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1
Robbins, Julie. "Structure and dynamics of the Gulf of Maine humpback whale population/." St Andrews, 2007. http://hdl.handle.net/10023/328.
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Rotaru-Varga, Adam. "Computer modelling of humpback whale foraging behaviours." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0012/MQ61489.pdf.
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Witteveen, Briana Harmony. "Using stable isotopes to assess population structure and feeding ecology of North Pacific humpback whales (Megaptera novaeangliae)." Orlando, Fla. : University of Central Florida, 2008. http://purl.fcla.edu/fcla/etd/CFE0002386.
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Robbins, J. "Structure and dynamics of the Gulf of Maine humpback whale population." Thesis, University of St Andrews, 2007. http://hdl.handle.net/10023/328.
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Population structure and vital rates of Gulf of Maine (GOM) humpback whales, Megaptera novaeangliae, were studied by a combination of longitudinal data, region-wide surveys and modern mark-recapture statistical methods. Demography and rates of exchange were examined among six GOM areas. Juveniles and females were preferentially encountered in southern GOM habitats, including at the Studds Stellwagen Bank National Marine Sanctuary (SBNMS). Multi-state modelling also revealed unequal probabilities of movement between areas that was not explained by inter-area distance, adjacency, whale density or dominant prey type. Aerial surveys and photo-identification data indicated that the population was likely closed to migration between June and September. Otherwise, seasonal trends in population composition were consistent the demographically staggered migration reported in other oceans. Over-wintering occurred,but there was little evidence that a significant number of humpback whales failed to undertake or complete migration each year. Vital rates varied with sex, age and time. Juveniles exhibited lower and more variable survival than adults and so were a potential source of downward bias in “non-calf” survival estimates. Males exhibited higher survival than females and achieved maximal survival at age five, the estimated age at male puberty. By contrast, females did not reach peak survival until the current average age at first birth (8.78 years, s = 2.33). The latter was significantly higher than previous estimates and females that recruited by age seven had a lower likelihood of subsequent survival than those that recruited late. Costs of reproduction persisted into adulthood, with breeders exhibiting lower survival than nonbreeders. Calves born during years of low fecundity exhibited lower survival than those born when fecundity was high, possibly due to lower maternal investment. Costs of reproduction have not previously been described in cetaceans, but are consistent with the risks potentially associated with capital breeding.
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Stamation, Kasey Anne Biological Earth & Environmental Sciences Faculty of Science UNSW. "Whale-watching in NSW: research to integrate the needs of whales, tourists and industry." Publisher:University of New South Wales. Biological, Earth & Environmental Sciences, 2009. http://handle.unsw.edu.au/1959.4/43726.
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This thesis examines the human and animal dimensions of whale-watching and develops a framework for management of the humpback whale-watching industry in New South Wales (NSW), Australia. The short-term responses of humpback whales to whale-watching vessels during their southward migration on the south coast of NSW were assessed. The behaviour of pods was recorded from commercial whale-watching vessels during tours and compared to pods in the absence of vessels observed from shore in the same area. Pod sizes and composition were typical of southward migrating whales. Calf pods were more sensitive to the presence of vessels than non-calf pods. Whilst there was a longer dive time and a greater percentage of time spent submerged by whales in the presence of vessels, there were no associated changes in respiration intervals. Some surface behaviours were suppressed in the presence of vessels. Surface-active behaviours were prevalent in this study which indicates that social interactions amongst conspecifics are common during the southern migration. Feeding pods were observed on 24.5% of all whale-watching trips and during 14% of all observations made from shore. South-eastern NSW is probably a significant supplemental feeding ground for migrating whales. Feeding behaviour did not alter in the presence of vessels but the time between feeding lunges increased when vessels were closer than 100 m and when more than one vessel was present. The demographics, expectations, experience and satisfaction of land-based and boat-based whale-watchers in NSW were assessed by a questionnaire to participants. Land-based whale-watchers had high and often unrealistic expectations about their whale-watching experience and were moderately satisfied. Boat-based whale-watchers had high, but often realistic expectations of their experience and were highly satisfied. Satisfaction was a function of the degree to which expectations were met, the proximity of whales, the numbers of whales, their behavioural displays and the level of information available on whales. Whale-watchers showed limited increase in their knowledge and conservation-oriented behaviours over the long term. Current education about whales requires better structure and clearer conservation objectives. This study identifies research, education and vessel management as three fundamental components for the sustainable management of the whale-watching industry, and makes recommendations incorporating these components.
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Sharpe, Fred. "Social foraging of the southeast Alaskan humpback whale, Megaptera novaengliae." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ61679.pdf.
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Valsecchi, Elena. "Genetic analysis of the humpback whale (Megaptera novaeangliae) using microsatellites." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242544.
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Custodio, Derrick. "The Effect of Humpback Whale-Like Protuberances on Hydrofoil Performance." Digital WPI, 2012. https://digitalcommons.wpi.edu/etd-dissertations/183.
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The humpback whale is very maneuverable despite its enormous size and rigid body. This agility has been attributed to the use of its pectoral flippers, along the leading edge of which protuberances are present. The leading edge protuberances are considered by some biologists to be a form of passive flow control and/or drag reduction. Force and moment measurements along with qualitative and quantitative flow visualizations were carried out in water tunnel experiments on full-span and finite-span hydrofoil models with several different planforms and protuberance geometries. A NACA 634-021 cross-sectional airfoil profile was used for the baseline foil in all tests. Four planform geometries chosen included: a full-span set of foils which spanned the breadth of the water tunnel, a finite-span rectangular planform, a finite-span swept hydrofoil, and a scale flipper model that resembled the morphology of the humpback whale flipper. A variety of sinusoidal protuberance geometries which included three amplitudes equal to 2.5%, 5%, and 12% and wavelengths of 25% and 50% of the local chord were examined in combination with the different planform geometries. Testing included force and moment measurements and Particle Image Velocimetry (PIV) to examine the load characteristics and flow field surrounding the modified foils. Load measurements show that modified foils are capable of generating higher lift than the baseline at high angles of attack while at low angle of attack the baseline generally produces a lift coefficient equal to or greater than the modified cases. With the exception of the modified flipper model, the drag coefficients of the modified hydrofoils are either equal to or greater than their baseline counterparts. The increased drag reduces the lift-to-drag ratio. Flow visualizations show that vortical structures emanating from the shoulders of the protuberances are responsible for increased lift and drag at high angles. Cavitation tests show that modified foils cavitate in pockets behind the troughs of protuberances whereas the baseline foils produce cavitation along the entire foil span. Also, the cavitation numbers on modified hydrofoils were consistently higher than their baseline counterparts. This work shows the effect of leading edge protuberances on the aforementioned performance characteristics.
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Custodio, Derrick S. "The Effect of Humpback Whale-like Protuberances on Hydrofoil Performance." Digital WPI, 2007. https://digitalcommons.wpi.edu/etd-theses/1111.
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"Despite its size the humpback whale is extremely maneuverable. This has been attributed to their use of pectoral flippers, along which protuberances are present along the leading edge. There has been speculation that the protuberances along the leading edge of the pectoral flipper act as a form of passive flow control. To examine the effects of protuberances on hydrofoil performance, the lift, drag, and pitching moments of two-dimensional hydrofoils with leading edge sinusoidal protuberances were measured in a water tunnel and compared to those of a baseline NACA 634-021 hydrofoil. The amplitude of the protuberances ranged from 2.5% to 12% of the mean chord length and the spanwise wavelengths were 25% and 50% of the mean chord length. This corresponds to the morphology found on the leading edge of humpback whale’s flippers. Flow visualization using tufts and dye was also performed to examine the near surface flow patterns surrounding the hydrofoils. At angles of attack lower than the stall angle of the baseline the modified foils revealed reduced lift and increased drag. However, above this angle the lift generated by the modified foils was up to 50% greater than the baseline foil with little or no drag penalty. The amplitude of the protuberances has a large effect on the performance of the hydrofoils whereas the wavelength has little. Corroborating lift and drag measurements, visualizations show attached flow on the peaks of the protuberances and separation in the valleys at angles beyond the stall angle of the baseline foil."
