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1
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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Moore, Sue E. "Cetacean habitats in the Alaskan Arctic /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1997. http://wwwlib.umi.com/cr/ucsd/fullcit?p9823707.
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Zerbini, Alexandre N. "Improving precision in multiple covariate distance sampling : a case study with whales in Alaska /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/5391.
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Lambert, Olivier. "Long-snouted dolphins and beaked whales from the Neogene of the Antwerp area: systematics, phylogeny, palaeoecology and palaeobiogeography =." Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211020.
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This work is mainly based on the collection of Neogene (Miocene-Pliocene) odontocetes (toothed whales) from the area of Antwerp (northern Belgium, southern margin of the North Sea Basin) preserved at the Institut royal des Sciences naturelles de Belgique (IRSNB). <p> The systematic revision of members of the long-snouted dolphin family Eurhinodelphinidae leads to the description/re-description of five species in the genera Eurhinodelphis (E. cocheteuxi and E. longirostris), Schizodelphis (S. morckhoviensis), and Xiphiacetus n. gen. (X. cristatus and X. bossi). Furthermore, the systematic status of several eurhinodelphinid species from other localities in the world is revised. A cladistic analysis with the parsimony criterion is undertaken to highlight the phylogenetic relationships of several eurhinodelphinid taxa with other fossil and extant odontocetes. Eurhinodelphinids are more closely related to the beaked whales; the latter are distinctly separated from the sperm whales. A second analysis, with a likelihood criterion, reaches nearly identical results. Then a separate parsimony analysis investigates the relationships within the family Eurhinodelphinidae; the results suggest sister-group relationships between Schizodelphis + Xiphiacetus and Ziphiodelphis + (Mycteriacetus + Argyrocetus) and a more stemward position for Eurhinodelphis. After that, anatomical, palaeogeographic, and phylogenetic data allow several suggestions about the ecological features of the eurhinodelphinids. The extinction of this family, before the end of the Miocene, is commented, related to the changes in the biodiversity of other odontocete groups and to a contemporary major sea level drop. <p>\<br>Doctorat en sciences, Spécialisation biologie animale<br>info:eu-repo/semantics/nonPublished
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MacLeod, Colin D. "Niche partitioning, distribution and competition in North Atlantic beaked whales." Thesis, Aberdeen : University of Aberdeen, 2005. http://www.marineconnection.org/docs/MacLeod_PhD_Thesis.pdf.
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Isojunno, Saana. "Influence of natural factors and anthropogenic stressors on sperm whale foraging effort and success at high latitudes." Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/6760.
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Behavioural responses can reveal important fitness trade-offs and ecological traps in evolutionarily novel contexts created by anthropogenic stimuli, and are of increasing conservation concern due to possible links to population-level impacts. This thesis illustrates the use of proxies for energy acquisition and expenditure within multivariate and state-based modelling approaches to quantify the relative time and energetic costs of behavioural disturbance for a deep-diving marine mammal (Physeter macrocephalus) in foraging grounds in Kaikoura Canyon (New Zealand) and near Lofoten Islands (Norway). A conceptual framework is first developed to identify and explore links between individual motivation, condition and external constraints to behavioural disturbance [Chapter 1]. The following chapters then use data from behavioural response studies (BRS) to: 1) derive biologically relevant metrics of behaviour [all chapters], 2) investigate effects of boat-based focal follows and tagging procedures [Chapters 2-3], and 3) relate responses to specific disturbance stimuli (distance, approach, noise) from whale-watching [Chapter 2], naval sonar and playback of presumed natural predator (killer whale Orcinus orca) sounds [Chapter 4]. A novel hidden state model was developed to estimate behavioural budgets of tagged sperm whales from multiple streams of biologging (DTAG) data [Chapter 3]. Sperm whales traded off time spent at foraging depths in a non-foraging and non-resting state in response to both tag boat presence, 1-2 kHz naval sonar (SPL 131-165 rms re 1μPa) and mammal-eating killer whale sound playbacks, indicating that parallel non-lethal costs were incurred in both anthropogenic disturbance and presumed antipredatory contexts. While behavioural responses were highly variable by individual, biologically informed state-based models appeared effective to control for variability in energy proxies across different functional contexts. These results and Chapter 5 “linking buzzes to prey” demonstrate that behavioural context is a signal that can aid understanding of how individual non-lethal disturbance responses can impact fitness.
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Bui, Ann. "Beach burial of cetaceans implications for conservation, and public health and safety : a thesis submitted through the Earth & Ocean Sciences Research Institute, and School of Applied Sciences, Auckland University of Technology in partial fulfillment [sic] of the degree of Master of Applied Science, March 2009." Click here to access this resource online, 2009. http://hdl.handle.net/10292/669.
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Every year hundreds of cetaceans strand on New Zealand beaches. Options for dealing with disposal of their carcasses are few, creating significant problems for the Department of Conservation (DOC). More often than not their carcasses are buried in beaches at or just above high water mark, near where the animals have stranded. The primary objective of this thesis is to determine the effects of cetacean burial on beach sediments, and evaluate potential health and safety risks associated with this practice. A secondary objective of this thesis is to appraise the appropriateness of one location DOC has repeatedly transported cetacean carcasses to and buried within beach sediments, Motutapu Island in Waitemata Harbour. The chemical effects of cetacean burial over a six-month period are reported for two sites at which animals were buried in 2008, Muriwai and Pakiri beaches; the biological effects of this burial are reported for one of these sites, Muriwai Beach, 12 months post burial. Intertidal faunal and floral inventories are provided for six sites around Motutapu Island, and these then compared and contrasted with inventories compiled from an additional 290 intertidal sites between Whangarei Heads and Tauranga Harbour, North Island East Coast, to appraise the relative uniqueness of intertidal species diversity around Motutapu Island. At both Muriwai and Pakiri beaches, nitrogen and phosphate concentrations in surface sands changed considerably following cetacean burial, although over six months the effect was localized and elevated concentrations of these two chemicals that could be attributed to a buried carcass did not extend more than 40 m from the site of whale burial. Deep-core profiles revealed nitrogen and phosphate concentrations at and in the immediate vicinity of cetacean burial approximately six months after burial to be markedly elevated to the level of the water table, but elevated concentrations attributable to the buried carcass were not observed greater than 25 m from the site of burial. Elevated concentrations of nitrogen and phosphates in beaches persist in surface sediments for at least six months post burial. Twelve months post cetacean burial no significant difference in species richness or abundance were apparent in intertidal communities extending along transects proximal to and some distance from the Muriwai Beach carcass; there is no evidence for any significant short-term (to 12 months) biological effects of cetacean burial in beaches. Of those shores on Motutapu Island accessible by earth-moving equipment and large vessels capable of dealing with and transporting large cetacean carcasses, Station Bay appeared to be the most appropriate site for whale burial. However its small size and relatively high biological value (fairly high species richness for comparable shores between Whangarei Heads and Tauranga) renders it an inappropriate long-term option for whale burial. Other shores on Motutapu Island host some of the highest species richness of all shores surveyed between Whangarei Heads and Tauranga Harbour, rendering them entirely inappropriate locations for burying cetaceans, over and above other variables that may influence disposal location identification (such as archaeological sites, dwellings and accessibility). Motutapu Island is not considered an appropriate location for cetacean burial within beaches. Alternative disposal strategies need to be explored for dealing with cetaceans that strand on Auckland east coast beaches. Although burial is the most convenient and most economical strategy to dispose of cetacean carcass, especially in mass stranding events or when cetaceans are of large size, and the biological effects of this practice are not considered significant (for the one whale that could be studied), persistent enrichment of beach sediments with organic matter could result in prolonged persistence of pathogens in beaches, causing unforeseen risks to human health and safety. Recommendations are made to minimize possible threats to public following burial of cetaceans in beaches, until the potential health risks of burial are more fully understood.
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Drake, Summer Elizabeth. "Sensory hairs in the bowhead whale (Cetacea, Mammalia)." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1406300822.
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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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Caillat, Marjolaine. "Assessing and correcting for the effects of species misclassification during passive acoustic surveys of cetaceans." Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/4209.
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In conservation ecology, abundance estimates are an important factor from which management decisions are based. Methods to estimate abundance of cetaceans from visual detections are largely developed, whereas parallel methods based on passive acoustic detections are still in their infancy. To estimate the abundance of cetacean species using acoustic detection data, it is first necessary to correctly identify the species that are detected. The current automatic PAMGUARD Whistle Classifier used to automatically identify whistle detection of cetacean species is modified with the objective to facilitate the use of these detections to estimate cetacean abundance. Given the variability of cetacean sounds within and between species, developing an automated species classifier with a 100% correct classification probability for any species is unfeasible. However, through the examples of two case studies it is shown that large and high quality datasets with which to develop these automatic classifiers increase the probability of creating reliable classifiers with low and precise misclassification probability. Given that misclassification is unavoidable, it is necessary to consider the effect of misclassified detections on the number of observed acoustic calls detected and thus on abundance estimates, and to develop robust methods to cope with these misclassifications. Through both heuristic and Bayesian approaches it is demonstrated that if misclassification probabilities are known or estimated precisely, it is possible to estimate the true number of detected calls accurately and precisely. However, misclassification and uncertainty increase the variance of the estimates. If the true numbers of detections from different species are similar, then a small amount of misclassification between species and a small amount of uncertainty in the probabilities of misclassification does not have a detrimental effect on the overall variance and bias of the estimate. However, if there is a difference in the encounter rate between species calls associated with a large amount of uncertainty in the probabilities of misclassification, then the variance of the estimates becomes larger and the bias increases; this in return increases the variance and the bias of the final abundance estimate. This study despite not bringing perfect results highlights for the first time the importance of dealing with the problem of species misclassification for cetacean if acoustic detections are to be used to estimate abundance of cetaceans.
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Lambert, Emily. "The resilience of whale-watching tourism to climate change impacts on cetacean distribution." Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=186627.
