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1
Winn, Jeremy Paul. "Modeling Large Whale Entanglement Injuries: An Experimental Analysis of the Influence of Tissue Compliance, Line Tension, and Draw-Length on Epidermal Abrasion Resistance." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/WinnJP2006.pdf.
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Pinto, Sheldon James Dominick. "On the filtration mechanisms and oral anatomy of lunge-feeding baleen whales." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37849.
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Here we endeavoured to quantify the filtration mechanics of rorquals and the material properties of baleen “gums” (termed zwischensubstanz) by examining and testing the baleen of a fin whale (Balaenoptera physalus). It was hypothesized that fin whales use cross-flow filtration to filter krill from engulfed seawater such that krill and other debris do not become entangled in the baleen fringes. Cross-flow filtration was proposed as an alternate mechanism to dead-end sieving since it would create a highly concentrated suspension of krill inside the mouth (potentially at the oesophageal opening) and would also not require krill to contact the baleen, eliminating clogging and filtering efficiency losses.
We tested filtration mechanisms by placing a sixty-two centimetre section of baleen from a fin whale in a circular water tank and imitating the whale’s environment through various flow scenarios and setups. It was not conclusively determined whether cross-flow filtration is the mechanism used by fin whales, but a new mechanism was proposed called centripetal filtration in which two slugs of water spiral anteriorly on the left and right side of the whale’s oral cavity. Further examination of this proposed mechanism is required.
The material properties of the zwischensubstanz that holds baleen plates together and the development of baleen plates through this zwischensubstanz were also examined. Zwischensubstanz exhibits isotropic properties similar to soft rubber in compression with an average Young’s modulus of 2.56 ± 0.60 MPa and 44.4 ± 2.4% hysteresis when compressed at 0.5 Hz, as it appears to space the baleen plates and absorb stresses translated from the plates. Through this rubbery zwischensubstanz, the baleen plates develop from conical papillae to hard, keratinized plates. The zwischensubstanz forms a matrix around the papillae and is calcified and keratinized before exiting the zwischensubstanz as a fully developed plate.
The discoveries made here with regard to centripetal filtration and the properties of zwischensubstanz are preliminary attempts at quantifying baleen whale filtration and its associated feeding structures. Such work has been rare in the literature and there are many questions left to be answered by eager scientists with regard to the greatest biomechanical event in the world.
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Lysiak, Nadine Stewart J. "Investigating the migration and foraging ecology of North Atlantic right whales with stable isotope geochemistry of baleen and zooplankton." Restricted access (UM), 2008. http://libraries.maine.edu/gateway/oroauth.asp?file=orono/etheses/37803141.pdf.
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Risch, Denise [Verfasser]. "Baleen whale acoustic ecology with focus on minke whales (Balaenoptera acutorostrata) and reference to anthropogenic noise / Denise Risch." Kiel : Universitätsbibliothek Kiel, 2014. http://d-nb.info/1062535995/34.
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Marques, Fernanda F. C. "Baleen whale distributional patterns and the potential influence of biological and physical processes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/MQ36151.pdf.
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Woodward, Becky. "Locomotory Strategies, Dive Dynamics, and Functional Morphology of the Mysticetes: Using Morphometrics, Osteology, and DTAG Data to Compare Swim Performance in Four Species of Baleen Whales." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/WoodwardBX2006.pdf.
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Pangerc, Tanja. "Baleen whale acoustic presence around South Georgia." Thesis, University of East Anglia, 2010. https://ueaeprints.uea.ac.uk/19109/.
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Punt, A. E. "Management procedures for Cape hake and baleen whale resources: Part 1." Thesis, University of Cape Town, 1991. http://hdl.handle.net/11427/23366.
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Drake, Summer Elizabeth. "Sensory hairs in the bowhead whale (Cetacea, Mammalia)." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1406300822.
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Saloma, Anjara. "Humpback whales (Megaptera novaeangliae) mother-calf interactions." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS138.
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Chez les baleines à bosse (Megaptera novaeangliae), le maintien des liens sociaux entre les femelles et leurs nouveau-nés implique différentes modalités sensorielles telles que l'ouïe, le toucher et la vision. Si la communication acoustique chez les mâles chanteurs de cette espèce a été largement étudiée, les sons sociaux, en particulier ceux produits par les femelles et leurs nouveau-nés, ont été peu reportés. Cette étude décrit les sons sociaux présents dans les enregistrements acoustiques axés sur les groupes mère-baleineau et discute des vocalisations produites par les femelles et les baleineaux dans les interactions mère-jeune. En considérant les sons les plus fréquents de ce répertoire vocal, une analyse centrée sur la détermination de la source des sons de bass fréquence produits par la mère a été effectuée et des analyses ont été réalisées pour mettre en évidence l'individualité de certaines vocalisations appartenant à la mère et à son petit. Une description du contexte comportemental de leur production vocale a été réalisée et parallèlement, les profils de plongée des mères et de leurs nouveau-nés ont été décrits. En outre, les femelles et leurs petits passent beaucoup de temps à la surface de l'eau. Les mères sont souvent statiques à la surface tandis que les baleineaux évoluent autour d'elles. Cette étude est également consacrée à la compréhension de leurs comportements de surface, en tenant compte des comportements initiés par les baleineaux. Des séries d’analyses ont été réalisées pour déterminer si les baleineaux présentaient des comportements de latéralisation par rapport à leur mère. Enfin, en utilisant la méthode de photogrammétrie, les tailles des femelles et des nouveau-nés ont été mesurées, ainsi que l'espace utilisée par les baleineaux autour de leur mère<br>In humpback whales (Megaptera novaeangliae), maintaining social bonds between females and their newborns involves different sensory modalities such as hearing, touching and vision. While acoustic communication in male singers of this species has been extensively studied, social sounds, especially those produced by the females and their newborns have been poorly documented. This study describes the social sounds present in acoustic recordings focused on mother-calf groups and discusses the vocalizations used by females and calves in mother-offspring interactions. By considering the most frequent sounds from their vocal repertoire, an analysis focused on the determination of the source of the low-frequency sounds produced by the mother have been carried out and analyses were performed to investigate the individuality of some vocalizations belonging to the mothers and the calves. A description of the behavioural context of their vocal production was performed and the diving profiles of mother-calf pairs were described. Moreover, females with their calves spend a lot of time on the water surface. Mothers are often static at the surface while calves move around them. This study is also dedicated to the understanding of their surface behaviours, considering the behaviours initiated by calves. A series of analyses were carried out to determine whether calves exhibited lateralization behaviours in relation to their mothers. Finally, by using photogrammetry method, mother-calf lengths were measured, and calves spatial range around their mothers was investigated
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Kennedy, Amy. "Satellite telemetry and humpback whales : A tool for determining the habitat use, distribution and behavior of an endangered large whale species." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00989629.
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This dissertation has been prepared in manuscript format and contains four individual papers. Each paper/chapter is formatted for the journal to which it has been, or will be, submitted. In the first manuscript, "From Whaling to Tagging: The evolution of knowledge regarding humpback whales in their North Atlantic breeding grounds", I describe the evolution of humpback whale research from the days of Yankee whaling to the most recent satellite telemetry project in the West Indies breeding grounds. The humpback whales that over-winter in the West Indies are part of one of the most heavily studied whale populations in the world; projects conducted in this area have served as models for humpback whale research world-wide. This manuscript will be submitted for publication in Mammal Review in 2014. In my second manuscript, "Local and migratory movements of humpback whales satellite tracked in the North Atlantic Ocean", I report the results of a satellite telemetry project that was conducted in the winters of 2008 through 2012 in the breeding areas of Silver Bank (Dominican Republic) and Guadeloupe (French West Indies). The results from this project add a level of detail to the current knowledge about North Atlantic humpback whale habitat use, migration, and population structure that could not be obtained without current satellite tagging technology. This paper has been reviewed and accepted for publication by the Canadian Journal of Zoology and will be published by November, 2013 ii In my third manuscript, "Individual variation in movements of humpback whales satellite tracked in the eastern Aleutian Islands and Bering Sea", I report the results from a satellite telemetry project conducted off Dutch Harbor, (Alaska, USA) in the summers of 2007 through 2011. Satellite telemetry from this project showed the fine-scale use of foraging habitat in a North Pacific feeding ground. Additionally, a long-distance, within-season travel event was recorded in 2010, prompting speculation about the humpback population structure throughout the Bering Sea. This manuscript has been reviewed and accepted for publication by Endangered Species Research and will be published by November, 2013. In the fourth manuscript, "Assessing implantable satellite tag extrusion using light sensors", I report the results of a novel approach for remotely quantifying tag rejection; the use of tag-mounted light sensors to indicate extrusion rate. The data for this paper were collected during a 2011 follow-up study aimed at assessing the behavioral and physiological responses of Gulf of Maine humpback whales to current tagging methods. Tag diagnostic technology like this, while still being developed, could significantly improve future telemetry work by updating tag design and placement methods to increase overall project efficiency. This paper has been accepted as a poster presentation at the 20th Biennial Conference on the Biology of Marine Mammals (December 2013, Dunedin New Zealand). It will be updated with the results from the 2013 Gulf of Maine tagging field season and submitted to a peer reviewed journal in 2014.
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Thomas, T. A. "Behaviour and habitat selection of bowhead whales (Balaena mysticetus) in Northern Foxe Basin, Nunavut." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0023/MQ51810.pdf.
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Thomas, T. A. "Behaviour and habitat selection of bowhead whales (Balaena mysticetus) in Northern Foxe Basin, Nunavut." Ottawa : National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.nlc-bnc.ca/obj/s4/f2/dsk1/tape2/PQDD%5F0023/MQ51810.pdf.
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Matthews, Cory. "Longitudinal Diet Studies of Arctic Whales." Marine Biological Association of the United Kingdom, 2013. http://hdl.handle.net/1993/30149.
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An animal’s foraging ecology can vary over a range of temporal scales, mirroring seasonal and longer term changes in prey availability, as well as ontogenetic shifts in diet and distribution. Obtaining individual-based, longitudinal diet information through direct observation, however, is logistically challenging for marine mammals that pursue and consume prey underwater, and are often widely distributed. Isotopic profiling along continuously growing tissues like teeth and baleen, which archive dietary inputs at the time of growth in their stable isotope composition, allows for chronological dietary reconstructions over multi-year timespans. This thesis reports longitudinal diet studies of three Arctic whale species, killer whales (Orcinus orca), bowhead whales (Balaena mysticetus) and beluga whales (Delphinapterus leucas), derived from serial isotopic measurements along teeth and baleen. Study objectives varied by species, but general goals were to characterize seasonal, ontogenetic, and/or individual diet variation.
Results revealed similar trophic-level diet, but regional spatial separation, among eastern Canadian Arctic/Northwest Atlantic killer whales. However, isotope and tooth wear differences between two individuals and the rest of the sampled whales suggested potential specialisation on sharks, while the other whales likely had diets comprising marine mammals. Cyclic isotopic variation along Eastern Canada-West Greenland bowhead whale baleen was consistent with year-round foraging, although at a reduced rate during winter. Resting zooplankton could be an important food resource outside of periods of peak productivity, and accessibility likely drives winter habitat selection. Isotopic cycling did not differ between female and male bowheads, or among age classes, indicating similar seasonal foraging patterns despite reported spatial segregation throughout their summer range. Individual beluga whales from three eastern Canadian Arctic populations varied in timing of ontogenetic diet shifts (i.e. weaning age), as well as overall trophic position, which could reflect size-specific energetic requirements and foraging capabilities. Population-specific beluga whale diet trends over a period of several decades likely reflected climate-related expansions of southern forage fish. Collectively, findings of seasonal, ontogenetic, and/or individual diet variation contribute a greater understanding of intrapopulation variation in foraging ecology of these species, and of large-scale structuring of Arctic marine ecosystems.
15
Huebinger, Ryan Michael. "Genetic relationships and evolutionary history of extant Bowhead whale populations, Balaena mysticetus." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1514.
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Gao, Yingxue. "Detection of Whale Acoustic Signals in the Northern Gulf of Mexico LADC-GEMM Database." ScholarWorks@UNO, 2019. https://scholarworks.uno.edu/td/2692.
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Low-pass Fourier filter, wavelet filter, as well as matched filter detection methods were used to detect baleen whale signals in northern Gulf of Mexico data collected by the Littoral Acoustic Demonstration Center (LADC) consortium. Some potential low frequency signals appeared on the matched filter output figure. The shape of the signals is in line with one of the typical signal shapes of fin whales--vertical down-sweeps with 18s-time interval. Another shape of the signals is in line with one of the call type shapes of Bryde's whales--down-sweeps with 7s-time interval. A high-pass Fourier filter was also used to find toothed whale high frequency sounds in the Gulf of Mexico data. The sounds featuring click trains and codas belonging to sperm whales have been clearly identified.
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Souza, Shirley Pacheco de. "Etnoecologia de cetaceos em comunidades de pescadores de São Sebastião, São Paulo." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315744.
