen : implications géologiques (Terres australes et antarctiques françaises, océan indien austral) ». Paris 6, 1989. http://www.theses.fr/1989PA066503.
Bost, Charles-André. « Variation spatio-temporelle des ressources marines et stratégies adaptatives des oiseaux côtiers : le cas du manchot papou (Pygoscelis papua) ». Paris 11, 1991. http://www.theses.fr/1991PA112201.
Poulin, Elie. « Signification adaptative et conséquences évolutives de l'incubation chez un invertébré marin benthique subantarctique, Abatus cordatus (Verrill, 1876) (Echinodermata : Spatangoida) ». Montpellier 2, 1996. http://www.theses.fr/1996MON20099.
Bouvy, Marc. « Rôle des microflores bactériennes dans les transferts d'énergie au sein d'une station intertidale subantarctique (archipel de Kerguelen) ». Lyon 1, 1985. http://www.theses.fr/1985LYO11695.
Doucet, Sonia. « Interactions rides-points chauds et originalité du chimisme de l'océan Indien. Apport de l'étude géochimique et isotopique (Hf-Pb-Sr-Nd) des îles Kerguelen et Amsterdam et St. Paul ». Saint-Etienne, 2002. http://www.theses.fr/2002STET4012.
Two mantles plumes are responsible for the genesis of the Kerguelen and of the Amsterdam and St. Paul (ASP) islands. The Kerguelen Archipelago began to form 40 Ma ago on the Southeast-Indian Ridge (SEIR), a situation comparable with that of Iceland and of the ASP islands today, then evolved toward its intraplate situation. The interactions of these three islands with the SEIR are recorded for example, in the geochemistry of basalts of the Kerguelen Archipelago and of the ASP islands. Their Hf-Pb-Sr-Nd isotopic composition confirm the decreasing involvment of the SEIR-MORB source as the SEIR migrated towards the Northeast compared to the Kerguelen Archipelago, and suggest the local heterogeneity of the Kerguelen plume. Bsalts from St Paul require a mixture involving the deep source of the Kerguelen plume. This suggests that the two ASP and Kerguelen mantle plumes rose independently through the mantle from a common DUPAL source located at the base of the Indian mantle
Bocher, Pierrick. « Ecologie alimentaire et interactions prédateurs-proies au sein d'une communauté de pétrels planctonophages des Iles Kerguelen ». La Rochelle, 2001. http://www.theses.fr/2001LAROS064.
Kaeuffer, Renaud. « Dynamique de la diversité génétique et effets fondateurs : l’exemple du mouflon (Ovis aries) de Kerguelen ». Lyon 1, 2007. http://www.theses.fr/2007LYO10329.
My PhD focused on the study of the dynamics of genetic diversity in a population of mouflons (Ovis aries) which was founded in 1957 by a single pair of individuals on an island in the Kerguelen archipelago (Indian Ocean). During this study, I first followed the variation in heterozygosity (He), from the foundation of the population through to 2003. I showed that the actual observed He value is higher than expected by neutral population genetics models. Our results, suggest that this strong He may be due to selection (Kaeuffer et al. Proc R Soc B 2007). Next, to measure genetic drift, I estimated the effective mouflon population size. Despite unfavourable conditions including cyclic demography and a promiscuous mating system with strong competition between males, drift was found to be limited. These results suggest that variation in population density diminish competition between males, and therefore most males contribute to reproduction, limiting the loss of genetic diversity (Kaeuffer et al. Mol Ecol 2007). The genetic structure of the populations can also influence He dynamics. Using a very popular population genetic software, I detected genetic structure in the mouflon population. However this structure appears to have little biological relevance and may be due to characteristics of the genetic markers used (Kaeuffer et al. Heredity 2007). Finally I measured the effects of genetic diversity on individual fitness. I showed a negative effect of homozygosity and parasitic load on the physical condition of female mouflons. However, contrary to expectation, inbred females were found to have the highest probability of twining (Kaeuffer et al. Submitted)
Cook, Timothée. « Ecologie des oiseaux plongeurs (Phalacrocorax spp. ) : réponses écophysiologiques, comportementales et sexuelles aux variations de l'environnement ». La Rochelle, 2008. http://www.theses.fr/2008LAROS230.