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Whale-watching tourism depends upon the continued presence of cetacean species within a specific area. However, current evidence suggests that the distribution and/or abundance of cetaceans may alter in response to continued changes in sea surface temperature with global climate change (GCC). This thesis develops and applies a framework for evaluating the resilience of whale-watching tourism to these potential temperature-induced shifts in cetacean distribution. The framework identifies three key components that are likely to affect the vulnerability of an operator to climate change impacts on cetacean occurrence (and tourist numbers). These are the likelihood of observing a cetacean, the type of whale-watching trip, and the type of tourist. Together with an examination of an operator's adaptive capacity, these data provide the type of information required to make an assessment of resilience. Using Western Scotland as a case study, framework components were populated using species distribution modeling, a motivation-based segmentation of whale-watchers, an examination of tourist's attitudes to scenarios of a changing environment and a segmentation of trip activity. Finally, data on potential vulnerability were combined with investigation of an operator's adaptive capacity (using semi-structured interviews) to make an evaluation of resilience to climate change. Our results highlight four key findings: (1) operators have high inherent resilience to a variable environment in which uncertainty is accepted, (2) vulnerability to climate change is influenced by the type and number of trips offered by whale-watch operators, (3) adaptive capacity can be improved through enhanced perceptions of risk, and (4) vulnerability to climate change is not independent from vulnerability to other factors. Future research should focus on those areas where whale-watching is less diverse, more specialised and where, currently, the climate is less variable, as it is in these regions that vulnerability may be highest and, most likely, capacity to develop resilience at its lowest.
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Browne, Raymond Walter. "The passive acoustic coding and tracking of cetaceans." Thesis, University of Birmingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368521.
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Harris, Danielle V. "Estimating whale abundance using sparse hydrophone arrays." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/3463.
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Passive acoustic monitoring has been used to investigate many aspects of marine mammal ecology, although methods to estimate absolute abundance and density using acoustic data have only been developed in recent years. The instrument configuration in an acoustic survey determines which abundance estimation methods can be used. Sparsely distributed arrays of instruments are useful because wide geographic areas can be covered. However, instrument spacing in sparse arrays is such that the same vocalisation will not be detected on multiple instruments, excluding the use of some abundance estimation methods. The aim of this thesis was to explore cetacean abundance and density estimation using novel sparse array datasets, applying existing methods where possible, or developing new approaches. The wealth of data collected by sparse arrays was demonstrated by analysing a 10-year dataset collected by the U.S. Navy's Sound Surveillance System in the north-east Atlantic. Spatial and temporal patterns of blue (Balaenoptera musculus) and fin whale (Balaenoptera physalus) vocal activity were investigated using generalised additive models. Distance sampling-based methods were applied to fin whale calls recorded by an array of Ocean Bottom Seismometers in the north-east Atlantic. Estimated call density was 993 calls/1000 km².hr⁻¹ (CV: 0.39). Animal density could not be estimated because the call rate was unknown. Further development of the call localisation method is required so the current density estimate may be biased. Furthermore, analysing a single day of data resulted in a high variance estimate. Finally, a new simulation-based method developed to estimate density from single hydrophones was applied to blue whale calls recorded in the northern Indian Ocean. Estimated call density was 3 calls/1000 km².hr⁻¹ (CV: 0.17). Again, density of whales could not be estimated as the vocalisation rate was unknown. Lack of biological knowledge poses the greatest limitation to abundance and density estimation using acoustic data.
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Dionne, Lee Elton. "Situating the cetacean: Science and storytelling in Witi Ihimaera's The whale rider." CSUSB ScholarWorks, 2006. https://scholarworks.lib.csusb.edu/etd-project/2883.
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Smith, Jaclyn. "The ecology of Cuvier's beaked whale, Ziphius cavirostris (Cetacea: Ziphiidae), in the Bay of Biscay." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/169023/.
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This dissertation introduces the habitat use and spatial-temporal distribution of Cuvier’s beaked whale (Ziphius cavirostris, Cuvier, 1823) in the Bay of Biscay, from surveys carried out by the Biscay Dolphin Research Programme between 1995 and 2007. I have analysed the spatio-temporal distribution of Cuvier’s beaked whale, using dedicated and opportunistic sightings and the interactions with fixed physical variables (depth, slope and aspect), non-fixed environmental variables (sea surface temperature) in the Bay of Biscay, northeast Atlantic. This study used a differing combination of environmental variables and modelling: GAM (General Additive Model), and ENFA (Ecological Niche Factor Analysis), and PCA (Principal Component Analysis). Geographical Information Systems (GIS) and Remote Sensing were used to achieve this. The habitat preferences of Cuvier’s beaked whale showed strong correlations with water depths >1000m and <4000m and steep slopes, associated with the Capbreton canyon, in the southeast Bay of Biscay and the continental shelf slopes in northern Biscay. Areas of high suitability for Cuvier’s beaked whale were predicted for the Bay of Biscay and predictions showed high habitat suitability areas over continental shelf slopes and submarine canyons. The variety of modelling techniques used to identify the habitat preferences and to predict areas of high suitability for Cuvier’s beaked whale in the Bay of Biscay all proved advantageous. On a global scale, techniques such as these could be applied to help research worldwide for future implementations of protected areas to conserve and maintain this species. The abundance and distribution of Cuvier’s beaked whales varied between years and seasons, with an increase in sightings over time and a seasonal distribution shifting north during spring and summer. Stranding records were also analyzed and compared with the sightings data, which identified regional patterns in seasonal distribution between France, the UK and Ireland. In addition to Cuvier’s beaked whale, this study investigated other deep-diving cetaceans (Northern bottlenose whale, Hyperoodon ampullatus, Sowerby’s beaked whale, Mesoplodon bidens, Sperm whale, Physalus macrocephalus, Pilot whale, Globicephala melas) and non-deep diving cetaceans (Fin whale, Balaenoptera physalus, and Common dolphin, Delphinus delphis) observed in the Bay of Biscay and the English Channel. The Bay of Biscay is the most northerly range of the Cuvier’s beaked whale in the eastern north Atlantic and with year round observations, it could be suggested the population may be resident. This raises the question, could Cuvier’s beaked whale act as a predictor of increasing water temperatures because of climate change by shifting their distribution further north.
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Wensveen, Paul J. "Detecting, assessing, and mitigating the effects of naval sonar on cetaceans." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/8684.
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Effective management of the potential environmental impacts of naval sonar requires quantitative data on the behaviour and hearing physiology of cetaceans. Here, novel experimental and analytical methods were used to obtain such information and to test the effectiveness of an operational mitigation method for naval sonar. A Bayesian method was developed to estimate whale locations through time, integrating visual observations with measurements from on-animal inertial, acoustic, depth, and Fastloc-GPS sensors. The track reconstruction method was applied to 13 humpback whale (Megaptera novaeangliae) data sets collected during a multi-disciplinary behavioural response study in Norwegian waters. Thirty-one controlled exposure experiments with and without active transmissions of 1.3-2 kHz sounds were conducted using a moving vessel that towed a sonar source. Dose-response functions, representing the relationships between measured sonar dose and behavioural responses identified from the reconstructed tracks, predicted that 50% of the humpbacks would initiate avoidance at a relatively high received sound pressure level of 166 dB re 1 µPa. Very similar dose-response functions were obtained for cessation of feeding. In a laboratory study, behavioural reaction times of a harbour porpoise (Phocoena phocoena) to sonar-like sounds were measured using operant conditioning and a psychoacoustic method. Auditory weighting functions, which can be used to improve dose-response functions, were obtained for the porpoise based on the assumption that sounds of equal loudness elicit equal reaction time. Additional analyses of the humpback whale data set provided evidence that ramp-up of naval sonar mitigates harmful sound levels in responsive cetaceans located directly in the path of the source, and suggested that a subset of the humpback whale population, such as mother-calf pairs, and more responsive species would benefit from the use of sonar ramp-up. The findings in this thesis are intended to inform sound exposure criteria and mitigation guidelines for anthropogenic noise exposure to cetaceans.
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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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Poole, David. "Bayesian inference for noninvertible deterministic simulation models, with application to bowhead whale assessment /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/8981.
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Souza, Shirley Pacheco de. "Etnoecologia de cetaceos em comunidades de pescadores de São Sebastião, São Paulo." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315744.
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Orientador: Alpina Begossi<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia<br>Made available in DSpace on 2018-08-09T03:00:31Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007<br>Resumo: A Etnobiologia estuda as interações entre populações humanas e recursos naturais, enfocando a percepção e o conhecimento humano sobre os recursos naturais, a forma como estes são utilizados e as práticas de manejo desenvolvidas pelas sociedades. O conhecimento ecológico local (LEK, de 'local ecological knowlegde¿) tem sido muito útil na elaboração de sistemas de co-manejo envolvendo comunidades locais, instituições do governo e cientistas. Pesquisas sobre o conhecimento dos pescadores em relação à ecologia de baleias e golfinhos iniciaram-se no Brasil na década passada. Os principais objetivos deste estudo são registrar e avaliar o conhecimento dos pescadores de São Sebastião, litoral paulista, em relação à etnotaxonomia (classificação e nomenclatura) de cetáceos, bem como sobre a etnoecologia destes animais obtendo informações sobre áreas de ocorrência, habitat, sazonalidade, dieta, tamanho de grupo, reprodução, predadores e interações com a pesca. Os resultados demonstraram que os pescadores estudados percebem os cetáceos em função de sua saliência morfológica e cultural. As espécies mais reconhecidas e nomeadas por eles foram as de maior tamanho (Eubalaena australis, Tursiops truncatus), as acidentalmente capturadas em redes de espera (Pontoporia blainvillei, Sotalia guianensis) e as mais veiculadas em programas de televisão (Megaptera novaeangliae, Orcinus orca). Encontramos uma alta concordância entre o LEK dos pescadores estudados sobre a ecologia dos cetáceos, o conhecimento de pescadores de outras comunidades do sul e sudeste brasileiro, dados obtidos de pesquisas locais e da literatura científica. Isto demonstra que o conhecimento dos pescadores pode ser útil para a conservação dos cetáceos, especialmente das espécies pouco conhecidas, sugerindo novas linhas de pesquisa e apontando áreas críticas em relação à captura acidental destes animais. Além disto, os pescadores podem contribuir de forma valiosa na elaboração de estratégias alternativas em relação ao uso de redes de pesca, ao passo que sua participação em projetos e planos de manejo pode ser uma forma de valorização da cultura local<br>Abstract: Ethnobiology, a branch of Human Ecology, is the study of the interactions between human population and natural resources, concerning human perception, knowledge, resource uses and management. Local ecological knowledge (LEK) has been empirically built by several human societies and transmitted through generations, shaping their culture. LEK has been especially useful
to design systems of co-management involving local people, government institutions and scientists. Surveys on fishers¿ knowledge about cetaceans¿ ecology are relatively scarce around the world and in Brazil they have begun in the last decade. The main objectives of this study are to record and to evaluate the knowledge of the fishers from São Sebastião, in relation to cetaceans¿ folk taxonomy
and bio-ecological aspects, recording their information about classification, nomenclature, occurrence areas, habitat, seasonality, diet, group size, reproduction, predators and interactions with fisheries. Our results showed that fishers¿ perception about cetaceans was highly influenced by phenotypic and cultural salience of the whales and dolphins. The most recognized and cited species were those of greater size (Eubalaena australis, Tursiops truncatus), the most frequently caught ones (P. blainvillei and S. guianensis) and the most exposed by media (M. novaeangliae and O. orca). The high concordance among the LEK of the fishers from São Sebastião on cetaceans, the knowledge of fishers from other communities of southern and southeastern Brazil, data obtained by local researchers and from literature indicates that fishers¿ knowledge could contribute to cetacean¿s conservation, especially in relation to the less studied cetacean¿s species, pointing out new lines of investigation as well as determining fishing grounds where incidental capture of cetaceans are more critical in the studied areas and indicating possible changes in gillnets operations in order to reduce cetaceans catches. Besides, fishers¿ participation in such researches and co-management plans can be a way to revive and valorize their local culture<br>Mestrado<br>Ecologia<br>Mestre em Ecologia
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Bailey, Taylor Michael. "Delphinids on Display: the Capture, Care, and Exhibition of Cetaceans at Marineland of the Pacific, 1954-1967." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4549.