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Previous issue date: 2007<br>Resumo: A Etnobiologia estuda as interações entre populações humanas e recursos naturais, enfocando a percepção e o conhecimento humano sobre os recursos naturais, a forma como estes são utilizados e as práticas de manejo desenvolvidas pelas sociedades. O conhecimento ecológico local (LEK, de 'local ecological knowlegde¿) tem sido muito útil na elaboração de sistemas de co-manejo envolvendo comunidades locais, instituições do governo e cientistas. Pesquisas sobre o conhecimento dos pescadores em relação à ecologia de baleias e golfinhos iniciaram-se no Brasil na década passada. Os principais objetivos deste estudo são registrar e avaliar o conhecimento dos pescadores de São Sebastião, litoral paulista, em relação à etnotaxonomia (classificação e nomenclatura) de cetáceos, bem como sobre a etnoecologia destes animais obtendo informações sobre áreas de ocorrência, habitat, sazonalidade, dieta, tamanho de grupo, reprodução, predadores e interações com a pesca. Os resultados demonstraram que os pescadores estudados percebem os cetáceos em função de sua saliência morfológica e cultural. As espécies mais reconhecidas e nomeadas por eles foram as de maior tamanho (Eubalaena australis, Tursiops truncatus), as acidentalmente capturadas em redes de espera (Pontoporia blainvillei, Sotalia guianensis) e as mais veiculadas em programas de televisão (Megaptera novaeangliae, Orcinus orca). Encontramos uma alta concordância entre o LEK dos pescadores estudados sobre a ecologia dos cetáceos, o conhecimento de pescadores de outras comunidades do sul e sudeste brasileiro, dados obtidos de pesquisas locais e da literatura científica. Isto demonstra que o conhecimento dos pescadores pode ser útil para a conservação dos cetáceos, especialmente das espécies pouco conhecidas, sugerindo novas linhas de pesquisa e apontando áreas críticas em relação à captura acidental destes animais. Além disto, os pescadores podem contribuir de forma valiosa na elaboração de estratégias alternativas em relação ao uso de redes de pesca, ao passo que sua participação em projetos e planos de manejo pode ser uma forma de valorização da cultura local<br>Abstract: Ethnobiology, a branch of Human Ecology, is the study of the interactions between human population and natural resources, concerning human perception, knowledge, resource uses and management. Local ecological knowledge (LEK) has been empirically built by several human societies and transmitted through generations, shaping their culture. LEK has been especially useful
to design systems of co-management involving local people, government institutions and scientists. Surveys on fishers¿ knowledge about cetaceans¿ ecology are relatively scarce around the world and in Brazil they have begun in the last decade. The main objectives of this study are to record and to evaluate the knowledge of the fishers from São Sebastião, in relation to cetaceans¿ folk taxonomy
and bio-ecological aspects, recording their information about classification, nomenclature, occurrence areas, habitat, seasonality, diet, group size, reproduction, predators and interactions with fisheries. Our results showed that fishers¿ perception about cetaceans was highly influenced by phenotypic and cultural salience of the whales and dolphins. The most recognized and cited species were those of greater size (Eubalaena australis, Tursiops truncatus), the most frequently caught ones (P. blainvillei and S. guianensis) and the most exposed by media (M. novaeangliae and O. orca). The high concordance among the LEK of the fishers from São Sebastião on cetaceans, the knowledge of fishers from other communities of southern and southeastern Brazil, data obtained by local researchers and from literature indicates that fishers¿ knowledge could contribute to cetacean¿s conservation, especially in relation to the less studied cetacean¿s species, pointing out new lines of investigation as well as determining fishing grounds where incidental capture of cetaceans are more critical in the studied areas and indicating possible changes in gillnets operations in order to reduce cetaceans catches. Besides, fishers¿ participation in such researches and co-management plans can be a way to revive and valorize their local culture<br>Mestrado<br>Ecologia<br>Mestre em Ecologia
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Bass, Joanna. "Variations in gray whale feeding behaviour in the presence of whale-watching vessels in Clayoquot Sound, 1993-1995." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq52752.pdf.
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Lesnau, Giuliano Gustavo. "Anatomia do Complexo Valvar Atrioventricular Cardíaco Esquerdo da Baleia Minke (Balaenoptera acutorostrata Lacépède, 1804)." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-07092002-162525/.
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Alguns aspectos funcionais do aparelho circulatório da baleia têm sido objeto de importantes relatos na literatura, destacando a acentuada bradicardia que ocorre durante o mergulho. Entretanto, existem poucas informações relativas à morfologia dos seus órgãos circulatórios, principalmente os componentes do complexo valvar cardíaco. Este trabalho tem como objetivo, abordar a morfologia macroscópica da valva atrioventricular esquerda da Baleia Minke, abrangendo também, os músculos papilares e as cordas tendíneas. Foram estudados os componentes anatômicos do complexo valvar atrioventricular esquerdo em onze corações de Baleias Minke (Balaenoptera acutorostrata). Esses órgãos foram obtidos no ano de 1980, quando ainda era permitida a caça desses animais no Brasil, no Porto de Cabedelo, Estado da Paraíba. Desde então são mantidos em solução aquosa de formol a 10%, no Laboratório de Anatomia da FMVZ/USP. Fez-se uma abordagem da valva atrioventricular esquerda pelo afastamento, após incisão, da parede direita do ventrículo esquerdo, verificando-se que o coração da baleia Minke se assemelha em sua morfologia ao coração de mamíferos terrestres, apresentando um mínimo de quatro cúspides. A cúspide septal é maior que a parietal. Como nas demais espécies, as cúspides permitem o balonamento durante a sístole ventricular. A cúspide com maior área por corda tendínea é a septal. O complexo valvar atrioventricular esquerdo apresenta feixes compactos de cordas tendíneas, reduzindo o volume de componentes dentro da cavidade ventricular. Caracterizaram-se quatro tipos morfológicos de cordas tendíneas, caracterizadas como dos tipos I, II, III, IV e comissurais. O músculo papilar subatrial é o mais proeminente. A baleia pode apresentar, além dos músculos papilares subatrial e subauricular, um músculo papilar acessório.<br>A few information exist in the literature relative to the morphology of the circulatory organs of the whale, especially concerning the valvar complex of the heart. It tried to approach in this work, the macroscopic anatomy of the left atrioventricular valve of the whale Minke, as well as the musculi papillaris and Chordae tendineae. It was studied the anatomical components of eleven hearts of the Minke whales. Those organs were obtained in 1980, in the port of Cabedelo - Paraíba - Brazil, when the hunt of those animals was still allowed in Brazil. Those hearts are maintained in aqueous solution of formol at 10%, in the laboratory of Veterinary Anatomy of FMVZ/USP. Do Made himself then the access for the left atrioventricular valve, moving away the wall right ventricular of the cardiac wall by means of magnet incision in \" V \". The analysis of those hearts demonstrated that : the morphology of heart of the Minke whales is similar to the other terrestrial mammals, presenting a minimum of four leaflets. The septal leaflet is larger than to the parietal leaflet. As in the other species, the leaflets balloons during the ventricular systole. The leaflet with larger area for Chordae tendineae is the septal leaflet. The left atrioventricular valvar complex of the whale, presents bunches of strings compact tendineae, reducing the volume of components inside of the cavity ventricular. There is also, strings tendíneas classifieds as I, II, III IV and comissural types. The subatrial papilar muscle is the most prominent. The whale can present, besides the subatrial and subauricular muscles, one accessory papilar muscle.
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Hunter, Devra Denise. "Did bowhead whales (Balaena mysticetus) from the Bering-Chukchi-Beaufort Seas undergo a genetic bottleneck? A test using nuclear microsatellite loci." Thesis, Texas A&M University, 2005. http://hdl.handle.net/1969.1/2648.
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This study reexamines the nuclear microsatellite analysis by Rooney et al. (1999a) of Bering-Chukchi-Beaufort Seas bowhead whales (Balaena mysticetus) to determine if this population underwent a genetic bottleneck as a result of 19th and early 20th Century commercial whaling. This investigation used more accurate laboratory techniques to score alleles, had a larger sample size that was divided into two groups (mainland Alaska and St. Lawrence Island (SLI)), and used a moderately different set of microsatellite loci which are more variable and thus, more informative. The results corroborate the findings of Rooney et al. (1999a) for mainland Alaska showing no evidence of a genetic bottleneck. However, the SLI data analyses provide conflicting conclusions. The Wilcoxon test is significant for a heterozygote excess (p = 0.042) suggesting that a genetic bottleneck has occurred. This is not substantiated by the exact tests of each locus or the table-wide sign test. There is a possibility that a bottleneck has occurred, but due to the small sample size this is not a definitive conclusion and warrants reanalysis with a larger sample size.
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Fernandes, Deborah Pinto. "Spatial distribution of humpback whale singers in the abrolhos bank, BA, Brazil." PROGRAMA DE P?S-GRADUA??O EM PSICOBIOLOGIA, 2014. https://repositorio.ufrn.br/jspui/handle/123456789/22738.
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Previous issue date: 2014-03-31<br>Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)<br>Mam?feros marinhos formam um grupo bastante diversificado, incluindo cet?ceos, sir?nios, pin?pedes e carn?voros, como lontras e ursos polares. Estudos sobre a distribui??o e abund?ncia de mam?feros marinhos s?o de grande import?ncia para fins de conserva??o e manejo. Esses s?o animais que passam toda ou a maior parte da vida no ambiente aqu?tico e dependem de diversos fatores, como distribui??o de recursos alimentares, batimetria, distribui??o de parceiros, entre outros para sobreviver. Dentre todos os mam?feros marinhos, a baleia jubarte ? uma das esp?cies mais estudadas. A jubarte ? conhecida por produzir longas sequ?ncias padronizadas de sons conhecidas como "canto", sendo a ac?stica uma das principais formas de comunica??o no meio aqu?tico. Este trabalho tem como objetivo (1) fornece uma revis?o da literatura dispon?vel sobre o estudo da distribui??o de mam?feros marinhos utilizando m?todos ac?sticos e/ou visuais nos ?ltimos dez anos para identificar quais m?todos e t?cnicas t?m sido mais utilizados no campo; (2) prever a distribui??o de grupos de baleia jubarte vocalmente ativos em rela??o a vari?veis ambientais e sociais no entorno do Arquip?lago dos Abrolhos; e, (3) verificar a exist?ncia de sobreposi??es entre a rota utilizada pelos barcos de turismo e machos cantores no entorno do Arquip?lago dos Abrolhos, ?reas onde possa haver potenciais intera??es espaciais e ac?sticas. Atrav?s da revis?o de literatura no cap?tulo1, encontramos que, apesar do uso de monitoramento ac?stico passivo estar se tornando mais econ?mico e acess?vel nos ?ltimos anos, os m?todos mais usados para estudar distribui??o de mam?feros marinhos s?o visuais. Ao responder um question?rio sobre o m?todo utilizado, a maioria dos pesquisadores tenderam a escolher o m?todo visual por estarem inseridos em projetos maiores com outros focos. No segundo cap?tulo, foi feita uma regress?o log?stica utilizando profundidade, dist?ncia a um buffer ao redor das ilhas de Abrolhos (0,5 mn), dist?ncia a corais, tamanho de grupo e presen?a de filhote para prever atividade vocal. O modelo que melhor previu que grupos de baleias jubartes estariam vocalmente ativos quando n?o houver filhote presente no grupo (B = 1,234, Wald = 16,016, p < ,01), estiverem distantes de corais (B = ,403, Wald = 4,263, p < ,05) e em ?reas mais profundas (B = ,079, Wald = 3,460, p > ,05). Finalmente, no terceiro cap?tulo, realizamos an?lises espaciais que resultaram em mapas de densidade de grupos vocalmente ativos de baleias jubarte e de embarca??es de turismo. Encontramos que as ?reas de maior densidade de cantores coincide com ?reas de maior densidade de embarca??es. Tais ?reas foram classificadas como alto risco para a comunica??o da esp?cie na ?rea amostrada. Investigar as prefer?ncias de habitat das baleias jubarte para atividade vocal com base em caracter?sticas ambientais e composi??o de grupo ? essencial para o estabelecimento de ?reas de manejo espa?o-temporal com o objetivo de garantir uma comunica??o ac?stica adequada, t?o importante em ?reas de reprodu??o. N?s tamb?m fornecemos resultados que enfatizam a necessidade de p?r em pr?tica planos de manejo adaptativo que considerem fatores que podem ser importantes para a conserva??o e manejo da baleia jubarte.<br>Mam?feros marinhos formam um grupo bastante diversificado, incluindo cet?ceos, sir?nios, pin?pedes e carn?voros, como lontras e ursos polares. Estudos sobre a distribui??o e abund?ncia de mam?feros marinhos s?o de grande import?ncia para fins de conserva??o e manejo. Esses s?o animais que passam toda ou a maior parte da vida no ambiente aqu?tico e dependem de diversos fatores, como distribui??o de recursos alimentares, batimetria, distribui??o de parceiros, entre outros para sobreviver. Dentre todos os mam?feros marinhos, a baleia jubarte ? uma das esp?cies mais estudadas. A jubarte ? conhecida por produzir longas sequ?ncias padronizadas de sons conhecidas como "canto", sendo a ac?stica uma das principais formas de comunica??o no meio aqu?tico. Este trabalho tem como objetivo (1) fornece uma revis?o da literatura dispon?vel sobre o estudo da distribui??o de mam?feros marinhos utilizando m?todos ac?sticos e/ou visuais nos ?ltimos dez anos para identificar quais m?todos e t?cnicas t?m sido mais utilizados no campo; (2) prever a distribui??o de grupos de baleia jubarte vocalmente ativos em rela??o a vari?veis ambientais e sociais no entorno do Arquip?lago dos Abrolhos; e, (3) verificar a exist?ncia de sobreposi??es entre a rota utilizada pelos barcos de turismo e machos cantores no entorno do Arquip?lago dos Abrolhos, ?reas onde possa haver potenciais intera??es espaciais e ac?sticas. Atrav?s da revis?o de literatura no cap?tulo1, encontramos que, apesar do uso de monitoramento ac?stico passivo estar se tornando mais econ?mico e acess?vel nos ?ltimos anos, os m?todos mais usados para estudar distribui??o de mam?feros marinhos s?o visuais. Ao responder um question?rio sobre o m?todo utilizado, a maioria dos pesquisadores tenderam a escolher o m?todo visual por estarem inseridos em projetos maiores com outros focos. No segundo cap?tulo, foi feita uma regress?o log?stica utilizando profundidade, dist?ncia a um buffer ao redor das ilhas de Abrolhos (0,5 mn), dist?ncia a corais, tamanho de grupo e presen?a de filhote para prever atividade vocal. O modelo que melhor previu que grupos de baleias jubartes estariam vocalmente ativos quando n?o houver filhote presente no grupo (B = 1,234, Wald = 16,016, p < ,01), estiverem distantes de corais (B = ,403, Wald = 4,263, p < ,05) e em ?reas mais profundas (B = ,079, Wald = 3,460, p > ,05). Finalmente, no terceiro cap?tulo, realizamos an?lises espaciais que resultaram em mapas de densidade de grupos vocalmente ativos de baleias jubarte e de embarca??es de turismo. Encontramos que as ?reas de maior densidade de cantores coincide com ?reas de maior densidade de embarca??es. Tais ?reas foram classificadas como alto risco para a comunica??o da esp?cie na ?rea amostrada. Investigar as prefer?ncias de habitat das baleias jubarte para atividade vocal com base em caracter?sticas ambientais e composi??o de grupo ? essencial para o estabelecimento de ?reas de manejo espa?o-temporal com o objetivo de garantir uma comunica??o ac?stica adequada, t?o importante em ?reas de reprodu??o. N?s tamb?m fornecemos resultados que enfatizam a necessidade de p?r em pr?tica planos de manejo adaptativo que considerem fatores que podem ser importantes para a conserva??o e manejo da baleia jubarte.