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Brasseur, Muriel M. "Population structure and management of the humpback whale (Megaptera novaeangliae) in Western Australia : investigation of the genetic status and structure of stock D/Antarctic area group IV." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2007. https://ro.ecu.edu.au/theses/299.
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The subpopulation of humpback whales that migrates along the coast of Western Australia (Stock D or Antarctic Area Group IV), along with other Southern Ocean stocks, were left severely depleted as a result of commercial whaling during the last century. While several studies have been carried out to ascertain the D Stock's status by way of population dynamics, photo-identification and aerial surveys, there has been no study focussing on this subpopulation in terms of genetics and little is known in terms of its population structure. This thesis aims to define this stock via a thorough, post-whaling investigation of its genetic status and structure.
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Banks, Aaron M. "The seasonal movements and dynamics of migrating humpback whales off the east coast of Africa." Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/4109.
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Data collected during boat-based and aerial surveys were used to describe population structure, movements, temporal patterns of migration and skin condition of humpback whales in breeding sub-stock C1-S off southern Africa. Results confirmed that the migration route along the south coast of South Africa is linked to the winter ground off Mozambique. A lack of exchange between breeding sub-stocks C1-N and C1-S was found, suggesting that these are independent of each other. Molecular analysis revealed unexpected levels of population structure between the migration route and the winter ground of C1-S, as well as the possibility that this migration route is also utilised by some individuals from breeding sub-stock C3. A skin condition of unknown aetiology that primarily affects humpback whale mother-calf pairs was identified. The first assessment of its prevalence and severity was made, providing a baseline for future monitoring. Humpback whale abundance in an inshore region of Bazaruto Archipelago, Mozambique was estimated and attempts were also made to use the limited information off Plettenberg Bay/Knysna, South Africa. In addition to improving our understanding of humpback whales from Breeding Stock C, knowledge about another baleen whale species utilising the southwest Indian Ocean was extended. The first evidence of southern right whale presence off the coast of Mozambique since the cessation of whaling was documented. It remains unknown whether this is a remnant sub-stock or the recovering South African sub-stock reoccupying its historical range.
12
Fineman, Rachel L. "An interdisciplinary examination of whalewatching in Stellwagen Bank National Marine Sanctuary and Hawaiian Islands Humpback Whale National Marine Sanctuary /." Connect to online version, 2005. http://ada.mtholyoke.edu/setr/websrc/pdfs/www/2005/131.pdf.
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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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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
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.
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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Pace, Federica. "Automated classification of humpback whale (Megaptera novaeangliae) songs using hidden Markov models." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/364358/.
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Humpback whales songs have been widely investigated in the past few decades. This study proposes a new approach for the classification of the calls detected in the songs with the use of Hidden Markov Models (HMMs). HMMs have been used once before for such task but in an unsupervised algorithm with promising results. Here HMMs were trained and two models were employed to classify the calls into their component units and subunits. The results show that classification of humpback whale songs from one year to another is possible even with limited training. The classification is fully automated apart from the labelling of the training set and the input of the initial HMM prototype models. Two different models for the song structure are considered: one based on song units and one based on subunits. The latter model is shown to achieve better recognition results with a reduced need for updating when applied to a variety of recordings from different years and different geographic locations.
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Burkard, Michael. "Humpback Whale Cell Lines as an In Vitro Tool for Toxicity Assessment." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/367059.
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Persistent Organic Pollutants (POPs) are predominantly anthropogenically-derived chemicals, characterized by their persistence, toxicity, capacity for bioaccumulation and tendency for long-range environmental transport. They have been observed at elevated concentrations in polar environments and biota, including Antarctic foraging humpback whales (Megaptera novaeangliae). Southern hemisphere humpback whales are highly dependent on lipid reserves accumulated during summer feeding to sustain their seasonal migration and associated period of voluntary fasting, the longest known in any mammal. This extreme life-history behaviour has been observed to result in a dramatic increase in blubber POP concentrations and presumed circulating lipophilic POP burdens during times of negative energy balance. Toxicological investigations of the effect of circulating POP burdens are, however, constrained by logistical challenges associated with large cetacean research, and the limitations of existing non-lethal research approaches.This thesis research was designed to develop a humpback whale derived fibroblast cell culture for species-specific assessment of the toxicological impact of priority POPs and other potential stressors.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environemnt
Science, Environment, Engineering and Technology
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Hatum, Paula Sobenko. "The song of humpback whale and the potential effects of whale-watching in the abrolhos bank, BA, Brazil." Universidade Federal do Rio Grande do Norte, 2015. http://repositorio.ufrn.br/handle/123456789/21081.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Os machos de baleia jubarte, Megaptera novaeangliae, produzem uma longa e complexa sequ?ncia de sons, denominada canto, que podem ser definidas em uma estrutura hier?rquica, consistindo de subunidades e unidades, subfrases e frases, temas, canto e sess?es de canto. O canto ocorre predominantemente em ?reas de reprodu??o, no entanto, machos tamb?m cantam, por?m com menor ocorr?ncia, em ?reas de alimenta??o e durante a migra??o. A fun??o do canto ainda n?o ? bem compreendida, por?m, entre muitas hip?teses propostas, as teorias predominantes s?o de que os machos cantam para atrair as f?meas, ou para estabelecer e/ou manter domin?ncia entre machos.n. Inicialmente descritos como padr?es fixos, estudos subsequentes mostraram que o canto est? sob frequentes mudan?as ao longo de uma ou mais esta??es reprodutivas dentro de uma popula??o. Este processo tem sido referido como um exemplo de evolu??o cultural. Desde o in?cio da morat?ria ? ca?a, muitas popula??es de baleias v?m se recuperando em todo o mundo e, no Brasil, acompanhando o aumento da ocorr?ncia das baleias jubarte, o turismo de observa??o (Whale-Watching) desta esp?cie vem se tornando cada vez mais frequente no estado da Bahia. Embora permita uma utiliza??o mais sustent?vel das jubartes como um recurso natural, o r?pido crescimento desse tipo de turismo vem gerando preocupa??o sobre os poss?veis efeitos que a atividade pode causar na esp?cie, em especial nas ?reas de reprodu??o, como ? o caso do Banco dos Abrolhos, litoral sul da Bahia, principal ?rea de reprodu??o da esp?cie no oeste do Oceano Atl?ntico Sul. Todas as embarca??es, desde os menores barcos at? os grandes petroleiros, produzem ru?dos, os quais variam com as caracter?sticas das mesmas. Estudos investigando as poss?veis respostas da baleia jubarte frente ? aproxima??o de embarca??es verificaram que a dura??o de alguns elementos do canto foi alterada, podendo at? mesmo levar ? interrup??o do comportamento vocal em per?odos de tr?fego intenso ou t?m seus cantos mascarados pelos ru?dos das embarca??es, o que pode ser um problema para detec??o e localiza??o de machos cantores e comunica??o entre as baleias. As consequ?ncias dessa ruptura no sistema de comunica??o podem resultar em graves efeitos sobre o sucesso de acasalamento individual, podendo at? mesmo, em longo prazo, causar efeitos na viabilidade das popula??es. Este trabalho tem como objetivo (1) analisar a varia??o na