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When Marineland of the Pacific opened in 1954 on the Palos Verdes Peninsula in greater Los Angeles, it was the second oceanarium in the world and the first on the West Coast. An initial investment of $3 million by Oceanarium Inc., owners of the popular Marine Studios park located near St. Augustine, Florida, ensured that Marineland was built with the same state of the art facilities needed to produce an authentic representation of the ocean floor on land. Building on Marine Studios' success exhibiting bottlenose dolphins (Tursiops truncatus), Marineland's central draw was its performing cetaceans. During the park's early years, its collectors pioneered the capture of Pacific dolphin species, such as the Common dolphin (Delphinus delphis) and the Pacific white-sided dolphin (Lagenorhynchus obliquidens), the short-finned pilot whale (Globicephala macrorhynchus), and were the first to capture a live killer whale (Orcinus orca) in 1961. By exposing audiences to previously unknown species through circus-like performances, Marineland played a central role in changing public perceptions of small cetaceans in the post-World War II era. However, with few prior studies to consult, Marineland curators experimented with their own methods of capture, husbandry, and veterinary care that often resulted in the harm or death of cetaceans under their care. Caretakers contended with animal aggression and sexual behavior, the refusal of animals to perform in show routines, and high mortality. Despite the difficulties posed by exhibiting cetaceans, advertisements, press interviews, and films advanced a contrary narrative that animals under Marineland's care enjoyed the conditions of captivity and performing for an audience. This thesis explores the tension between entertainment and animal care that defined the early years of cetacean captivity in North America.
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Fontanesi, Elena. "Habitat use of migrating dwarf minke whales (Balaenoptera acutorostrata subspecies) in Tasmanian waters." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/9754/.
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The Great Barrier Reef hosts the only known reliable aggregation of dwarf minke whale (Balaenoptera acutorostrata subspecies) in Australian waters. While this short seasonal aggregation is quite predictable, the distribution and movements of the whales during the rest of their annual cycle are poorly understood. In particular, feeding and resting areas on their southward migration which are likely to be important have not been described. Using satellite telemetry data, I modelled the habitat use of seven whales during their southward migration through waters surrounding Tasmania. The whales were tagged with LIMPET satellite tags in the GBR in July 2013 (2 individuals) and 2014 (5 individuals). The study area around Tasmania was divided into 10km² cells and the time spent by each individual in each cell was calculated and averaged based on the number of animals using the cell. Two areas of high residency time were highlighted: south-western Bass Strait and Storm Bay (SE Tasmania). Remotely sensed ocean data were extracted for each cell and averaged temporally during the entire period of residency. Using Generalised Additive Models I explored the influence of key environmental characteristics. Nine predictors (bathymetry, distance from coast, distance from shore, gradient of sea surface temperature, sea surface height (absolute and variance), gradient of current speed, wind speed and chlorophyll-a concentration) were retained in the final model which explained 68% of the total variance. Regions of higher time-spent values were characterised by shallow waters, proximity to the coast (but not to the shelf break), high winds and sea surface height but low gradient of sea surface temperature. Given that the two high residency areas corresponded with regions where other marine predators also forage in Bass Strait and Storm Bay, I suggest the whales were probably feeding, rather than resting in these areas.
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Virgili, Auriane. "Modelling distributions of rare marine species : the deep-diving cetaceans." Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS003/document.
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Les cétacés grands plongeurs, cachalots Physeteridae et Kogiidae, et baleines à bec Zipiidae, sont des espèces marines rares. Leur faible densité, aire de distribution étendue et faible disponibilité en surface génèrent de faibles taux d’observations. Cette particularité constitue un défi pour la modélisation d’habitat de ces espèces, préalable à leur conservation. Les modèles doivent gérer l’abondance de zéros qui limitent leur capacité à inférer des résultats écologiquement cohérents. Cette thèse vise donc à trouver une méthodologie adaptée aux jeux de données abondants en zéros, à déterminer comment les variables environnementales influencent la distribution des grands plongeurs et à prédire les zones potentielles qu’ils utilisent. Tester la capacité de prédiction de différents modèles d'habitat confrontés à un nombre décroissant d’observations a permis de souligner la pertinence d’un modèle, même si un minimum de 50 observations est nécessaire pour fournir des prédictions fiables. Des données issues de différentes campagnes visuelles ont été assemblées afin de produire les premières cartes de densités de grands plongeurs à l’échelle de l’océan Atlantique Nord et la mer Méditerranée. Les densités les plus élevées sont prédites dans les eaux entre 1500 et 4000 m de profondeur et près des fronts thermiques, particulièrement le long des pentes continentales et à l'ouest de l'océan Atlantique Nord. Par ailleurs, l’analyse de la transférabilité des modèles a montré une variation des habitats préférentiels en fonction des écosystèmes. Finalement, cette thèse permet de discuter les défis de la modélisation statistique appliquée aux espèces rares et les applications de gestion associées<br>Deep-diving cetaceans, sperm- and beaked whales Physeteridae, Kogiidae and Ziphiidae, are rare marine species. Due to their low densities, wide distribution ranges and limited presence at the water surface, visual surveys usually result in low sighting rates. This paucity of data challenges the modelling of their habitat, prerequisite for their conservation. Models have to cope with a great number of zeros that weakens the ability to make sound ecological inferences. Consequently, this thesis aimed at finding a methodology suitable for datasets with a large number of zeros, determining how environmental variables influence deep-diver distributions and predicting areas preferentially used by these species. By testing the predictive performance of various habitat models fitted to decreasing numbers of sightings, I selected the most suitable model and determined that at least 50 sightings were needed to provide reliable predictions. However, individual surveys can rarely provide sufficient deep-diver sightings thus I merged many visual survey datasets to produce the first basin-wide deep-diver density maps in the North Atlantic Ocean and the Mediterranean Sea. Highest densities were predicted in waters from 1500-4000 m deep and close to thermal fronts ; hotspots were predicted along the continental slopes, particularly in the western North Atlantic Ocean. In addition, a model transferability analysis highlighted that habitat drivers selected by the models varied between contrasted large ecosystems. Finally, I discussed challenges related to statistical modelling applied to rare species and the management applications of this thesis
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Embling, Clare B. "Predictive models of cetacean distributions off the west coast of Scotland." Thesis, University of St Andrews, 2008. http://hdl.handle.net/10023/640.
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The main purpose of this study was to produce and test the reliability of predictive models of cetacean distributions off the west coast of Scotland. Passive acoustic and visual surveys were carried out from platforms of opportunity between 2003 and 2005. Acoustic identifications were made primarily of harbour porpoises (Phocoena phocoena), delphinids, and sperm whales (Physeter macrocephalus). Generalised Additive Models (GAMs) were used to relate species’ distributions to a range of environmental variables over a range of temporal and spatial scales. Predictive models of delphinid distributions showed both inter-annual and inter-month variations. Combining all data for all months and years resulted in a model that combined the environmental influences from each monthly and yearly model. Overall, delphinids were found to associate with the deep (> 400m) warm water (10.5°C-12.5°C), and in areas of deep thermocline. Relationships between sperm whales and environmental variables were consistent over changes in grain size (9 km or 18 km), but not between areas. Although sperm whales were distributed in deep water characterised by weak thermoclines and strong haloclines in the most northerly area (Faroe-Shetland Channel), they were found in deep productive areas with cold surface temperature in the more southerly waters (Rockall Trough). Within the southern Inner Hebrides, high use areas for harbour porpoises were consistently predicted over time (in years) and with differing survey techniques (acoustic versus visual), but not over space (southern Inner Hebrides versus whole of the Inner Hebrides). Harbour porpoises were mainly distributed in areas with low tidal currents and with higher detection rates during spring tides. The use of prey as a predictor variable within models of delphinid distribution shows some promise: there were correlations between delphinid and herring (Clupea harengus) in shelf-waters in 2005 but not in 2004. These models can be used in mitigating acoustic threats to cetaceans in predicted high use areas off the west coast of Scotland.
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Murray, Brent William. "Major histocompatibility complex class II sequence variation in cetaceans : DQ[beta] and DR[beta] variation in beluga (Delphinapterus leucas) and DQ[beta] variation in North Atlantic right whales (Eubalaena glacialis) /." *McMaster only, 1997.
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Van, der Hoop Julie M. "Effects and added drag on cetaceans : fishing gear entanglement and external tag." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/108892.
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Thesis: Ph. D., Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Biology; and the Woods Hole Oceanographic Institution), 2017.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 283-314).<br>Animal movement is motivated in part by energetic constraints, where fitness is maximized by minimizing energy consumption. The energetic cost of movement depends on the resistive forces acting on an animal; changes in this force balance can occur naturally or unnaturally. Fishing gear that entangles large whales adds drag, often altering energy balance to the point of terminal emaciation. An analog to this is drag from tags attached to cetaceans for research and monitoring. This thesis quantifies the effects of drag loading from these two scenarios on fine-scale movements, behaviors and energy consumption. I measured drag forces on fishing gear that entangled endangered North Atlantic right whales and combined these measurements with theoretical estimates of drag on whales' bodies. Entanglement in fishing gear increased drag forces by up to 3 fold. Bio-logging tags deployed on two entangled right whales recorded changes in the diving and fine-scale movement patterns of these whales in response to relative changes in drag and buoyancy from fishing gear and through disentanglement: some swimming patterns were consistently modulated in response. Disentanglement significantly altered dive behavior, and can affect thrust production. Changes in the force balance and swimming behaviors have implications for the survival of chronically entangled whales. I developed two bioenergetics approaches to estimate that chronic, lethal entanglements cost approximately the same amount as the cost of pregnancy and supporting a calf to near-weaning. I then developed a method to estimate drag, energy burden and survival of an entangled whale at detection. This application is essential for disentanglement response and protected species management. Experiments with tagged bottlenose dolphins suggest similar responses to added drag: I determined that instrumented animals slow down to avoid additional energetic costs associated with drag from small bio-logging tags, and incrementally decrease swim speed as drag increases. Metabolic impacts are measurable when speed is constrained. I measured the drag forces on these tags and developed guidelines depending on the relative size of instruments to study-species. Together, these studies quantify the magnitude of added drag in complementary systems, and demonstrate how animals alter their movement to navigate changes in their energy landscape associated with increased drag.<br>by Julie M. van der Hoop.<br>Ph. D.