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Ball, Hope C. "Metabolic Activity in a Non-Model System: Leptin and Lipolysis in Bowhead (Balaena Mysticetus) and Beluga (Delphinapterus Leucas) Whale." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1373972573.
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Bisi, Tatiana Lemos. "Comportamento de filhotes de baleia jubarte, Megaptera novaeangliae, na região ao redor do Arquipélago dos Abrolhos, Bahia (Brasil)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-20082007-112756/.
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A fim de caracterizar o comportamento de filhotes de baleia jubarte, este estudo foi conduzido ao redor do Arquipélago dos Abrolhos, um importante sítio de nascimento e cria da espécie no Brasil. Foram investigados aspectos do desenvolvimento comportamental dos filhotes, diferenças comportamentais entre filhotes nascidos em diferentes temporadas reprodutivas e, também, a influência da presença de um escorte no comportamento dos filhotes. Os dados foram coletados entre os anos de 1998 a 2004, entre os meses de julho a novembro, a partir de um ponto fixo de observação no topo da Ilha de Santa Bárbara, no Arquipélago dos Abrolhos. O método utilizado foi o de amostragem de animal focal, com registro de todos os eventos e estados comportamentais realizados pelos filhotes, com o auxilio de um teodolito. 207 observações focais foram analisadas, totalizando 313,65 horas de amostragem. Os filhotes apresentaram um repertório comportamental bastante diverso e com uma grande variação quanto à taxa de ocorrência. Os eventos mais freqüentes foram ARQUEAMENTO DO PEDÚNCULO, SALTO, EXPOSIÇÃO DE UM LOBO DA CAUDAL e BATIDA DE CAUDAL; os poucos freqüentes ou raros foram SLASH DE CAUDAL, BARRIGA PARA CIMA, ACENANDO e ALONGAMENTO DO PEDÚNCULO. Entre os estados comportamentais, os filhotes permaneceram a maior parte do tempo em NATAÇÃO, sendo observado em média 42,21% do tempo. MILLING foi o segundo estado mais freqüente (média: 29,86%), seguido de REPOUSO (média: 20,91%) e ATIVO (média: 7,02%). A alta freqüência de ocorrência de alguns eventos e o tempo gasto em NATAÇÃO sugerem a importância desses comportamentos no desenvolvimento da coordenação e aptidão motora, fortalecimento da musculatura e melhora da resistência nos filhotes. Dessa maneira, os filhotes desenvolvem habilidades necessárias para interações sociais futuras e reprodução e, também, para necessidades do momento, como o desenvolvimento da relação com a mãe, amamentação e preparação para a migração. A análise do comportamento dos filhotes nas três fases da temporada reprodutiva mostrou que os filhotes aumentaram a taxa de ocorrência dos eventos ARQUEAMENTO DO PEDÚNCULO, EXPOSIÇÃO DE CABEÇA, BATIDA DE CABEÇA, EXPOSIÇÃO DE UM LOBO DA CAUDAL e EXPOSIÇÃO DE PEITORAL. Entretanto, não foi possível identificar estágios de desenvolvimento específicos. Dez dos 18 eventos comportamentais apresentaram diferenças na taxa de ocorrência entre filhotes de temporadas distintas, assim como a proporção do tempo gasto em REPOUSO pelos filhotes foi diferente. Apesar destas diferenças observadas entre alguns anos, não foi identificado um padrão temporal. Na presença de um escorte o comportamento dos filhotes mudou: a taxa de ocorrência de ARQUEAMENTO DO PEDÚNCULO, EXPOSIÇÃO DE CABEÇA e COLO foi significativamente menor. Adicionalmente, os filhotes permaneceram mais tempo em NATAÇÃO e menos tempo em REPOUSO do que quando estavam acompanhados apenas de suas mães. Alguns trabalhos sugerem que a presença de um escorte pode proporcionar proteção ao filhote, porém, diante das alterações comportamentais observadas, e do aumento da velocidade média de natação, a presença do escorte parece não trazer benefícios, pelo contrário, parece ter um efeito negativo para o filhote, ao menos em termos energéticos.<br>To characterize the behavior of humpback whales calves, a study was conduct around Abrolhos Archipelago, an important nursing area for the species in Brazil. It was investigated aspects of the behavioral development of calves, behavioral differences between calves of different breeding seasons and also the effects of the presence of one escort in the behavior of calves. The data were collected from 1998 to 2004, through the months of July to November, from a land-base station on the top of Santa Barbara Island at the Abrolhos Archipelago. The chosen method was animal focal sampling, with record of all behavioral events and state occurrences, using a theodolite. A total of 207 focal observations were analyzed, comprising 313.65 hours of sampling. Humpback whales calves exhibit a very diverse behavioral repertoire, with a strong variation in the occurrence rate. More frequent events were PEDUNCLE ARCH, BREACH, EXPOSITION OF HALF OF THE FLUKE and TAIL SLAP; and the less frequent were TAIL SLASH, BELLY-UP, TAIL WAVE and PEDUNCLE ELONGATION. Among the behavioral states, calves remained more time SWIMMING (mean: 42.21%). MILLING was the second most frequent state (mean: 29.86%), followed by RESTING (mean: 20.91%) and ACTIVE was the least frequent (mean: 7.02%). The high frequency of occurrence of some behavioral events as well as the high proportion of time SWIMMING suggest that these behaviors are important to the development of coordination and motor ability and also to muscle strengthening. In this way, the calves can develop abilities needed to future social interactions and reproduction, but also to current needs, as in the development of the relationship with its mother, for nursing and for preparing to migration. There was a significant effect of phase of the season on rate of occurrence of PEDUNCLE ARCH, HEAD EXPOSITION, HEAD SLAP, EXPOSITION OF HALF OF THE FLUKE and PECTORAL EXPOSITION. However it was not possible to identify a specific development stage. Ten of 18 behavioral events showed variation in the rate of occurrence along the seven breeding seasons studied, also the proportion of time RESTING state showed a significant difference among seasons. Despite the observed differences among some years, they did not show any pattern. In the presence of one escort the behavior of calves changed. The rate of occurrence of PEDUNCLE ARCH, HEAD EXPOSITION and LAP was significant lower. Besides, calves remained more time SWIMMING and less time RESTING than when calves were only accompanied with their mothers. Studies suggest distinct functions to escorts, including provide protection to calves. However in face of the behavioral changes and increase in speed of swimming, the presence of one escort seems not to be an advantage, on the contrary seems to have a negative effect to the calf, at least in the energetic demand.
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Sensor, Jennifer Dawn. "HEARING AND AGE ESTIMATION IN TWO SPECIES OF ARCTIC WHALE." Kent State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=kent1512125887991219.
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Lucas, Joan Manel Alfaro. "Faunal composition and community structure of the world\'s deepest whale-fall community: shedding light on the ecological role of Osedax (Polychaeta: Siboglinidae) and whale-fall biogeography." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-20032016-201739/.
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This study aims to describe the faunal composition and community structure of the world\'s deepest whale fall and the first found in the South Atlantic Ocean. This discovery adds very important data on the poorly known whale-fall biogeography and provides new insights on the ecological role of the \"bone-eating\" worm Osedax (Polychaeta: Siboglinidae) on associated biota. The whale fall was serendipitously found in April 24th, 2013 at the base of São Paulo Ridge at 4204 m depth in the SW Atlantic Ocean using the HOV Shinkai 6500 during the Brazil-Japan joint Iatá-Piúna Oceanographic Expedition on board RV Yokosuka (Japan Agency for Marine-Earth Science and Technology, JAMSTEC). Detailed video surveys of the carcass were made using high-definition video cameras. Vertebrae, surrounding sediments and fauna were also collected using the submersible manipulators and a slurp gun. The partial skeleton belonged to an Antarctic Minke whale, Balaenoptera bonaerensis, and was composed of nine caudal vertebrae, whose degradation state suggests it was on the bottom for at least 5 years. Most of the 41 invertebrate species found are new to science, with ca. 12% of the genera shared with NE Pacific whale falls, vent and seep ecosystems. This similarity strongly supports the hypothesis that whale falls act as \"stepping-stones\" for the dispersion of chemosynthetic fauna and that some whale-fall specialists are widespread worldwide at genus level. Detailed investigation of inner bone assemblages indicates that Osedax degradation deeply affects their diversity and structure. Bones colonized by Osedax support distinct, significantly more diverse and abundant assemblages. This renders Osedax the status of ecosystem engineer, creating new microhabitats and enhancing biodiversity in deep-sea whale-fall communities.<br>O presente estudo descreve a composição faunística e a estrutura da comunidade de carcaça de baleia mais profunda do mundo e a primeira a ser encontrada no Oceano Atlântico Sul. A descoberta adiciona dados importantes à quase desconhecida biogeografia destas comunidades, assim como aumenta o conhecimento sobre o papel ecológico dos vermes-zumbis do gênero Osedax (Polychaeta: Siboglinidae), especialistas no consumo e degradação de ossos. A carcaça foi fortuitamente descoberta em 24 de Abril de 2013, na base da Dorsal de São Paulo a 4204 m de profundidade (Atlântico Sudoeste), utilizando-se o submersível de pesquisa tripulado Shinkai 6500 (Agência Japonesa para o Estudo das Ciências do Mar e da Terra e Tecnologia, JAMSTEC na sigla em inglês). Os mergulhos fizeram parte da Expedição Oceanográfica Iatá-Piúna, fruto de um acordo bilateral de cooperação científica em Ciências do Mar entre Brasil e Japão. Durante dois mergulhos foram feitos vídeos detalhados da carcaça através de uma câmera de alta definição. Também foram coletadas vértebras, sedimentos e fauna por meio dos braços manipuladores e de um sugador. O esqueleto parcial pertencia a uma baleia Minke Antártica, Balaenoptera bonaerensis, e era composto por nove vértebras, cujo estado de degradação sugere que a baleia estava no assoalho marinho por pelo menos 5 anos. A maioria das 41 espécies de invertebrados encontradas são novas para a ciência e cerca de 12% dos gêneros são compartilhados com ambientes redutores do Pacífico Nordeste, como carcaças, fontes hidrotermais e exsudações frias. Tal semelhança corrobora fortemente a hipótese de que carcaças de baleia atuam como \"pedras de dispersão\" para a fauna de ambientes quimiossintetizantes e que alguns organismos especialistas de carcaças de baleia possuem distribuição mundial em nível genérico. A investigação detalhada da endofauna dos ossos indicou que a degradação promovida por Osedax afeta profundamente sua diversidade e estrutura. Ossos colonizados por Osedax sustentam assembleias de organismos significativamente mais diversas e abundantes. Isso faz com que Osedax seja considerado um engenheiro ecossistêmico, pois cria novos microhábitats promovendo o aumento da biodiversidade em comunidades de carcaças de baleia no mar profundo.
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Cordeiro, Joana Sousa. "Preservar a memória." Master's thesis, Universidade de Lisboa, Faculdade de Arquitetura, 2019. http://hdl.handle.net/10400.5/18276.
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Dissertação de Mestrado Integrado em Arquitetura, com a especialização em Interiores e Reabilitação do Edificado apresentada na Faculdade de Arquitetura da Universidade de Lisboa para obtenção do grau de Mestre.<br>reconhecimento da importância para o desenvolvimento das atividades náuticas e o contributo económico que esta indústria proporcionou aos Açores, foram o incentivo para a realização deste trabalho.
Num mundo em que as ruínas e o abandono estão cada vez mais presentes nos edificados das nossas vilas e cidades, é de interesse discutir e refletir sobre o passado e a relevância destes objetos, traçando-lhes um futuro melhor, contribuindo para a nossa identidade.
A União das Armações Baleeiras de São Miguel, vulgarmente apelidada de Fábrica da Baleia de São Vicente Ferreira, hoje já sem presença física, onde só resta a sua imponente chaminé e a memória dos que fizeram da baleação o seu modo de vida, é um marco importante na história dessa Região, em particular na sua atividade industrial.
A sua ruína e demolição, foi fruto da extinção de uma indústria que perdeu expressão, conjugada com a proibição da prática da caça á baleia, colmatada pela incúria de outros.
Em Preservar a Memória, procuramos desenvolver uma narrativa crítica com bases históricas e culturais, dando forma à proposta de um espaço de lazer, cultural com uma componente habitável para os Açorianos, e não só, amantes e curiosos pelas atividades náuticas e da baleação.
O lugar em estudo apresenta três acentuados desníveis. A partir dessas diferenças altimétricas organizou-se o novo programa, utilizando-as para promover cada um dos três setores de atividade propostos, desde do mais público ao mais privado.
O setor histórico e cultural é proporcionado por uma Casa Museu Baleia, corpo onde outrora terá sido a Fábrica da Baleia, dando passagem para um Centro de Investigação e Lazer Náutico, observados do nível altimétrico mais elevado por pequenos alojamentos de apoio às duas estruturas anteriores.<br>ABSTRACT: The recognition of the importance for the development of the nautical activities and the economic contribution that this industry gave to the Azores, were the incentive for the accomplishment of this work.
In a world where the ruins and the abandonment are increasingly present in the edifices of our towns and cities, it is of interest to discuss and reflect on the past and the relevance of these objects, drawing them a better future, contributing to our identity.
The Union of the Balearic Islands of São Miguel, commonly dubbed the Whale Factory of São Vicente Ferreira, now without a physical presence, where only its imposing chimney and the memory of those who have made whaling their way of life remain, is a milestone. important in the history of this Region, particularly in its industrial activity.
It’s ruin and demolition were the result of the extinction of an industry that has lost its expression, coupled with the prohibition of whaling, which is filled by the negligence of others.
In Preserve a Memory, we seek to develop a critical narrative with historical and cultural bases, giving form to the proposal of a cultural and leisure space with a habitable component for the Azoreans, and not only, lovers and curious for nautical activities and whaling.
The study site has three differences. From these altimetric differences the new program was organized, using them to promote each of the three proposed sectors of activity.
