Academic literature on the topic 'Baleines à bec – Observations'

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Journal articles on the topic "Baleines à bec – Observations"

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Gérard, Odile, Craig Carthel, and Stefano Coraluppi. "Détection et classification automatique de signaux acoustiques de baleines à bec." Traitement du signal 33, no. 1 (October 28, 2016): 73–94. http://dx.doi.org/10.3166/ts.33.73-94.

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Kun, E., Z. Keresztes, and L. Á. Gergely. "Slowly rotating Bose–Einstein condensate compared with the rotation curves of 12 dwarf galaxies." Astronomy & Astrophysics 633 (January 2020): A75. http://dx.doi.org/10.1051/0004-6361/201936504.

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Context. The high plateaus of the rotation curves of spiral galaxies suggest either that there is a dark component or that the Newtonian gravity requires modifications on galactic scales to explain the observations. We assemble a database of 12 dwarf galaxies, for which optical (R-band) and near-infrared (3.6 μm) surface brightness density together with spectroscopic rotation curve data are available, in order to test the slowly rotating Bose–Einstein condensate (BEC) dark matter model. Aims. We aim to establish the angular velocity range compatible with observations, bounded from above by the requirement of finite-size halos, to check the model fits with the dataset, and the universality of the BEC halo parameter ℛ. Methods. We constructed the spatial luminosity density of the stellar component of the dwarf galaxies based on their 3.6 μm and R-band surface brightness profiles, assuming an axisymmetric baryonic mass distribution with arbitrary axis ratio. We built up the gaseous component of the mass by employing an inside-truncated disk model. We fitted a baryonic plus dark matter combined model, parametrized by the M/L ratios of the baryonic components and parameters of the slowly rotating BEC (the central density ρc, size of the BEC halo ℛ in the static limit, angular velocity ω) to the rotation curve data. Results. The 3.6 μm surface brightness of six galaxies indicates the presence of a bulge and a disk component. The shape of the 3.6 μm and R-band spatial mass density profiles being similar is consistent with the stellar mass of the galaxies emerging wavelength-independent. The slowly rotating BEC model fits the rotation curve of 11 galaxies out of 12 within the 1σ significance level, with the average of ℛ as 7.51 kpc and standard deviation of 2.96 kpc. This represents an improvement over the static BEC model fits, also discussed. For the 11 best-fitting galaxies the angular velocities allowing for a finite-size slowly rotating BEC halo are less then 2.2 × 10−16 s−1.For a scattering length of the BEC particle of a ≈ 106 fm, as allowed by terrestrial laboratory experiments, the mass of the BEC particle is slightly better constrained than in the static case as m ∈ [1.26 × 10−17 ÷ 3.08 × 10−17] (eV c−2).
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Morawska, Alina, Michelle Adamson, and Joanne Ferriol Especkerman. "Mealtime Observations and Parent-Report: Correspondence Across Measurement and Implications for Intervention." Behaviour Change 32, no. 3 (July 27, 2015): 175–89. http://dx.doi.org/10.1017/bec.2015.9.

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This study explored the relationship between self-reported and observed mealtime behaviour and examined concurrent predictors of observed child and parent mealtime behaviour. The sample consisted of 67 parents of 1.5- to 6-year-old children experiencing difficulties with their child's mealtime, and 33 parents who were not concerned with their child's mealtime behaviour. Parent-reported and observed mealtime data, and parent-reported mealtime cognitions were collected. Regression analyses indicated that consistent with hypotheses, observed and parent-reported mealtime behaviour were related. Observed child behaviour was predicted by self-reported parenting behaviour and observed positive parent behaviour, as well as parental cognitions. Observed parent behaviour was predicted only by self-reported parenting mealtime behaviour.
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Davis, Benjamin, Xuguang Wang, and Xu Lu. "A Comparison of HWRF Six-Hourly 4DEnVar and Hourly 3DEnVar Assimilation of Inner Core Tail Dopper Radar Observations for the Prediction of Hurricane Edouard (2014)." Atmosphere 12, no. 8 (July 22, 2021): 942. http://dx.doi.org/10.3390/atmos12080942.