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Yamato, Maya. "The auditory system of the minke whale (Balaenoptera acutorostrata) : a potential fatty sound reception pathway in a mysticete cetacean." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/77786.
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Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Biology; and the Woods Hole Oceanographic Institution), 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references.<br>Despite widespread concerns about the effects of anthropogenic noise on baleen whales (suborder Mysticeti), we lack basic information about their auditory physiology for comprehensive risk assessments. Hearing ranges and sensitivities could be measured if customized equipment and methods were developed based on how baleen whales receive sound. However, sound reception pathways in baleen whales are currently unknown. This thesis presents an integrative approach to understanding hearing in baleen whales through dissections, biomedical imaging, biochemical analyses, and modeling sound propagation through a whale head using the Finite Element Method (FEM). We focused on the minke whale (Balaenoptera acutorostrata) because it is one of the smallest and most abundant mysticete species, reducing logistical difficulties for dissections and experiments. We discovered a large, well-formed fat body extending from the blubber region to the ears and contacting the ossicles. Although odontocetes, or toothed whales, are thought to use specialized "acoustic fats" for sound reception, no such tissues had been described for mysticetes to date. Our study indicates that the basic morphology and biochemical composition of the minke whale "ear fats" are very different from those of odontocete acoustic fats. However, the odontocete and mysticete fatty tissues share some characteristics, such as being conserved even during starvation, containing fewer dietary signals compared to blubber, and having well-defined attachments to the tympano-periotic complex, which houses the middle and inner ears. FE models of the whale head indicated that the ear fats caused a slight increase in the total pressure magnitude by the ears, and this focusing effect could be attributed to the low density and low sound speed of the ear fats in the models. Fatty tissues are known to have lower densities and sound speeds than other types of soft tissues, which may explain why they are an important component of the auditory system of odontocetes, and perhaps mysticete cetaceans as well. In an aquatic habitat where the pinna and air-filled ear canal are no longer effective at collecting and focusing so'und towards the ears, we propose that both odontocete and mysticete cetaceans have incorporated fatty tissues into their auditory systems for underwater sound reception.<br>by Maya Yamato.<br>Ph.D.
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Friedman, Brielle. "Mass Cetacean Strandings in the United States- Comparison of Northeast and Southeast Strandings, 1997-2011." NSUWorks, 2013. http://nsuworks.nova.edu/occ_stuetd/169.
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Marine mammal mass strandings have been documented for centuries, even going as far back as Aristotle. For just as long, the causes of these mass strandings have been questioned. With every species of cetacean known to have stranded, it is important to find trends to understand and prevent these strandings from occurring. With a heightened awareness of this issue, leading to the creation of marine mammal stranding networks throughout the United States in the 1990s, a more comprehensive approach to data collection has helped with the study. Issues such as seasonality, weather, topography, and disease have all been observed as a potential cause of these events. This study attempted to look at the Atlantic Coast of the United States, and its documented mass strandings from 1997-2011. Stranding data taken from the Northeast and Southeast US Marine Mammal stranding network database provided a basis for the study of these mass strandings. Many of the possible causes of these strandings, including seasonality, location, and species were studied. There was some correlation found between seasons and stranding, meaning there are certain times of the year when a cetacean pod may be more likely to strand.
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Piscitelli, Marina A. "Comparing thoracic morphology and lung size in shallow (Tursiops truncatus) and (Kogia spp.) diving cetaceans." View electronic thesis (PDF), 2009. http://dl.uncw.edu/etd/2009-1/r1/piscitellim/marinapiscitelli.pdf.
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Sensor, Jennifer Dawn. "HEARING AND AGE ESTIMATION IN TWO SPECIES OF ARCTIC WHALE." Kent State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=kent1512125887991219.
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Greenhow, Danielle. "Hearing and Echolocation in Stranded and Captive Odontocete Cetaceans." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4682.
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Odontocetes use echolocation to detect, track, and discriminate their prey, as well as negotiate their environment. Their hearing abilities match the frequency of greatest sensitivity to the higher frequencies used for foraging and navigation. Hearing and echolocation together provide odontocetes with a highly developed biosonar system. This dissertation examines the hearing ability of several odontocete species to understand what signals they can perceive during echolocation. The variability in hearing ranges between species is examined in the context of phylogenetic and ecological differences among taxa. An autonomous hydrophone array is also developed that could be used in an expanded form in field deployments to study echolocation signals in a wider range of species.
Methods for measuring hearing sensitivity include both psychophysical and electrophysiological procedures. Behavioral methods require a large time commitment, for both training and data collection, and can only be performed on captive dolphins. Auditory evoked potential (AEP) methods are non-invasive, rapid measurements of the brain's response to sound stimuli and allow for audiograms to be collected on stranded, high risk dolphins. By determining the hearing abilities of odontocetes either in captivity or during stranding, data can be collected about inter- and intraspecies variability, and the occurrence of hearing impairment. It can also be used as another diagnostic tool to determine the releasability of a stranded animal.
A juvenile male short-finned pilot whale (Globicephala macrorhynchus) that stranded in Curacao had severe hearing impairment at all frequencies tested. Four female short-finned pilot whales tested had the best sensitivity at 40 kHz. The juveniles had greater high frequency sensitivity than the adult pilot whales. Cutoff frequencies were between 80 and 120 kHz.
Hearing sensitivity was determined for the two mother/calf pairs of Risso's dolphins (Grampus griseus) before and after antibiotic treatment in order to measure any potential effects of antibiotic treatment. Greatest sensitivity occurred at 40 kHz and cutoff frequencies were around 120 kHz for all dolphins tested. Changes in hearing sensitivity after antibiotic dosage were 12 dB or less in all cases except one. The adult female Betty showed a threshold shift at 120 kHz of 54 dB from May to June, which partially demonstrates the presence of an ototoxic effect at one frequency. Dosages of antibiotics during drug treatment detailed in this study should be considered safe dosages of antibiotics for Risso's dolphins.
AEP and behavioral methods were used to collect audiograms for three Stenella spp. dolphins. The frequency of best hearing for the Atlantic spotted dolphin and the spinner dolphin was 40 kHz, and their upper cutoff frequencies were above 120 kHz. The pantropical spotted dolphin had the greatest sensitivity at 10 kHz, and had severe high frequency hearing loss with a cutoff frequency between 14 and 20 kHz.
Comparisons of high frequency hearing sensitivities among the species tested show two distinct groups. Short-finned pilot whales and Risso's dolphins have a cutoff frequency below 120 kHz, whereas Stenella spp. dolphins have cutoff frequencies above 120 kHz. Expanding the comparison to include other species, killer whales, pygmy killer whales, false killer whales, and long-finned pilot whales also have cutoff frequencies below 120 kHz. Common bottlenose dolphins, white-beaked dolphins, Indo-Pacific humpback dolphins, rough-toothed dolphins, and common dolphins have cutoff frequencies above 120 kHz. Genetic evidence exists for two subfamilies within Delphinidae (Vilstrup et al., 2011) and those species with cutoff frequencies below 120 kHz belong to the subfamily Globicephalinae and those species with cutoff frequencies above 120 kHz belong to the subfamily Delphininae.
An autonomous, field-deployable hydrophone array was developed to measure free-swimming echolocation. The array contained 25 hydrophones, two cameras, and a synchronization unit on a PVC frame. The distinct click train was used to time-align all 25 channels, and the light was used to synchronize the video and acoustic recordings. Echolocation beam patterns were calculated and preliminary evidence shows a free-swimming dolphin utilizes head movement, beam steering and beam focusing.
Among all areas of cetacean biology more research is necessary to gain a clearer picture of how odontocetes have adapted to function in their acoustic environment. The array system developed can be used to study how dolphins use echolocation in the wild, the impacts of anthropogenic sound on echolocation production, and the potential consequences of high frequency hearing loss.
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Jewell, Rebecca. "Investigating the surfacing and diving behaviour and availability of long-finned pilot whales and quantifying the effects of anthropogenic sound on density and strandings of cetaceans in the northeast Atlantic." Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/6337.
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The size and trend of a population is fundamental to the assessment of its conservation status, yet cetacean abundance data are often biased and lack statistical power to detect trends. As a result, the conservation status of many species is unknown and the population-level effects of conservation pressures such as anthropogenic sound cannot be quantified. Failing to account for cetaceans that are unavailable for detection at the surface during abundance surveys will negatively bias estimates of abundance. Analysis of time-depth data revealed that pilot whale dive and surface interval durations, and availability for detection, varied with time of day, but this bias was accurately estimated using the mean dive and surface interval durations. A global analysis of cetacean density estimates compiled from multiple line-transect surveys incorporated covariates describing availability bias, and other sources of variability, to facilitate the detection of underlying temporal trends. Decadal global trends in cetacean density were detected for four species, while significant yearly ocean-scale trends were detected for six families. Exploratory analysis of data compiled from line-transect surveys found some evidence that trends in the density of minke whales and sperm whales in the northeast Atlantic varied between areas with and without seismic survey effort. However, there were insufficient data to clearly identify chronic exposure to anthropogenic sound from seismic surveys as a driver of population change. Analysis of strandings data from the UK and Ireland identified some evidence that harbour porpoise and sperm whale stranding rates were related to seismic survey effort and wind farm construction, but the results were not conclusive. Large-scale cetacean surveys provide valuable information on the density and spatial and temporal distribution of cetaceans that is vital for monitoring populations, but these surveys cannot replace dedicated studies of the population-level effects of sound on cetaceans.
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Ferrero, Richard C. "Life history and multivariate analyses of habitat selection patterns among small cetaceans in the central North Pacific Ocean /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/5475.