estrutura do canto das baleias jubartes no Banco dos Abrolhos durante o per?odo de 2003-2005, descrevendo as varia??es encontradas no n?vel hier?rquico de frases, e, definir linhagens de temas ao longo deste per?odo; (2) comparar o comportamento vocal de machos de baleia jubarte na presen?a e na aus?ncia de barcos a motor associados ? atividade tur?stica na regi?o do banco dos Abrolhos; e, (3) caracterizar os ru?dos das embarca??es e identificar as caracter?sticas dos barcos que influenciam nas respostas comportamentais das baleias jubarte. Vinte e um temas foram descritos entre o per?do de 2003 e 2005. Linhagens de continuidade foram definidas para temas nos quais haviam frase padr?o definida atrav?s de teste estat?stico. Foram observadas mudan?as na estrutura espectral das unidades, a introdu??o de novas unidades, unidades de remo??o e tamb?m varia??o na estrutura geral senten?a intra e inter-individual. No cap?tulo 2, o canto foi adquirido sem a presen?a de barco a motor e durante a aproxima??o de um ?nico barco a motor, o qual se aproximava seguindo as diretrizes para as atividades de "whale watching" nesta ?rea. Os resultados mostraram que embora o n?mero de frases por tema diminuam na presen?a de barco, esta diferen?a n?o ? significativa. Similarmente, a dura??o da frase tamb?m ? mantida mesmo durante a exposi??o ao ru?do de barcos a motor, o que sugere que esta m?trica deve ser importante para a comunica??o de machos reprodutivos e deve apresentar uma forte press?o seletiva para manter sua consist?ncia. Finalmente, no terceiro cap?tulo, os resultados sugerem que os sons produzidos pelos diferentes tipos de embarca??es neste estudo (veleiro e traineiras) e os diferentes tipos de motor (motor de popa e motor interior), parecem n?o ter qualquer influ?ncia no comportamento ac?stico ou espacial das jubartes. Al?m disso, os valores encontrados para as m?tricas utilizadas (3 dB bandwidth e source level) na caracteriza??o dos ru?dos produzidos pelas diferentes embarca??es, parecem n?o apresentar nenhuma associa??o com os diferentes tipos de barcos de turismo considerados na an?lise. No entanto, 71 % (n = 7) das embarca??es apresentaram valores de 3 dB bandwidth que se sobrep?e as frequencias utilizadas no canto dos machos de baleia jubarte, sugerindo o poss?vel mascaramento das vocaliza??es das baleias. Devido ? import?ncia da comunica??o ac?stica para as baleias jubarte, faz-se necess?rio compreender melhor os processos envolvidos na evolu??o do canto da esp?cie, bem como a melhor compreens?o dos poss?veis efeitos provocados pelos ru?dos das embarca??es sobre as baleias jubartes que podem fornecer informa??es relevantes na tomada de decis?es para a conserva??o e o melhor gerenciamento do turismo de observa??o das jubartes no Parque Nacional Marinho dos Abrolhos, ambiente de extrema import?ncia para a esp?cie.
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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 mèreIn 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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McCaslin, Lauren E. "Documenting Marine Mammal Behavior and Evaluating the Benefits and Consequences of Viewing Marine Mammals in Southcentral Alaska." TopSCHOLAR®, 2019. https://digitalcommons.wku.edu/theses/3128.
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Marine mammals are in a precarious conservation position because of anthropogenic impacts and historic perceptions that they are a consumable commodity. In light of changing abiotic conditions, further evaluation is needed on the habitat use, behavior, and interactions among marine mammals. Conservation legislation has helped protect species, but the greatest ground swelling may be the advent of the commercial whale watching industry. The feeding grounds in Alaskan waters have made this area a prime tourism location, and these nutrient-rich waters have resulted in a confluence of marine mammal species, including the appealing and abundant humpback whale (Megaptera novaeangliae) that may associate with three ecotypes of killer whales (Orcinus orca). These species are interesting because they may travel together to feed on prey or be adversaries in a predator-prey relationship. Using whale watching as a platform, this study evaluated the effects of the presence of these two species separately and together, and of the type of interaction between them, on human perception. Data were collected via opportunistic observations and a retrospective pre- and post-survey instrument. Differences in humpback whale distribution and group size patterns were found relative to killer whale occurrence, although humpback whale behavioral states were unchanged. Changes in passenger conservation attitudes could not be attributed to species and behaviors but they were important determinates to whale watching satisfaction. Overall, more positive conservation attitudes and an increase in knowledge about marine mammals were reported after whale watching. These tours provide an opportunity for collecting meaningful scientific data and providing more in-depth education such as enhancing the appreciation for ecosystem services provided by marine mammals.
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Dehalt, Annette Christiane. "Zooplankton resources and humpback whale (Megaptera novaeangliae) feeding ecology in South-East Alaska." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/25866.
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Recent population changes on the SE-Alaska humpback whale (Megaptera novaeangliae) feeding ground may be explained as being primarily due to large-scale oceanographic variations that locally affect plankton productivity. It is suggested that the 1978 whale decline in Glacier Bay was due to localized nutrient limitation caused by climate (El Nino)-induced changes in this fjord's circulatory pattern.
An assessment of zooplanktonic prey in Frederick Sound in summer 1983 was integrated into a long-term monitoring project of the area, and showed generally similar conditions as the previous season. A slight increase in the krill proportion of plankton swarms, small changes in krill species composition, and the occurrence of a Southern-origin copepod species were the notable exceptions. A comparison between zooplanktonic feeding and non-feeding targets suggested euphausiid biomass (mainly Thysanoessa raschii) to be the most likely stimulus for whale feeding activity. Examination of humpback whale fecal material proved a valuable method to identify dietary components.
The local developmental pattern of T. raschii was investigated with regard to its noted importance in humpback whale diet. Dominant life history stages found in 1983 indicated sub-optimal environmental conditions, possibly related to increased coastal warming. Three sub-cohorts were identified in the spring spawning cohort, and developmental timing appeared to be correlated with the whales' migratory pattern.Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate
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Borggaard, Diane L. "Assessing the effects of industrial activity on cetaceans in Trinity Bay, Newfoundland." Connect to this title online, 1996. http://www.nlc-bnc.ca/obj/s4/f2/dsk2/ftp04/mq23120.pdf.
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Mcloughlin, Michael. "The development and application of computational multi-agent models for investigating the cultural transmission and cultural evolution of humpback whale song." Thesis, University of Plymouth, 2018. http://hdl.handle.net/10026.1/11818.
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Three different multi-agent models are presented in this thesis, each with a different goal. The first model investigates the possible role migratory routes may have on song evolution and revolution. The second model investigates what social networks could theoretically facilitate song sharing in a population of whales. The third model implements a formal grammar algorithm in order to investigate how the hierarchal structure of the song may affect song evolution. Finally, the thesis attempts to reconnect the models with their origins and discusses how these models could potentially be adapted for composing music. Through the development of these different models, a number of findings are highlighted. The first model reveals that feeding ground sizes may be key locations where song learning from other population may be facilitated. The second model shows that small world social networks facilitate a high degree of agents converging on a single song, similar to what is observed in wild populations. The final model shows that the ability to recognise hierarchy in a sequence coupled with simple production errors, can lead to songs gradually changing over the course of time, while still retaining their hierarchal structure.
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Drost, Eduard F. "Site Fidelity of southern right (Eubalaena australis) and humpback whales (Megaptera novaeangliae) in Algoa Bay, South Africa." Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/21732.