The historical and cultural sector is provided by a Whale House Museum, giving way to a Center for Research and Nautical Leisure, observed from the highest altimetric level by small accommodation to support the two previous structures.<br>N/A
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Bouffaut, Léa. "Detection and classification in passive acoustic contexts : application to blue whale low-frequency signals Passive stochastic matched filter for Antarctic blue whale call detection, in The Journal of the Acoustical Society of America 144 (2), 2018 Baleen whale distribution and seasonal occurrence revealed by an ocean bottom seismometer network in the Western Indian Ocean, in Deep Sea Research Part II: Topical Studies in Oceanography 161, March 2019." Thesis, Brest, 2019. http://www.theses.fr/2019BRES0057.
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L’analyse des grands volumes de données générés par la surveillance par acoustique passive long-terme et continue des baleines bleues (BW) est améliorée par la détection automatisée des signaux d’intérêt. Le travail présenté dans cette thèse s’attaque au problème de la détection et classification de signaux stéréotypés dans un contexte passif basse fréquence où les signaux sont modifiés par le canal de propagation, bruités et où le SNR varie continuellement. Les méthodes développées sont appliquées à des enregistrements issus d’OBS déployés dans l'océan Indien occidental.Premièrement, le filtrage adapté stochastique (SMF) est étendu au contexte passif en adaptant l’estimation du bruit et du SNR. Ce filtre est appliqué avec succès pour la détection des calls de baleine bleue antarctique et est comparé aux MF et Z-detector sur données annotées présentant de nombreux bruits et d’importantes variations du SNR. Les excellentes performances du SMF passif permettent d’augmenter la portée de détection jusqu'à 100 km en présence de bruit de bateau.La détection simultanée de différentes espèces s’appuie sur un schéma de reconnaissance de formes où les signaux tonaux de BW sont extraits, caractérisés et classifiés pour la transcription automatique des chants.Les signaux ainsi identifiés sont ensuite reconstruits avec des formes d'onde distinctes reproduisant les chants sous-jacents. Le succès de la reconstruction repose sur la qualité de la détection de tonales: le détecteur de crêtes est choisi pour son efficacité. Les résultats d'apprentissage et la première application non supervisée de la transcription ont révélé des résultats prometteurs et son utilité pour l’analyse multi-espèces<br>The analysis of the large volumes of data resulting from continuous and long-term monitoring efforts of blue whales (BWs) benefits from the automated detection of target signals. This thesis investigates the challenging problem of the detection and classification of stereotyped signals in a low-frequency passive acoustic context where (1) signals traveling long distances are deteriorated by the propagation channel, (2) overlapping noises interfere and, (3) SNRs vary continuously. Developed methods are applied to recordings from ocean bottom seismometers deployed in the western Indian Ocean.First, the stochastic matched filter (SMF) is adapted to the passive context by overcoming noise estimation and estimating the SNR automatically. This filter is successfully applied to the detection of Antarctic blue whales calls and is compared to the MF and the Z-detector on an annotated ground-truth dataset exhibiting various SNRs and noises. The passive SMF showed better performances, increasing the detection range up to 100 km in the presence of ship noise.The problematic of the detection of concurrently calling species is addressed based on a pattern recognition development for the automatic transcription of BW songs where, tonal signals are extracted, characterized, and classified. The hence identified signals are then reconstructed as separate waveforms reconstructing of the underlying songs. The success of the reconstruction relies on the quality of the tonal detector: the ridge detector was chosen for its efficiency. Training and unsupervised application revealed promising results of the proposed transcription method and its utility for multi-species analysis
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Escalle, Lauriane. "Spatio-temporal interactions between whale sharks, cetaceans and tropical tuna purse-seine fisheries, within a conservation perspective, in the Atlantic and Indian Oceans." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT125/document.
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Dans le cadre de l’Approche Ecosystémique des Pêches (AEP), il est nécessaire d’évaluer l’impact de la pêche thonière tropicale à la senne sur les espèces ciblées et sur les espèces accessoires. Parmi ces dernières, les espèces de la mégafaune, telles que des requins, raies, cétacés, tortues, oiseaux marins, sont souvent emblématiques et vulnérables. Les thoniers senneurs tropicaux recherchent activement à la surface de l’eau tout indice de la présence de bancs de thon (e.g. oiseaux, objets flottants, baleines, dauphins ou requins baleines). Dans l’est de l’océan Atlantique et l’ouest de l’océan Indien, les deux modes de pêches principaux sont les captures de thons en bancs libres et celles sur bancs associés à un objet flottant, naturel ou artificiel, rassemblés ici sur sous le terme de dispositif de concentration de poisson (DCP). Les calées associées aux requins baleines et aux cétacés sont toutefois peu étudiées. L’objectif de cette thèse est donc d’analyser les co-occurrences et/ou interactions spatio-temporelles entre requins baleines, cétacés et pêche thonière à la senne, dans une perspective de conservation de l’écosystème. Ce travail, basé sur des données de livres de bord et d’observateurs scientifiques embarqués, a montré que la co-occurrence pêche thonière/ mégafaune se localise dans des strates spatio-temporelles relativement précises: i) du Gabon à l’Angola (avril–septembre), ii) dans le Canal du Mozambique (juin–septembre) et iii) à l’est des Seychelles (avril–septembre). Les baleines et requins baleines étant planctivores, la co-occurrence avec la pêche à la senne est principalement liée à une forte productivité primaire (appréhendée à travers des proxys tels que la concentration en chlorophylle-a). De plus, les calées sur ces deux groupes étaient assez élevées avant 2000 (jusqu’à 20% des calées), et qu’elles sont moins fréquentes aujourd’hui (AC3 et 1,5% des calées associées à des baleines et des requins baleines, respectivement). L’impact de la pêche à la senne sur ces espèces semble relativement faible au regard du taux de mortalité apparente de 1,4% pour les requins baleines et 5,6% pour les cétacés. Des marquages satellites réalisés sur les requins baleines, confirment ces observations sur le plus long terme, mais la taille de l’échantillon limite la formulation de conclusions définitives. Concernant les dauphins, bien que présents sur les zones de pêche, ils interagissent très peu avec celle-ci, soulignant ainsi une différence majeure avec l’océan Pacifique est où ce mode de pêche est majoritaire. La diversité spécifique des espèces cible et accessoire associées aux calées sur mégafaune a également été étudiée. Les requins baleines sont associés aux listaos et à l’albacore (dans une large gamme de tailles), alors que les baleines le sont principalement à de gros albacores. De plus, la capture accessoire associée à ces deux groupes de mégafaune est relativement faible et dominée par le requin soyeux et la diversité spécifique est proche de celle trouvée sous les bancs libres de thons. Enfin les effets de mesures de conservation vis-à-vis de la mégafaune encerclée ou de mesures de gestion de l’effort de pêche, notamment les moratoires sur DCP réelles ou simulées (e.g. moratoires élargis), ont été analysés. Les premières ont eu un effet limité en terme de captures cibles et accessoires, alors que les moratoires impactent peu le nombre de calées associés à la mégafaune, ceci en raison du décalage spatio-temporel des co-occurrences. Cependant des moratoires élargis pourraient être bénéfiques pour les thons juvéniles et certaines espèces associées. Par l’analyse quantitative des interactions entre la pêche thonière à la senne et la mégafaune, cette thèse apporte des connaissances essentielles sur les espèces étudiées dans le cadre de la mise en place d’une AEP, applicable à la pêche thonière tropicale<br>In the frame of the Ecosystem Approach to Fishery (EAF) management, impact of the tropical tuna purse-seine fishery on targeted and incidentally captured species should be investigated. They may include megafauna species, such as sharks, rays, cetaceans, turtles or sea birds, which often are emblematic and vulnerable species. Tropical tuna purse-seiners actively search, at the surface of the sea, for clues indicating the presence of tuna schools (e.g. birds, floating objects, whales, dolphins or whale sharks). In the eastern Atlantic and western Indian Oceans, the main two fishing modes are sets on free swimming tuna schools and schools associated to natural or artificial floating objects, thereafter called Fish Aggregating Device (FAD). However dedicated studies on fishing sets associated to whale sharks and cetaceans are still lacking. The aim of this thesis is therefore, using logbook and scientific onboard observer data, to investigate the spatio-temporal co-occurrences and/or interactions between whale sharks, cetaceans and the tuna purse-seine fishery within an ecosystem conservation perspective. This work underlines that the megafauna/ fishery co-occurrence occurs in specific spatio-temporal strata: i) Gabon to Angola (April–September), ii) the Mozambique Channel (June–September), and iii) East of Seychelles (April–September). As baleen whales and whale sharks are filter feeders, the co-occurrence with the purse-seine fishery was mostly linked to highly productive environments (i.e. using proxys including chlorophyll-a concentration). In addition fishing sets involving megafauna were relatively high before 2000 (up to 20% of the sets), but are nowadays less frequent (AC3 and 1.5% of the sets associated to baleen whales and whale sharks). The purse-seine fishery appears to have a relatively low impact on megafauna species with mortality rates of 1.4% for whale sharks and 5.6% for cetaceans. Whale shark satellite tagging also confirms these results on the longer term, but the low sample size precludes any final conclusion. While dolphins are present in fishing areas, very few interactions with the fishery was detected, which highlights the striking difference with the eastern Pacific Ocean where half the sets are associated to dolphin herds. In addition, the diversity of targeted and bycatch species captured under whale shark and baleen whale sets was also investigated. Whale sharks are principally associated to skipjack and yellowfin (of various sizes) tunas and baleen whales mostly to large yellowfin tuna. In addition, bycatch species associated to these two megafauna groups was relatively low and dominated by the silky shark, and bycatch diversity was close to the one found for free swimming tuna schools. Finally, real and/or simulated encircled megafauna conservation measures or fishing effort management measures (especially FAD moratoria including larger ones) were investigated. The first ones were found to have limited consequences on tuna catch and bycatch. Conversely FAD moratoria had limited impacts on the number of megafauna associated fishing sets, due to the fact that the main spatio-temporal strata of megafauna and FAD sets differ. However larger and longer moratoria could be beneficial for juvenile tuna and some bycatch species. Overall, this thesis has lead to increase the knowledge on megafauna/ fishery interactions, essential in the general framework of setting up an EAF in the tropical tune purse-seine fishery
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Santos, Marcos Roberto Rossi. "Comportamento e ecologia ac?stica da baleia jubarte (Megaptera novaeangliae) na regi?o Nordeste do Brasil." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17228.
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Previous issue date: 2012-08-07<br>Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico<br>The acoustic ecology concept involve the relation between the live organisms and their sound environment and is applied in the present work to study the context in which the humpback whale (Megaptera novaeangliae) singing behavior, known as the most complex display in the nature, occurred in the northeastern Brazilian coast, outside the core area of Abrolhos Bank, between 2005 and 2010.I analyze the singer male occurrence , their spatial distribution and probable relations with oceanographic features, such as depth, tide regimen and moon phases. I also describe the acoustic structure and temporal variation of the singing behavior, based on song frequency and time measurements outside the Abrolhos Bank, and further compare the song complexity, registered in the same period, between Abrolhos Bank (16?- 19? S, 37?- 39? W) and the adjacent North Coast, herein considered from Itacar? (14? S, 38? W) to Aracaju (11? S, 37? W). Additionally, I look for describe and analyze anthropogenic noise sources in the marine environment of the study area, produced by the oil industry as well as by the whale watching operation, relating their frequencies to the acoustic niche utilized by the humpbacks. The results indicated a great plasticity in the singing behavior, evidenced by the occurrence of singer males in diverse social structures, from solitary individuals to other groups, even containing females and calves, as well as by the diversity which compound the song, when compared between two regions inside the same breeding area, which present distinct oceanographic characteristics. The singer male distribution may be related with the continental shelf extent along the study area. The anthropogenic noise presented frequency range, amplitude and sound intensity in potential to interfere acoustically in the singing behavior of the species, may resulting in disturbance during the breeding season in the Brazilian coast. Implications about the obtained results in the humpback whale mating system are discussed. In this way, I pretend to contribute with the acoustic ecology subject and provide information to subsidize humpback whale conservation<br>O conceito de ecologia ac?stica envolve a rela??o entre os organismos vivos e o seu ambiente sonoro e ? aplicado no presente trabalho para estudar o contexto no qual ocorreu o comportamento de canto da baleia jubarte (Megaptera novaeangliae), considerado o mais complexo comportamento reprodutivo (display) da natureza, na costa nordeste do Brasil, fora da concentra??o reprodutiva do Banco de Abrolhos, entre os anos de 2005 e 2010. Analiso a ocorr?ncia de machos cantores em diferentes estruturas de grupo, sua distribui??o espacial e prov?veis rela??es com fatores oceanogr?ficos, como profundidade, regime de mar?s e fases da lua. Tamb?m descrevo a estrutura ac?stica e a varia??o temporal do comportamento de canto, baseado em medi??es de frequ?ncia e tempo dos cantos, fora do Banco de Abrolhos, al?m de comparar a complexidade do canto, registrada no mesmo per?odo de estudo, entre o Banco de Abrolhos (16?- 19? S, 37?- 39? W), e a Costa Norte adjacente, aqui considerada desde Itacar? (14? S, 38? W) a Aracaj? (11? S, 37? W). Ainda busco descrever e analisar as fontes de ru?dos antropog?nicos no ambiente marinho da ?rea de estudo, produzidos pela atividade de explora??o de petroleo e g?s e tamb?m pelo turismo de observa??o de baleias, relacionando-os com o nicho ac?stico utilizado pela jubarte. Os resultados indicaram uma grande plasticidade no comportamento de canto, evidenciado pela ocorr?ncia dos cantores em diversas estruturas sociais, de indiv?duos solit?rios a grupos contendo outros animais, inclusive f?meas com filhotes, bem como pela diversidade que comp?e o canto da esp?cie, quando comparado entre duas regi?es dentro da mesma ?rea de reprodu??o, como o Banco de Abrolhos e a Costa Norte, que apresenta caracter?sticas oceanogr?ficas distintas. A distribui??o dos machos cantores parece estar relacionada com a extens?o da plataforma continental na ?rea de estudo. Os ru?dos antropog?nicos produzidos demonstraram uma faixa de frequ?ncias, amplitude sonora e intensidade capazes de interferir acusticamente no comportamento de canto da esp?cie, podendo resultar em dist?rbios durante o per?odo de reprodu??o da esp?cie na costa brasileira. Implica??es sobre os resultados obtidos na teoria do sistema de acasamento da esp?cie s?o discutidas. Dessa forma, pretendo contribuir com o tema da ecologia acustica e gerar informa??es que subsidiem a conserva??o da baleia jubarte
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Bernardino, Angelo Fraga. "Sucessão ecológica em parcelas orgânicas de madeira, macroalgas e em carcassas de baleia no mar profundo; e similaridade de espécies entre habitats redutores no talude continental da Califórnia (Pacífico Nordeste)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/21/21131/tde-20012010-112207/.
