La mise en place d'objectifs de conservation adéquats repose sur la définition d'états de référence appropriés pour la distribution et l'abondance des espèces. Cependant, l'étendue des impacts cumulés de l'homme sur les écosystèmes est aujourd'hui largement sous-estimée. Dans ce projet, je m'intéresse aux opportunités qu'offre l'utilisation de données historiques combinées à différentes méthodes analytiques pour définir ces états de référence ainsi qu'aux défis posés par ce type d'approche. Des données de présence ont été recueillies pour sept espèces de cétacés et trois espèces de pinnipèdes à partir de sources archéologiques, historiques et industrielles, révélant des réductions dans la distribution et l'abondance des espèces depuis la préhistoire à nos jours. Des modèles de distribution d'espèces ont été développés pour cinq espèces de cétacés, combinant des données de chasse baleinière du 19ème siècle à des variables environnementales afin d'estimer la distribution historique des espèces avant qu'elles n'aient été chassées. J'ai obtenu pour la baleine franche de l'Atlantique Nord (Eubalena glacialis) une estimation détaillée de sa distribution et de son abondance avant qu'elle ne soit exploitée, en extrapolant des connaissances sur la distribution et l'abondance d'une espèce congénérique, la baleine franche du Pacifique Nord (E. japonica). Ces résultats suggèrent que la baleine franche de l'Atlantique Nord occupe une portion réduite de sa distribution historique, et que son abondance actuelle ne représente qu'une infime portion (<5%) de son abondance passée. Plus généralement, ces résultats soulignent l'importance de considérer des données historiques pour comprendre le niveau d'impact par l'homme sur les espèces, évaluer leur niveau de déplétion et renseigner leur potentiel de rétablissement dans l'avenir. / Relevant baselines on the historical distribution and abundance of species are needed to support appropriate conservation targets for depleted species, but the full scale of cumulative human impacts on ecosystems is highly underestimated. In this project, I investigated the challenges and opportunities of combining historical data with analytical methods to improve these historical baselines. Occurrence data from archaeological, historical and industrial sources were reviewed for seven cetacean and three pinniped species, revealing range contractions and population depletions from prehistorical times to today. For five whale species, I used species distribution modelling to combine 19th Century whaling records with environmental data, to estimate pre-whaling distributions. For the highly depleted North Atlantic right whale, (Eubalaena glacialis), I obtained a detailed estimate of pre-whaling distribution and abundance by inferring from the historical distribution and abundance of its congeneric North Pacific right whale (E. japonica). These results suggest that the North Atlantic right whale occupies a small fraction of its historical range and that its current population represents <5% of its historical abundance, with implications for the management, monitoring and conservation targets of this species. More generally, these results emphasize the utility of considering historical data to understand the extent to which species have been impacted by humans, assess their current level of depletion, and inform the options available for their future recovery.

No description available.

Marine mammals play an important role in ecosystem stability. However, anthropogenic activity is compounding pressure on many already vulnerable populations. A potential consequence of anthropogenic disturbance is physiological stress, which can impact metabolism, immunity, and reproduction, especially if it occurs repeatedly. Previous studies on marine mammals have focused on acute stress, but the impacts of repeated stress are poorly understood. Due to its accessibility on land during haul-outs, the northern elephant seal (Mirounga angustirostris) is a good system in which to study the effects of stress in marine mammals. Stress stimulates the release of glucocorticoid hormones, primarily cortisol. Elevated cortisol is a good indicator of acute stress, but it is an unreliable proxy for chronic stress, and cortisol measurements alone do not provide information on the downstream physiological consequences of chronic stress. Therefore, additional biomarkers may provide a more comprehensive understanding of the effects of repeated stress on marine mammals. I examined two approaches for assessing stress in response to administration of the hormone that stimulates secretion of cortisol (adrenocorticotropic hormone; ACTH): a non-targeted proteomics approach using blood plasma and a targeted gene expression approach examining blubber expression of glucocorticoid receptor (GR) and two of its regulators, FKBP5 and KLF9. For the first approach, I used the highly sensitive LC-MS/MS technique to detect changes in circulating plasma proteins in juvenile seals in response to repeated ACTH administration. I identified changes in relative abundance of proteins of interest in the plasma proteome that included those with roles in lipid, iron, and redox homeostasis, cortisol and thyroid hormone transport, adipogenesis, oxidative stress, blood pressure regulation, vitamin and mineral transport, and innate immunity. I then measured blubber expression of GR and its regulator genes in blubber of adult female seals undergoing early and late molting to examine changes during different life-history stages in response to acute stress induced by ACTH administration. Using RT-qPCR, I found that GR expression decreased in blubber, while expression of FKBP5 increased, suggesting negative feedback at the tissue level which may reduce sensitivity to cortisol during key life-history stages, such as molting, which require fasting. These data provide insights into the resilience of marine mammals to acute stress and novel biomarkers that may be used to study the effects of prolonged stress in wildlife.