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The site fidelity of humpback and southern right whales in Algoa Bay was investigated as a baseline study to examine the importance of this area for the future conservation of these species. An absence of whales since the 1980’s from Algoa Bay and more frequent sightings of southern right and humpback whales during a survey conducted between 2008 and 2011 in Algoa Bay led to the present photo-identification study. Data were collected from boat-based surveys along the coastline in 2015 and 2016 and data from a previous boat-based study during 2008-2011 assessing the occurrence of all cetaceans in Algoa Bay were added. A cumulative number of 96 individual southern right whales and 184 individual humpback whales were identified from callosity patterns and dorsal fins, respectively, over this period in Algoa Bay. A low resighting rate for both species was observed within (6.25 for southern right whales & 6.98% for humpback whales) and between years (1.04% for southern right whales & 9.24% for humpback whales) with mainly individual adult humpback whales being resighted. In contrast, all southern right whale resightings were confirmed to be mother-calf pair individuals. The timing of monthly sightings and resightings of mother-calf pair individuals in the bay may suggest that this area may serve as a fairly new nursery area for southern right whales and as a possible migratory corridor for humpback whales during their migrations to and from their breeding grounds. The sighting distribution within the bay suggest that mother-calf pairs are located closer inshore and further away from the shipping activities on the eastern side of the bay in the proximity of two operational ports. This forms an important baseline for future monitoring to assess the effect of increased shipping activity in the bay on the breeding behaviour of the whales. The site fidelity of humpback and southern right whales in Algoa Bay was investigated as a baseline study to examine the importance of this area for the future conservation of these species. An absence of whales since the 1980’s from Algoa Bay and more frequent sightings of southern right and humpback whales during a survey conducted between 2008 and 2011 in Algoa Bay led to the present photo-identification study. Data were collected from boat-based surveys along the coastline in 2015 and 2016 and data from a previous boat-based study during 2008-2011 assessing the occurrence of all cetaceans in Algoa Bay were added. A cumulative number of 96 individual southern right whales and 184 individual humpback whales were identified from callosity patterns and dorsal fins, respectively, over this period in Algoa Bay. A low resighting rate for both species was observed within (6.25 for southern right whales & 6.98% for humpback whales) and between years (1.04% for southern right whales & 9.24% for humpback whales) with mainly individual adult humpback whales being resighted. In contrast, all southern right whale resightings were confirmed to be mother-calf pair individuals. The timing of monthly sightings and resightings of mother-calf pair individuals in the bay may suggest that this area may serve as a fairly new nursery area for southern right whales and as a possible migratory corridor for humpback whales during their migrations to and from their breeding grounds. The sighting distribution within the bay suggest that mother-calf pairs are located closer inshore and further away from the shipping activities on the eastern side of the bay in the proximity of two operational ports. This forms an important baseline for future monitoring to assess the effect of increased shipping activity in the bay on the breeding behaviour of the whales.
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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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Holmes, Davey. "All’s Whale that Ends Whale: How Correctly Identifying Antarctic-Feeding Grounds of Oceania Humpbacks Could Save an Endangered Population." Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/pomona_theses/148.
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Although major whaling practices have ceased, increasing human involvement and influence in the world’s marine ecosystems continue to adversely effect global whale populations. It is a major concern throughout Antarctic waters, where endangered Oceania Humpback Whales (Megaptera novarangliae) annually feed. This study analyzes the extent to which a proposed marine protected area within the Ross Sea may indirectly harm the last remaining endangered population of Humpbacks. Using current satellite tracks of southern Humpback migrations, this model maps the effects of displaced Toothfish fisheries, and suggests further conservations efforts, based on New Zealand’s Precautionary Approach, to protect these vulnerable whales.
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Jones, Meagan E. "Female Humpback Whale (Megaptera novaeangliae) Reproductive Class and Male-Female Interactions during the Breeding Season." Antioch University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1292617002.
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Roberts, Geoff. "Classification of non-stationary signals using time-frequency representations and multiple hypotheses tests : an application to humpback whale songs." Thesis, Queensland University of Technology, 1999.
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Deakos, Mark H. "Humpback Whale (Megaptera novaeangliae) Communication: The Context and Potential Functions of Pec-Slapping Behavior on the Hawaiian Wintering Grounds." Thesis, University of Hawaii at Manoa, 2002. http://hdl.handle.net/10125/7066.
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Humpback whales display a variety of percussive behaviors that may function as communication between conspecifics. Pectoral-fin slapping behavior is commonly observed in a variety of marine mammals including seals, dolphins, and humpback whales. Data from 5-years of behavioral observations of humpback whales on the Hawaiian wintering grounds were compiled and analyzed. Overall findings suggest pec-slapping behavior is dependent on the performer's age class, sex, and social role. Adult females appear to pec-slap in competition groups in efforts to encourage competition from surrounding males, indicating her readiness to mate. Adult males pec-slap while disaffiliating from other males, possibly in attempts to maintain a non-agonistic male association. Subadult pee slapping is likely a form of "play", an important characteristic in the development, coordination, and learning in young mammals. These discoveries can serve as tools to enhance the interpretation of humpback whale social behavior, and provide a model for understanding other percussive behaviors.xvii, 148 leaves
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Dalle, Luche Greta. "Validation and use of a HPLC-MS/MS method for the analysis of multiple steroid hormones in humpback whale blubber." Thesis, Griffith University, 2020. http://hdl.handle.net/10072/392397.
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This thesis describes the novel use of multiple steroid hormone analysis to investigate and gain understanding of previously unknown aspects of the endocrinology and reproductive biology of the Southern Hemisphere humpback whale (Megaptera novaeangliae). Steroid hormones are a class of structurally related molecules that function as messengers in a variety of important physiological processes (e.g. salt homeostasis, immune system, sexual development and reproductive cycles). A number of endogenous steroid hormones have been identified as critical for reproduction (e.g. androgens, progestogens, oestrogens) and stress response (e.g. corticosteroids) in mammals. Understanding the species-specific roles and baseline levels of endogenous steroid hormones enable these compounds to be used as biomarkers of reproductive status and stress exposure. The use of steroid biomarkers for these purposes promises to be extremely advantageous in cetacean species, since other approaches often require increased time and resources. However, the collection and interpretation of steroid hormone data in the humpback whale is currently limited by methodological issues (e.g. challenging sampling, difficult comparison between sample types, analytical approach restricted to single hormone analysis), and by a general lack of detailed knowledge of the humpback whale endocrine system.
Collection of biological samples from cetaceans is inherently difficult. In particular, free-swimming individuals of baleen whale species, including humpback whales, cannot be kept in captivity, nor they can be immobilised for sampling. Contemporary studies have demonstrated that steroid hormones analysis is viable in baleen species through the use of remotely collected tissues and fluids (i.e. faeces, blow, blubber). The seasonal migration of the humpback whales from the Antarctic feeding areas to the tropical breeding grounds, however, imposes further restrictions in regard to sample types and timing of collection. To date, blubber is the only matrix employed for steroid analysis in this specie and comprehensive seasonal steroid hormone changes have not being studied.
Blubber is a lipid-rich tissue, able to sequester traces of steroid hormones from circulation. This is advantageous as multiple types of steroid hormones are likely to be present in this tissue. However, steroid hormones in blubber, particularly those at trace levels, can only be quantified by using sensitive techniques that need to accommodate the presence of lipids in the matrix. Enzyme immunoassay (EIA) is typically used for steroid hormone analysis in complex matrices, as it requires minimal sample preparation. Although EIA provides high sensitivity, its precision can suffer due to the indirect nature of the measurements and by the possibility of cross-reactivity. A significant disadvantage of employing EIAs for the investigation of species-specific endocrinology is that each EIA quantifies only a single steroid hormone, or a single class of steroid metabolites in its ensemble. Single steroid hormone measurements can be misleading, as steroid hormones act in concert. The same steroid hormone can have different roles and increase or decrease in concentration to accommodate different biosynthetic pathways (e.g. acting as an active metabolite, or as a precursor to or degradation product from other steroids). Liquid chromatography coupled with tandem mass-spectrometry (LC-MS/MS) represents an alternative to EIAs, as it can provide accurate and precise quantification of multiple steroid hormones from the same sample portion. Major issues in LC-MS/MS methods include the coelution of multiple analytes or the interference of matrix components, which can sometimes be resolved only through a trade-off between analyte resolution and sensitivity. These challenges can however be identified prior to the analysis, and overcome, at least partially, by optimising the sample extraction and cleanup. This thesis aimed to adapt and validate a LC-MS/MS method for extracts of humpback whale blubber, and to evaluate use of multiple steroid hormone measurements in relation to reproductive status and possible stress exposure from free-ranging individuals.