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Parcelas orgânicas de macroalgas, madeira e carcaças de baleia criam importantes oasis de enriquecimento orgânico no assoalho marinho de regiões profundas, mas a estrutura e sucessão ecológica da macrofauna sedimentar ao redor destes ambientes ainda é pouco conhecida. Parcelas de macroalgas e madeira foram artificialmente implantadas próximas a uma carcaça de baleia de 30-ton hà uma profundidade de 1670 m na Bacia de Santa Cruz, Pacífico NE. Ao redor de cada ilha orgânica, foram estudados os padrões espaciais e temporais de enriquecimento sedimentar orgânico e a estrutura e sucessão temporal da macrofauna em escalas temporais que variam de 0.25 à 7 anos. Ainda, o nível de sobreposição entre espécies colonizadoras das parcelas orgânicas e na baleia, foram comparados com comunidades de exudações frias (uma localizada na bacia de São Clemente, Pacífico NE) e fontes hidrotermais. Em geral, a abundância da macrofauna sedimentar foi altamente elevada em períodos de intenso enriquecimento orgânico, com decréscimo da diversidade da macrofauna num raio de 0.5 metros das parcelas. Nas parcelas de macroalgas e madeira, espécies oportunistas e tolerantes à sulfetos atingiram altas densidades após o pico de enriquecimento orgânico sedimentar (0.25 e 1.8 anos, respectivamente), enquanto que ao redor da carcaça de baleia, a macrofauna foi também dominada por organismos quimiossintéticos com associações simbióticas bacterianas, e ainda espécies oportunistas que se alimentavam do abundante carpete bacteriano sobre a superfície sedimentar. Os sedimentos ao redor das parcelas de macroalgas e madeira sustentam baixas taxas de degradação microbiana e sulfeto intersticial, recrutando assim um limitado número de organismos quimioautotróficos e consequentemente com baixa sobreposição de espécies com outros ambientes redutores. Na carcaça de baleia, os sedimentos sustentam intensa degradação microbiana e altos níveis de sulfeto, mas diferenças marcantes nas biogeoquímica e nas cadeias tróficas presentes nestas carcaças resultam em baixa sobreposição de espécies com a fauna de exsudações frias e fontes hidrotermais. Conclui-se que sedimentos enriquecidos organicamente ao redor de macroalgas, madeiras e carcaças de baleia criam importantes hábitats para a persistência e evolução de espécies dependentes de condições sedimentares redutoras, e assim estas ilhas devem contribuir para a diversidade regional e global dos ecossistemas de mar profundo.<br>Sunken parcels of macroalgae, wood and whale carcasses provide important oases of organic enrichment at the deep-sea floor, but sediment community structure and succession around these habitat islands are poorly evaluated. We experimentally implanted parcels of kelp and wood falls nearby a 30-ton deep-sea whale-fall at 1670 m in the Santa Cruz Basin (SCr; NE Pacific). At each organic island, we aimed to evaluate patterns of organic enrichment and spatial and temporal patterns of macrofaunal community structure and succession over time scales of 0.25 to 7y. Additionally, species overlap between kelp-, wood- and whale-falls with nearby cold-seep communities were investigated. In general, the abundance of infaunal macrobenthos was highly elevated at periods of intense organic enrichment at all organic falls, with decreased macrofaunal diversity and evenness within 0.5 meters of the falls. At kelp and wood falls opportunistic species and sulfide tolerant microbial grazers (dorvilleid polychaetes) abounded after the peak of sedimentary enrichment (0.25y and 1.8y, respectively), while the whale-fall macrofauna was highly abundant from 4.5 to 6.8 y, and was dominated by enrichment opportunist, chemoautotrophic-symbiont-hosting and heterotrophic species grazing sulfur-oxidizing bacterial mats. Sediments around kelp and wood parcels provided lowintensity reducing conditions, which sustain a limited chemoautotrophically-based fauna, with low levels of species overlap among other chemosynthetic habitats in the deep NE Pacific. Whale-fall sediments harbor many species and trophic types not present in background sediments, but there were low levels of species overlap between the whalefall, cold seeps and hydrothermal vents, explained by differences in biogeochemistry and food webs among these habitats. We conclude that organically enriched sediments around kelp, wood and whale-falls may provide important habitat islands for the persistence and evolution of species dependent on organic- and sulfide-rich conditions at the deep-sea floor and contribute to regional and global diversity in deep-sea ecosystems.
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ROCHA, Bruno César Luz Macena. "Estudo da sazonalidade, distribuição, abundância e comportamento migratório do tubarão-baleia (Rhincodon typus Smith, 1828) no Arquipélago de São Pedro e São Paulo." Universidade Federal Rural de Pernambuco, 2010. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6245.
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Previous issue date: 2010-06-17<br>Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq<br>Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq<br>In Saint Peter and Saint Paul archipelago (SPSPA), located at mid-Atlantic ridge, near to Equator line, population aspects of whale sharks was analized through in situ observation on distribution, seasonality, different behavior, and photo-identification. The movements of whale sharks was tracked using two models of satellite tag: SAT (Satellite Argos-linked transmitter) and PSAT (Pop up satellite archival transmitting tag) in one male (TB-01; 4.8 m) and one female (TB-02; 8.5 m),respectively. Whale shark occur in SPSP adjacencies yearround,although, are more abundant in the first semester, mainly, in February, March, and June. The annual record mean was 10.8 year-1 between 2000 and 2009. The size ranges from 1.8 to 14.0 m with mean± s.d. equal to 7.4± 2.4 m and the majority (62.9%) of whale sharks smaller than 9.0 m, under the estimated size at first maturation. Data received from Argos Satellite system indicate that the whale shark swam away from archipelago heading west. Both sharks spent the major of the time at surface, and the TB-02 dove into bathypelagic zone, attaining the maximum depth of 1,976 m. This was the first initiative to understand behavioral and population dynamics aspects of the whale sharks as well as the movement in Brazil and Equatorial Atlantic from SPSPA and will continue in the hope of building better conservation strategies.<br>No Arquipélago de São Pedro e São Paulo (ASPSP), localizado na dorsal meso-Atlântica, próximo à linha do Equador, foram analisados aspectos da população do tubarão baleia por meio de observação in situ. Informações sobre a distribuição e sazonalidade de ocorrência, diferentes comportamentos foram coletados e, quando possível, os espécimes foram fotografados para posterior individualização. Para elucidação do deslocamento do tubarão-baleia, a partir do ASPSP, foram utilizados dois modelos de transmissores via satélite, o SAT (Satellite Argos-linked tag) e o PSAT (Pop up satellite archival transmitting tag) em um macho (TB-01) e uma fêmea (TB-02) de 4,8 e 8,5 m, respectivamente. Os tubarões-baleia visitam o arquipélago durante o ano inteiro, entretanto, o primeiro semestre possui uma frequência mais elevada, principalmente nos meses de fevereiro, março e junho. A média anual de registros foi 10,8 ano-1 entre 2000 e 2009. Os comprimentos variaram entre 1,8 e 14,0 m com média± d.p. igual a 7,4± 2,4 m, com a maior parte (62,9%) dos tubarõesbaleia com comprimento abaixo do tamanho estimado para primeira maturação. Os dados dos transmissores recebidos pelo Sistema Argos de satélites indicaram que os tubarões se afastaram do ASPSP, logo após a marcação, em direção oeste. Ambos os tubarões permaneceram a maior parte do tempo na superfície e o TB-02 realizou mergulhos batipelágicos alcançando a profundidade máxima de 1.976 m. Esta foi a primeira iniciativa para se compreender aspectos populacionais e comportamentais, bem como da movimentação de tubarões-baleia no Brasil e no Atlântico Equatorial a partir do ASPSP e terá continuidade na expectativa de construir de estratégias espaciais de conservação.
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Abras, Daniela Rodrigues. "Efeito de parâmetros ambientais na migração de baleias-jubarte (Megaptera novaeangliae) entre Mar de Scotia e Banco dos Abrolhos." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-08062015-165443/.
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Fatores exógenos, como fotoperíodo, temperatura da superfície do mar e abundância de presas, e endógenos, como os ciclos circadianos e circanuais e alterações metabólicas são conhecidos como iniciadores dos movimentos migratórios. Este trabalho tem como objetivo estabelecer os principais parâmetros iniciadores da migração das baleias-jubarte. Foram analisados o fotoperíodo, índice de oscilação do oceano austral (SOI), temperatura da superfície do mar, concentração de clorofila-a e densidade de krill em relação ao número máximo de indivíduos avistados e o dia do pico de avistagem. O fotoperíodo mostrou ser o principal fator que influencia a migração da Antártica em direção a Abrolhos, enquanto que o caminho contrário, além de fotoperíodo, parece ser influenciado também pelo os fatores tais como temperatura da superfície do mar e a quantidade de presas disponíveis no verão anterior. Quanto maior a densidade de krill, maior o número máximo de indivíduos avistados e a temporada reprodutiva mais longa. O SOI mostrou ter influência no ciclo reprodutivo do krill. Valores negativos registraram maior densidade de krill e valores positivos, menor densidade de krill, através do modelo GLM. Altos valores de TSM apresentaram correlação negativa com a densidade de krill, e com o número de baleias avistadas e o tempo de permanência na área reprodutiva, indicando que o aquecimento da região antártica impõe condições não favoráveis para a temporada reprodutiva das baleias.<br>Exogenous factors, such as photoperiod, sea surface temperature and abundance of prey, and endogenous, such circadian and circannual cycles and metabolic changes are known as initiators of migratory movements. This work aims to establish the main parameters initiators of the migration of the humpback whales. The photoperiod, the Southern Ocean Index (SOI), the sea surface temperature, the chlorophyll-a concentration and the density of krill were analyzed in relation to the maximum number of individuals sighted and the duration of the reproductive season. The photoperiod showed to be the main factor that influences the migration from Antarctica to Abrolhos, while the opposite way, besides photoperiod, seemed to be influenced also by other factors such as sea surface temperature and the amount of prey available in the previous summer. The higher the density of krill, the greater the maximum number of individuals sighted and the longer the reproductive season. The SOI showed to have influence on the reproductive cycle of krill. Negative values correspond to higher density of krill, and positive values, lower density of krill, through the GLM model. High values of TSM presented negative correlation with the density of krill, and with the number of whales sighted and the reproductive season duration in the reproductive area, indicating that the Antartic warming impose unfavorable conditions for the reproductive season of whales.
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Trudelle, Laurène. "Distribution et préférences d'habitats des baleines à bosse de l'hémisphère Sud en période de reproduction." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS038/document.
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L’étude des déplacements des baleines à bosse (Megaptera novaeangliae) en relation avec les paramètres environnementaux permet d’apporter des informations précieuses sur leur distribution et leurs préférences d’habitats. Grâce à des données d’observations opportunistes collectées dans le canal de Sainte Marie (Nord-Est de Madagascar) et des données de télémétrie collectées pour cette étude (25 baleines équipées de balises Argos), cette thèse a pour objectif l’étude des déplacements et de l’utilisation de l’habitat des baleines à bosse de Madagascar en fonction du sexe et du statut reproducteur. Des variables physiographiques et océanographiques (mesurées par satelllite) ont été extraites sous chaque position. Un schéma général d’utilisation de l’habitat en période de reproduction a également été proposé à partir de données de télémétrie provenant de différentes zones de reproduction de l’Hémisphère Sud: le Brésil (n=82 individus), l’Australie de l’Ouest (n=26) et l’Australie de l’Est (n=11). Dans le canal de Sainte Marie, nos résultats ont montré une ségrégation temporelle d’un mois avec une première partie de saison dominée par les groupes avec baleineaux et une seconde dominée par les groupes sans baleineaux (Chapitre III). La profondeur influence la distribution des groupes sociaux avec une préférence des couples mère-baleineau pour les plus faibles profondeurs (< 20 m). Le long de la côte de Madagascar, les déplacements localisés des femelles sont associés à des habitats plus profonds et plus éloignés de la côte que ce qui avait été supposé (Chapitre IV). En revanche, les mâles ne semblent pas montrer de préférences d’habitats particuliers bien qu’ils diminuent leur vitesse de nage dans les zones peu profondes. En zone océanique, les individus se déplacent de façon plus erratique dans les eaux les moins profondes, de faible courant ou les plus riches en chlorophylle a. La vitesse du courant de surface ne semble pas être un facteur majeur dans le déplacement des baleines à bosse. Cependant, elles semblent suivre la même direction que celui-ci lorsque ce dernier est fort. Notre étude comparative entres les zones de reproduction a montré que la distribution spatiale varie selon la période de la saison, entre les sites étudiés et selon le sexe (Chapitre V). En début et fin de saison, les mâles se déplacent de manière plus directe et exploitent des zones plus au large que les femelles, notamment celles avec baleineau. Au pic de la saison, les mâles et les femelles effectuent des déplacements plus localisés. La prise en compte des différences dans la variabilité spatio-temporelle des mâles et des femelles en zone de reproduction apparait être une nécessité pour mieux comprendre l’écologie des baleines à bosse et contribuer à la conservation de l’espèce<br>Of key importance for the comprehension of humpback whales’ (Megaptera novaeangliae) distribution patterns and habitat use is to quantify how ecological and environmental factors affect the distribution of animals, which requires knowledge on dispersal movements of individuals. Using an opportunistic sightings dataset collected in the Sainte Marie Channel (Northeast of Madagascar) and satellite telemetry data acquired for this study (25 tagged whales), the aim of this thesis was to study the movements and the habitat use of humpback whales in Madagascar during the breeding season, according to sex and reproductive status. Physiographic and oceanographic variables (measured by satellite) were extracted under each position. A general distribution pattern of habitat use during the breeding season was also proposed based on additional humpback whales tracks from others breeding grounds of the Southern Hemisphere: Brazil (n=82 individuals), the Western Australian coast (n=26), and the Eastern Australian coast (n=11). In the Sainte-Marie Channel, groups without calves dominated the first 30 days of the breeding season, followed by an increase in groups with calves (Chapter III). Water depth influenced the distribution of social groups with mother-calf pairs more frequently found in relatively shallow water (0-20 m). Along the coast of Madagascar, over the shelf, females showed localized behavior in deep water and at large distances from shore suggesting that their breeding habitat extends beyond the shallow coastal waters (Chapter IV). Males’ active swimming speed decreased in shallow waters, but we found no influence of environmental parameters on males’ movements. In oceanic habitats, both males and females showed localized behaviors in shallow waters and high surface chlorophyll-a concentrations. The active swimming speed accounts for a large proportion of the whale observed speed while observed direction of tagged whales tending to be closer to the current direction when the current intensity was high. Our comparative study between breeding areas showed that the spatial distribution varies according to the period of the season, between the studied sites, sex and breeding status (Chapter V). Early and late in the season, males moved more directly and in more offshore areas than females, especially females with calves. At the peak of the season, both males and females performed more localized movements than at the other periods. Accounting for differences in the spatio-temporal variability of the distribution of males and females in the breeding grounds seems a necessity to better understand the humpback whales ecology and contribute to the species conservation
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Godoy, Maria Luiza Motta Pacheco de. "Estudo das taxas reprodutivas e capturabilidade de baleias jubarte Megaptera novaeangliae (BOROWSKI, 1781; CETACEA: MYSTICETI), em sua principal área de concentração para reprodução na costa brasileira (Banco dos Abrolhos, Bahia, Brasil)." Universidade Federal de Juiz de Fora (UFJF), 2007. https://repositorio.ufjf.br/jspui/handle/ufjf/3944.