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Cook, Mandy Lee Hill. "Behavioral and auditory evoked potential (AEP) hearing measurements in odontocete cetaceans." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001769.
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Murray, Brent W. "Major Histocompatibility Complex class II sequence variation in cetaceans, DQß and DRß variation in beluga, Delphinapterus leucas, and DQß variation in north Atlantic right whales, Eubalaena glacialis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0019/NQ30162.pdf.
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Godoy, Maria Luiza Motta Pacheco de. "Estudo das taxas reprodutivas e capturabilidade de baleias jubarte Megaptera novaeangliae (BOROWSKI, 1781; CETACEA: MYSTICETI), em sua principal área de concentração para reprodução na costa brasileira (Banco dos Abrolhos, Bahia, Brasil)." Universidade Federal de Juiz de Fora (UFJF), 2007. https://repositorio.ufjf.br/jspui/handle/ufjf/3944.
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Previous issue date: 2007-03-27<br>CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>A caça comercial desenvolvida no início do século XX dizimou populações de baleias jubarte (Megaptera novaeangliae) em muitas regiões do oceano Antártico, entre elas os arredores da ilha Geórgia do Sul. Recentemente, este local foi confirmado como destino migratório das jubartes que se concentram no banco dos Abrolhos, situado entre a Bahia e Espírito Santo, durante a estação de reprodução. Embora em fase de crescimento populacional, este estoque pode apresentar sobrecargas ecológicas tais como alterações na taxa de nascimentos em conseqüência da intensa exploração a que foram submetidos. Este estudo objetivou o levantamento de informações a respeito das taxas brutas de nascimento e de fertilidade de baleias jubarte entre os anos de 1992 e 2003. Como parte desse trabalho, informações sobre comportamento e composição social de animais foto-identificados entre 1989 e 2003, foram relacionadas à probabilidade de captura dos indivíduos. Seus efeitos nas análises de Marcação e Recaptura também foram considerados. O teste G revelou diferenças significativas entre as taxas brutas de nascimento ao longo dos anos, tanto para os registros de foto-identificação (Média = 0,054 ± 0,012; p<0,001) quanto para as informações provenientes de observações a bordo de cruzeiros de pesquisa (Média = 0,192 ± 0,05; p<0,001). Já as taxas de fertilidade se mostraram semelhantes ao longo de todo o período de estudo (Média = 0,87± 0,12; p>0,05). Este trabalho identificou diferenças significativas na probabilidade de captura por fotografia dos indivíduos de acordo com o status reprodutivo (H= 25,01; p = 0,003). A capturabilidade também diferiu em relação ao número de componentes de um grupo, onde associações de até três indivíduos apresentaram probabilidade de captura significativamente maior em relação aos grupos compostos por mais de quatro indivíduos (U = 16; p<0,05). Os resultados aqui identificados revelaram que a maior probabilidade de captura no banco dos Abrolhos se dá em grupos constituídos por três adultos, o que difere de outras áreas de reprodução como Silver Bank, no oceano Atlântico norte, onde os solitários apresentaram maior capturabilidade.<br>The commercial whaling developed during the XX century dizimated many humpback whale (Megaptera novaeangliae) populations of Southern Hemisphere. One of them, found around South Georgia Island, is known to migrate to the Brazilian coast during the breeding season. The intense past exploration have resulted in ecological trends such as changes in reproductive rates. Photo-identification and ship surveys conducted at Abrolhos Bank from 1989 to 2003 were analyzed with the main goal to evaluate how these values are changing over the years. The crude birth rate differed significantly by year (Cruise surveys: Mean = 0,192 ± 0,05; G Test, p<0,001/ Photo-identification: Mean = 0,054 ± 0,012; G Test, p<0,001). Nevertheless, the calving rate showed no significant differences by year (Mean = 0,87± 0,12; G Test; p>0,05). This study verified significant differences in catchability related to the reproductive status (H = 25,01; p = 0,003) and number of individuals composing a group. Associations with three or less individuals showed higher catchability compared to groups composed by four and more animals (U = 16; p<0,05). The highest probability of a whale from Abrolhos Bank be photo-identified was in a group composed by three adults.
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Escalle, Lauriane. "Spatio-temporal interactions between whale sharks, cetaceans and tropical tuna purse-seine fisheries, within a conservation perspective, in the Atlantic and Indian Oceans." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT125/document.
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Dans le cadre de l’Approche Ecosystémique des Pêches (AEP), il est nécessaire d’évaluer l’impact de la pêche thonière tropicale à la senne sur les espèces ciblées et sur les espèces accessoires. Parmi ces dernières, les espèces de la mégafaune, telles que des requins, raies, cétacés, tortues, oiseaux marins, sont souvent emblématiques et vulnérables. Les thoniers senneurs tropicaux recherchent activement à la surface de l’eau tout indice de la présence de bancs de thon (e.g. oiseaux, objets flottants, baleines, dauphins ou requins baleines). Dans l’est de l’océan Atlantique et l’ouest de l’océan Indien, les deux modes de pêches principaux sont les captures de thons en bancs libres et celles sur bancs associés à un objet flottant, naturel ou artificiel, rassemblés ici sur sous le terme de dispositif de concentration de poisson (DCP). Les calées associées aux requins baleines et aux cétacés sont toutefois peu étudiées. L’objectif de cette thèse est donc d’analyser les co-occurrences et/ou interactions spatio-temporelles entre requins baleines, cétacés et pêche thonière à la senne, dans une perspective de conservation de l’écosystème. Ce travail, basé sur des données de livres de bord et d’observateurs scientifiques embarqués, a montré que la co-occurrence pêche thonière/ mégafaune se localise dans des strates spatio-temporelles relativement précises: i) du Gabon à l’Angola (avril–septembre), ii) dans le Canal du Mozambique (juin–septembre) et iii) à l’est des Seychelles (avril–septembre). Les baleines et requins baleines étant planctivores, la co-occurrence avec la pêche à la senne est principalement liée à une forte productivité primaire (appréhendée à travers des proxys tels que la concentration en chlorophylle-a). De plus, les calées sur ces deux groupes étaient assez élevées avant 2000 (jusqu’à 20% des calées), et qu’elles sont moins fréquentes aujourd’hui (AC3 et 1,5% des calées associées à des baleines et des requins baleines, respectivement). L’impact de la pêche à la senne sur ces espèces semble relativement faible au regard du taux de mortalité apparente de 1,4% pour les requins baleines et 5,6% pour les cétacés. Des marquages satellites réalisés sur les requins baleines, confirment ces observations sur le plus long terme, mais la taille de l’échantillon limite la formulation de conclusions définitives. Concernant les dauphins, bien que présents sur les zones de pêche, ils interagissent très peu avec celle-ci, soulignant ainsi une différence majeure avec l’océan Pacifique est où ce mode de pêche est majoritaire. La diversité spécifique des espèces cible et accessoire associées aux calées sur mégafaune a également été étudiée. Les requins baleines sont associés aux listaos et à l’albacore (dans une large gamme de tailles), alors que les baleines le sont principalement à de gros albacores. De plus, la capture accessoire associée à ces deux groupes de mégafaune est relativement faible et dominée par le requin soyeux et la diversité spécifique est proche de celle trouvée sous les bancs libres de thons. Enfin les effets de mesures de conservation vis-à-vis de la mégafaune encerclée ou de mesures de gestion de l’effort de pêche, notamment les moratoires sur DCP réelles ou simulées (e.g. moratoires élargis), ont été analysés. Les premières ont eu un effet limité en terme de captures cibles et accessoires, alors que les moratoires impactent peu le nombre de calées associés à la mégafaune, ceci en raison du décalage spatio-temporel des co-occurrences. Cependant des moratoires élargis pourraient être bénéfiques pour les thons juvéniles et certaines espèces associées. Par l’analyse quantitative des interactions entre la pêche thonière à la senne et la mégafaune, cette thèse apporte des connaissances essentielles sur les espèces étudiées dans le cadre de la mise en place d’une AEP, applicable à la pêche thonière tropicale<br>In the frame of the Ecosystem Approach to Fishery (EAF) management, impact of the tropical tuna purse-seine fishery on targeted and incidentally captured species should be investigated. They may include megafauna species, such as sharks, rays, cetaceans, turtles or sea birds, which often are emblematic and vulnerable species. Tropical tuna purse-seiners actively search, at the surface of the sea, for clues indicating the presence of tuna schools (e.g. birds, floating objects, whales, dolphins or whale sharks). In the eastern Atlantic and western Indian Oceans, the main two fishing modes are sets on free swimming tuna schools and schools associated to natural or artificial floating objects, thereafter called Fish Aggregating Device (FAD). However dedicated studies on fishing sets associated to whale sharks and cetaceans are still lacking. The aim of this thesis is therefore, using logbook and scientific onboard observer data, to investigate the spatio-temporal co-occurrences and/or interactions between whale sharks, cetaceans and the tuna purse-seine fishery within an ecosystem conservation perspective. This work underlines that the megafauna/ fishery co-occurrence occurs in specific spatio-temporal strata: i) Gabon to Angola (April–September), ii) the Mozambique Channel (June–September), and iii) East of Seychelles (April–September). As baleen whales and whale sharks are filter feeders, the co-occurrence with the purse-seine fishery was mostly linked to highly productive environments (i.e. using proxys including chlorophyll-a concentration). In addition fishing sets involving megafauna were relatively high before 2000 (up to 20% of the sets), but are nowadays less frequent (AC3 and 1.5% of the sets associated to baleen whales and whale sharks). The purse-seine fishery appears to have a relatively low impact on megafauna species with mortality rates of 1.4% for whale sharks and 5.6% for cetaceans. Whale shark satellite tagging also confirms these results on the longer term, but the low sample size precludes any final conclusion. While dolphins are present in fishing areas, very few interactions with the fishery was detected, which highlights the striking difference with the eastern Pacific Ocean where half the sets are associated to dolphin herds. In addition, the diversity of targeted and bycatch species captured under whale shark and baleen whale sets was also investigated. Whale sharks are principally associated to skipjack and yellowfin (of various sizes) tunas and baleen whales mostly to large yellowfin tuna. In addition, bycatch species associated to these two megafauna groups was relatively low and dominated by the silky shark, and bycatch diversity was close to the one found for free swimming tuna schools. Finally, real and/or simulated encircled megafauna conservation measures or fishing effort management measures (especially FAD moratoria including larger ones) were investigated. The first ones were found to have limited consequences on tuna catch and bycatch. Conversely FAD moratoria had limited impacts on the number of megafauna associated fishing sets, due to the fact that the main spatio-temporal strata of megafauna and FAD sets differ. However larger and longer moratoria could be beneficial for juvenile tuna and some bycatch species. Overall, this thesis has lead to increase the knowledge on megafauna/ fishery interactions, essential in the general framework of setting up an EAF in the tropical tune purse-seine fishery
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Maldini, Daniela. "Abundance and distribution patterns of Hawaiian odontocetes focus on Oʻahu /". 2003. http://proquest.umi.com/pqdweb?index=0&did=764803641&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1233176917&clientId=23440.