Blubber samples from stranded humpback whale carcasses were initially employed to assess the applicability, scope, and repeatability of a LC-MS/MS method for the analysis of multiple steroid hormones (Chapter 2). The method, initially developed for bottlenose dolphin (Tursiops truncatus) blubber, proved to be applicable to the comparatively lipid-rich humpback whale outer blubber. Levels of five corticosteroids and six reproductive steroids (including androgens, progestagens and oestrogens) were determined in humpback whale blubber, and ten of these analytes could be quantified with high accuracy (error on amended samples < 15%) and repeatability (percent standard deviation < 15%). The multi-steroid hormone profiles obtained by the stranded carcasses were also investigated as potentially indicative of the endocrinological responses of some of the whales to stress exposure. Subsequently, the LC-MS/MS method was applied to biopsy extracts from freeswimming humpback whales collected at two time points of the whale breeding season over multiple years. The application of this methodology to live biopsies resulted in a smaller number of analytes detected, predominantly as an effect of the corticosteroid analytes being lower in concentration or undetectable in these samples. The quantified steroid hormones provided, however, novel insights into endocrinology and reproductive biology of female (Chapter 3) and male (Chapter 4) humpback whales.
In Chapter 3, we show how the use of a previously validated pregnancy concentration threshold for the single hormone progesterone failed to detect any pregnant females based on LC-MS/MS analysis of blubber extracts from 23 females sampled while approaching the breeding grounds. However, by considering multiple steroid profiles including androgens and cortisol, we suggest that relatively high blubber concentrations of androstenedione may distinguish pregnant individuals during the last month of gestation. This hypothesis is supported by reference to steroid hormone measurements through pregnancy in evolutionarily related mammal species, although further work (e.g combining photo identification) is required to provide conclusive evidence. In addition, the same previously validated progesterone threshold resulted in an unexpectedly low proportion of pregnant females (3%) from among 29 females departing the breeding grounds. This prompted the suggestion of a new lower progesterone concentration threshold for assignment of early pregnancy status.
In Chapter 4, the seasonal variations in blubber steroid hormone concentration in males are examined through the breeding season. Lowering of testosterone during the expected peak in reproductive activity suggests asynchronicity between blubber testosterone levels and male fertility. Correlation analyses among multiple hormone couples are used to postulate the changes in biosynthetic pathways behind the large interseasonal variations in steroid concentrations. These large intra-season variations in blubber androgens and a contrasting relationship with cortisol across the migration, encourages further investigation on the effects of age and sexual maturity on concentrations of these two hormones. This is necessary before they can be used as biomarkers for reproductive status or stress exposure.
An application of how some of the multi-hormone information can be used to improve humpback whale monitoring is provided in Chapter 5. Early and late pregnancy diagnoses as formulated in Chapter 3, are combined with body condition information simultaneously measured in the same female individuals. Superior body condition among late-pregnant female corroborated previous observations that females would increase their feeding opportunities before parturition in order to support, as capital breeders, the combined energetic cost of migration and lactation. In contrast, no relationship was found between whales identified as early pregnant and their body condition compared to the rest of the migrating females. These results suggest that body condition and fertility might not be directly related during the breeding season. Instead, annual winter-feeding efficiency might be more important than accumulated energy stores in guaranteeing the annual reproductive success in females of this species.
Overall, by analysing for a larger suite of steroid compounds and focusing on a comparatively less studied period of the migration, this work revealed some limitations of the current methodology used to measure steroid hormones in humpback whales. These findings enhance our knowledge of the humpback whale endocrine system and provide new approaches for the diagnostic use of steroid hormones profiles in free-swimming humpback whales.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Rambeau, Andrea Louise. "Determining abundance and stock structure for a widespread migratory animal : the case of humpback whales (Megaptera novaeangliae) in British Columbia, Canada." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2819.
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Developing appropriate management plans for species at risk requires information about their population structure and abundance. For most cetacean populations, few reliable population estimates are available and even fewer distributions have been mapped. Accurate abundance estimates can be determined from capture-recapture data if assumptions are met, however this can be difficult when the animal in question demonstrates both strong site fidelity and large-scale migrations, and different models can result in dramatically different results.
I explored these issues by examining a 15-year dataset (1992-2006) of photo-identifications of humpback whales (Megaptera novaeangliae) in British Columbia (BC), Canada. I used multiple capture-recapture models to compare how the definition of population and variation in effort affected estimates of population size, and I explored means to correct for these biases. I also considered stock structure by examining individual breeding ground destinations, movement, and localized site-fidelity within BC.
Across the six models considered, the BC humpback whale abundance in 2006 ranged between 1,428 and 3,856 individuals. The Lincoln-Petersen estimate (1,428-1,892) likely best described the number of humpback whales in BC during summer 2006. The effort-standardized Jolly-Seber model (1,970-2,331) is more representative of the larger population of humpback whales that uses or passes through BC over multiple years. Ultimately, selecting the best estimation model requires defining the ‘population’ of interest and accounting for spatial and temporal distribution of sampling effort.
British Columbia provides feeding habitat and a potential migratory corridor for whales that breed in the northeastern Pacific Ocean. Forty-four percent of the 1,986 humpback whales considered were sighted in BC in more than one year. Identifications were highest from May to October, with a peak in September, but humpback whales were present in BC in all months of the year. Whales showed strong site fidelity with a median re-sighting distance of 75 km between years, and a maximum re-sighting distance that ranged from 0.41 km to 842 km. Matching rate within BC decreased as a function of north-south distance, though no clear north-south boundary could be established. Stock structure of humpback whales in British Columbia is complex and should be considered in managing this population.
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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.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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Fojtíková, Marcela. "Návrh rychloběžné vodní turbíny s tvarovanou náběžnou hranou lopatky oběžného kola." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230899.
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This master thesis is devoded to examination of influence of bumped leading edge of hydraulic turbines ruber blade to characteristics of blade cascade. Thesis is based on hydraulic turbine which countoured/bumped leading edge of blade was created using previous studies on NACA profiles. The main goal of this thesis is to Compare shaped leading edge with flat leading edge using CFD calculations. Programms like SolidWorks and Gambit were used to calculate geometrics and meshes.
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Suzacq, LucÃa de la Paz. "Changes in abundance and distribution of humpback whales Megaptera novaeangliae in Hervey Bay Marine Park, Australia, based on aerial surveys conducted in 1992 and 2004." Scholar Commons, 2007. http://scholarcommons.usf.edu/etd/2380.
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Aerial surveys were conducted throughout Hervey Bay Marine Park between August and October 1992 and 2004 to determine changes in abundance and distribution of the Eastern Australia humpback whale population in this area. Due to concerns about possible effects of boat traffic on whale distributions associated with a growing whale watching industry, the number and location of vessels were also recorded during these surveys. Throughout the 1992 season, 17 flights were conducted and a total of 41.93 surveys hours were completed, recording 186 pods, and a total of 320 animals. In addition, 392 boats were spotted in the area. During 2004, 10 flights took place with a total of 23.56 survey hours, 203 pods were sighted and a total 388 animals were recorded. In addition 216 boats were spotted in the study area.Results suggested an overall increase in the density of whale sightings from 1992 to 2004. By comparing total numbers for both years normalized to the number of survey hours, it can be seen that the total number of pods and the total number of individuals both increased. In 1992, with 7 more flights and an extra 10 hours on survey, the total number of pods and the total number of whales observed were less than in 2004. The composition of the pods showed a variation throughout both seasons consistent with a known distinctive temporal segregation of humpback whales on their annual migration. The percentage of calves was higher in 2004 than in 1992 consistent with the overall recovery of the eastern Australia population.Boat traffic did not show an effect on whale distributions in either year of the study. However this work provides a baseline for continuing to monitor boat traffic and whale distributions to help ensure that the east Australia whale population will continue to recover together with a sustainable growing whale watching industry.