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Previous issue date: 2007-03-27<br>CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>A caça comercial desenvolvida no início do século XX dizimou populações de baleias jubarte (Megaptera novaeangliae) em muitas regiões do oceano Antártico, entre elas os arredores da ilha Geórgia do Sul. Recentemente, este local foi confirmado como destino migratório das jubartes que se concentram no banco dos Abrolhos, situado entre a Bahia e Espírito Santo, durante a estação de reprodução. Embora em fase de crescimento populacional, este estoque pode apresentar sobrecargas ecológicas tais como alterações na taxa de nascimentos em conseqüência da intensa exploração a que foram submetidos. Este estudo objetivou o levantamento de informações a respeito das taxas brutas de nascimento e de fertilidade de baleias jubarte entre os anos de 1992 e 2003. Como parte desse trabalho, informações sobre comportamento e composição social de animais foto-identificados entre 1989 e 2003, foram relacionadas à probabilidade de captura dos indivíduos. Seus efeitos nas análises de Marcação e Recaptura também foram considerados. O teste G revelou diferenças significativas entre as taxas brutas de nascimento ao longo dos anos, tanto para os registros de foto-identificação (Média = 0,054 ± 0,012; p<0,001) quanto para as informações provenientes de observações a bordo de cruzeiros de pesquisa (Média = 0,192 ± 0,05; p<0,001). Já as taxas de fertilidade se mostraram semelhantes ao longo de todo o período de estudo (Média = 0,87± 0,12; p>0,05). Este trabalho identificou diferenças significativas na probabilidade de captura por fotografia dos indivíduos de acordo com o status reprodutivo (H= 25,01; p = 0,003). A capturabilidade também diferiu em relação ao número de componentes de um grupo, onde associações de até três indivíduos apresentaram probabilidade de captura significativamente maior em relação aos grupos compostos por mais de quatro indivíduos (U = 16; p<0,05). Os resultados aqui identificados revelaram que a maior probabilidade de captura no banco dos Abrolhos se dá em grupos constituídos por três adultos, o que difere de outras áreas de reprodução como Silver Bank, no oceano Atlântico norte, onde os solitários apresentaram maior capturabilidade.<br>The commercial whaling developed during the XX century dizimated many humpback whale (Megaptera novaeangliae) populations of Southern Hemisphere. One of them, found around South Georgia Island, is known to migrate to the Brazilian coast during the breeding season. The intense past exploration have resulted in ecological trends such as changes in reproductive rates. Photo-identification and ship surveys conducted at Abrolhos Bank from 1989 to 2003 were analyzed with the main goal to evaluate how these values are changing over the years. The crude birth rate differed significantly by year (Cruise surveys: Mean = 0,192 ± 0,05; G Test, p<0,001/ Photo-identification: Mean = 0,054 ± 0,012; G Test, p<0,001). Nevertheless, the calving rate showed no significant differences by year (Mean = 0,87± 0,12; G Test; p>0,05). This study verified significant differences in catchability related to the reproductive status (H = 25,01; p = 0,003) and number of individuals composing a group. Associations with three or less individuals showed higher catchability compared to groups composed by four and more animals (U = 16; p<0,05). The highest probability of a whale from Abrolhos Bank be photo-identified was in a group composed by three adults.
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Derville, Solène. "Écologie spatiale des baleines à bosse en zone de reproduction : habitats, distribution et mouvements dans le Pacifique Sud." Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS374.
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Comprendre les facteurs sociaux et environnementaux de la distribution et des mouvements de la mégafaune marine est essentiel à sa conservation. Les cétacés sont des espèces rares et mobiles, dont la gestion nécessite une meilleure compréhension des habitats qu’ils occupent. Cette thèse a eu pour but d’étudier l’écologie spatiale d’une population en danger de baleines à bosse (Megaptera novaeangliae) dans l’océan Pacifique Sud. En utilisant un ensemble de données multidisciplinaires collecté entre 1995 et 2018 en Nouvelle-Calédonie et en Océanie, cette thèse a poursuivi trois objectifs : 1) étudier les meilleures pratiques de modélisation de la distribution des cétacés, 2) acquérir une meilleure compréhension de la distribution, des habitats et des mouvements des baleines à bosse dans leur zone de reproduction d’Océanie, 3) prédire les zones de conservation prioritaires et les menaces potentielles pour les baleines à bosse dans cette région. La modélisation de la distribution d’une grande baleine migratrice à partir de données de recherche non systématique et issues de la science participative a fourni des prédictions de bonne qualité, tant que l’hétérogénéité spatiale de l’échantillonnage et la tendance statistique au surapprentissage étaient correctement prises en compte. Les modèles additifs généralisés ont été privilégiés pour leur équilibre en termes de complexité des relations modélisées, leur rendu écologiquement explicite et leur capacité de transferabilité. Les modèles d’utilisation de l’habitat à différentes échelles spatiales ont révélé une préférence pour une diversité d’habitats peu profonds répartis dans une large gamme de température des eaux en Océanie. Les monts sous-marins et bancs peu profonds ont été identifiés comme d’importants habitats de reproduction et de développement pour les baleineaux. Ces reliefs sous-marins jouent également un rôle clé dans la connectivité au sein et entre les populations. Cette utilisation unique et inattendue de l’habitat pélagique a des conséquences importantes sur la gestion spatiale des baleines à bosse. La prédiction des habitats de reproduction présents et futurs à des échelles multiples fournit une base scientifique pour la désignation de zones de conservation prioritaires et la protection contre les menaces générées par les activités humaines et le changement climatique dans le Pacifique Sud<br>Understanding the social and environmental drivers of the distribution and movements of marine megafauna is essential to their conservation. Cetaceans are elusive and mobile species, whose management requires an improved understanding of habitat use patterns. This thesis is aimed at investigating the spatial ecology of an endangered population of humpback whales (Megaptera novaeangliae) in the South Pacific Ocean. Using a multidisciplinary dataset collected between 1995 and 2018 in New Caledonia and Oceania, this thesis addressed three objectives, 1) investigate best practices to cetacean species distribution modeling, 2) acquire fundamental knowledge on the distribution, habitats and movements of humpback whales in Oceania breeding grounds, and 3) predict priority conservation areas and potential threats to humpback whales. Modeling the distribution of a migratory large whale from non-systematic visual survey and citizen science data provided valuable space-use predictions when uneven survey effort and statistical overfitting were specifically addressed. Generalized Additive Models were favored for their complexity trade-off, ecological interpretability and transferability. Models of habitat use revealed a preference for a diversity of shallow habitats (low island and atoll lagoons, barrier reef and high island slopes, banks and seamounts) spread over a relatively large thermal range over Oceania. Shallow seamounts and banks were identified as major breeding and nursing habitats and play a key role in the connectivity within and between populations. This unique and unexpected use of pelagic waters has important consequences for the spatial management of humpback whales. The predictions of present and future suitable humpback whale breeding habitats at multiples scales provide science-based evidence for priority conservation areas, and enable mitigation of threats from anthropogenic activities and climate change in the South Pacific
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Morete, Maria Emilia. "Caracterização temporal da estrutura de grupos e do comportamento de baleias jubarte (Megaptera novaeangliae) na área de reprodução da região do Arquipélago dos Abrolhos (Bahia, Brasil)." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-14082007-160824/.
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Baleias jubarte usam a costa leste do Brasil como área de reprodução e cria. As águas ao redor do Arquipélago dos Abrolhos são importantes devido a grande concentração de grupos com filhotes. Um estudo de 7 anos (entre 1998 e 2004) foi realizado, a partir de um ponto fixo de observação em terra, a fim de se investigar padrões temporais na estruturação de grupos e no comportamento de baleias jubarte. Dependendo das condições climáticas e de visibilidades eram realizadas varreduras com duração de 1 hora e na seqüência, observações de grupo ou indivíduo focal. Concomitante com o aumento da população brasileira de baleia jubarte, o número de avistagens de baleias adultas ao redor do Arquipélago aumentou, especialmente de 2002 a 2004, porém avistagens de filhotes somente aumentaram durante a temporada 2004. De uma forma gradual baleias chegam, se concentram e partem de Abrolhos, refletindo a migração segregada e as alterações de status sociais dos indivíduos. A medida que a temporada progride, ocorre uma mudança na freqüência das diferentes categorias de grupo de baleia jubarte, de grupos sem filhotes para grupos com filhotes, assim como os comportamentos, os quais, dentro de cada categoria de grupo, parecem estar adequado ao estágio de desenvolvimento do filhote (para aqueles grupos com filhote) e refletem o que parece estar relacionado a busca por oportunidades de acasalamentos e interações sociais. Ao longo das 7 temporadas estudadas, não houve mudanças na estruturação de grupos de baleias jubarte, nem houve alterações comportamentais marcantes. Porém, verificou-se que na presença de barcos num raio de 100-300 metros, fêmeas (mães) permanecem menos tempo em repouso e filhotes ficam menos tempo em comportamento de provável amamentação. Existe a preocupação de que repetidas mudanças comportamentais decorrentes de fatores antrópicos possam levar a população a risco, já que em espécies como baleias, as alterações a nível populacional podem levar muitos anos para ser detectadas. Logo é sugerido que estudos seguindo a mesma metodologia sejam continuados para que comparações sejam possíveis. Um estudo de longo-prazo permitiria uma investigação continua dos padrões (ou alterações deles) com que as baleias jubarte utilizam a área e como vêm respondendo as pressões antrópicas.<br>Humpback whales use the east coast of Brazil as a breeding and calving area. The waters surrounding Abrolhos Archipelago are important because of the high concentration of humpback whale groups with calves. A seven-year study (1998 - 2004) was conducted, from a land base station, to investigate temporal patterns of group structure and behavior of humpback whales. Depending on weather and sightability conditions, one-hour-scans were done followed by observations of animal or group focal follows. Concomitant with the observation of an increasing Brazilian humpback whale population, the number of adult whales sighted around the Archipelago increased, especially from 2002 to 2004. However, sightings of calves only increased during 2004 season. The humpback whales gradually arrive, concentrate and leave the region, reflecting segregated migration and individual social changes. As the season progresses, the frequency of different groups categories changes, from groups without calf to groups with calf, as well as the behaviors, which, within each group category, seems to be appropriate to calf development stages (for groups with calf) and reflect what seems to be related to the search for mating opportunities and other social interactions. During those 7 seasons, there were no changes in humpback whale group structure, nor were there strong behavioral changes. However, it was observed that, in the presence of vessels around 100 to 300 meters, mothers spent less time resting and calves spent less time in activities probably related to suckling. There is a concern that behavioral changes caused by anthropogenic factors may put the population at risk and changes at population level may take several years to be detected. So, it is suggested that studies following the same methodology continues, allowing further future comparisons. A long-term study would permit continued investigation of humpback whale use patterns (or theirs alterations) showing their responses to anthropogenic pressures.
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Souza, Bruno Henrique de Moraes e. "Gastropod fauna on organic falls at the Southwest Atlantic deep-sea." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-05022019-165543/.