The first goal of this thesis was to understand what are the ecophysiological and behavioural adaptations of diving birds to the constraints of diving, by studying the blue-eyed shags from Crozet (Phalacrocorax melanogenis) and Kerguelen (P. Verrucosus). Both species made the longest and the deepest dives in the cormorant family, while foraging in a 3 - 7°c seawater for daily periods lasting 5 - 10 hours. It is likely that these performances are possible because of the use of a hypometabolism. When resource distribution allowed it, these shags used diving strategies close to optimality, submerging for periods facilitating a rapid surface reloading of oxygen reserves. Eventually, the study of the depth of neutral buoyancy showed these birds probably adjusted their respiratory air volumes to dive depth, as a mean for saving oxygen. The second goal of this thesis was to study the possible links between blue-eyed shag sexual dimorphism (smaller females) and the ecology. An important sexual segregation was found (females diving to a shallower depth compared to males and catching smaller fish), probably related to the sexual dimorphism. The intensity of the sexual dimorphism varied from one colony to the next and increased locally when the difference in mean dive depth between the sexes increased. This plasticity of the sexual dimorphism could help the species to adjust to the distribution of resource, while reducing intraspecific competition
Ouisse, Tiphaine. « Phenotypic and genetic characterisation of the carabid beetle Merizodus soledadinus along its invasion gradient at the subantartic Kerguelen Islands ». Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1B017/document.
Global trade and human movements increase the likelihood of long-distance transportation of propagules and their subsequent introduction into new geographic regions. In some instances, newly established species can become dominant in invaded communities, at the expense of native species. Besides threatening invaded communities and ecosystem functions, biological invasions constitute natural experiments that allow to study eco-evolutionary processes in real time, including the occurrence of new biotic interactions affecting community composition, rapid adaptation to novel environmental conditions, or dispersal evolution at range margins. Because of their impoverished native communities, oceanic islands’ ecosystems are particularly sensitive to biological invasions, and the French subantarctic islands are no exception. For instance, the flightless predatory carabid beetle Merizodus soledadinus is native from the southern tip of South America, and has been accidentally introduced to the Kerguelen Islands in 1913. In the present work, we aimed at understanding the main mechanisms underlying the invasive success of this insect at the Kerguelen Islands. Using a vast array of methodologies, ecological features of M. soledadinus were investigated with analytical procedures scaling from population to molecule through the individual level. Genetic investigations support the historically-based hypothesis of a single introduction event at a unique location of the Kerguelen Islands. No genetic structure was observed among individuals sampled from different populations along the invasion gradient. We tested the hypothesis of spatial sorting of populations during range expansion, by exploring phenotypic changes among individuals sampled along the invasion gradient. The measured phenotypic traits revealed major differentiation of adults according to the residence time of their populations, confirming the occurrence of spatial sorting of populations during geographic expansion. We also demonstrated that the geographic expansion of M. soledadinus, and microhabitat selection, are primarily governed by the availability of water resources, as suggested by the high sensitivity to water stress of adults of this ground beetle. In parallel, colonisation of altitudinal habitats is governed by thermal conditions, which seem to be physiologically constraining from 200m asl onwards. As the altitudinal distribution of M. soledadinus still extends, we concluded that ongoing climatic changes play a pivotal role in this expansion. Finally, adults of this ground beetle are long-lived and active year-round. The ecological knowledge of M. soledadinus characteristics and spatial expansion dynamics suggest that the colonisation process of the Kerguelen archipelago by this species will continue. Altogether, these data could be used for parametrising range expansion models that would delineate dispersal pathways and expansion rates, in the objective to assist stakeholders’ management decisions
Laparie, Mathieu. « Succès invasif de deux insectes introduits aux Îles Kerguelen : le rôle des ajustements morphologiques et écophysiologiques aux nouvelles conditions environnementales ». Phd thesis, Université Rennes 1, 2011. http://tel.archives-ouvertes.fr/tel-00670533.
Perraudeau, Yves. « Approche de la problématique du redéploiement de la grande pêche industrielle française : l'exemple des îles Kerguelen ». Paris 1, 1986. http://www.theses.fr/1986PA010062.
Jaffal, Ali. « Eco-physiologie des réponses aux stress chimiques chez le poisson en milieu naturel : cas des salmonidés des îles Kerguelen ». Thesis, Reims, 2011. http://www.theses.fr/2011REIMS001/document.
The Kerguelen Islands (40°S, 70°E) contain freshwater ecosystems among the most isolated from human activities in the world. The aim of this work was to study the bio-ecological factors influencing levels of chemical bioaccumulation in Kergueln salmonids tissue (brown trout, Salmo trutta and brook trout, Salvelinus fontinalis) and their potential toxic effects. Our work demonstrated that the hepatic and muscular Cu and Cd levels, and also, the muscular PCB levels were hight and similar to those of salmonids from impacted areas. Moreover, differences in contamination according to species, season and morphotype (lake, river and base) were noted. Histological analysis of trouts livers showed clear damage of liver (fibrosis, infiltration of immune cells, development centers mélanomacrophagiques) and of hepatocytes (necrosis, nuclear alteration) in all studied fish traducing an important level of stress consistently with the high concentration of toxicant in this organ. On the other hand, antioxidant defenses biomarkers revealed differences between the studied morphotypes. Moreover, analysis of serum lysozyme activity showed that these salmonids were characterized by reduced immune competences. Kerguelen Islands constitute a workshop site for ecotoxicological studies. The long-term monitoring should improve the knowledge of changes in eco-physiological responses of freshwater fish populations dealing with the global chemical pressure
De, Oliveira Eric. « Analyse de l'activité d' une pêcherie à échelle spatio-temporelle fine : des captures répétitives aux puissances de pêche locales ». Paris, ENMP, 2003. http://www.theses.fr/2003ENMP1155.