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Cartwright, Rachel. "A comparative study of the behaviour and dynamics of humpback whale (Megaptera novaeangliae) mother and calf pairs during their residence in nursery waters." Thesis, Manchester Metropolitan University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409502.
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This study provides quantitative data on the variation in behaviour of humpback whale (Megaptera novaeangliae) mother and calf pairs during their residence in two known nursery regions; the westerly, leeward regions of the islands of Maui and the Big Island, Hawaii. Data were collected over a five year period from 1999 to 2003 and exclusively within waters of less than 100 fathoms. The initial investigation aimed to determine any age-related changes in calf behaviour. The exact age of calves seen in nursery waters is unknown, however, calves with distinctly furled dorsal fins are seen and flaccid or furled fins are a commonly reported feature for very young neonates of other cetacean species. Such furled fins reportedly unfurl over time and results in this study indicated a significant relationship between the relative unfurling of the calf's dorsal fin and increases in the calf's maximum dive times, a known physiological attribute in neonate cetaceans that increases with age. The degree of furl of the dorsal fin was therefore applied as a morphological indicator of the relative age of the calf. Adequate photographic documentation of the dorsal fin and extended behavioural data, obtained during extended focal follows, were compiled for 69 calves and these were classified into two discrete relative age classes, separated by a midrange buffer group. Two distinct age-related behavioural regimes were identified; in younger calves the predominant behaviour was persistent travel, accounting for 85 (62-97)% of the calf's time budget, within the older age group time spent travelling dropped to 47 (26-68)% of the time budget and median time spent stalled underwater increased by 31%. Frequency of some specific surface behaviours, such as tail slaps and tail swishes, changed slightly with the calf's relative age, whereas other behaviours were consistently seen in calves in both relative age classes, e.g. twirling. The calf's breathing regime also varied between age classes: mean extended dives lengthened with age, increasing from 120 (s.d. 49) seconds for young calves, to 175 (s.d.55) seconds for older calves and the frequency of intermittent blows, between 30 and 60 seconds, fell from 22 (s.d. 13) to 12 (s.d. 8) per hour as the calf matured. A range of interactions between the behaviour of the calf and the calf's breathing regime were also documented. Variation in mother and calf behaviour between different nursery regions was limited to changes in the orientation of the mother and calf pair; this may indicate an adaptive response to increased levels of vessel traffic in favoured nursery areas. Within specific nursery regions interplay between habitat and behaviour was evident; in the four island area mother and calf pairs with older calves that were travelling were found closer to shore than those with older, resting calves and on the Big Island stratification by water depth, according to group composition was documented. A summary of incidents of calf injuries and mortalities during this period was compiled and these provide valuable insight into factors that may impact calf behaviour and patterns of habitat utilisation in this region. Finally a series of management recommendations are provided that take into account the changes in behaviour of calves during the nursery period and across the nursery region.
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Doniol-Valcroze, Thomas. "Spatial distribution of rorqual whales in the Strait of Jacques Cartier, Gulf of St. Lawrence, Quebec, Canada." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33749.
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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.
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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.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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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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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.
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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’espèceOf 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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Fassmann, Wesley N. "An Experimental Study of Bio-Inspired Force Generation by Unsteady Flow Features." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/5316.
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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.
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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.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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Dalla, Rosa Luciano. "Modeling the foraging habitat of humpback whales." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/23486.
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Knowing how species will respond to environmental variability and climate change requires understanding the factors that influence their distribution and movement patterns. I investigated the processes that drive individuals to concentrate in specific areas of their home range by modeling encounter rates of humpback whales (Megaptera novaeangliae) in relation to environmental variables using GIS tools, generalized additive models, and remote sensing and in situ data. I conducted this work at two foraging areas: the coastal waters of British Columbia, Canada, and the Bransfield and Gerlache Straits, Antarctica.
Humpback whales in British Columbia were strongly associated with latitude and bathymetric features. The relationships with remotely sensed variables reflecting primary productivity were not consistent, but higher numbers of whales seemed to be associated with higher productivity. In fact, the highest concentrations of humpback whales appeared to reflect areas where concentration and retention processes lead to higher biological productivity, including south Dixon Entrance, middle and southwestern Hecate Strait and off Juan de Fuca Strait.
Humpback whales in the Southern Ocean also preferred areas of enhanced biological productivity. In Gerlache Strait, humpback whales were associated with areas of higher chlorophyll-a concentration in the central and northern sections of the strait, which also corresponded to relatively higher temperatures and shallower mixed layer depths for the in situ data. In Bransfield Strait, humpback whales appeared to prefer the near-frontal zones and the deep basins, where surface waters are influenced by the Bransfield Current. Interannual variability in both humpback and minke whale encounter rates in Gerlache Strait was correlated with the Oceanic Niño Index, the oceanic component of ENSO.
In addition to investigating species-habitat relationships with statistical models, I conducted the first study to describe the satellite-monitored movements of humpback whales on their feeding grounds along the Antarctic Peninsula. Results showed considerable individual variation in direction, speed and range of movements, and an overall pattern characterized by short- and long-distance movements between presumed foraging areas with relatively short residency times.
All told, the results of my research show that humpback whale distribution within foraging habitat is influenced by physical and biological variables that enhance biological productivity.
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Clapham, Phillip J. "Social and reproductive biology of North Atlantic humpback whales (Megaptera novaeangliae)." Thesis, University of Aberdeen, 1993. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU552767.
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The social and reproductive biology of individually identified humpback whales, Megaptera novaeangliae , was studied in the Gulf of Maine (a summer feeding ground), and in Samana Bay, Dominican Republic (a winter mating and calving area). In the Gulf of Maine, humpback whales showed high rates of seasonal occurrence and annual return, strongly suggesting that this species exhibits foraging area philopatry. The mean crude birth rate was 0.083; an alternative measured was 0.42 calves per mature female per year. Eighty-four of 96 unbroken calving intervals were of two or three years (mean &'61 2.3 years). Separation between mother and calf occurred after one year in 96&'37 of cases. Resightings of independent calves indicate that the composition of feeding stocks is determined matrilineally. The mean age at sexual maturity (determined from observations of calves born to 12 females of known age) was five years; observations from Samana Bay suggest that males attain maturity at this age also. The sex ratio of the offspring of female humpback whales in superior condition (inferred from calving interval) was biased towards sons (the sex with the greater variance in reproductive success). Social organization was characterized by small, unstable groups, with stable associations and associations between relatives being rare, territoriality and dominance were apparently absent. Immature whales become socially adult at sexual maturity. In Samana Bay, molecular analysis revealed that no competitive group contained more than one female, although several consisted entirely of males, perhaps reflecting dominance sorting. Observations of aggressive females may represent repulsion of subadult males. Males may occasionally form coalitions. The occurrence of whales from different high-latitude feeding grounds in these groups suggests that the North Atlantic population is panmictic.
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Castrillon, Posada Juliana. "Development of Non-lethal Methods for the Evaluation of Energetic Reserves in Humpback Whales (Megaptera novaeangliae)." Thesis, Griffith University, 2019. http://hdl.handle.net/10072/386540.
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Cetaceans have been suggested as ideal ocean sentinels for the evaluation of ecosystem health because they are long-lived, higher trophic foragers, often with high site-fidelity. The body condition of cetaceans provides an integrated picture of foraging success and energy expenditure and thus represents an effective ‘sentinel parameter’ for ecosystem monitoring. In addition, the body condition of an individual can serve as a predictor of reproductive success and offspring survival. The ability to monitor the body condition of cetaceans is therefore of direct relevance for conservation biology. Despite the value of this parameter, there is currently a lack of reliable, standardized, non-lethal methodologies for its evaluation across species and age-categories.