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Six-hourly three-dimensional ensemble variational (3DEnVar) (6H-3DEnVar) data assimilation (DA) assumes constant background error covariance (BEC) during a six-hour DA window and is, therefore, unable to account for temporal evolution of the BEC. This study evaluates the one-hourly 3DEnVar (1H-3DEnVar) and six-hourly 4DEnVar (6H-4DEnVar) DA methods for the analyses and forecasts of hurricanes with rapidly evolving BEC. Both methods account for evolving BEC in a hybrid EnVar DA system. In order to compare these methods, experiments are conducted by assimilating inner core Tail Doppler Radar (TDR) wind for Hurricane Edouard (2014) and by running the Hurricane Weather Research and Forecasting (HWRF) model. In most metrics, 1H-3DEnVar and 6H-4DEnVar analyses and forecasts verify better than 6H-3DEnVar. 6H-4DEnVar produces better thermodynamic analyses than 1H-3DEnVar. Radar reflectivity shows that 1H-3DEnVar produces better structure forecasts. For the first 24–48 h of the intensity forecast, 6H-4DEnVar forecast performs better than 1H-3DEnVar verified against the best track. Degraded 1H-3DEnVar forecasts are found to be associated with background storm center location error as a result of underdispersive ensemble storm center spread. Removing location error in the background improves intensity forecasts of 1H-3DEnVar.
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Kim, Sung-Min, and Hyun Mee Kim. "Forecast Sensitivity Observation Impact in the 4DVAR and Hybrid-4DVAR Data Assimilation Systems." Journal of Atmospheric and Oceanic Technology 36, no. 8 (August 2019): 1563–75. http://dx.doi.org/10.1175/jtech-d-18-0240.1.

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AbstractIn this study, the observation impacts on 24-h forecast error reduction (FER), based on the adjoint method in the four-dimensional variational (4DVAR) data assimilation (DA) and hybrid-4DVAR DA systems coupled with the Unified Model, were evaluated from 0000 UTC 5 August to 1800 UTC 26 August 2014. The nonlinear FER in hybrid-4DVAR was 12.2% greater than that in 4DVAR due to the use of flow-dependent background error covariance (BEC), which was a weighted combination of the static BEC and the ensemble BEC based on ensemble forecasts. In hybrid-4DVAR, the observation impacts (i.e., the approximated nonlinear FER) for most observation types increase compared to those in 4DVAR. The increased observation impact from using hybrid-4DVAR instead of 4DVAR changes depending on the analysis time and regions. To calculate the ensemble BEC in hybrid-4DVAR, analyses at 0600 and 1800 UTC (0000 and 1200 UTC) used 3-h (9-h) ensemble forecasts. Greater observation impact was obtained when 3-h ensemble forecasts were used for the ensemble BEC at 0600 and 1800 UTC, than with 9-h ensemble forecasts at 0000 and 1200 UTC. Different from other observations, the atmospheric motion vectors (AMVs) deduced from geostationary satellite are more frequently observed in the same area. When the ensemble forecasts with longer integration times were used for the ensemble BEC in hybrid-4DVAR, the observation impact of the AMVs decreased the most in East Asia. This implies that the observation impact of AMVs in East Asia shows the highest sensitivity to the integration time of the ensemble members used for deducing the flow-dependent BEC in hybrid-4DVAR.
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Barthelemy, Dominique. "Une crise de l’écrit ? Observations sur des actes de Saint-Aubin d’Angers (XIe siècle)." Bibliothèque de l'école des chartes 155, no. 1 (1997): 95–117. http://dx.doi.org/10.3406/bec.1997.450860.

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Castellanos, Elías, Celia Escamilla-Rivera, and Jorge Mastache. "Is a Bose–Einstein condensate a good candidate for dark matter? A test with galaxy rotation curves." International Journal of Modern Physics D 29, no. 09 (July 2020): 2050063. http://dx.doi.org/10.1142/s0218271820500637.