Based on data issued from fishing observers on board, a local analysis of spatiotemporal distribution of fishing activity targeting Patagonian tooth fish in Kerguelen Island is performed. The main problem of this study is the important number of co-located catches and their high variability. The variogram decreases and isn't directly available. A geographical position can be exploited by a vessel several times or by different vessels, so local variability of catches has been decomposed in two composants, intra and inter vessels. Three causes of high variability are analyzed. First, series of collocated catches composed at least of three replications, have been used to establish and modelyse a local depletion effect (around 6%) of resource along the repetition and implies that of ensemble of catches is not representative of the same local abundance and increase local variability. Secondly, the change of fishery regulation implies an average decrease of fishing efficiency. Thirdly, estimation of local fishing power is based on comparisons between catches realized the same day by different vessels and by taking account the distance between catches. Results of this method are compared to results issued from a general linear model (variance analysis). Taking account of this three effects, cartography by kriging is performed. Local analysis of spatial distribution of fishing activity shows the importance of parameters which define fishing behavior and fishing tactics on their consequences on the level of catches. Usual geostatistical tools are malajusted to analyze commercial fishing data, and adapted methods have been developed
Laparie, Mathieu. « Succès invasif de deux insectes introduits aux îles Kerguelen : le rôle des ajustements morphologiques et écophysiologiques aux nouvelles conditions environnementales ». Phd thesis, Rennes 1, 2011. http://www.theses.fr/2011REN1S125.
The success of invasive species depends on the adequacy between their life history traits and the environmental characteristics (biotic and abiotic) of their new habitats. The invasive success may then rely on pre-adaptation, be triggered by the release of some selection pressures, perturbations, or quick responses of the organism to the new selection pressures. Phenotypic plasticity and evolutionary processes are then prime components in biological invasions, so that invasive species can be considered as key models for monitoring ecological and evolutionary processes in real time. We thus investigated morphological and ecophysiological responses produced in time and space during the invasion of the sub-Antarctic Kerguelen Islands by the predatory ground beetle Merizodus soledadinus and the saprophagous blowfly Calliphora vicina, which possess contrasted life strategies. We show morphological differentiation among populations of M. soledadinus depending on their residence time, as well as rapid changes of the C. Vicina's wing morphology in these islands where flightlessness is the rule. The invasion of M. soledadinus was studied with special emphasis on the role played by phenotypic plasticity in colonizing habitats that differ from native ones (physiological plasticity to salinity) and maintaining durable populations despite the negative feedback of this predator on the availability of its own prey (trophic plasticity). As they spread and encounter novel selection regimes, these adjustments at different timescales are of paramount importance in the invasive success of both these insect species
Bailleul, Frédéric. « Deux mille mètres sous les mers : stratégies d'acquisition des ressources et réponses comportementales des éléphants de mer de Kerguelen aux structures physiques de l'Océan Austral ». La Rochelle, 2006. http://www.theses.fr/2006LAROS176.
Understanding how organisms exploit the resources of their environment is a central topic in ecology. At first, this work describes the foraging strategies of the Southern elephant seals (Mirounga leonina) from Kerguelen Islands. Then, it investigates the relationships between foraging behaviour of this species and the environmental parameters and the physical structures of the Southern Ocean. The elephant seals from Kerguelen have exhibited a large distribution in the Southern Ocean but they have concentred their foraging activity within specific areas. Close to the Antarctic continent or within the polar frontal zone, their behaviour was influenced by sea ice. And eddies, respectively. Resources distribution and predictability were not necessary the unique parameter to explain behavioural adjustments of seals. This study takes place in a global project, which compare, on the one hand, the foraging behaviour of the three principal populations of elephant seals of the Southern Ocean, to contribute for understanding their demography and, on the other hand, to acquire oceanographic data in this part of the world
Ahadi, Floriane. « Taux et moteurs d’exhumation de complexes plutoniques en contexte intraplaque océanique (archipel de Kerguelen) : apports de la thermochronologie basse et moyenne température ». Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS425.
