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. / 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.

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. / 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.

The spatial distribution of four species of rorqual whales was studied along the north shore of the Gulf of St. Lawrence during the months of June to October from 1989 to 2000. A research effort of 6511 hours at sea yielded 849 sightings of blue whales (Balaenoptera musculus), 5291 of finback whales (Balaenoptera physalus), 3822 of humpback whales (Megaptera novaeangliae) and 6489 of minke whales (Balaenoptera acutorostrata). Spatial and behavioural data were collected at sea using inflatable boats, and Global Positioning Systems (GPS) were used to obtain accurate positions. These data were plotted and analysed using a Geographic Information System (GIS) to test the hypotheses that patterns of distribution were not random, were associated with bathymetry and reflected specific differences in habitat use. The resulting maps illustrated the clustered distribution of rorqual whales linked to sea-bottom topography, probably associated with areas of local upwelling and increased productivity. Blue and fin whales shared almost the same distribution, humpback whales were found in slightly deeper, offshore waters whereas minke whales were more abundant in shallower waters. Little attention has been given until now to local patterns of distribution in the area and such information can be useful for practical management considerations. The results emphasise the importance of scale in ecological studies of marine mammals and the need for further research using additional oceanographic parameters, in order to better understand habitat selection.

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. / 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.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-03-30T19:57:50Z No. of bitstreams: 1 marialuizapachecodegodoy.pdf: 947462 bytes, checksum: 7f3440dade9193ef6c9954130cbfbd98 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-04-03T19:00:23Z (GMT) No. of bitstreams: 1 marialuizapachecodegodoy.pdf: 947462 bytes, checksum: 7f3440dade9193ef6c9954130cbfbd98 (MD5) / Made available in DSpace on 2017-04-03T19:00:23Z (GMT). No. of bitstreams: 1 marialuizapachecodegodoy.pdf: 947462 bytes, checksum: 7f3440dade9193ef6c9954130cbfbd98 (MD5) Previous issue date: 2007-03-27 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / 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. / 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.

Small-scale wind turbines were not considered viable in the past due to their poor efficiencies, mainly because of their aerodynamic effects around the irfoil shape. Recently researchers have renewed interest in enhancing the aerodynamic performances of the blades’ designs inspired by the aerodynamic pattern of biological characteristics of insects and marine mammals such as locusts, dragonflies, damselflies, Humpback Whales etc. Bioinspired wing designs have advantages compared to conventional smooth irfoil blades as they can counter the bending forces that the wings experience during flapping. Bio-inspired corrugated airfoil based on dragonfly wing geometries have been reported to perform well compared to conventional airfoil at low Reynolds numbers. Corrugated airfoils reduce flow separation and enhance aerodynamic performance by trapping vortices in the corrugations thus drawing flow towards the airfoil’s surface. This results in the higher lift whilst incurring only marginally higher drag. Such airfoils also have an advantage when it comes to span-wise structural stiffness due to the corrugated cross-sections. Replacing conventional turbine blades by tubercles or corrugated blades could enhance turbine performance by reducing the pressure gradient along the leading edge; however, the aerodynamic effects at the leading edge will depend on the variations of wavelength and amplitude. In this study, two types of computational studies were investigated: Optimising a corrugated airfoil and investigating the aerodynamic effects of a sinusoidal shape at the leading edge of a blade. Previous studies used an idealized geometry based on the dragonfly wing cross-section profile but did not attempt to optimize the geometry. In the present study: a two-dimensional CFD model is constructed using ANSYS Fluent Workbench-Design Explorer to determine the optimal corrugated blade profile for four angles of attack (AOA) from 5° to 20° corresponding to typical AOA of small-scale wind turbine blades. Two modified blades with variations of wavelength and amplitude at the leading edge were studied to investigate the aerodynamic effects. Three-dimensional models were constructed using Qblade software and 3D points were exported to AutoCAD Inventor to generate the CAD model. The governing equations used are continuity and Navier-Stokes equations written in a frame reference rotating with the blade. The CFD package used is ANSYS FLUENT 19.0. The simulation was run under steady-state, using SST-k omega turbulence model. The modifications have improved the aerodynamic performance. The optimised corrugated blade produced a maximum increase of CL and L/D. Both modified blades (1 and 2) had their performances measured separately and compared to that of baseline blade SG6042 (Conventional blade). Modified blade 1 had a lower wavelength and amplitude at the leading edge of 14.3 % and 4 % respectively of the chord. It was noted that the aerodynamic performance decreased by 6%. Modified model 2, on the other hand had a higher wavelength and amplitude at the leading edge. of 40.4 % and 11.9 % respectively of the chord. It was also noted the aerodynamic performance increased by 6%. From the empirical evidence highlighted above, it can be observed that there is a direct correlation between wavelength, amplitude, and aerodynamic performance of the blade. / Electrical and Mining Engineering / M. Tech. (Engineering)

No description available.

As the understanding of the workings of the biological world expands, biomimetic designs increasingly move into the focus of engineering research studies. For this thesis, two studiesinvolving leading edge vortex generation for lift production as observed in nature were explored intheir respective flow regimes. The first study focused on the steady state analysis of streamwise vortices generated byleading edge tubercles of an adult humpback whale flipper. A realistic scaled model of a humpbackflipper was fabricated based on the 3D reconstruction from a sequence of 18 images taken whilecircumscribing an excised flipper of a beached humpback whale. Two complementary modelswith smooth leading edges were transformed from this original digitized model and fabricatedfor testing to further understand the effect of the leading edge tubercles. Experimentally-obtainedforce and qualitative flow measurements were used to study the influence of the leading edgetubercles. The presence of leading edge tubercles are shown to decrease maximum lift coefficient(Cl ), but increase Cl production in the post-stall region. By evaluating a measure of hydrodynamicefficiency, humpback whale flipper geometry is shown to be more efficient in the pre-stall regionand less efficient in the post-stall region as compared to a comparable model with a smooth leadingedge. With respect to a humpback whale, if the decrease in efficiency during post-stall angles ofattack was only required during short periods of time (turning), then this decrease in efficiencymay not have a significant impact on the lift production and energy needs. For the pursuit ofbiomimetic designs, this decrease in efficiency could have potential significance and should beinvestigated further. Qualitative flow measurements further demonstrate that these force results aredue to a delay of separation resulting from the presence of tubercles.The second study investigated explored the effects of flapping frequency on the passive flowcontrol of a flapping wing with a sinusoidal leading edge profile. At a flapping frequency of f =0.05 Hz, an alternating streamwise vortical formation was observed for the sinusoidal leading edge,while a single pair of vortices were present for the straight leading edge. A sinusoidal leading edgecan be used to minimize spanwise flow by the generation of the observed alternating streamwisevortices. An increase in flapping frequency results in these streamwise vortices becoming stretchedin the path of the wing. The streamwise vortices are shown to minimize spanwise flow even afterbeing stretched. Once instabilities are formed at f ≥ 0:1 Hz due to velocity shearing generatedby the increase in cross-radial velocity, the alternating streamwise vortices begin to break downresulting in a increase of spanwise flow.

Made available in DSpace on 2014-12-17T15:36:39Z (GMT). No. of bitstreams: 1 MarcosRRS_TESE_2red.pdf: 2914202 bytes, checksum: 607aa226333ce661d0e57d380f43b9e9 (MD5) Previous issue date: 2012-08-07 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / 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 / 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

No description available.