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We analyze the rotation curves that correspond to a Bose–Einstein Condensate (BEC)-type halo surrounding a Schwarzschild-type black hole to confront predictions of the model upon observations of galaxy rotation curves. We model the halo as a BEC in terms of a massive scalar field that satisfies a Klein–Gordon equation with a self-interaction term. We also assume that the bosonic cloud is not self-gravitating. To model the halo, we apply a simple form of the Thomas–Fermi approximation that allows us to extract relevant results with a simple and concise procedure. Using galaxy data from a subsample of SPARC data base, we find the best fits of the BEC model by using the Thomas–Fermi approximation and perform a Bayesian statistics analysis to compare the obtained BEC’s scenarios with the Navarro–Frenk–White (NFW) model as pivot model. We find that in the centre of galaxies, we must have a supermassive compact central object, i.e. supermassive black hole, in the range of [Formula: see text] which condensate a boson cloud with average particle mass [Formula: see text] eV and a self-interaction coupling constant [Formula: see text], i.e. the system behaves as a weakly interacting BEC. We compare the BEC model with NFW concluding that in general the BEC model using the Thomas–Fermi approximation is strong enough compared with the NFW fittings. Moreover, we show that BECs still well-fit the galaxy rotation curves and, more importantly, could lead to an understanding of the dark matter nature from first principles.
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Kay, Junkyung, and Xuguang Wang. "A Multiresolution Ensemble Hybrid 4DEnVar for Global Numerical Prediction." Monthly Weather Review 148, no. 2 (February 1, 2020): 825–47. http://dx.doi.org/10.1175/mwr-d-19-0002.1.

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Abstract A multiresolution ensemble (MR-ENS) method is developed to resolve a wider range of scales of the background error covariance (BEC) in the hybrid four-dimensional ensemble–variational (4DEnVar) while saving computational costs. MR-ENS is implemented in the NCEP Global Forecast System (GFS) gridpoint statistical interpolation (GSI) hybrid 4DEnVar. MR-ENS generates analysis increment by incorporating high-resolution static BEC and flow-dependent ensemble BECs from both high and low resolutions. MR-ENS is compared with three 4DEnVar update approaches: 1) the single-resolution (SR)-Low approach where the analysis increments are generated from the ensemble BEC and the static BEC at the same low resolution; 2) the dual-resolution (DR) approach where the analysis increment is generated using the high-resolution static BEC and low-resolution ensemble BEC; and 3) the SR-High approach, which is the same as 1) except that all covariances are at high-resolution. Experiments show that MR-ENS improves global and tropical cyclone track forecasts compared to SR-Low and DR. Inclusion of the high-resolution ensemble leads to increased background ensemble spread, better fitting of the background to observations, increased effective ranks, more accurate ensemble error correlation, and increased power of analysis increment at small scales. The majority of the improvement of MR-ENS relative to SR-Low is due to the partial use of high-resolution background ensemble. Compared to SR-High, MR-ENS decreases the overall cost by about 40% and shows comparable global and tropical cyclone track forecast performances. Diagnostics show that particularly in the tropics, MR-ENS improves the analysis increment over a wide range of scales and increases the effective rank of the ensemble BEC to the degree comparable to SR-High.
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Horne, David James de Lancy. "The Emergence and Development of Cognitive Behaviour Therapy in Australia: Observations from an Early Player." Behaviour Change 36, no. 4 (November 29, 2019): 192–99. http://dx.doi.org/10.1017/bec.2019.18.

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Xie, Jiping, Roshin P. Raj, Laurent Bertino, Annette Samuelsen, and Tsuyoshi Wakamatsu. "Evaluation of Arctic Ocean surface salinities from the Soil Moisture and Ocean Salinity (SMOS) mission against a regional reanalysis and in situ data." Ocean Science 15, no. 5 (September 6, 2019): 1191–206. http://dx.doi.org/10.5194/os-15-1191-2019.