The main scientific aim of this work is the understanding of driving forces and erosion rates, at the scale of several dozens of millions of years, of an oceanic volcanic island. A low and mid temperature thermochronological approach on intrusive rocks is used, in order to reconstruct exhumation paths in the oceanic crust of the Kerguelen archipelago (southern Indian Ocean). This archipelago was created 30 Ma years ago and is the emerged part of the eponymous oceanic plateau, formed following the activity of the Kerguelen hot spot, which began 120 Ma ago. The singularity of the Kerguelen archipelago, compared to other oceanic islands, is the occurrence of acid plutonic rocks, on which we can perform thermochronology on. Such methods allow reconstructing the thermal cooling paths, and thus, exhumation paths of the plutons since their deep formation to their surface exhumation. In this work, three thermochronometers were used: the ⁴⁰Ar/³⁹Ar on biotite method, and the (U-Th)/He on apatite and zircon methods. The data obtained on Kerguelen Islands indicate a differential erosion over the archipelago, with local erosion pulses within a plutonic complex, contrasting with regional low erosion rates since 25 Ma. This observation points to the predominant role of magmatic activity, and the associated local tectonic activity, on the exhumation of plutonic bodies and surface denudation
Blot, Michel. « Les populations de Mytilidae de Kerguelen (océan Austral) : génétique et adaptation à l'environnement de Mytilus desolationis ». Paris 7, 1989. http://www.theses.fr/1989PA077018.
Bon, Cécile. « Stratégies de recherche alimentaire d'un prédateur plongeur en période de reproduction : le Gorfou Macaroni des îles Crozet et Kerguelen ». Thesis, La Rochelle, 2016. http://www.theses.fr/2016LAROS004/document.
The Austral Ocean still hosts a great population of marine predators (i.e. penguins, albatross, and seals). Despite well studied, the functional approach investigating the relationship between prey and predators in the marine ecosystem is still poorly known. Knowledge on habitat selection and use of marine species is essential to better understand their ecology and behaviour. The knowledge about the ecology of key species is essential to characterise and identify the areas to protect and to predict the future of populations that may be affected by global changes. This is particularly true in an area where the natural ecosystems are more and more perturbed by anthropogenic activities (i.e. over-fishing, pollution, and climate change). The Macaroni penguin is the most abundant penguin species in the Austral Ocean (> 6 millions pairs). It is also the biggest consumer of secondary resources, in terms of biomass, in the world. Over the past 30 years the Macaroni penguin populations situated in South Georgia and Marion Island suffered of 30% population decline. At the moment, Kerguelen and Crozet Islands (French Southern Territories) still host more than 50% of their global population, however the foraging behaviour of this species is still poorly known. The objective of this research is to study the different foraging behaviour strategies of a pelagic seabird : the Macaroni penguin Eudyptes chrysoplophus during its whole breeding cycle (incubation, brood, crèche). The populations’object of study breed in different oceanographic conditions : the Kerguelen and Crozet archipelagos. The variation in foraging behaviour driven by energetic constraints, which is associated to the reproduction and to the biological production, has been studied in details. Telemetry data (i e. trajectories and diving behaviour) combined with environmental data obtained by remote sensing allowed determining that : 1) Foraging strategies of Macaroni penguin breeding in two different locations differ in terms of movement, foraging effort and foraging niche during their breeding cycle in response to reproduction constraints. In incubation, both sexes carried out long journeys and targeted large oceanographic structures such as fronts, eddy and transport fronts. During the brooding phase, the females foraged closer to the colony adjusting their foraging behaviour based on their offspring needs, targeting the shelf and the slope. When crèche started, males targeted large scale structures whereas females still foraged on the slope. At this time, a shift in the diet composition was observed. 2) The comparative approach between Kerguelen and Crozet allowed to highlighting differences in foraging strategies, in response to local environmental conditions. However, greater than expected variations in foraging areas were observed inter-site and inter-sex. These results have pointed out an unexpected phenotypic flexibility for a pelagic marine predator. This research investigated the entire breeding cycle of a penguin, a fact still rare in ecology. The observed degree of behavioural variability reiterates the imperative to take into account an entire cycle to better understand and define the foraging strategies of a species
Grégoire, Michel. « Pétrologie des enclaves ultrabasiques et basiques des îles Kerguelen (TAAF) : les contraintes minéralogiques et thermobarométriques et leurs implications géodynamiques ». Saint-Etienne, 1994. http://www.theses.fr/1994STET4001.