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Reeb, Desray. "Comparative anatomy of the larynx of the minke whale, Balaenoptera acutorostrata and the pygmy right whale, Caperea marginata." Diss., 1997. http://hdl.handle.net/2263/29758.
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Gibb, Giselle Renee. "Humpback whales (Megaptera novaeangliae) in the South Pacific breeding grounds : an allocation from feeding areas and an abundance estimate of whales specific to French Polynesia waters." Thesis, 2009. http://hdl.handle.net/1957/11995.
Full textAbstract:
South Pacific humpback whales were devastated by commercial whaling in their
Antarctic feeding areas during the 20th century. Understanding migratory
connections and current abundance of these isolated breeding stocks is crucial
for the allocation of historical Antarctic catches in population dynamic models
used to assess current recovery. However, only a small number of migratory
connections have been documented between Oceania breeding stocks within the
South Pacific and feeding areas in the Antarctic. In addition, little is known about
abundance of these stocks which encompass a vast oceanic region. For this
thesis I first used mixed-stock analysis (MSA) to allocate migratory connections
from four Antarctic feeding areas (n=142) to seven South Pacific breeding stocks
(n=1,373), including four in Oceania, based on genetic marker frequencies. The
use of this method was justified by the breeding stocks showing genetic
differentiation at the haplotype level with an F[subscript ST] value of 0.027 (p-value <0.001).
The results showed a relatively strong connection of Western Australia to
Antarctic Area IV, Tonga to the border of Antarctic Area VI/I, Colombia to the
Antarctic Peninsula, and a split allocation of Eastern Australia and New
Caledonia to Antarctic Area V. This study provides the first population-level
information supporting previous individual-based studies that humpback whale
migration may not necessarily be direct north south. Next, utilizing capture-recapture
methodology of unique humpback whale fluke photographs, I
estimated abundance of one of the least studied Oceania breeding stocks,
French Polynesia, a stock which also showed no significant migratory allocation
using MSA. Taking into consideration the possible advantages of using Quality
Control (QC) photographs to minimize bias in matching, estimates were
generated using the complete photo catalogue and also using only photographs
adhering to QC criteria. I found that the choice of using QC has an effect on the
abundance generated and discuss the implications of this finding. Despite the
photo catalogue used, the French Polynesia stock is estimated to number less
than 1,900 individuals. Lastly, to provide additional information on the French
Polynesia stock I used photo-identification to compare French Polynesia whales
to whales in the Antarctic Peninsula and Strait of Magellan (Antarctic Area I), a
possible migratory connection suggested by previous microsatellite genotyping.
No conclusive matches were found. Although this does not discount the
possibility of a few migrants traveling between these regions it does indicate the
Antarctic Peninsula and the Strait of Magellan are not primary feeding areas of
French Polynesia. This new information regarding abundance and migration of
French Polynesia whales is important for the Comprehensive Assessment of
Southern Hemisphere humpback whales. This document is currently being
completed as the International Whaling Commission considers the next critical
steps in recovery for Oceania humpback whales stocks.<br>Graduation date: 2010
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O'Brien, Kristin. "POPULATION STATUS AND SOCIAL STRUCTURE OF NORTHERN BOTTLENOSE WHALES (HYPEROODON AMPULLATUS) ON THE SCOTIAN SHELF." 2013. http://hdl.handle.net/10222/35342.
Full textAbstract:
I examined the dynamics of an endangered population of northern bottlenose whales over a 23-year period during which its prime habitat, the Gully canyon, was made a Marine Protected Area (MPA). Using mark-recapture techniques on photo-identifications I estimate a current population of 116 animals (95% CI=101-130). The population size and sex-ratio have remained stable since before the MPA designation suggesting this population is persisting. I used photo-identifications and high definition videography to examine the social organization of northern bottlenose whales, including behavioural synchrony. Relationships are highly variable; most associations are short-lived, but there are also long-term preferred associations lasting from several years (female/immature dyads) to over a decade (mature male dyads). I found little, if any, division of the social community. Synchronized breathing is common, precise, and appears to vary with behaivoural context. Although speculative, synchronized breathing might play a role the maintenance of general social relationships within this population.
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Moors, Hilary B. "Acoustic Monitoring of Scotian Shelf Northern Bottlenose Whales (Hyperoodon ampullatus)." 2012. http://hdl.handle.net/10222/15238.
Full textAbstract:
An important step for protecting Endangered species is the identification of critical habitat. This can be especially challenging for deep ocean species. Northern bottlenose whales (Hyperoodon ampullatus) are deep-diving beaked whales of the North Atlantic. A population of this species occurs along the edge of the Scotian Shelf primarily in three submarine canyons that have been identified as critical habitat for the population: the Gully (the largest submarine canyon off eastern North America), Shortland Canyon and Haldimand Canyon. The Scotian Shelf population is considered Endangered mainly due to its small numbers and the anthropogenic threats it faces. The primary objective of my research was to further identify critical habitat of the population using passive acoustic monitoring, increasing knowledge of how the whales use the canyons and adjacent areas throughout the year. A review of the literature on cetacean associations with submarine canyons indicates that various mechanisms may act to attract cetaceans to these features. While many different species occur in canyons globally, they appear to be particularly important habitat for beaked whales. I developed an automated click detection algorithm customized for detecting northern bottlenose whale echolocation clicks, and long-term acoustic recordings were analyzed to examine the presence and relative abundance of northern bottlenose whales on the Scotian Slope over various spatial and temporal scales. The whales occurred in the area consistently throughout the year and all three canyons, as well as the area between canyons, appeared to be important foraging grounds for the population. The whales displayed diurnal foraging patterns. I also investigated niche separation between northern bottlenose whales and sperm whales (Physeter macrocephalus), another deep diving species. The presence of the two species was positively correlated over all spatial and temporal scales examined. These results indicate that areas within and adjacent to the Gully are important foraging grounds for northern bottlenose whales throughout the year. Furthermore, in addition to the canyons themselves, the shelf-edge areas between the Gully, Shortland and Haldimand canyons may constitute critical habitat for the whales. This research will be used to inform management measures relevant to the protection and recovery of this Endangered population.
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Griffin, Isobel. "Caging the seas: cetacean capture and display at Marineland of the Pacific, 1954-1967." Thesis, 2018. https://dspace.library.uvic.ca//handle/1828/9926.
Full textAbstract:
This thesis examines the early years of marine mammal captivity at Marineland of the Pacific
and its impacts on the oceanarium industry, cetacean science, and public perceptions of whales.
Opening in 1954, Marineland was the first oceanarium on the Pacific coast of North America,
the largest oceanarium in the world, and the lead institution in cetacean capture, entertainment,
and marine mammal research. In 1957, Marineland captured and displayed the first pilot whale,
“Bubbles,” and ignited the whale capture industry that still exists sixty years later. Although
often overlooked in scholarly work, Marineland developed innovative capture and display
techniques while expanding animal husbandry knowledge. The park also revolutionized the
marine mammalogy field by providing unprecedented opportunities for scientists to closely
observe, study, and interact with live whales. Furthermore, Marineland’s capture, display, and
portrayal of pilot whales in popular media generated public empathy toward cetaceans and
transformed public perceptions of the animals. Through examinations of scientific papers,
popular publications, interviews, and the Kenneth S. Norris Papers from the University of
California Santa Cruz, a collection containing Norris’s personal scrapbooks, field notes, and
unpublished research, this thesis will show that Marineland of the Pacific was the crucible of
change for marine entertainment, cetacean research, and public perceptions of whales.<br>Graduate<br>2019-07-27
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Bowers, Matthew. "Behavioral Ecology of the Western Atlantic Short-finned Pilot Whale (Globicephala macrorhynchus)." Diss., 2015. http://hdl.handle.net/10161/12811.
Full textAbstract:
<p>Social structure is a key determinant of population biology and is central to the way animals exploit their environment. The risk of predation is often invoked as an important factor influencing the evolution of social structure in cetaceans and other mammals, but little direct information is available about how cetaceans actually respond to predators or other perceived threats. The playback of sounds to an animal is a powerful tool for assessing behavioral responses to predators, but quantifying behavioral responses to playback experiments requires baseline knowledge of normal behavioral patterns and variation. The central goal of my dissertation is to describe baseline foraging behavior for the western Atlantic short-finnned pilot whales (Globicephala macrohynchus) and examine the role of social organization in their response to predators. To accomplish this I used multi-sensor digital acoustic tags (DTAGs), satellite-linked time-depth recorders (SLTDR), and playback experiments to study foraging behavior and behavioral response to predators in pilot whales. Fine scale foraging strategies and population level patterns were identified by estimating the body size and examining the location and movement around feeding events using data collected with DTAGs deployed on 40 pilot whales in summers of 2008-2014 off the coast of Cape Hatteras, North Carolina. Pilot whales were found to forage throughout the water column and performed feeding buzzes at depths ranging from 29-1176 meters. The results indicated potential habitat segregation in foraging depth in short-finned pilot whales with larger individuals foraging on average at deeper depths. Calculated aerobic dive limit for large adult males was approximately 6 minutes longer than that of females and likely facilitated the difference in foraging depth. Furthermore, the buzz frequency and speed around feeding attempts indicate this population pilot whales are likely targeting multiple small prey items. Using these results, I built decision trees to inform foraging dive classification in coarse, long-term dive data collected with SLTDRs deployed on 6 pilot whales in the summers of 2014 and 2015 in the same area off the coast of North Carolina. I used these long term foraging records to compare diurnal foraging rates and depths, as well as classify bouts with a maximum likelihood method, and evaluate behavioral aerobic dive limits (ADLB) through examination of dive durations and inter-dive intervals. Dive duration was the best predictor of foraging, with dives >400.6 seconds classified as foraging, and a 96% classification accuracy. There were no diurnal patterns in foraging depth or rates and average duration of bouts was 2.94 hours with maximum bout durations lasting up to 14 hours. The results indicated that pilot whales forage in relatively long bouts and the ADLB indicate that pilot whales rarely, if ever exceed their aerobic limits. To evaluate the response to predators I used controlled playback experiments to examine the behavioral responses of 10 of the tagged short-finned pilot whales off Cape Hatteras, North Carolina and 4 Risso’s dolphins (Grampus griseus) off Southern California to the calls of mammal-eating killer whales (MEK). Both species responded to a subset of MEK calls with increased movement, swim speed and increased cohesion of the focal groups, but the two species exhibited different directional movement and vocal responses. Pilot whales increased their call rate and approached the sound source, but Risso’s dolphins exhibited no change in their vocal behavior and moved in a rapid, directed manner away from the source. Thus, at least to a sub-set of mammal-eating killer whale calls, these two study species reacted in a manner that is consistent with their patterns of social organization. Pilot whales, which live in relatively permanent groups bound by strong social bonds, responded in a manner that built on their high levels of social cohesion. In contrast, Risso’s dolphins exhibited an exaggerated flight response and moved rapidly away from the sound source. The fact that both species responded strongly to a select number of MEK calls, suggests that structural features of signals play critical contextual roles in the probability of response to potential threats in odontocete cetaceans.</p><br>Dissertation
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Yu, Wen-Jyh, and 游文志. "Influence of Whale-watching Boats on Behavior of Cetaceans at Haulien, Taiwan." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/38983317096745326920.