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Abstract. Recently two gridded sea surface salinity (SSS) products that cover the Arctic Ocean have been derived from the European Space Agency (ESA)'s Soil Moisture and Ocean Salinity (SMOS) mission: one developed by the Barcelona Expert Centre (BEC) and the other developed by the Ocean Salinity Expertise Center of the Centre Aval de Traitement des Données SMOS at IFREMER (The French Research Institute for Exploitation of the Sea) (CEC). The uncertainties of these two SSS products are quantified during the period of 2011–2013 against other SSS products: one data assimilative regional reanalysis; one data-driven reprocessing in the framework of the Copernicus Marine Environment Monitoring Services (CMEMS); two climatologies – the 2013 World Ocean Atlas (WOA) and the Polar science center Hydrographic Climatology (PHC); and in situ datasets, both assimilated and independent. The CMEMS reanalysis comes from the TOPAZ4 system, which assimilates a large set of ocean and sea-ice observations using an ensemble Kalman filter (EnKF). Another CMEMS product is the Multi-OBservations reprocessing (MOB), a multivariate objective analysis combining in situ data with satellite SSS. The monthly root mean squared deviations (RMSD) of both SMOS products, compared to the TOPAZ4 reanalysis, reach 1.5 psu in the Arctic summer, while in the winter months the BEC SSS is closer to TOPAZ4 with a deviation of 0.5 psu. The comparison of CEC satellite SSS against in situ data shows Atlantic Water that is too fresh in the Barents Sea, the Nordic Seas, and in the northern North Atlantic Ocean, consistent with the abnormally fresh deviations from TOPAZ4. When compared to independent in situ data in the Beaufort Sea, the BEC product shows the smallest bias (< 0.1 psu) in summer and the smallest RMSD (1.8 psu). The results also show that all six SSS products share a common challenge: representing freshwater masses (< 24 psu) in the central Arctic. Along the Norwegian coast and at the southwestern coast of Greenland, the BEC SSS shows smaller errors than TOPAZ4 and indicates the potential value of assimilating the satellite-derived salinity in this system.
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Dissertations / Theses on the topic "Baleines à bec – Observations"

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Tournier, Martin. "Caractérisation et modélisation de l’habitat physique et biologique vertical des mammifères marins grands plongeurs." Thesis, La Rochelle, 2022. http://www.theses.fr/2022LAROS018.

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Les mammifères marins grands plongeurs évoluent dans un environnement tridimensionnel dans lequel les conditions physiques et biologiques varient. Les variations de ces conditions peuvent influencer leur utilisation de la dimension verticale. Les travaux de cette thèse s’appuient dans un premier temps sur le traitement du signal acoustique échantillonné par un échosondeur miniaturisé déployé sur des éléphants de mer austraux, pour apporter une caractérisation biologique inédite de la colonne d’eau. A travers ce signal acoustique ont pu être observés des organismes des niveaux trophiques intermédiaires, mais aussi des évènements d’export particulaire importants. Pour déterminer l’influence des variables environnementales dynamiques, telles que la température ou la salinité, sur la position verticale des éléphants de mer et des baleines à bec de Blainville, nous avons proposé une approche méthodologique adaptée à l’utilisation des profils environnementaux en tant que prédicteurs, et ce en utilisant des approches d’analyses fonctionnelles. En utilisant les variables collectées in situ par les éléphants de mer, il en ressort que leur profondeur de plongée est effectivement influencée par les profils environnementaux. En revanche, la prédiction de la position verticale à partir du modèle construit tend à sous-estimer la profondeur à laquelle se trouvent les animaux, notamment dans les zones marquées par une forte dynamique océanique. À l’inverse, la même approche appliquée au jeu de donnée restreint des baleines à bec et avec variables environnementales issues de modèles océanographiques, suggère l’absence d’effet des conditions environnementales sur leur utilisation de la colonne d’eau. Sous réserve de données de résolution spatio-temporelle suffisante, la méthodologie proposée pourrait permettre l’intégration de la dimension verticale dans la conception de modèles d’habitats tridimensionnels
Deep-diving mammals evolve within a tri-dimensional environment where the physical and biological conditions vary. These variations can influence their utilization of the vertical dimension. This Ph.D. thesis focuses, first, on acoustic signal analysis, the signal being sampled by a miniaturized echo-sounder deployed on southern elephant seals, and aims at biologically describing the water column. Through that acoustic signal, mid-trophic level organisms have been observed, as well as important particle export. Second, to determine the influence of dynamic environmental variables, such as temperature or salinity, on the vertical position of elephant seals and Blainville’s beaked whales, we proposed a new methodology suitable for using environmental predictors described in the form of profiles by using functional analysis approaches. When using the variables obtained in situ by elephant seals, we show that the environmental profiles influence the depth of the dives. However, the model tends to underestimate the predicted depth of animals, mainly in areas where high oceanic dynamics are observed. When using the same approach on the restricted beaked whales’ dataset, and by using environmental variables obtained from oceanographic models, we did not observe any impact of the environmental conditions on the whales’ water column use. This methodological approach could allow the integration of the vertical dimension toward the development of tri-dimensional habitat modelling under the conditions that the spatial and temporal resolutions of the dataset are adequate
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Virgili, Auriane. "Modelling distributions of rare marine species : the deep-diving cetaceans." Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS003/document.