The introduction chapter describes the natural history of the humpback whale (Megaptera novaeangliae) in the context of its Antarctic ecosystem and its energetic requirements. It sets out that the species is among the most vulnerable in a changing environment due to it being a specialised feeder depending on Antarctic krill. Krill is the keystone of the Antarctic ecosystem and is presently facing numerous threats. Humpback whales are capital breeders that spend summers feeding in high latitude feeding grounds, building up their energy reserves reflected in their body condition. During winter they migrate to tropical waters to reproduce, a journey that is fuelled by the energy stores previously accumulated. The seasonal dynamics of intensive feeding and lipid deposition, followed by high energy activities that are accompanied by fasting and lipid mobilisation, render the species ideal for the study of possible biomarkers of fluctuating energy stores. This thesis focuses on the evaluation of fluctuating adiposity of southern hemisphere humpback whales.
The second chapter presents a critical review of the available approaches of assessing cetacean body condition. Currently the methodologies can be divided into four groups, namely: Blubber Measures, Body Composition, Body Morphometry, and Biochemical and Chemical Biomarkers. The last category is dedicated mainly to new developments and explores the emerging methodologies. This chapter describes and analyzes their applications as well as their respective strengths and weaknesses. The chapter concludes by advocating research priorities that fill the critical technical research needs for a reliable, non-lethal and standardized methodology that is applicable across species and age-categories and for large numbers of individuals.
In response to the research need identified in chapter two, chapter three investigates adipocyte metrics as a potential biomarker of adiposity in humpback whales. Blubber is composed of adipocytes, which are filled with lipids according to the individual energy reserves. This means that a change in total energy reserve impacts the volume of individual adipocytes. Two adipocyte metrics were assessed histologically: the two-dimensional adipocytes area and the relative proportion of adipocyte space in the blubber tissue which is termed the adipocyte index. Both adipocyte metrics exceed the sensitivity of the most widely used proxy for energetic reserves, blubber lipid percentage, thus validating the implementation of adipocyte area and the adipocyte index as energetic reserve biomarkers. This published work therefore advocates the inclusion of these measures, obtained from superficial blubber biopsies, in long-term monitoring programs as a means of improving evaluation of fluctuating energy reserves.
Following the molecular techniques’ potential to assessing body condition identified in the second chapter, chapter four explores the RNA extraction from humpback whale blubber for downstream applications. Good quality RNA is a prerequisite for successful downstream applications, however its extraction can be difficult, especially if the starting material is high in lipids. This chapter describes the strategic approach taken for method optimization and the difficulties encountered.
The fifth chapter provides a theoretical basis for the use of blubber proteins “adipokines” as biomarkers of adiposity. The main physiological role of blubber is energy storage; however, the tissue is highly integrated into the overall physiological and metabolic control systems of mammals. This mechanism is carried out through the secretion of proteins, synthesized in the adipose tissue and actively involved in the lipid dynamics, with a profound effect on food intake and energy expenditure in model species. The different concentrations of these proteins, such as leptin and adiponectin inform the hypothalamus of the amount of energy stored. However, very little is known about the operation of adipokines in animals that experience extreme fluctuations in their energy reserves while at the same time using adipose tissue as insulation as cetaceans do. This chapter explores the possibility that the gene expression profile of selected adipokines may provide insight into the fluctuating energetic health of cetaceans. This chapter also outlines trialled approaches and advocates future priorities.
The key findings and implications of this work are discussed in the concluding chapter. In summary, this study makes clear the importance of the energy reserves measurement and its ecological scope. It identifies the priorities for the improvement and standardization of the current methodologies and highlights the importance of new developments, pointing towards possible areas for further development. It proposes a simple and easily applicable methodology that improves precision and accuracy of the current method. In addition, it proposes advances in the optimization of the extraction of good quality RNA from blubber for downstream application. Finally, it explores the gene profile of the adipokines leptin and adiponectin, leaving the theoretical bases and some progress in the study of adipokines gene expression from humpback whale blubber.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Eisenmann, Pascale. "Interpreting the Feeding Ecology of Southern Hemisphere Humpback Whales through Biochemical Assessment." Thesis, Griffith University, 2016. http://hdl.handle.net/10072/365650.
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Southern hemisphere humpback whales are high-fidelity krill predators relying on high Antarctic krill biomass to survive and undergo successful reproduction. During the austral summer, humpback whales consume large quantities of krill and build up their blubber reserves. The rest of the year is spent migrating to temperate waters and back while relying on accumulated energy reserves. This expected reliance on Antarctic krill underpins our understanding of Southern hemisphere humpback populations. Their Northern hemisphere counterparts are however known to be more flexible in their feeding habits, and recent work has shown that the Southern hemisphere populations are capable of a certain feeding plasticity, with multiple visual reports of supplementary feeding during the migration, and evidence of anomalous feeding observed in baleen plates. Due to the dependency of Antarctic krill on sea-ice duration and extent for its larval recruitment, the entire Antarctic sea-ice ecosystem is expected to destabilise in a changing climate. The resulting effects on high-fidelity krill predators, such as humpback whales, are unknown. Detailed, long-term information regarding current and past diet, migration and metabolism of humpback whales are needed to successfully assess possible trophodynamic variability, and to differentiate between the natural feeding plasticity of this species and population responses to climate driven environmental change. This thesis aims to evaluate whether Australian humpback whale populations display feeding plasticity in their prey choice and/ or feeding locations.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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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 SudUnderstanding 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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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: 2012-08-07Conselho 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
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Minton, Alma Gianna. "Ecology and conservation of cetaceans in Oman with particular reference to humpback whales." Thesis, University of London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413422.
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Müller, Andrea. "Humpback whales, rock lobsters and mathematics : exploration of assessment models incorporating stock-structure." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/11342.
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This thesis presents four marine resource assessments; three concern the Southern Hemisphere (SH) humpback whale (Megaptera novaeangliae) and one the South African east coast rock lobster Palinurus delagoae. It also sets out the statistical background to the methodology employed in the assessments, including an outline of the Bayesian approach, Bayes' theorem, and the sampling-importance re-sampling (SIR) as well as the Markov Chain Monte Carlo (MCMC) methods.
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Witteveen, Briana. "Using Stable Isotopes to Assess Population Structure and Feeding Ecology of North Pacific Humpback Whales (Megaptera Novaeangliae)." Doctoral diss., University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3979.
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The North Pacific humpback whale (Megaptera novaeangliae) is a wide-ranging baleen whale species with a complex life history and population structure. As seasonal migrants, humpback whales are known to inhabit cooler, high-latitude waters when foraging and low-latitudes for mating and calving. Beyond this general migratory pattern, a number of demographic characteristics including, abundance, distribution, seasonal occurrence, and prey preferences remain unknown or poorly described. A complete understanding of humpback whale ecology is therefore lacking. Many methods used to explore these aspects of cetacean ecology are either prohibitively expensive or limited in the scope of what can be learned from their use. Fortunately, in recent years, the analysis of stable isotope ratios of animal tissues has proved a valuable and relatively inexpensive technique for providing information on trophic position, diet, and feeding origins of migratory populations. This study employed techniques in stable isotope ecology to increase knowledge of the population structure, migration routes, and foraging ecology of North Pacific humpback whales. Skin samples were collected from free-ranging humpback whales throughout all known feeding and breeding grounds and were analyzed for stable carbon ([delta]13C) and nitrogen ([delta]15N) isotope ratios. The population structure of humpback whales was first explored through geographic differences in stable isotope ratios. Stable isotope ratios varied significantly with location of sample collection. Based on this analysis, foraging animals were separated into six feeding groups. Classification tree analysis was then used to determine which isotopic variables could be used to predict group membership. Probable migratory linkages were then described by applying results of classification trees to [delta]13C and [delta]15N of animals sampled on breeding grounds. Strong migratory connections between the eastern-most foraging and breeding areas and the western-most areas were reflected in similarities of stable isotope ratios. Foraging ecology was then examined through calculation and comparison of the relative trophic levels of the six feeding groups. Isotopic values suggest some feeding groups are piscivorous, while others feed on a more mixed diet. These results can be used to determine if differences in diet composition between groups result in differences in accrued nutritional benefits, negatively impacting reproductive success and survival relative to fish eating groups. Finally, to gain insight into specific foraging habits, the diet of one group of humpback whales was modeled using an isotope mixing model. The [delta]13C and [delta]15N of Kodiak Island, Alaska humpback whales and several species of potential prey indicate that these animals likely rely heavily on euphausiids (Thysanoessa spinifera), Pacific sandlance (Ammodytes hexapterus), and capelin (Mallotus villosus). This study represents the first application of stable isotope ecology to an entire population of marine mammals. Stable isotope analysis was successfully applied to describe and improve understanding of the demographics of North Pacific humpback whales.Ph.D.