Full textAbstract:
碩士<br>國立東華大學<br>自然資源管理研究所<br>88<br>The whale watching industry was initiated in 1997 in Taiwan. Up to the summer of 1999, there’re more than 12 whale watching boats, it will continue to grow in the nearly future. This study tried to evaluate the short-term impact on the cetaceans by whale watching activities. Nautical investigation was begun in Hualien during the summer time of 1998 and 1999. 241 groups of cetaceans belong to 11 species were recorded, Grampus griseus, Stenella attenuata, Stenella longirostris and Lagenodelphis hosei are the four common species. These four species are investigated the inter-relationship between whale-watching boats and the behavior of cetaceans. First, this study compared the behavior differences of dolphins displayed during “with-boat period” and “no-boat period”. Stenella attenuata, Stenella longirostris and Lagenodelphis hosei showed more frequently the negative responses when they confront the whale-watching boats, but not for the Grampus griseus. When the whale watching boats approach, diving was the most behavioral state for four kinds of dolphins. At the same time, Grampus griseus, Stenella attenuata and Lagenodelphis hosei will increase the frequency of changing directions. The herd of Stenella longirostris dispersed more frequently. In the patterns of surfacing and diving, the duration of surfacing sequence and the ratio of the Grampus griseus, Stenella attenuata and Lagenodelphis hosei and the diving frequency of the Stenella attenuata and Lagenodelphis hosei are significantly increased, but no significant differences for Stenella longirostris. Nevertheless, the swimming speed, number of aerial displays and diving durations in four kinds of whale don’t have significant responses. As a whole, behavioral state, changing direction, and the duration of surfacing sequence of the cetaceans were the most important factors for evaluating the disturbance to the whale watching boats. Secondly, this study analyzed the effects of whale-watching boats to the dolphins. In terms of the position between dolphins and boats, most whale-watching boats choose to get close to dolphins from the back with slow speed. When dolphins are surfed again, they choose more often far from the boats, not in front of them. When the number of boats increases, dolphins became more difficult to approach and the distances between dolphin diving and boats significantly increased. In order to sustain the ecological environment and economical benefit, this study provided three suggestions: (1)limiting the capacity of boats,(2)controlling the driving behavior of whale-watching boats, and (3) monitoring the cetacean ecology.
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"Is Whale Watching a Win-Win for People and Nature? An Analysis of the Economic, Environmental, and Social Impacts of Whale Watching in the Caribbean." Doctoral diss., 2017. http://hdl.handle.net/2286/R.I.46226.
Full textAbstract:
abstract: Whale watching has been hailed by environmental non-governmental organizations like Greenpeace and the International Fund for Animal Welfare as a responsible form of tourism that has the potential to enhance conservation outcomes for cetaceans, while also supporting the economic development of coastal communities. Tourism research suggests that while it is possible for whale watching to provide these benefits, it may also have considerable costs to members of host communities and cetaceans. My dissertation sought to gather data on the economic, ecological, and social impacts of whale watching in the Caribbean in order to evaluate the industry's performance in the region. My project thus took the form of three sub-projects. The first used an ordinary least squares analysis to examine the relationship between Caribbean country characteristics and whale watching expenditures. This analysis showed that a country's level of development changes the strength of correlations, that mass tourism development is negatively associated with whale watching profits, and that cetacean biodiversity and whale watching regulations designed to protect cetaceans both had positive relationships with the whale watching industry. In the second sub-project, I developed an index of Caribbean cetacean vulnerability to the negative impacts of whale watching with a traditional literature review informed by systematic methods. The index illustrated that both target and non-target species had vulnerabilities, and that regulations addressing these issues in the Caribbean were lacking overall. Considerable gaps in data were also identified. Finally, I used qualitative interviews in Dominica and the Dominican Republic to gather information on resident perceptions of whale watching. This analysis revealed overall positive perceptions of the industry in both countries, but also uncovered considerable levels of social conflict surrounding whale watching. Taken together, the results of my study suggest that better regulatory structures, investment in the local community, and efforts to maximize cooperation are needed in order for the Caribbean whale watch industry to better serve local communities, while mitigating its impacts on cetaceans.<br>Dissertation/Thesis<br>Doctoral Dissertation Environmental Social Science 2017
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Yu, Hsin-Yi, and 余欣怡. "Songs of a humpback whale (Megaptera novaeangliae) in Taiwan and evolution of communication in cetaceans." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/51640372386967834928.
Full textAbstract:
碩士<br>國立中山大學<br>海洋生物研究所<br>90<br>Humpback whales (Megaptera novaeangliae) belong baleen whales. They migrate between high-latitude summer feeding regions and low-latitude wintering regions where calving and make place.There were 1~60 humpback whales whaled every year during 1920~1967 in southern Taiwan. However, only a few sights were recorded in the past twenty years.
A male humpback whale was sighted on the east coast of Taiwan in March, 2000. His songs recorded during between three-day tailing were analysed. There were five themes and nine units in the songs, a complete song duration lasted about 14.2 minutes. The maximal sound pressure level was 189.6 dB (n=32, SEM =2.81). The acoustic characters (i.e., signal duration, time between two signals, theme duration, fundamental frequency) of the songs were not significant different. A visual comparison of the spectrograms of the sound units from this particalar whale with those northwest Pacific Ocean showed similarity. This individual was a member of the population in the northwest Pacific Ocean. This conclusion was also supported by the result of Photo-ID of its fluke.
Ceatceans live in the water and develop the special model to produce sounds. There are two kinds of communicative signals: pulses and whistles. These two signals were characters of phylogenetic relationship and the outgroup was red deer. There were two monophyletic groups. Evolution of communicative signals in cetaceans was whistle existent and added the pulses signals. Last, the whistles lost and only with pulses.
The fumctions of pulse signals in communication was unknown in delphinidae. Sperm whales, pygmy sperm whales, dwarf sperm whales, Baird’s beaked whales and Hector’s dolphins were only use pulse signals. The reason of this change was unclear.
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Alves, Filipe Marco Andrade. "Population structure, habitat use and conservation of short-finned pilot whales Globicephala macrorhynchus in the Archipelago of Madeira." Doctoral thesis, 2013. http://hdl.handle.net/10400.13/600.
Full textAbstract:
This thesis provides information on the grouping structure, survival, abundance, dive
characteristics and habitat preferences of short-finned pilot whales occurring in the
oceanic archipelago of Madeira (Portugal, NE Atlantic), based on data collected
between 2001-2011, and contributes for its conservation. Photo-identification
methods and genetic analyses demonstrated that there is a large degree of variability
in site fidelity, including resident, regular visitor and transient whales, and that they may not be genetically isolated. It is proposed that the pilot whales encountered in Madeira belong to a single population encompassing several clans, possibly three clans of island-associated (i.e. resident and regular visitor) whales and others of transients, each containing two to three matrilineal pods. Mark-recapture methods estimated that the island-associated community is composed of less than 150 individuals and that their survival rate is within the range of other long-lived cetacean species, and that around 300 whales of different residency patterns uses the southern area of the island of Madeira from mid-summer to mid-autumn. No significant trend was observed between years. Time-depth recorders deployed in adult whales during daytime revealed that they spend over ¾ of their time at the surface, that they have a low diving rate, and that transient whales also forage during their passage. The analyses of visual data collected from nautical and aerial line-transect surveys indicate a core/preferred habitat area in the south-east of the island of Madeira. That area is used for resting, socializing, foraging, breeding, calving and birthing. Thus, that area should be considered as an important habitat for this species, at least seasonally (during autumn) when the species is more abundant, and included in conservation plans. No direct threat needing urgent measures was identified, although the impact of some activities like whale-watching or marine traffic should be assessed.<br>Universidade da Madeira
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Gero, Shane. "ON THE DYNAMICS OF SOCIAL RELATIONSHIPS AND VOCAL COMMUNICATION BETWEEN INDIVIDUALS AND SOCIAL UNITS OF SPERM WHALES." 2012. http://hdl.handle.net/10222/15852.
Full textAbstract:
Within-population behavioural variation can greatly affect the ecology of a species and the outcome of evolutionary processes. This study aimed to determine how variable sperm whale social and vocal behaviour is between both individuals and their social units.
The population of whales off Dominica is small and isolated from communities in neighbouring waters. Female and immature whales live together in social units containing about 7 animals. I analysed their social relationships and their ‘coda’ communication signals using an unparalleled dataset of social and vocal interactions at the level of the individual.
Within units, calves were significant nodes in their social unit’s network, and thus I provide quantitative support for the hypothesis that communal calf care acts as the primary evolutionary driver for group formation in this species.
Social relationships within and between units were diverse, while the spatial spread of individuals within units and their travel speeds were similar among all of the units. I identified long-term patterns of association between units consistent over decadal time scales.
Social units had characteristic vocal repertoires, but all were dominated by the ‘1+1+3’ and ‘5R’ coda types. Differences between units resulted from some units using specific 4-click coda types. Units and individuals used different accents on their ‘5R’ codas, but the ‘1+1+3’ coda was stereotyped across all individuals and units studied. The repertoires of different units were as similar as units within vocal clans in the Pacific. My results support the hypothesis that the ‘5R’ coda may function in individual identification. The stability of the ‘1+1+3’ coda may be the result of selection for a marker of clan membership. Individual repertoires differed consistently across years; and contrary to an existing hypothesis, new mothers did not vary their repertoire to be more distinct after giving birth. However, calves did use a class-specific ‘3+1’ coda.