Marine mammals such as northern elephant seals (NES) routinely experience hypoxemia and ischemia-reperfusion events to many tissues during deep dives with no apparent adverse effects. Adaptations to diving include increased antioxidants and elevated oxygen storage capacity associated with high hemoprotein content in blood and muscle. Despite experiencing decreased oxygen tensions during diving, NES likely rely on the mobilization of large lipids stores and catabolism of fatty acids to provide energy to exercising muscle while diving. To identify potential regulatory mechanisms that may underly hypoxia and exercise tolerance in diving mammals, this study used system-wide approaches to characterize changes in genes and proteins in two metabolically active tissues (skeletal muscle and blubber) and whole blood of NES over development and in response to translocation. Specifically, this study profiled muscle and blood gene expression associated with regulation of oxidative stress and inflammatory pathways in weaned pups, juveniles, and adult NES as well as evaluated muscle and blubber transcriptomic and proteomic responses to swimming and diving in juvenile NES. I found that expression of genes associated with mitochondrial biogenesis (PGC1A, ESRRA, ESRRG), immune system activation (HMOX2, IL1B, NRF2, BVR, IL10), and protection from lipid peroxidation (GPX4, PRDX6, PRDX1, SIRT1) increased over postnatal development in muscle and whole blood of NES, providing a potential ontogenic mechanism for increasing diving capacity and hypoxia and ischemia-reperfusion tolerance. I also found that expression of genes and abundance of proteins associated with lipid transport (APOD, ABCA6, ABCA8, ABCA10, CD1E), lipid catabolism (ADIPOQ , ENPP6), and adipogenesis (DLK1, ADIRF,) increased, while those associated with insulin sensitivity and energy expenditure (APLN, VGF) decreased in response to swimming and diving in juvenile NES blubber and muscle, suggesting potential mechanisms for fuel provisioning to muscle during exercise in hypoxic conditions. Together, these data provide insights into gene activity in muscle, blubber, and blood cells that may provide hypoxia tolerance and regulate energy homeostasis and exercise performance during breath holds in diving mammals.

No description available.

Bottlenose dolphins of the Kvarnerić (NE Adriatic Sea) live in an area of increasing human impact, through tourism and small-scale fisheries. This thesis aimed to assess the status of the local population and to inform managers on factors affecting their distribution and abundance, using data from 1995-2003. Habitat modelling indicated a significant negative impact of proximity to the main ‘marine highway’ and to marine petrol stations. Evidence was found that dolphins may recently have reached a tolerance limit to the number of boats using the area and that they remember crowded areas from one year to the next. Dolphin presence was positively related to particular depths and trawling areas. Apparent adult survival rate was estimated to be significantly lower than for any other bottlenose dolphin population and first year calf survival was also low. A decreasing trend in fecundity rate was found. The population showed a considerable rate of non-random temporary emigration from the study area. The estimated size of the population was small and similar to two other European bottlenose dolphin populations (Moray Firth in Scotland and Shannon Estuary in Ireland). A significant decrease in abundance of about 39% from 1995 was estimated. PVA confirmed the importance of female adult survival to population viability and indicated that the current rate of human-induced mortality is unsustainable. Local extinction risk within three generations was estimated to be high (35%). Applying the IUCN Red List Criteria, the Kvarnerić population should be listed as Endangered under Criterion C and E. This study gives an important insight into the ecology of Adriatic bottlenose dolphins and indicates the need for a regionally and locally synergistic approach to conserve this population.