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The present study characterized the deep-sea gastropods community collected on whale bones and wood parcels artificially implanted in the deep Southwest Atlantic Ocean at 1500 and 3300 m depth for 23 months. A total of 5493 gastropods were collected and their distribution, abundance and diversity on substrates, depths and latitudes were calculated. Species richness and abundance of gastropods were higher in whale bones and deeper sites. Latitude did not seem to influence the distribution of mollusks. Five species were selected due to their abundance and possible ecological importance for further studies. Three were new species of the superfamily Abyssochrisoidea and were morphologically and genetically described (two Rubyspira and one Cordesia). The other two were Hyslogyrina rissoela (Heterobranchia) and Lusitanops cingulatus (Neogastropoda). To understand their feeding behavior and dispersal strategies were conduced stable isotopes analyzes, observations of gut content, and radular and larval shell morphology. Larval shell of most species suggested planktotrophic development. Animals on different growth stages were found. Gastropods presented a diversity of feeding strategies, such as bacterial mats grazing, predation and specialized bone eating. The overlap of this fauna with other chemosynthetic environments and with other basins corroborate with the ecological stepping stone hypothesis. Besides that, phylogenetic studies about Abyssochrysoidea were made. Their phylogenetic position within the Caenogastropoda are still uncertain but this group is considered closely related with Littorinidae. These snails are endemic from chemosynthetic environments, such as deep-sea hydrothermal vents, cold seeps and organic falls in the deep-sea. The genus Rubyspira is not settled at family level and no molecular studies were made for Cordesia. The present study also attempts to assign these groups phylogenetically. Concatenated COI, 16S, 18S and 28S and individual gene trees were constructed for maximum likelihood and Bayesian analysis. In all analyses the family Newtoniellidae were a sister group of Abyssochrysoidea. Morphological and genetic evidences suggest that Rubyspira and Cordesia are closer related to Abyssochrysos than to other provannid snails. The most accepted hypothesis is that Provannidae is paraphyletic. However, there are other ideas that indicates Rubyspira and Cordesia could be included in Abyssochrysidae or the Provannidae should be considered Abyssochrysidae. A morphologic revision of the superfamily should be made to better understand the relation within the group. Clades within the Abyssochrysoidea were always well supported and similar to those found in the literature. The position of Rubyspira and Cordesia within Abyssochrysoidea suggest whale bones and wood parcels did not play an evolutionary role as stepping stones for this group.<br>O presente estudo caracterizou a comunidade de gastrópodes de mar profundo coletados em carcaças de baleia e parcelas de madeira artificialmente implantadas no Sudoeste do Oceano Atlântico profundo a 1500 e 3300 m de profundidade por 23 meses. Um total de 5493 gastrópodes foram coletados e sua distribuição, abundância e biodiversidade nos substratos, profundidades e latitudes foram calculados. A riqueza e abundância dos gastrópodes foi maior nos ossos de baleia e em maiores profundidades. A latitude parece não ter influenciado na distribuição dos moluscos. Cinco espécies foram selecionadas devido à abundância e possível importância ecológica. Três são novas espécies da superfamília Abyssochrysoidea que foram descritas morfologicamente e filogeneticamente (duas Rubyspira e uma Cordesia). As outras duas foram Hyalogirina rissoela (Heterobranchia) e Lusitanops cingulatus (Neogastropoda). Para compreender os hábitos alimentares e de dispersão desses animais análises de isótopos estáveis, observações do conteúdo do trato digestório, da morfologia das rádulas e das conchas larvais foram realizadas. A concha larval da maioria das espécies sugere um desenvolvimento planctotrófico. Os moluscos encontrados apresentaram diversos tipos de hábitos alimentares como raspadores de carpete bacteriano, predadores e especialistas de ossos. A sobreposição dessa fauna com a de outros ambientes quimiossintéticos e de outras bacias oceânicas colabora com a hipótese ecológica das \"stepping stones\" no mar profundo. Além disso, estudos sobre a posição filogenética dos Abyssochrysoidea foi feita. Sua posição nos Caenogastropoda ainda é incerta, mas são considerados próximos aos Littorinidae. Esses animais são endêmicos de ambientes quimiossintéticos, como fontes hidrotermais de mar profundo, fontes frias e quedas orgânicas. O gênero Rubyspira não está atribuído à nenhuma Família e não foram realizados estudos moleculares para Cordesia. Esse estudo também tenta organizar esses grupos filogeneticamente. Árvores concatenadas e individuais dos genes COI, 16S, 18S e 28S foram construídas para máxima verossimilhança e análise bayesiana. Em todos resultados a família Newtoniellidae foi um grupo irmão dos Abyssochrysoidea. Evidências morfológicas e genéticas s para que sugerem que Rubyspira e Cordesia então mais próximos dos Abyssochrysos do que de outros provannides. A teoria mais aceita é de que os Provannidae são parafileticos. Porém há outras ideias de que Rubyspira e Cordesia poderiam ser inclusos em Abyssochrysidae, ou que os Provannidae fossem considerados Abyssochrysidae. Uma revisão dessa superfamilia deveria se feita para entender as relações desse grupo. Os clados de Abyssochrysoidea sempre foram bem suportados como na literatura. A posição de Rubyspira e Cordesia nos Abyssochrysoidea. aponta que os ossos de baleia e parcelas de madeira possam não terem servido como \"stepping stones\" evolutivas para esses gastrópodes.
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Leroy, Emmanuelle. "Surveillance acoustique des baleines bleues Antarctique dans l’océan Indien austral : traitement, analyse et interprétation." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0069/document.
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La baleine bleue Antarctique, Balaenoptera musculus intermedia, est en danger critique d’extinction depuis la chasse baleinière intensive du 20e siècle. L’état de ses populations et leur écologie restent encore mal connus. En raison de l’inefficacité des observations visuelles, la surveillance par acoustique passive est privilégiée pour étudier cette espèce vocalement très active. Cette thèse porte sur l’analyse de 7 ans de surveillance acoustique passive dans l’océan Indien austral, région d’habitat et de migration particulièrement importante pour la baleine bleue Antarctique. Déployé depuis 2010 sur une aire de près de 9 000 000 km2, le réseau d’hydrophones OHASISBIO fournit une base de données acoustiques multi-site et pluri-annuelle. L’application d’un algorithme de détection automatique des vocalisations de baleines bleues Antarctique, préalablement testé et validé, a permis d’établir les patrons géographiques et saisonniers de présence de l’espèce au sein du réseau. L’analyse systématique de ces vocalisations a également permis de caractériser des variations intra- et inter-annuelles de leur fréquence, affectée par une décroissance long-terme et des modulations saisonnières. L’analyse préliminaire de signatures vocales d’autres espèces présentes dans le réseau - rorquals communs et trois populations de baleines bleues pygmées – a révélé des variations de fréquence similaires de leur vocalisation et permis d’esquisser leurs patrons géographiques et saisonniers. Enfin, deux vocalisations, jusqu’alors non décrites, aux caractéristiques semblables à celles de baleines bleues, ont été identifiées et caractérisées<br>The Antarctic blue whale, Balaenoptera musculus intermedia, is currently critically endangered since the commercial whaling in the 20th century. The population recovery of this species, as well as its ecology, are still poorly known. Due to the ineffectiveness of visual observations, passive acoustics is a preferred method to monitor this highly vocal species. This dissertation presents an analysis of 7 years of passive acoustic monitoring in the southern Indian Ocean, known as a particularly important area of habitat and migration for the Antarctic blue whale. Deployed since 2010 over an area of about 9,000,000 km2, the OHASISBIO hydrophone network provides a multi-site and multi-year acoustic database. An algorithm for the automated detection of Antarctic blue whale calls, first tested and validated, has been applied to characterize the seasonal and geographic patterns of the species presence in the study area. The systematic analysis of these vocalizations also allowed to characterize intra- and inter-annual variations of their frequency, with a long-term decline and seasonal variations. A preliminary analysis of other vocal signatures recorded by the network, from 3 populations of pygmy blue whales and fin whales, highlighted similar variations of their frequencies and outlined their geographic and seasonal patterns of presence in the area. Finally, two previously undescribed vocalizations, with characteristics close to that of blue whale calls, were identified and characterized
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Hirzel, Lara. "Châteaux intérieurs : du théâtre de la mémoire aux espaces imaginaires." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLEE057/document.
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Châteaux intérieurs, du théâtre de la mémoire aux espaces imaginaires est une thèse composée de trois films, d’une installation vidéo et de deux scénarios. Ces travaux reposent sur des interrogations liées au lieu et à sa mémoire. Des mnémotechniques rhétoriques de l’antiquité aux usages du flashback dans le montage cinématographique, cette recherche traverse les champs de la photographie, des arts plastiques, de la littérature et du cinéma afin d’inventer ses propres usages plastiques de concepts philo- sophiques. Chaque projet développe sa façon propre d’aborder le sujet de la représentation d’un espace fantasmé, imaginé; façons liées au « genre » des propositions, à la place laissée au spectateur et, au cœur même des films, à la multiplicité des subjectivités des personnages. Ainsi, le film Demeure convoque saint Augustin et l’art de la mémoire tandis que Sirènes joue des effets de montage et de réminiscences. Les Passages secrets lie lieux réels et espaces fictionnels par l’installation in situ dans le village de Binic. La déambulation est alors une autre manière de rejouer le trajet discursif de la méthode des loci. Le scénario Sans Perceval, adapté des Vagues de Virginia Woolf, singularise quant à lui une multiplicité de points de vue sur un même temps partagé dans un lieu unique. D’une autre manière, Les Atomes joue avec la figure de la baleine comme lieu symbolique sur lequel achoppent et divergent les imaginaires. Enfin, en utilisant l’idée d’espace intérieur dans la fiction même, le projet des Châteaux intérieurs propose une voie d’actualisation d’anciennes propositions philosophiques et théologiques, autour d’une variation moderne du personnage de sainte Thérèse d’Avila. Ce dernier scénario agrège ainsi plusieurs concepts fréquemment évoqués, repris, mentionnés dans la topique chrétienne, ici distordus, transformés et utilisés dans la fiction même<br>The thesis Mind Palaces, from Memory Theatre to Imaginary Spaces is composed of three films, one video installation and two scripts. These works focus on questions of places and their memory. From ancient rhetorical mnemonics to the use of flashbacks in film editing, this study covers the fields of photography, fine arts, literature and film, in order to come up with its own artistic interpretation of philosophical concepts. Each project develops its own way of broaching the representation of a dreamt-up, imagined space; be it relating to the "genre" of proposals, to the role given to the audience, or, at the very heart of the films, to the multi- plicity of subjectivities of the characters. Thus, the film Remains evokes Saint Augustine and the art of memory, whilst Mermaids plays with various editing and reminiscence effects. Secret Passages links real places and fictional spaces through the in situ installation in the village of Binic, and the act of wandering therefore beco- mes another way of replaying the discursive journey in the method of loci. As for the Without Percival script, based on Virginia Woolf's The Waves, it differentiates between multiple points of view on a given moment shared in a single place. In a different way, Atoms plays with the whale as a symbolic place against which imaginations wash up and diverge. Finally, by using the idea of an interior space within the fic- tion itself, the Mind Palaces project provides a way of updating ancient philosophical and theological theories, based on a modern variation of Saint Teresa of Ávila. This last script combines a number of concepts that are frequently alluded to, revisited and mentioned in Christianity, and are here distorted, transformed and used in the fiction itself
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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<br>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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Nordeen, Carrie Louise. "The influence of high-amplitude acoustic deterrents on the distribution, abundance, and behaviour of baleen whales /." 2002.
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Valente, Raul Fonseca. "Looking for the migratory whales: Routes of the baleen whales in the Macaronesia." Dissertação, 2017. https://hdl.handle.net/10216/108013.
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Valente, Raul Fonseca. "Looking for the migratory whales: Routes of the baleen whales in the Macaronesia." Master's thesis, 2017. https://hdl.handle.net/10216/108013.
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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.
Full textAbstract:
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.<br>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.<br>Thesis written in co-mentorship with Robert Michaud.
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Santos, Margarida Bacelar Oliveira. "Distribuição e padrão de residência das Baleias-de-Barbas (Família Balaenopteridae) no Arquipélago dos Açores." Bachelor's thesis, 2008. http://hdl.handle.net/10400.3/202.
Full textAbstract:
Relatório de Estágio da Licenciatura em Biologia Marinha.<br>No arquipélago dos Açores encontram-se registadas seis espécies de baleias-de-barbas, todas pertencentes à Família Balaenopteridae, também designadas como rorquais: baleia-comum (Balaenoptera physalus), baleia-sardinheira (Balaenoptera borealis), baleia-azul (Balaenoptera musculus), baleia-anã (Balaenoptera acutorostrata), baleia-de-bossas (Megaptera novaeangliae) e baleia-de-Bryde (Balaenoptera edeni). A maioria destas espécies foi sobre-explorada e por isso encontra-se protegida a nível mundial. No entanto, a informação disponível sobre a ecologia destas populações e suas rotas migratórias é escassa, desconhecendo-se ainda o seu padrão de distribuição e residência na região. Recorrendo a saídas de mar (dedicadas e de oportunidade) desde 1988 a 2008 foi possível reunir bases de dados de foto-identificação e avistamentos destes animais. Estas bases de dados foram analisadas para determinar a ocorrência, distribuição, abundância relativa e habitats preferenciais. Com um total de 764 avistamentos, concluiu-se que a baleia-comum é a espécie mais abundante, com uma taxa de avistamento de 0,061 avistamentos/100 km. A baleia-de-Bryde foi considerada a espécie menos abundante (0,001/100km), uma vez que só foi avistada no Verão de 2004.
As três espécies mais abundantes, baleia-comum, baleia-sardinheira e baleia-azul exibiram variações significativas na sua ocorrência mensal, chegando ao arquipélago nos meses de maior produtividade primária. Foram também registadas flutuações significativas na abundância anual de indivíduos que parecem estar relacionadas com a disponibilidade de alimento.
O mapeamentos dos avistamentos permitiu constatar que as baleias se concentram em redor das ilhas e montes submarinos. Parecem também existir diferenças na concentração de indivíduos entre os diversos grupos de ilhas.
A análise das imagens de foto-identificação resultou num catálogo de 428 indivíduos, dos quais 153 foram considerados identificados. Entre os indivíduos identificados verificaram-se 24 reavistamentos, dois deles inter-anuais. Estes reavistamentos sugerem que as águas do arquipélago poderão ser utilizadas pelos animais como área de alimentação durante a migração. A baleia-de-bossas e a baleia-anã mostraram preferência por águas costeiras pouco profundas, enquanto que a baleia-sardinheira, baleia-comum e baleia-azul ocuparam uma maior diversidade de habitats, sendo encontradas tanto em ambiente oceânico como costeiro.
Os resultados deste trabalho demonstraram que as águas em redor do Arquipélago dos Açores poderão constituir um habitat importante para as baleias-de-barbas. ao possibilitar a recuperação de parte da energia dispendida durante a migração.
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Olio, Marília Pereira. "Temporal variability of cetaceans in the Azores and its relation with oceanographic features as derived by satellite imagery." Master's thesis, 2017. http://hdl.handle.net/10400.3/4637.