Department of Biology
Sciences
Conservation Biology PhD
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Barendse, Jaco. "Local movements, migrations and habitat use of humpback whales off the west coast of South Africa, including observations of southern right whales." Thesis, University of Pretoria, 2012. http://hdl.handle.net/2263/30845.
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The migration of Southern Hemisphere humpback whales Megaptera novaeangliae between their
feeding and breeding areas is considered a highly predictable and seasonal event. The west coast of
Africa is host to Breeding Stock (BS) B, which has been divided into sub-stocks B1 and B2 based on
different catch histories observed between Gabon in the north, and other stations to the south – a
notion supported by recent regional genetic analysis, some samples of which were collected during
this project. It has thus been assumed that the west coast of South Africa (WSA) functions as a
migratory corridor for BS B2 whales. While catch data from Saldanha Bay in 1911-12 supported the
existence of two migration peaks, a pilot study in the spring of 1993 (the first dedicated study in over
80 years) suggested a more atypical pattern, with some whales apparently abandoning or suspending
their migration, possibly to feed. This has been complicated further by the detection of direct transits of
10 individual humpbacks through microsatellite matches between Gabon and WSA, and has raised
questions about the exact function and relationship of WSA to BS B humpback whales.
This thesis presents the results from a study based at Saldanha Bay that included shore-based
observations of whale groups during two field seasons (July – December 2001, May 2002 - February
2003), and photographic and genetic data collected during boat intercepts from 1983 to 2008. The
observed relative abundance of humpback whales again did not support a classical migration pattern,
with the highest sighting rates from mid-spring through summer. Movement patterns of humpback
groups tracked by theodolite showed mid-spring to be a turning point in their behaviour, after which
they swam significantly slower, showed an increase in ‘non-directional’ movement, and were found
farther from shore. Data on group composition and sex showed a significantly female-biased sex ratio
during mid-spring, unlike most low-latitude areas where males predominate. The individual
identification of humpback whales by means of photographs of ventral tail flukes, left and right dorsal
fins, and through microsatellites, yielded numerous resightings at intervals of a year or more,
indicating a high level of fidelity to the region and temporary residency by some individuals. Population
estimates were calculated using open and closed capture-recapture models and suggest that about
500 animals are present in the area during the spring/summer season.
Direct observation of humpback whales feeding on crustacean prey, short-term association patterns,
and the resighting of individuals participating in feeding aggregations in multiple years confirmed this
area to be a feeding ground for humpback whales during spring and summer months. Concurrent
shore-based observations on southern right whales Eubalaena australis showed that this species was
present virtually throughout the study period, also utilising feeding opportunities during summer. The
potential benefit of this mid-latitude feeding area for humpback females is illustrated by a record of a
cow that produced calves in three consecutive years, each of which survived to at least six months of
age - the first observation of post-partum ovulation for this species in the Southern Hemisphere. The
return of three known calves to the same area is strongly suggestive of maternally derived site fidelity.Thesis (PhD)--University of Pretoria, 2012.
Zoology and Entomology
PhD
Unrestricted
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Casa, Maria V. "Accumulation of Emerging Chemicals in Southern Hemisphere Humpback Whales (Megaptera novaeangliae) and Species-specific Chemical Effect Assessment." Thesis, Griffith University, 2022. http://hdl.handle.net/10072/411890.
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Millions of hazardous chemicals are synthesized each year. Their release often represents a risk for the environment and biota. As part of a broader effort to investigate the accumulation and effect of emerging chemicals of concern in the Antarctic sea-ice ecosystem, this thesis focuses upon exposure and effect assessment in southern hemisphere (SH) humpback whales (Megaptera novaeangliae). Cetaceans traditionally represent ideal targets for exposure assessment to Persistent Organic Pollutants (POPs), that is chemicals identified as persistent, bioaccumulative, toxic and capable of long-range environmental transport. Their extended life span and high proportion of body fat render cetaceans susceptible to accumulation of elevated burdens. Southern hemisphere humpback whales feed almost exclusively on Antarctic krill (Euphasia superba) and thus represent second order consumers of the Antarctic sea-ice ecosystem. Exposure assessment consisted of targeted analysis of short-chain chlorinated paraffins (SCCPs) included under the Stockholm Convention (SC) in 2017, and brominated structures listed in 2009 as well as novel, naturally occurring brominated structures, already detected at lower trophic levels of the Antarctic sea-ice ecosystem. SCCPs were targeted in stranded specimens and were detected in 77.7 % of samples, representing the first detection of SCCPs in any mysticetes or any Antarctic foraging marine mammal.Blubber samples from free-swimming and stranded specimens were dedicated to the analysis of the modern category of POPs, polybromodiphenilethers (PBDEs), and a naturally occurring brominated compound, 2,4,6-tribromoanysole (TBA), the chemical structure of which closely resembles PBDEs, flagging the possibility of similar toxic action. Humpback whale PBDEs profiles were dominated by tetra- and penta- congeners, supporting a single previous study on PBDE accumulation in Southern hemisphere humpback whales feeding in the Antarctic Peninsula region. Further, the detection of decaBDE adds support for the local emissions or particle bound transport to Antarctica. PBDE congeners were detected in all samples analysed, whilst TBA was 88 detected in 80% of samples. Upon establishing accumulation of three novel chemical groups in the Antarctic sea-ice ecosystem, species-specific effect assessment was performed through cytotoxicity assessment implementing the newly established immortalized humpback whale fibroblast cell line (HuWaTERT). Two endpoints were targeted, namely membrane integrity and metabolic activity following 24h exposure to an SCCP cocktail, BDE-47, BDE-99, TBA. Each assay also incorporated the assay reference chemical, p,p’-DDE. The four chemicals did not show a dose-dependent response comparable to the one produced by the reference chemical. Whilst p,p’-DDE induced a decrease of both metabolic activity and membrane integrity, the cell response to BDE-99 indicated a positive, or potentially hermetic relationship with regards to the metabolic activity, warranting further investigation of underlying mechanisms.The final thesis chapter explores the unique potential of HuWaTERT for the generation of induced pluripotent stem cells (iPSCs). The main objective of this work was to generate a source of a number of different cell lines from the iPSCs, that could be applied for a more tailored approach to in-vitro chemical effect evaluation to fill the gap currently existing in the field of cetacean toxicology. The re-generation trial involved the use of the Sendai virus, which induces the de-differentiation mechanism in HuWaTERT to become iPSCs without integrating into the cell genome. After successfully generating a number of iPC colonies, the cells ultimately did not thrive, likely due to a fungal infection. Overall, this thesis combines both chemical exposure and effect assessment of novel chemical groups, for unique insight into chemical accumulation and impact in the Antarctic sea-ice ecosystem. The work provides new information regarding the range of chemicals that Antarctic consumers are exposed to, a reflection of hemispheric chemical usage and local input, and also contributes invaluable species-specific in vitro toxicity assessment data, which represents a critical research gap for cetacean chemical impact assessment.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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