Over the past decades technological developments have both changed and increased human in influence on the marine environment. We now have greater potential than ever before to introduce disturbance and deplete marine resources. Two of the issues currently under public scrutiny are the exploitation of fish stocks worldwide and levels of anthropogenic noise in the marine environment. The aim of this thesis is to investigate and develop novel analyses and simulations to provide additional insight into some of the challenges facing the marine ecosystem today. These methodologies will improve the management of these risks to marine ecosystems. This thesis first addresses the issue of competition between humans and grey seals (Halichoerus grypus) for marine resources, providing compelling evidence that a substantial proportion of the sandeels consumed by grey seals in the North Sea are in fact H. lanceolatus, which is not commercially exploited, rather than the commercially important A. marinus. In addition, we present quantitative results regarding sources of bias when estimating the total biomass of sandeels consumed by grey seals. Secondly, we investigate spatially adaptive 2-dimensional smoothing to improve the prediction of both the presence and density of marine species, information that is often key in the management of marine ecosystems. Particularly, we demonstrate the benefits of such methods in the prediction of sandeel occurrence. Lastly this thesis provides a quantitative assessment of the protocols for real-time monitoring of marine mammal presence, which require that acoustic operations cease when an animal is detected within a certain distance (i.e. the &quot;monitoring zone&quot;) of the sound source. We assess monitoring zones of different sizes with regards to their effectiveness in reducing the risks of temporary and permanent damage to the animals' hearing, and demonstrate that a monitoring zone of 2 km is generally recommendable.

The topic of this master thesis is the international legal regulation of the protection of marine mammals. The thesis concentrates primarily on the analysis of the species based international law instruments for the protection of the individual marine mammal species. This thesis is divided into six chapters. The first chapter addresses the main principles of the international environmental law, which have the biggest influence on the protection of marine mammals (biodiversity protection, precautionary principle and sustainable development). The second chapter describes the regulation of fisheries, which is closely related to the protection of marine mammals. This part deals with the historical beginning of the international regulation of fisheries, the UN Convention on the Law of the Sea, the division of the sea areas, regulation of individual fish species and the regulation of fisheries after the UNCLOS. The particular instruments of protection of individual species of marine mammals except Cetaceans are described in the third chapter (i.e. polar bears, Pinnipeds and Sirenidae). The protection of Cetaceans is analyzed in detail in the fourth chapter. The protection of whales on the ground of International Whaling Commission is accented. This chapter describes also the standpoint of the whaling countries...

Thesis (S.M.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and the Woods Hole Oceanographic Institution), 2009. / Includes bibliographical references (p. 101-107). / Marine mammal whistle calls present an attractive medium for covert underwater communications. High quality models of the whistle calls are needed in order to synthesize natural-sounding whistles with embedded information. Since the whistle calls are composed of frequency modulated harmonic tones, they are best modeled as a weighted superposition of harmonically related sinusoids. Previous research with bottlenose dolphin whistle calls has produced synthetic whistles that sound too "clean" for use in a covert communications system. Due to the sensitivity of the human auditory system, watermarking schemes that slightly modify the fundamental frequency contour have good potential for producing natural-sounding whistles embedded with retrievable watermarks. Structured total least squares is used with linear prediction analysis to track the time-varying fundamental frequency and harmonic amplitude contours throughout a whistle call. Simulation and experimental results demonstrate the capability to accurately model bottlenose dolphin whistle calls and retrieve embedded information from watermarked synthetic whistle calls. Different fundamental frequency watermarking schemes are proposed based on their ability to produce natural sounding synthetic whistles and yield suitable watermark detection and retrieval. / by Jared Severson. / S.M.