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Les cétacés grands plongeurs, cachalots Physeteridae et Kogiidae, et baleines à bec Zipiidae, sont des espèces marines rares. Leur faible densité, aire de distribution étendue et faible disponibilité en surface génèrent de faibles taux d’observations. Cette particularité constitue un défi pour la modélisation d’habitat de ces espèces, préalable à leur conservation. Les modèles doivent gérer l’abondance de zéros qui limitent leur capacité à inférer des résultats écologiquement cohérents. Cette thèse vise donc à trouver une méthodologie adaptée aux jeux de données abondants en zéros, à déterminer comment les variables environnementales influencent la distribution des grands plongeurs et à prédire les zones potentielles qu’ils utilisent. Tester la capacité de prédiction de différents modèles d'habitat confrontés à un nombre décroissant d’observations a permis de souligner la pertinence d’un modèle, même si un minimum de 50 observations est nécessaire pour fournir des prédictions fiables. Des données issues de différentes campagnes visuelles ont été assemblées afin de produire les premières cartes de densités de grands plongeurs à l’échelle de l’océan Atlantique Nord et la mer Méditerranée. Les densités les plus élevées sont prédites dans les eaux entre 1500 et 4000 m de profondeur et près des fronts thermiques, particulièrement le long des pentes continentales et à l'ouest de l'océan Atlantique Nord. Par ailleurs, l’analyse de la transférabilité des modèles a montré une variation des habitats préférentiels en fonction des écosystèmes. Finalement, cette thèse permet de discuter les défis de la modélisation statistique appliquée aux espèces rares et les applications de gestion associées
Deep-diving cetaceans, sperm- and beaked whales Physeteridae, Kogiidae and Ziphiidae, are rare marine species. Due to their low densities, wide distribution ranges and limited presence at the water surface, visual surveys usually result in low sighting rates. This paucity of data challenges the modelling of their habitat, prerequisite for their conservation. Models have to cope with a great number of zeros that weakens the ability to make sound ecological inferences. Consequently, this thesis aimed at finding a methodology suitable for datasets with a large number of zeros, determining how environmental variables influence deep-diver distributions and predicting areas preferentially used by these species. By testing the predictive performance of various habitat models fitted to decreasing numbers of sightings, I selected the most suitable model and determined that at least 50 sightings were needed to provide reliable predictions. However, individual surveys can rarely provide sufficient deep-diver sightings thus I merged many visual survey datasets to produce the first basin-wide deep-diver density maps in the North Atlantic Ocean and the Mediterranean Sea. Highest densities were predicted in waters from 1500-4000 m deep and close to thermal fronts ; hotspots were predicted along the continental slopes, particularly in the western North Atlantic Ocean. In addition, a model transferability analysis highlighted that habitat drivers selected by the models varied between contrasted large ecosystems. Finally, I discussed challenges related to statistical modelling applied to rare species and the management applications of this thesis
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Patris, Julie. "Contributions en méthodes pour le suivi de mysticètes par acoustique passive." Electronic Thesis or Diss., Toulon, 2019. http://www.theses.fr/2019TOUL0016.