Full textAbstract:
Dissertação de Mestrado, Estudos Integrados dos Oceanos, 28 de abril de 2017, Universidade dos Açores.<br>O Arquipélago dos Açores (Portugal) é composto por nove ilhas vulcânicas no Nordeste Oceano Atlântico e detém uma elevada diversidade de cetáceos, com 28 espécies documentadas. Este é o primeiro estudo nos Açores, que avalia a utilidade de dados do turismo de observação de baleias para estudos científicos sobre a distribuição dos cetáceos, e que relaciona a sua ocorrência e variabilidade com imagens MODIS/AQUA de clorofila a (Chla) e temperatura à superfície (SST) com 1 km de resolução obtidas através do site da NASA Ocean Color. Neste estudo, cinco anos de dados de campo (2010-2014) foram utilizados para avaliar a presença das baleias azul, comum, sardinheira e bossas. Foram consideradas três escalas temporais (quatro anos em conjunto, anuais e mensais). Dado que o esforço não foi consistente ao longo dos anos, as taxas de avistamento (Encounter rate, ER=avistamentos.esforço-1) foram utilizadas como medidas padronizadas para comparações temporais de presença. Imagens diárias de Chla e SST foram processadas estatisticamente, obtendo-se médias mensais, sazonais, anuais, tendências e anomalias para o período de 2010 a 2014 para a região dos Açores e relacionados com a variabilidade local de quatro espécies de baleias de barbas para tentar explicar as diferenças registadas ao longo dos anos. Os principais resultados mostraram que a presença das quatro espécies de baleias de barbas nos Açores variou entre os anos. Diferenças intra-sazonais foram encontradas para as taxas de presença e estas variaram de acordo com a espécie. A presença de Bm foi observada durante a primavera sugerindo que estas baleias usam os Açores como área de alimentação durante estes meses enquanto estão na sua rota de migração para norte e que, a variação de Chla e o início do crescimento do fitoplâncton são bons indicadores do tempo efectivo destas na região. Resultados semelhantes foram encontrados para a BP, mas a sua associação com Chla e o momento do crescimento do fitoplâncton é posterior à Bm Sendo a Bp mais oportunista e tendo uma dieta mais variada, as suas presas podem estar a níveis diferentes cadeia alimentar. O pico de Bb variou nos meses de primavera e verão e estas diferenças podem ser explicadas pela suposição, já referida por outros autores, de que os Açores provavelmente são visitados por duas populações diferentes de Bb, uma durante a fase de migração na primavera e a segunda durante o final do verão e no outono. Assim sendo, a concentração de Chla seria um parâmetro biológico associado com o pico de Bb apenas para uma das populações. Por último, os picos de presença de Mn foram observados principalmente durante a primavera e o número de meses dos avistamentos duplicou em 2014 e 2015, sugerindo que Mn poderia utilizar os Açores como área de alimentação durante estes meses, durante o seu caminho de migração para norte. A temperatura da superfície do mar, a concentração de Chla e o início do crescimento do fitoplâncton, aqui ilustrados como médias gerais, médias ajustadas (tendências) e anomalias, suportam a hipótese de que o ciclo sazonal e a variabilidade inter-anual são bem demarcados nesta região podendo explicar as diferenças observadas na presença das baleias ao longo os anos. Ao remover o ciclo sazonal, SST é muito conservador ao longo dos anos, com uma ligeira tendência de aumento com o tempo. Com relação à Chla, nem todos os anos apresentam floração de primavera, mas 2010 e 2014 revelam os picos maiores de Chla, coincidindo também com um aumento global de observação das baleias, particularmente para 2014. O uso de plataformas de oportunidade pode dar aos cientistas um meio de recolha de dados sobre uma ampla gama de fauna marinha quando o financiamento da investigação é limitado. No entanto, face às limitações encontradas nos dados de cetáceos, este estudo apresenta novas sugestões de introdução nos protocolos de amostragem por forma a que os dados MONICET possam produzir dados detalhados para fins científicos.<br>ABSTRACT: The Archipelago of the Azores (Portugal) is composed of nine volcanic islands in the northeast Atlantic Ocean and it holds a high diversity of cetaceans, with 28 species documented. This is the first study in the Azores that assesses the utility of whale watching data for scientific studies on cetacean distribution, and that relates their occurrence and variability with 1 km resolution MODIS/AQUA near-surface chlorophyll a (Chla) and Sea Surface Temperature (SST) data obtained from NASA Ocean Color website. In this study, five years of field data (2010-2014) were used to evaluate blue, fin, sei and humpback whales presence. Three temporal scales (four years, yearly, and monthly) were considered. Given that effort was not consistent throughout, then encounter rates (ER=sightings.effort-1) were used as standardized measures for presence temporal comparisons. Daily satellite Chla concentrations and SST values were statistically processed such as to obtain monthly, seasonal, annual averages, trends and anomalies for the period 2010 to 2014 for the Azores region. Baleen whales presence was related with the oceanographic data to infer possible causes for whales inter-annual variability Main results showed that the presence of the four baleen whale species in the Azores varied among the years. Intra-seasonal differences were found for presence rates and these varied with the species. The Bm presence was observed during the springtime suggesting that they use the Azores for foraging activity during these months while they are in their migration journey to north and that the variation of Chla and the initiation of the bloom could determine their time in the area. Similar results were found for Bp but their association with Chla and the timing of the bloom is later than the Bm. Since Bp is more opportunistic and has a varied diet, this happened since their prey could be in another level of the food chain. The peak for Bb varied in the spring and summer months and these differences could be explained by the assumption previously made by other authors, that maybe the Azores is visited by two different stocks of Bb, one during the migration in spring time and the second during late summer and autumn. Furthermore, the Chla concentration could be a biological parameter associated with the peak of Bb only for one stock. Lastly, the presence peaks of Mn were observed mostly during the spring and the number of sightings per month doubled in 2014 and 2015, suggesting that Mn could have foraged during these months while they were in their migration journey to north. Sea surface temperature and Chla concentration overall averages, adjusted averages (trends) and anomalies, as well as, calculations of the timing of the blooms show that the seasonal cycle is strong at these latitudes and inter-annual variability may explain differences in whales presence over the years. By removing the seasonal cycle, SST is very conservative over the years, and its trend reveals slight increase with time. Regarding Chla concentrations, spring blooms are not always observed in the region, but 2010 and 2014 reveal the strongest ones, coincident also with an overall increase in baleen whales observation, particularly for 2014. The use of platforms of opportunity may provide scientists a means of collecting data on a wide range of marine fauna when research funding is limited. Nevertheless, and in face with all the limitations found in the cetacean data, this study presents new suggestions for sampling protocols improvement such data from whale watching in MONICET might yield better possibilities for scientific purposes in the Azores.
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Thomas, T. A. "Behaviour and habitat selection of bowhead whales (Balaena mysticetus) in Northern Foxe Basin, Nunavut." 1999. http://hdl.handle.net/1993/2427.
Full textAbstract:
This is the first study of the behaviour and habitat preferences of bowhead whales ('Balaena mysticetus') in northern Foxe Basin, Nunavut, Canada. The study is divided into two parts; the first part examined the characteristics of bowhead habitat and the second part describes the behaviour of bowheads during the ice-edge season. Characteristics of bowhead habitat were identified by quantifying relationships between habitat variables (water depth, surface temperatures, ice conditions, and zooplankton densities) and the distribution of whales recorded during strip-transect surveys through a 4 x 4 km quadrat system, in July and August 1997. Two study areas were examined: "A" was examined in July (ice-edge season), when land-fast ice was present on the northern edge of the study area and "B" was examined in August (open-water season), when pack ice is present. Relationships between habitat variables and whale distribution were identified with Mantel tests. The second part of the study examined the behavior of bowheads during the ice-edge. (Abstract shortened by UMI.)
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Cheoo, Gisela Vitória. "Estimation of bowhead whale (Balaena mysticetus) population density using spatially explicit capture-recapture (SECR) methods." Master's thesis, 2018. http://hdl.handle.net/10451/39109.
Full textAbstract:
Tese de mestrado em Bioestatística, Universidade de Lisboa, Faculdade de Ciências, 2019<br>Management and conservation of wildlife populations is a major concern. Population density is a key ecological variable when making adequate decisions about them. A variety of methods can be used for estimating density. Capture-recapture (CR, also known as mark- recapture) methods are a popular choice, but ignoring the spatial component of captures has historically led to problems with resulting inferences on abundance. Spatially explicit capture- recapture (SECR) methods use the spatial information to solve two key problems of classical CR: defining a precise study area where captures occur over and reducing un modeled heterogeneity in capture probabilities. Arrays of Directional Autonomous Sea floor Acoustic Recorders (DASARs) recorded calls from the Bearing-Chukchi-Beaufort (BCB) population of bowhead whales during the autumn migration. The available passive acoustic data set was collected over 5 sites (with 3–13 sensors per site) and 8 years (2007–2014), and then processed via both automated and manual procedures. The automated procedure involved computer-processing by a multi-stage detection, classification and localization algorithm. In the manual procedure, calls were detected and classified by trained staff who manually listened to the recordings and examined spectrograms. The resulting manual data presents some pitfalls for density estimation, including non-independence among sensors caused by human intervention. The non-independence leads to an excess of calls being detected in all DASARs on a site. Data from the automated procedure does not suffer the non-independence issue, but the amount of ’singletons’ is approximately 15 times higher than in the manual data. ’Singletons’ are calls detected exclusively in one sensor and we assume they mostly comprise false positives. False positives are sounds classified as coming from the species of interest, but in reality are something else. Considering only automated data from 2013 and 2014, several approaches were performed to solve the excess of singletons. Density estimation with a standard SECR analysis was conducted according to the following approaches: i)ignoring the singletons problem and analyzing all calls; ii) removing the singletons; and iii) discarding a proportion of 1 – p false positives from the singletons. Simulated results were compared to verify the best approach. We also discuss a new approach by developing a SECR likelihood function that accommodates truncation of certain acoustic cues, specifically singletons. We have laid foundations for the analysis of this data set, but there are other possible research avenues to explore. Our next steps would include embedding additional information (like received levels and bearing angle) in the SECR formulation.
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Carvalho, Inês. "Population structure of humpback whales (Megaptera novaeangliae) in west coast of Africa." Master's thesis, 2012. http://hdl.handle.net/10400.1/12188.
Full textAbstract:
A baleia corcunda (Megaptera novaeangliae) é uma das espécies mais conhecidas e mais facilmente identificáveis das grandes baleias. Tal como os outros misticetos, as baleias corcunda têm um ciclo de vida marcadamente sazonal, passando o Inverno em águas costeiras quentes nos trópicos, onde acasalam e têm as crias, migrando depois para zonas frias de grande produtividade onde se alimentam. No hemisfério sul ocorrem várias populações de baleias corcunda. O presente trabalho contribui para um maior conhecimento da biologia e estrutura populacional das baleias corcunda que ocorrem na costa oeste africana (stock B - Comissão Baleeira Internacional) desde o Golfo da Guiné (região B1) até à Africa do Sul (região B2). Foi utilizada uma abordagem metodológica multidisciplinar, tendo por base estudos a nível local e regional, focando sobretudo aspectos ligados aos padrões temporais e espaciais desta população. Com base num extenso conjunto de dados de ADN mitocondrial e microssatélites, verificou-se a existência de uma
estruturação tanto a nível temporal como espacial entre as duas regiões. Surgiram igualmente vi
diferenças ao nível da fidelidade ao local e no sex ratio. Mais, os animais que estão presentes durante os meses de Verão na costa oeste da África do Sul são os que mais contribuem para esta diferenciação. Em conjunto, estas evidências sugerem que uma parte das baleias que se alimenta na África do Sul pertence a uma área de reprodução desconhecida. A importância da temperatura da superfície do mar na distribuição destes animais nesta área foi demonstrada a nível local e regional. Este estudo descreveu ainda, pela primeira vez, as características das baleias corcundas na ilha de São Tomé e descobriu que esta região é utilizada sobretudo por pares mães-cria, como zona de nascimento ou descanso, facto que sugere que esta pode ser uma zona importante do ponto de vista da conservação nesta região.
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Nieukirk, Sharon L. "Satellite monitored dive characteristics of the northern right whale, Eubalaena glacialis." Thesis, 1992. http://hdl.handle.net/1957/36164.
Full textAbstract:
The western North Atlantic population of the northern right whale (Eubalaena
glacialis) was severely depleted by whaling over the last century. Despite over fifty
years of protection, fewer than four hundred individuals are believed to exist in the
North Atlantic. Relatively little is known about the diving behavior, respiratory
physiology, or diel activity of these whales, although such information could be useful
in predicting population abundance and distribution in relation to food or
environmental variables. Dive behavior data can be collected visually, but collection
is limited to daylight hours, calm weather, and fortuitous encounters with study
animals. Satellite-monitored radio tags offer the opportunity to collect data on
individual whales' diving behavior continuously, over long distances and periods of
time, and at relatively low cost.
Thirteen North Atlantic right whales were tagged and monitored in the Gulf of
Maine between 1989 and 1991. One male was tagged in 1989; two adult males, six
adult females (two with calves) and one juvenile were tagged in 1990; one adult
female (with a calf) and two juveniles were tagged in 1991. The duration of
monitoring for the whales varied from <1 day to 43 days. Characteristics of the
radio tags were different over each year in order to evaluate different attachment
mechanisms and methods of collecting and summarizing data for dive duration, dive
frequency, and time submerged. These data were then used to describe the dive
behavior and to predict aspects of the respiratory physiology for these whales.
The number of dives, their duration, and the time submerged varied
considerably among individual whales and between years. Over all, the whales spent
79% of their time underwater. However, most dives were short (i.e., 95% were
<14 min; the mean dive duration was 92.3 sec), although dives of 30-40 min
duration were observed for several individuals. In general, the number of dives a
right whale made was inversely related to the average duration of its dives within a
time interval. Furthermore, over a given time interval, the number of times a whale
dove was a better predictor of the percent time it was submerged than was the
average duration of its dives.
There was no evidence of diel variation in dive behavior (i.e., number of
dives, average dive duration, or percent time submerged) among these whales. Age,
sex, and reproductive status may have affected dive behavior, although these trends
were not statistically significant due to the small number of study animals and
individual behavioral variability. Males tended to dive more often and averaged
shorter dives than females. Females with calves dove more often and averaged
shorter dives than females without calves. Juvenile females dove less often but
averaged longer dives than adult males or females with calves.
It was predicted that the aerobic dive limit of an "average" right whale was
approximately 14 min. Ninety-five percent of the dives recorded for the 11
monitored right whales were < 14 min. Furthermore, there was no evidence of
recuperative periods (i.e., prolonged periods at the surface) after long dives. These
observations were consistent with the idea that the North Atlantic right whales dove
within their aerobic scope. They further suggest that physiological parameters alone
probably have little influence on dive characteristics, except to set an upper limit on
the duration of a dive.
Satellite telemetry provides an opportunity to monitor the movements and
behavior of free-ranging animals, and overcome many of the short-comings associated
with traditional, human-based visual techniques for tracking and studying such
animals. Although the tags used in this study were prototypes and varied in their
design from year to year, several right whales were monitored simultaneously and
were tracked over thousands of kilometers. Advances in tag miniaturization,
attachment, and software will likely extend the time tags stay attached and the detail
of the behavioral and environmental variables that can be monitored. As testimony to
the power of this technology, this application of satellite telemetry to monitor great
whales yielded one of the most extensive, long-term, continuously-monitored data sets
yet recorded on the diving behavior of a baleen whale.<br>Graduation date: 1993