Ao longo dos tempos, os cetáceos têm estado metaforicamente próximos à espécie humana o que tem revelado uma inter-relação ambígua, uma vez que podem evocar imagens de inteligência e mistério ao mesmo tempo em que servem como fonte de subsistência e de exploração econômica. Sem dúvida alguma, a relação positiva entre homens e cetáceos atingiu seu ápice na antiga civilização grega e prova disso são os registros históricos das lendas e mitos relacionados aos golfinhos. Por outro lado, sabe-se que a caça a baleia é uma atividade muito antiga praticada desde a pré-história por povos antigos. Os dias atuais ainda refletem a ambigüidade da relação homem/cetáceo. Contudo, as descobertas científicas das últimas décadas trouxeram a possibilidade de um relacionamento positivo com esses animais, especialmente no que se refere ao turismo de observação em contraposição à continuidade/retorno da caça comercial. Em vários lugares do mundo encontramos diferentes comunidades tradicionais que mantém um relacionamento de admiração e respeito com os cetáceos, gerando um conhecimento aprimorado sobre diferentes aspectos de sua biologia e ecologia. Sob as luzes interdisciplinares da etnociência, deu-se continuidade e ampliou-se o estudo das relações e conexões entre pescadores caiçaras tradicionais e as espécies de cetáceos ocorrentes ao longo do Complexo estuarino-lagunar de Cananéia. Os resultados indicam que os caiçaras são capazes de perceber e prever mudanças climáticas, classificar e localizar espacialmente organismos marinhos e elaborar complexas cadeias tróficas. Apresentam uma percepção acurada com relação à biologia e ecologia do boto Sotalia guianensis (CETACEA; DELPHINIDAE), especialmente em relação ao comportamento, hábitos alimentares e reprodutivos da espécie, e possuem um conhecimento generalizado sobre outros mamíferos aquáticos. A transmissão cultural desse conhecimento ocorre de forma vertical (entre gerações) e também de forma horizontal (dentro da mesma geração). A comunidade caiçara de Cananéia deve ser devidamente incorporada aos processos decisórios relacionados ao tema sócio-ambiental, bem como, nas tomadas de decisão relacionadas ao gerenciamento das atividades turísticas visando à promoção da prática de um turismo participativo e de base sustentável. Esse envolvimento deve ser planejado e avaliado de forma intensamente participativa, respeitando-se os critérios legislativos e também aqueles estabelecidos pelos próprios representantes dessas comunidades. As questões relacionadas à área sócio-ambiental devem ser tratadas de forma interdisciplinar com a finalidade de se compor um cenário cooperativo para a construção de propostas participativas que não criem condições de exclusão das comunidades, mas sim, as incorpore no processo de forma a se respeitar e valorizar os seus saberes e fazeres tradicionais. Novos modelos de propostas conservacionistas interdisciplinares devem ser construídos de forma a promover a inclusão sócio-ambiental das comunidades tradicionais, evitando assim, conflitos e má utilização de Unidades de Conservação. Respeitar o conhecimento e a cultura caiçara local torna-se fundamental para que se tenha a dimensão exata das estratégias de conservação das espécies e ecossistemas do Lagamar. / Throughout the years, cetaceans have been metaphorically close to humans, and this has revealed an ambiguous inter-relationship, since they may evoke images of intelligence and mystery at the same time they are sources of subsistence and economic exploration. Undoubtedly, the positive human-cetacean relation has peaked during the ancient Greek civilization, as proven by historical records of dolphin-related legends and myths. On the other hand, it is known that the whale hunting is a very old activity, practiced since the pre-history by ancient civilizations. Current days still reflects this ambiguity between human and cetaceans. However, the scientific discoveries of the last decades have brought a possibility of a positive relationship with these animals, especially about the whale watching in opposition to the continuance/return of the commercial hunting. It can be found in several places of the world traditional communities that keep an admiration and respect relationship with these animals, creating and improving knowledge about different aspects of their biology and ecology. Under the interdisciplinary lights of etnoscience, the continuity and enlargement of the study of the relations and conexions between traditional caiçaras fishermen and the cetaceans&#39; species that occurs in the &#34;Complexo Estuarino-Lagunar de Cananéia&#34; have been established. Our results show the ability of caiçaras to notice and anticipate climatological changes, classify and locate marine organisms and elaborate complex trofic chains. They have and accurate perception in relation to the biology and ecology of the estuarine dolphin, Sotalia guianensis (CETACEA; DELPHINIDAE), especially about their behavior, reproductive and feeding habits, and have also a general knowledge about other species of aquatic mammals. The transmission of cultural knowledge occurs in a vertical manner (between generations) and in a horizontal manner (in the same generation). The Cananéia&#39;s caiçara community must be properly incorporated to the resolution process related to environmental themes, such as in the decisions related to the management of touristic activities intending to promote participative and self-sustained tourism. This involvement must be planned and valued in a very participative way, respecting the legal rules and also, the ones established by the people that represents these communities. The questions related to the environmental area must be treated in an interdisciplinary way, aiming the construction of a cooperative scene, to build a participative proposal that don&#39;t excludes the communities, but keep them incorporated to the creation process, respecting and valorizing their traditional knowledge and actions. New models of interdisciplinary conservacionist proposals must be building, intending to promote the environmental inclusion of traditional communities, avoiding conflicts and bad uses of forest preserve. Keep the respect is fundamental to the local caiçara&#39;s knowledge and culture. That is the way to gain the exact dimension of the conservation strategies of Lagamar&#39;s species and ecosystem.