In summary, sperm whale social and vocal behaviour vary between individuals and among units. Variation in the social and vocal behaviour of female sperm whales results from a trade-off between individuality and conformity within units and clans.
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Olio, Marília Pereira. "Temporal variability of cetaceans in the Azores and its relation with oceanographic features as derived by satellite imagery." Master's thesis, 2017. http://hdl.handle.net/10400.3/4637.
Full textAbstract:
Dissertação de Mestrado, Estudos Integrados dos Oceanos, 28 de abril de 2017, Universidade dos Açores.<br>O Arquipélago dos Açores (Portugal) é composto por nove ilhas vulcânicas no Nordeste Oceano Atlântico e detém uma elevada diversidade de cetáceos, com 28 espécies documentadas. Este é o primeiro estudo nos Açores, que avalia a utilidade de dados do turismo de observação de baleias para estudos científicos sobre a distribuição dos cetáceos, e que relaciona a sua ocorrência e variabilidade com imagens MODIS/AQUA de clorofila a (Chla) e temperatura à superfície (SST) com 1 km de resolução obtidas através do site da NASA Ocean Color. Neste estudo, cinco anos de dados de campo (2010-2014) foram utilizados para avaliar a presença das baleias azul, comum, sardinheira e bossas. Foram consideradas três escalas temporais (quatro anos em conjunto, anuais e mensais). Dado que o esforço não foi consistente ao longo dos anos, as taxas de avistamento (Encounter rate, ER=avistamentos.esforço-1) foram utilizadas como medidas padronizadas para comparações temporais de presença. Imagens diárias de Chla e SST foram processadas estatisticamente, obtendo-se médias mensais, sazonais, anuais, tendências e anomalias para o período de 2010 a 2014 para a região dos Açores e relacionados com a variabilidade local de quatro espécies de baleias de barbas para tentar explicar as diferenças registadas ao longo dos anos. Os principais resultados mostraram que a presença das quatro espécies de baleias de barbas nos Açores variou entre os anos. Diferenças intra-sazonais foram encontradas para as taxas de presença e estas variaram de acordo com a espécie. A presença de Bm foi observada durante a primavera sugerindo que estas baleias usam os Açores como área de alimentação durante estes meses enquanto estão na sua rota de migração para norte e que, a variação de Chla e o início do crescimento do fitoplâncton são bons indicadores do tempo efectivo destas na região. Resultados semelhantes foram encontrados para a BP, mas a sua associação com Chla e o momento do crescimento do fitoplâncton é posterior à Bm Sendo a Bp mais oportunista e tendo uma dieta mais variada, as suas presas podem estar a níveis diferentes cadeia alimentar. O pico de Bb variou nos meses de primavera e verão e estas diferenças podem ser explicadas pela suposição, já referida por outros autores, de que os Açores provavelmente são visitados por duas populações diferentes de Bb, uma durante a fase de migração na primavera e a segunda durante o final do verão e no outono. Assim sendo, a concentração de Chla seria um parâmetro biológico associado com o pico de Bb apenas para uma das populações. Por último, os picos de presença de Mn foram observados principalmente durante a primavera e o número de meses dos avistamentos duplicou em 2014 e 2015, sugerindo que Mn poderia utilizar os Açores como área de alimentação durante estes meses, durante o seu caminho de migração para norte. A temperatura da superfície do mar, a concentração de Chla e o início do crescimento do fitoplâncton, aqui ilustrados como médias gerais, médias ajustadas (tendências) e anomalias, suportam a hipótese de que o ciclo sazonal e a variabilidade inter-anual são bem demarcados nesta região podendo explicar as diferenças observadas na presença das baleias ao longo os anos. Ao remover o ciclo sazonal, SST é muito conservador ao longo dos anos, com uma ligeira tendência de aumento com o tempo. Com relação à Chla, nem todos os anos apresentam floração de primavera, mas 2010 e 2014 revelam os picos maiores de Chla, coincidindo também com um aumento global de observação das baleias, particularmente para 2014. O uso de plataformas de oportunidade pode dar aos cientistas um meio de recolha de dados sobre uma ampla gama de fauna marinha quando o financiamento da investigação é limitado. No entanto, face às limitações encontradas nos dados de cetáceos, este estudo apresenta novas sugestões de introdução nos protocolos de amostragem por forma a que os dados MONICET possam produzir dados detalhados para fins científicos.<br>ABSTRACT: The Archipelago of the Azores (Portugal) is composed of nine volcanic islands in the northeast Atlantic Ocean and it holds a high diversity of cetaceans, with 28 species documented. This is the first study in the Azores that assesses the utility of whale watching data for scientific studies on cetacean distribution, and that relates their occurrence and variability with 1 km resolution MODIS/AQUA near-surface chlorophyll a (Chla) and Sea Surface Temperature (SST) data obtained from NASA Ocean Color website. In this study, five years of field data (2010-2014) were used to evaluate blue, fin, sei and humpback whales presence. Three temporal scales (four years, yearly, and monthly) were considered. Given that effort was not consistent throughout, then encounter rates (ER=sightings.effort-1) were used as standardized measures for presence temporal comparisons. Daily satellite Chla concentrations and SST values were statistically processed such as to obtain monthly, seasonal, annual averages, trends and anomalies for the period 2010 to 2014 for the Azores region. Baleen whales presence was related with the oceanographic data to infer possible causes for whales inter-annual variability Main results showed that the presence of the four baleen whale species in the Azores varied among the years. Intra-seasonal differences were found for presence rates and these varied with the species. The Bm presence was observed during the springtime suggesting that they use the Azores for foraging activity during these months while they are in their migration journey to north and that the variation of Chla and the initiation of the bloom could determine their time in the area. Similar results were found for Bp but their association with Chla and the timing of the bloom is later than the Bm. Since Bp is more opportunistic and has a varied diet, this happened since their prey could be in another level of the food chain. The peak for Bb varied in the spring and summer months and these differences could be explained by the assumption previously made by other authors, that maybe the Azores is visited by two different stocks of Bb, one during the migration in spring time and the second during late summer and autumn. Furthermore, the Chla concentration could be a biological parameter associated with the peak of Bb only for one stock. Lastly, the presence peaks of Mn were observed mostly during the spring and the number of sightings per month doubled in 2014 and 2015, suggesting that Mn could have foraged during these months while they were in their migration journey to north. Sea surface temperature and Chla concentration overall averages, adjusted averages (trends) and anomalies, as well as, calculations of the timing of the blooms show that the seasonal cycle is strong at these latitudes and inter-annual variability may explain differences in whales presence over the years. By removing the seasonal cycle, SST is very conservative over the years, and its trend reveals slight increase with time. Regarding Chla concentrations, spring blooms are not always observed in the region, but 2010 and 2014 reveal the strongest ones, coincident also with an overall increase in baleen whales observation, particularly for 2014. The use of platforms of opportunity may provide scientists a means of collecting data on a wide range of marine fauna when research funding is limited. Nevertheless, and in face with all the limitations found in the cetacean data, this study presents new suggestions for sampling protocols improvement such data from whale watching in MONICET might yield better possibilities for scientific purposes in the Azores.
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Fernandes, Ricardo André Leite. "Proposta de metodologia e estudo de foto-identificação das baleias-de-Bryde (Balaenoptera edeni e B. brydei) nos Açores e Madeira." Master's thesis, 2015. http://hdl.handle.net/10400.3/3372.
Full textAbstract:
Dissertação de Mestrado em Estudos Integrados dos Oceanos.<br>A baleia-de-Bryde (Balaenoptera edeni) descrita pela primeira vez por J. Anderson em 1878 é uma espécie de baleia-de-barbas que é avistada nos Açores e na Madeira, tendo uma distribuição mundial em águas tropicais e subtropicais. Muito pouco é conhecido sobre as populações do Atlântico Norte. Os objetivos principais deste trabalho consistiram em criar um catálogo de foto-identificação "on-line" que esteja disponível a qualquer interessado e definir uma metodologia para esta espécie. Tentou-se também verificar se existiam reavistamentos entre os Açores e a Madeira e tentar perceber se é a espécie que ocorre nestes arquipélagos é Balaenoptera edeni ou a espécie Balaenoptera brydei. Toda a informação recolhida e analisada proveio de avistamentos e fotografias das baleias-de-Bryde, obtidos de entidades de "whale whatching".
Os resultados mostraram que nos Açores nem todos os anos são observadas as baleias-de-Bryde, mas na Madeira são mais frequentes. Em ambos os arquipélagos os meses de julho a setembro são os que apresentam mais avistamentos. Foram identificados 73 indivíduos desde 2004 a 2014, dos quais 4 deles foram observados nos Açores e na Madeira. Foram avistados um par fêmea-cria nos Açores e três pares na Madeira tendo sido observado o mesmo indivíduo com crias diferentes num espaço de 2 anos. As características observadas nos dois arquipélagos indicam tratar-se da espécie Balaenoptera brydei porém são necessários mais dados para se retirarem conclusões. Seria importante para a continuação deste estudo que os dados continuassem a ser retirados, e que todos os avistamentos tivessem posição geográfica disponível. Além disso ter dados das Canárias era igualmente relevante para conhecer a dinâmica desta espécie na região biogeográfica da Macaronésia.<br>ABSTRACT: The Bryde's whale, first described by J. Anderson in 1878, it's a baleen whale sighted in the Azores and Madeira. Very little is known about the populations of the North Atlantic. The main objectives of this study were to create an on-line catalogue of photo-identification that is available to anyone and to define a methodology for this study on this species. We also tried to study re-sightings of the Bryde's whale between the Azores and Madeira and to understand if the species that is sighted in the both archipelagos is Balaenoptera edeni or Balaenoptera brydei. All the data gathered and analyzed came from the sightings and photos of Bryde’s whale and provided by whale watching companies.
The results shown that the in the Azores the Bryde's whales are not sighted every year but in Madeira they are more frequently seen. On both archipelagos the months with the biggest amount of sightings for this species are from July to September.
Seventy three different individuals were identified since 2004 to 2014 and four of them were sighted in both archipelagos. One pair cow-calf was seen in the Azores and three pairs in Madeira. One of the individual sighted was seen with two different calves in two years. The observations from both archipelagos suggest that the species occurring in this areas are Balaenoptera brydei, although more data is needed to reach to a conclusion. It would be very important to continue this study in the future to gather more data with the GPS position. The availability of data from Canaries would be very interesting to understanding the dynamics of this species on the Macaronesia biogeographic area.