Several occurences of ultrabasic and basic xenoliths, uplifted by peralkaline lavas, lay in the South-East province of the Kerguelen Islands. They display all types of both continental and oceanic UB-B inclusions, except eclogites. Such a wide diversity leads to a typology which is hierarchically classified by textural criteria (1st class) and by mineralogical ones (2nd class). Three main types and seven subtypes are proposed. The type I has mantle tectonite textures and it is divided in a subtype Iα (harzburgites) and in a subtype Iβ (dunites). The type II presents metamorphic textures with relicts of magmatic ones. It presents three subtypes : IIa (cpx + opx + sp), IIb (cpx + ilm + sp) et IIc (ilmenite bearing metagabbros). The type III has purely magmatic textures and it is represented by hornblenditic and biotitic inclusions. The present study focuses mainly on types I and II which are related to the lower crust and to the upper mantle. Inclusions of type I belong to the upper mantle and have been reequilibrated in the "spinel perioditic" stability field. They indicate the role of several mantle processes : partial melting, metasomatism, and magma-mantle interactions. The presence of a clinopyroxene in one of the two harzburgite types clearly expresses the interactions between mantle and magmas. A similar process plays a major role int he origin of the dunites and of the dunite-bearing composite xenoliths. The inclusions of type II were initially magmatic cumulates and segregates. The type IIa consists of a complete series of rocks, from ultrabasic peridotites to basic metagabbros, and may be related to the tholeiitic-transtional magmatism of the archipelago. Some of the sympletitic and coronitic reactions lead to mineral associations with sapphirine ± garnet which expresses reequilibrations in the granulite facies conditions, from 0. 5 to 1. 6 GPa and from 900 to 1000°C. The type IIb differs in that it corrsponds to mineral segregates, occuring fromalkaline magmas in the upper mantle layers (0. 7 to 1. 35 GPa, 850 to 1000°C). The type IIc is an homogeneous group of rocks, of which the composition is close to the tholeiitic-transitional volcanic liquids and have been reequilibrated in the granulite facies conditions. Discussion supporetd by geochronological and geophysical data argues and explains the crustal thickeneing which was previously deduced from the deep seismic velocity variations. The Northern end of the Kerguelen plateau was formed when the junction occured between the India/Antarctic ridge and of the Australia/Antarctic one, at 56 to 43 Ma. The synergy of the young East-Indian Ridge and of the Kerguelen hot spot was at the origin of a very voluminous production of tholeiitic-transtional magmas of which many cumulates and segregates were underplated in the viscinity of the Moho. This process of crustal thickening by underplating was later amplified by the volcanic overload related to the logevity of the hot spot. Then, while their temperature slowly decreased, the UB-B cumulates were sunk to depths at which they were reequilibrated into granulite facies conditions. The younger alkaline magmas then uplifted pieces of these deep rocks. Such a crustal thickening, as well as some specific features of the magmatic complexes of the archipelago, allow the assumption of an anomalous weak density of the lithosphere, and consequently leads one to propose the unsubductability of Kerguelen islands which may be considered then as a continental protolith
Labarrere, Bastien. « Comment les plantes répondent et s'adaptent aux changements climatiques : étude aux marges froides (subantarctique) ». Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1B002/document.
The adaptive potential of a species can be defined as its capacity to cope with environmental change. Adaptive potential increases with phenotypic variation, from the intra-individual to the inter-population level, but factors controlling and explaining this variation still remain poorly understood.We studied four plant species from Iles Kerguelen in the sub-Antarctic region which is currently facing one of the strongest climate changes worldwide. Plant species from Iles Kerguelen are known to show high phenotypic integration (i.e. strong correlation among traits), a phenomenon that has been suggested to constrain trait variation. For these species we studied what constrains phenotypic variation, considering the external environment, the internal phenotypic integration and the associated performance costs. We found that intra-individual variation, i.e. plasticity, may be constrained by complex environmental change and the performance costs it triggers. In contrast, plasticity may be favored by high degree of phenotypic integration (Chapter 3). We found that inter-individual variation within populations may not be constrained by environmental factors, but may be favored by high phenotypic integration (Chapter 1). We found inter-population variation within regions may be constrained by restricted environmental variation (Chapter 1). Finally, we studied secondary metabolites (amines and flavonols) that connect environmental variation to phenotypic variation. We found that compositions and functions of these metabolites vary among regions, probably reflecting evolutionary differentiation among regions (Chapter 2). Patterns of variation betweenregions suggest that within species metabolites may be functionally redundant or versatile, for which to our knowledge our results are the first hint. Overall, we suggest that climate change in Kerguelen will impact plant species performance, and that the persistence of suitable wet habitats will be determinant in species capacities to cope with such changes. Furthermore, this project identified so far underestimated factors which may favor the adaptive potential of species. Particularly, we emphasize that the adaptive potential of species may increase due to (i) phenotypic integration, (contrary to common suggestion) and (ii) metabolite redundancy or versatility (only poorly studied so far). Moreover, we evidenced, partly for the first time, multiple costs and limits of plasticity and suggest that plasticity does not guarantee plant success in the new environment
Della, Penna Alice. « Living in a fluid-dynamical landscape : how do marine predators respond to turbulence ? » Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC066.