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La surveillance par acoustique passive est un outil d'importance croissante pour l'étude des mammifères marins. Cette thèse pose des nouveaux modèles pour l'étude du plus grand d'entre eux, la baleine bleue (Balaenoptera musculus), qui émet de très basses fréquences. Pour ce faire, nous avons enregistré un corpus inédit dans l'archipel de Humboldt au nord du Chili. Nos données révèlent un chant caractéristique de la baleine bleue 'chilienne', dont nous étudions la structure pulsée et l'évolution au cours des dernières décennies. Le classement en signal tonal ou non-tonal nous permet, en nous focalisant sur la fréquence fondamentale mise à jour, de quantifier la baisse en fréquence des chants et d'effectuer une comparaison des signaux au niveau mondial. Notre troisième contribution est une méthode de localisation mono-hydrophone basée sur des simulations de propagation par éléments spectraux. C'est à notre connaissance le premier modèle de ce type, implémenté en milliers d'heures de calcul haute performance. Nous concluons en soulignant l'intérêt des méthodes en bioacoustique comme moyen de suivi et de connaissance du milieu marin
Passive acoustic monitoring has a growing importance in marine mammals studies. This work is concerned with the largest of marine mammals, the blue whale (Balaenoptera musculus). We obtained a new corpus of acoustic data in the northern part of Chile, in the Humboldt archipelago. We show the presence of a song characteristic of the 'Chilean' blue whale, formerly described in southern Chile and Galapagos islands. Based on this sang type, we propose new methods of analysing and classifying pulsed sounds. Using the fundamental frequency thus obtained, we analyse the blue whale's sang, showing a general evolution of the frequency on a decadal scale. We also construct a method of mono­hydrophone source localisation based on high performance simulation of the acoustic wave field, by spectral elements methods. We conclude emphasizing on the importance of bioacoustic for monitoring the marine world
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Martins, Cristiane C. A. "Study of baleen whales’ ecology and interaction with maritime traffic activities to support management of a complex socio-ecological system." Thèse, 2012. http://hdl.handle.net/1866/10799.