Marine top predators play a fundamental role in maintaining the structure and functioning of healthy marine ecosystems. In the last decades the development of bio-Iogging (i. E. Deployment of autonomous recording tags on free-living animals) has radically changed the study of top predators and their interactions with their environment. Combinations of sensors measuring position (Argos and GPS), environmental properties (water temperature, light) and proxies for foraging behavior (accelerometers) have enabled relating migrations of large fish, marine mammals, sea turtles and seabirds to basin scale patterns of ocean currents, temperature, and productivity. However, what influences marine predators' movement at smaller spatial and temporal scales, such as the ones they experience during their foraging trips, is still largely unknown. This project analyses the interaction between marine top predators (elephant seals and macaroni penguins) and sub-mesoscale (few days-months, 10-100 km) ocean dynamics. This is achieved by combining in-situ observations, bio-logging data, remote-sensing, ecological modelling and a Lagrangian approach (i. E. Based on the tracking of water parcels). The study is conducted in the sub-Antarctic region around the Kerguelen Plateau (Indian Sector of the Southern Ocean)
Aulus-Giacosa, Lucie. « Spatio-temporal evolution of life history traits related to dispersal. Brown trout (Salmo trutta L.) colonization of the sub-Antarctic Kerguelen Islands ». Thesis, Pau, 2021. http://www.theses.fr/2021PAUU3003.
It is an ongoing issue to better understand colonization process, adaptation potential to new environments, and invasiveness of a species. The sub Antarctic Kerguelen Islands are a perfect model to model population dynamics in an invasion context, because it represents a simplified case of invasion by brown trout (Salmo trutta L.), a facultative anadromous fish. Introduced in the 1950s, and thanks to its dispersive and adaptive capacities, the brown trout provides a unique study model for understanding the causes and mechanisms underlying biological invasions. Understanding dispersal mechanisms, through the study of life history traits related to migration (e.g. growth, age at migration) and their temporal evolution in shifting expansion range population, is the core of this thesis work. Through the study of scales collected in this unique framework, the life histories of nearly 5000 fish have been rebuilt. This work demonstrates the importance of the methodology to determine accurate estimates of individual life history traits. Modelling the evolution of freshwater growth, body size at age and age at first migration demonstrates that evolutionary processes are at work according to the time since colonization. In particular, the decrease in growth rate over time and the decrease in body size at age over time and space suggest that the dispersal capacity is decreasing in populations located at the margins. The evolution of the threshold size at first migration confirms this results, and illustrates the importance of phenotypic plasticity and local adaptation in the choice of migratory tactics. However, the approach taken in this manuscript focuses on the evolution of migration, and would benefit from the study of the joint evolution of traits involved in fitness (costs-benefits balance), such as reproduction, or growth at sea
Verfaillie, Deborah. « Suivi et modélisation du bilan de masse de la calotte Cook aux iles Kerguelen. Lien avec le changement climatique ». Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU035/document.
Glaciers of the southern hemisphere sub-polar regions between 45 and 60°S have declined dramatically over the last century. The islands of Kerguelen archipelago (49°S, 69°E) represent a unique location in regions where few data are available to understand glacier retreat. Situated at low altitudes and close to the ocean, their glaciers have shown particular sensitivity to atmospheric and oceanic variations. Thus, since the 1960s, the Cook Ice Cap (~400km2) has retreated spectacularly, losing 20% of its area in 40 years. The aim of my thesis was to assess the present and future state of the ice cap, and to understand the causes of this decline while putting them in a global context. To do so, a meteorological and glaciological network was set up in 2010 on Kerguelen archipelago and field campaigns have been carried out annually since then. Analysis of these measurements confirms the negative mass balance of Cook Ice Cap. In parallel, the study of the albedo over the whole ice cap from MODIS satellite images (MODerate resolution Imaging Spectroradiometer) gives us access to the evolution of the snow line since 2000, highlighting an important reduction of Cook Ice Cap accumulation area over the last decade. Mass balance modelling of the Cook Ice Cap using a degree-day model coupled to a simple ice motion routine further reveals that its retreat is mainly due to a strong decrease in precipitation over the Kerguelen Islands since the 1960s. In order to put the decline of the cryosphere on Kerguelen in a global context, climatic trends over the whole sub-polar regions are studied, revealing that the sub-Antarctic area is currently the one where glacier retreat is the strongest. To understand these variations, we analyse a complete set of field and satellite observations and modelling results : reanalyses, models from the CMIP5 (Coupled Model Intercomparison Project phase 5) experiment, atmospheric and oceanic temperature and precipitation observations, etc. The