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La gestion du milieu marin pour de multiples usages est une problématique de plus en plus en complexe. La création d’aires marines protégées (AMP) a été désignée comme étant une stratégie efficace afin de concilier la conservation avec les autres usages. Cependant, pour atteindre les objectifs de conservation, un plan de gestion bien défini de même qu’un programme de suivi efficace doivent être instaurés. En 1998, le parc marin du Saguenay–Saint-Laurent (PMSSL) a été créé afin de protéger plusieurs écosystèmes important de l’Estuaire du Saint-Laurent. Une industrie d’observation en mer de baleines en pleine croissance était déjà établie dans la région, qui est également traversé par une voie de navigation commerciale importante. Treize espèces de mammifères marins sont présentes dans la région, parmi lesquelles, quatre espèces de rorquals sont le centre d’intérêt du présent travail : le petit rorqual (Balaenoptera acutorostrata), le rorqual commun (Balaenoptera physalus), le rorqual à bosse (Megaptera novaeangliae) et le rorqual bleu (Balaenoptera musculus). La réduction des risques de collision et des perturbations du comportement susceptibles d’entrainer des conséquences physiologiques constitue un des enjeux majeures pour la conservation des baleines dans cette région. Avant de s’intéresser aux impacts du trafic maritime, des questions de base doivent être étudiées: Combien de baleines utilisent le secteur? Où sont les zones de fortes concentrations? Pour répondre à ces questions, des données d’échantillonnage par distance le long de transect linéaire sur une période de quatre ans (2006-2009) ont été utilisées pour estimer la densité et l’abondance et pour construire un modèle spatiale de la densité (MSD). Les espèces les plus abondantes sont le petit rorqual (45, 95% IC = 34-59) et le rorqual commun (24, 95% IC=18-34), suivi du rorqual bleu (3, 95% IC=2-5) et du rorqual à bosse (2, 95% IC=1-4). Les modèles additifs généralisés ont été utilisées afin de modéliser le nombre d’individus observé par espèce en fonction des variables environnementales. Les MSD ont permis l’identification des zones de concentration de chaque espèce à l’intérieur des limites de la portion de l’estuaire maritime du PMSSL et à valider les abondances estimées à partir des recensements systématiques. De plus, ils ont validé la pertinence de la zone de protection marine de l’estuaire du Saint-Laurent proposée (ZPMESL) pour la conservation du rorqual bleu, une espèce en voie de disparition. Un exercice d’extrapolation a également été effectué afin de prédire les habitats du rorqual bleu à l’extérieur de la zone d’échantillonnage. Les résultats ont montré une bonne superposition avec des jeux de données indépendants. Malgré la nature exploratoire de cet exercice et dans l’attente de meilleures informations, il pourrait servir de base de discussion pour l’élaboration de mesures de gestion afin d’augmenter la protection de l’espèce. Ensuite, les systèmes d’informations géographiques ont été utilisés afin de vérifier le degré de chevauchement entre la navigation commerciale et les résultats des MSD de chaque espèce et l’exercice d’extrapolation. Les analyses ont identifiées les zones de forte cooccurrence entre les navires et les rorquals. Ces résultats démontrent la pertinence des mesures de gestion récemment proposées et ont mené à une recommandation d’ajustement de l’actuel corridor de navigation afin de diminuer le risque de collision. Finalement, le chevauchement avec l’industrie d’observation de baleines a été caractérisé avec des données d’un échantillonnage à partir de points terrestres conduit de 2008 à 2010. Bien que toutes les espèces de rorquals aient été suivies, seulement les résultats concernant les rorquals bleus et les rorquals à bosses sont présentés ici. Pour les rorquals bleus, 14 heures de données d’observation ont été analysées. Les rorquals bleus étaient exposés aux bateaux (<1 km), principalement les zodiacs commerciaux, dans 74 % des intervalles de surface (IS) analysés. L’exposition continue était de 2 à 19 IS et le nombre moyen de bateaux à l’intérieur d’un rayon de 1 km était 2.3 (±2.7, max=14). Lorsqu’en observation de l’animal focal, tous les bateaux commerciaux ont utilisé la zone à l’intérieur de 400 m, enfreignant ainsi le règlement qui prescrit une distance de retrait minimale de 400 m dans le cas d’espèces en voie de disparition. De plus, la variance du taux respiratoire de chaque individu était corrélée avec le pourcentage d’exposition au bateaux (0.73, p<0.05) suggérant une modification comportementale susceptible d’entrainer des conséquences physiologiques. Bien que le rorqual à bosse n’ait pas un statut de conservation critique, sont comportements en fait une cible importante de l’industrie d’observation. Un total de 50.4 heures d’observation du rorqual à bosse a été analysé. Les rorquals à bosse étaient exposés aux bateaux, principalement aux zodiacs commerciaux, pendant 78.5% du temps d’observation. Le nombre moyen de bateaux dans un rayon de 1 km était de 1.9 (±2.3, max=22). L’exposition cumulative aux activités d’observation de baleines peut avoir des conséquences à long terme pour les rorquals. L’application du règlement et des mesures pour augmenter la sensibilisation et le respect de la règlementation actuelle sont nécessaires. Des suggestions pour améliorer la règlementation actuelle sont proposées. Ce travail présente pour la première fois des estimés d’abondance pour l’aire d’étude, améliore les informations disponibles sur les zones de fortes concentrations, donne un appui à l’établissement d’un plan de zonage adéquat à l’intérieur des limites du PMSSL et souligne l’importance de l’établissement de la ZPMESL proposée. Par sa revue compréhensive de la question du trafic maritime en lien avec les rorquals présents dans l’estuaire, cette étude fournit des informations précieuses pour la gestion de ce système socio-écologique complexe.