latter show warming and quasigeneralised drying of the whole 40-60°S area, linked to the southward shift of storm tracks in response to the more frequent positive phases of the Southern Annual Mode (SAM). Recent glacier retreat on Kerguelen archipelago, and for other glaciers and ice caps located at similar latitudes, is thus mainly due to a deficit of accumulation caused by the SAM, and amplified by atmospheric warming. The future evolution of Cook Ice Cap mass balance is evaluated using the MAR (Modèle Atmosphérique Régional) model, forced at its boundaries by CMIP5 models. Recent mass balance simulations are first carried out using ERA-Interim and NCEP1 reanalyses, and compared to in situ observations. In parallel, one-year simulations are produced with the precipitation desagregation scheme SMHiL (Surface Mass balance High resolution downscaLing) on MAR outputs, at various scales, in order to evaluate the impact of downscaling on precipitation. An evaluation of CMIP5 models over the recent period against ERA-Interim is then carried out, considering certain key climatic variables. The model closest to ERA-Interim as well as the two most extreme models are then used to force the MAR model over the next century, and surface mass balance outputs are critically analysed. The analysis of the decline of the Kerguelen ice cap using different tools and techniques brought new insights on the link between glaciers and climate, highlighting the major role of the SAM, but also raised new questions
Mestre, Julie. « Entre variabilité interannuelle et stratégies individuelles : effets des paramètres environnementaux sur l’écologie alimentaire et le succès reproducteur des éléphants de mer de l’archipel de Kerguelen ». Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS228.
Because time-series relative to foraging ecology, environmental parameters and population trends are scarce, few studies focused on the mechanisms linking oceanographic variables with the foraging behaviour and breeding success in marine top predators. This PhD thesis aims to assess the effects of inter-annual environmental conditions and individual strategies on the foraging ecology and breeding success of the southern elephant seal (Mirounga leonina), a key species of the Southern Ocean. The simultaneous analysis of stable isotopes and tracking-diving time-series highlighted that the foraging habitats, as well as the diving- and foraging behaviour of female seals, remained stable over the last fourteen years. This thesis also revealed a consistency in the Antarctic and sub-Antarctic foraging strategies, and a decrease in the body condition of females exploiting the latter habitat. The weaning mass of their pups, considered as a proxy of the breeding success, decreased too. A difference in habitat quality was detected between the area located east and west of the Kerguelen archipelago, with the area located west providing a higher foraging success. Moreover, a spatial structuration of foraging strategies was highlighted between two breeding sites located at Kerguelen Island. Despite consistency in the behaviour of seals, an overall increase in body condition was assessed over the study period. Combined with a global decrease in δ13C values, this result suggests that some modifications are occurring in the food web of the Southern Ocean
Labrousse, Sara. « Beneath the sea ice : exploring elephant seal foraging strategy in Earth's extreme Antarctic polar environment ». Electronic Thesis or Diss., Paris 6, 2016. http://www.theses.fr/2016PA066542.
Understanding how physical properties of the environment underpin habitat selection of large marine vertebrates is crucial in identifying how and where animals acquire resources necessary for locomotion, growth and reproduction and ultimately their fitness. The Southern Ocean harbors one of the largest and most dynamic marine ecosystems on our planet which arises from the presence of two majors physical features, (i) the Antarctic Circumpolar Current and (ii) the seasonal sea ice cover region. In the Antarctic, marine predators are exposed to climate-induced shifts in atmospheric circulation and sea ice. However, because these shifts vary regionally, and because much remains to be understood about how individual animals use their environment, it has been difficult to make predictions on how animals may respond to climate variability. Southern elephant seals (Mirounga leonina) are a major consumer of Southern Ocean resources and use two main large scale foraging strategies, (i) feeding in the frontal zone of the Southern Ocean, or (ii) feeding in the seasonal sea ice region. In the present thesis I examined the winter post-moulting foraging strategies of 46 male and female Kerguelen southern elephant seals which utilized the second strategy. Using an eleven year time-series of tracking, diving, and seal-collected hydrographic data (from 2004-2014) I assessed their movements and foraging performance in relation to in situ hydrographic and sea ice conditions. The influence of both the spatio-temporal and inter-annual variability of sea ice around seal locations was investigated, and an investigation on the role of polynya for male elephant seal during winter conducted
Beaux, Jean-François. « Le complexe volcano-plutonique de la presqu'île de la société de géographie (Iles Kerguelen) : structure et pétrologie ». Paris 6, 1986. http://www.theses.fr/1986PA066198.
Baudena, Alberto. « How do marine mid trophic levels respond to fine scale processes ? » Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS136.