Management of the marine environment for multiple usages has become increasingly complex. The creation of Marine Protected Areas (MPAs) has been pointed out as a successful strategy for combining conservation with other uses. However, to attain conservation goals, a well-defined management plan and a robust monitoring program need to be set. In 1998, the Saguenay St. Lawrence Marine Park (SSLMP) was decreed to protect important ecosystems of the St. Lawrence River Estuary. A growing whale watching industry was already established in the area which is also crossed by an important shipping lane. Thirteen marine mammal species occur in the area, among them, four baleen species, which are the focus of the present work: minke whales (Balaenoptera acutorostrata), fin whales (Balaenoptera physalus), humpback whales (Megaptera novaeangliae) and the blue whales (Balaenoptera musculus). Whales’ protection in this area of intensive marine traffic is of concern due to a high collision probability and induced behavioral and physiological changes. Before addressing the effects of the marine traffic, some basic questions needed to be answered: How many baleen whales use the area? Where are their core areas? To answer that, line-transect distance-sampling data collected over four years (2006-2009) were used to estimate density and abundance and to build a spatial density model (SDM). The most abundant species were minke (45, 95% CI=34-59) and fin whales (24, 95% CI=18-34), followed by blue (3, 95% CI=2-5) and humpback whales (2, 95% CI=1-4). Generalized additive models were used to model each species count as a function of space and environmental variables. The SDM allowed the identification of each species core area within the marine portion of the SSLMP, and corroborated the abundance estimates derived from design-based methods. In addition, it corroborated the relevance of the proposed St. Lawrence Estuary Marine Protected (SLEMPA) Area to the conservation of essential habitats of the endangered blue whale. An extrapolation exercise was performed to predict blue whales’ habitats outside the surveyed area. Despite its exploratory nature, the results showed a good match with independent data sets and in the lack of better information could guide the discussion of management measures to enhance species’ protection. Next, Geographic Information System capabilities were used to verify the degree of overlap between the navigation corridor and the resulting SDM of each species and the extrapolation model. The analysis highlighted areas of important co-occurrence of whales and ships, corroborated the adequacy of recently proposed management measures and resulted in a recommendation of adjustment to the current shipping lane in order to decrease collision risk. Finally, the overlap with the whale watching industry was characterized with data from a land-based survey conducted from 2008 to 2010. Although all baleen whale species were tracked, here only results of blue and humpback whales were presented. For blue whales, data from 14 hours of observation were analyzed. Whales were exposed to boats, mainly commercial zodiacs, in 74% of their surface intervals (SI). Continuous exposure ranged from 2 to 19 SI and the mean number of boats within a 1 km radius was 2.3 (±2.7, max=14). A complete lack of compliance with the current whale watching regulations was observed. Additionally, individual blow rate variance was correlated with percentage of exposure to boats (0.73, p<0.05). Although humpback whales do not have a critical conservation status, their intrinsic behaviour makes them a major target to the industry. A total of 50.4 hours of humpback whale observation was analysed. Whales were exposed to boats, mainly commercial zodiacs, during 78.5% of the observation time. The mean number of boats within a 1 km radius was 1.9 (±2.3, max=22). The cumulative exposure to whale watching can have long-term consequences for whales. Law enforcement and measures to raise awareness and compliance to current regulations are urgently needed. Suggestions to improve the current regulation were provided. The present work presents the first abundance estimates for the study area, refines the available information on baleen whales core areas, provides support to the establishment of an adequate zoning plan within the SSLMP and stresses the relevance of the SLEMPA. In addition it provides an in depth overview of the marine traffic issue and provides valuable information to support management of this complex socio-ecological system.
Thesis written in co-mentorship with Robert Michaud.
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Book chapters on the topic "Baleines à bec – Observations"

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Leggett, A. J., and S. Zhang. "The BEC–BCS Crossover: Some History and Some General Observations." In The BCS-BEC Crossover and the Unitary Fermi Gas, 33–47. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-21978-8_2.

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Conference papers on the topic "Baleines à bec – Observations"

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Ainomae, Ahti, Tonu Trump, and Yannick Le Moullec. "Distributed Adaptive Largest Eigenvalue Detection with SNR Weighted Observations." In 2018 16th Biennial Baltic Electronics Conference (BEC). IEEE, 2018. http://dx.doi.org/10.1109/bec.2018.8600974.

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