The comprehension of the coupling between physical and biological dynamics is a pivotal step to assess the health of the oceans, in order to protect the ecosystems therein from the effects of global change, human exploitation and pollution as well as for understanding the role of the ocean in the climate system. Indeed, in the oceans, physical phenomena and biological processes are intimately linked, since marine organisms live in a fluid environment, continuously under the effect of the currents. Thus, contrary to what happens on land, where the landscape topography changes over evolutionary timescales (periods in the order of hundreds to millions of year) in the ocean the landscape ("seascape") evolves on the same timescales of ecological processes. In the present thesis I analyse in particular the role of the fine scales, which present a peak in the ocean energy spectrum, and whose time scales (of days to weeks) overlap important marine ecological processes like the development of planktonic blooms and the duration of foraging trips for top predators. The fine scale features have been already shown to play a central role into conditioning primary production, lower trophic levels abundance and composition, and apex predators behaviors. However, less is known on their influence on intermediate trophic levels, i.e. swimming organisms (such as fish), which however constitute an essential part of the trophic chain, and which are under unprecedented pressure by human activities. This is mainly due to the scarce availability of data on them at large scales, and to problems of ship-based measurements. Two knowledge gaps are addressed in this thesis. The first is the fact that intermediate trophic levels distributions cannot be detected by remote sensing, and thus require the development of novel, ad hoc sampling strategies. The second open challenge addressed by this thesis is how the swimming ability of the nekton can interact with the fine scale physical dynamics. In order to address the aforementioned questions, in this work I adopt a Lagrangian approach, therefore focusing on water parcel trajectories, and I integrate it with novel methodologies applied to acoustic data, complex system analysis and network theory. I focus on the Kerguelen region, because of its ecological importance and the large availability of informations, which permitted to characterize its relatively simple ecological dynamics, mainly based on iron limitation which is furnished by the plateau. I consider the myctophids as reference fish of the present study, for their worldwide abundance and for their importance for the ecology of the area, and because they may constitute a future target by commercial fishing. (...)
Labrousse, Sara. « Beneath the sea ice : exploring elephant seal foraging strategy in Earth's extreme Antarctic polar environment ». Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066542/document.
Understanding how physical properties of the environment underpin habitat selection of large marine vertebrates is crucial in identifying how and where animals acquire resources necessary for locomotion, growth and reproduction and ultimately their fitness. The Southern Ocean harbors one of the largest and most dynamic marine ecosystems on our planet which arises from the presence of two majors physical features, (i) the Antarctic Circumpolar Current and (ii) the seasonal sea ice cover region. In the Antarctic, marine predators are exposed to climate-induced shifts in atmospheric circulation and sea ice. However, because these shifts vary regionally, and because much remains to be understood about how individual animals use their environment, it has been difficult to make predictions on how animals may respond to climate variability. Southern elephant seals (Mirounga leonina) are a major consumer of Southern Ocean resources and use two main large scale foraging strategies, (i) feeding in the frontal zone of the Southern Ocean, or (ii) feeding in the seasonal sea ice region. In the present thesis I examined the winter post-moulting foraging strategies of 46 male and female Kerguelen southern elephant seals which utilized the second strategy. Using an eleven year time-series of tracking, diving, and seal-collected hydrographic data (from 2004-2014) I assessed their movements and foraging performance in relation to in situ hydrographic and sea ice conditions. The influence of both the spatio-temporal and inter-annual variability of sea ice around seal locations was investigated, and an investigation on the role of polynya for male elephant seal during winter conducted
Massardier-Galatà, Lauriane. « Succès de la reproduction de prédateurs en contexte de changements climatiques et de la dynamique océanique – Application aux « central place foragers » des zones australes, approche par la modélisation individu centrée ». Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4050/document.
Climate change has certain impact on the marine ecosystems. A southward shift in productive frontal systems serving as the main foraging sites for many top predator species is likely to occur in the Subantarctic areas. Central place foragers, as seabirds and pinnipeds, are thus likely to cope with an increase in the distance between foraging locations and their land-based breeding colonies. We studied the impact of climate change on the breeding success and population dynamics of Antarctic fur seals (Arctocephalus gazella) at Kerguelen Islands by means of an individual based model we developped, MarCPFS (Marine Central Place Foragers Simulator) which showed that the survival of the female-pup pair is particularly sensitive to the distribution of preys (abundance and structure), to the memorization abilities of the best resource sites found by the female during the rearing period, to the female size and to the foraging distance which it is necessary to cover at each trip. The results suggest that during the next three decades a southward shift greater than 2 km year-1 could compromise the survival and the sustainability of the populations. A coupling with a model of simulation of the oceanic dynamics and the resource (SEAPODYM) allowed projections till the end of this century based on scenarios RCP8.5 of the IPCC (2014), confirming the trends previously obtained. Globally, these works lead us to conclude with pessimistic perspectives about the sustainability of populations even when considering an evolution through time towards individuals of greater sizes