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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Behavioural ecology of Bottlenose dolphins (Tursiops sp.) and interactions with humans in southeast Queensland, Australia

Brieze, I. Unknown Date (has links)
No description available.
72

Buying the vineyard, different options for living playing and hoping in non-violence and safety, DOLPHINS

Feeser, Pamela A. January 2006 (has links)
Thesis (D.Min.)--South Florida Center for Theological Studies, 2003. / DOLPHINS stands for "Different Options for Living Playing and Hoping In Non-violence and Safety" Includes bibliographical references.
73

Identificação e análise das áreas domicilares do boto-cinza, Sotalia guianensis (Van Bénéden, 1864), no estuário de Cananéia, São Paulo /

Oshima, Júlia Emi de Faria. January 2011 (has links)
Orientador: Marcos César de Oliveira Santos / Banca: Alexandre de Freitas Azevedo / Banca: Katia Maria Paschoaletto Micchi de Barros Ferraz / Resumo: O conceito de área domiciliar, ou home range, foi definido como "a área utilizada por um indivíduo em suas atividades normais de forrageamento, reprodução e cuidado da prole". O estudo sobre o uso de área pode fornecer informações sobre padrões de reprodução, organização e interações sociais, recursos limitantes e componentes importantes do habitat. É escasso o conhecimento sobre as características relacionadas à forma com que o boto-cinza, Sotalia guianensis (Van Bénéden, 1864) (Cetacea, Delphinidae), usa seu habitat. O objetivo deste estudo foi identificar e analisar as áreas domiciliares de S. guianensis no estuário de Cananéia (~2503‟S; 47o55‟W), litoral sul de São Paulo. Os esforços para coleta de dados foram realizados entre os anos de 2000 e 2010 com o uso da técnica de foto-identificação. A referida técnica permite aos investigadores identificar indivíduos de uma população ao longo do tempo e do espaço. De 135.918 fotografias batidas, 34.086 (25%) foram consideradas úteis para identificações individuais. Duzentos e cinco indivíduos foram catalogados através das marcas identificadas em suas nadadeiras dorsais. Utilizando os pontos de localização dos indivíduos identificados foi possível estimar o tamanho das áreas domiciliares de 31 indivíduos que apresentaram 20 ou mais avistagens em dias distintos. Quatro métodos foram testados com a extensão Home Range Tools para o ArcGIS 9.2 para analisar e comparar as áreas domiciliares estimadas: Mínimo polígono convexo (MPC), kernel adaptativo com validação cruzada de quadrados mínimos (LSCV), kernel fixo com largura de referência (href) e kernel fixo com LSCV / Abstract: The concept of home range was described elsewhere as "the area traversed by the individual in its normal activities of food gathering, mating and caring of young". Home range studies provide significant insights on mating patterns, social organization and interactions, limiting resources and important components of the habitat. Knowledge about habitat use by Guiana dolphins, Sotalia guianensis (Van Bénéden, 1864) (Cetacea, Delphinidae), is still scarce. The aim of this study was to identify and analyze homes ranges of Guiana dolphins in the Cananéia estuary (~2503‟S; 47o55‟W), southern São Paulo state. Photo-identification efforts were conducted between 2000 and 2010. This technique allows investigators to identify individuals in a population through time and space. From a total 135,918 pictures taken, 34,086 (25%) were good quality pictures useful for individual identification. Two hundred and five individuals were catalogued based on permanent notches in their dorsal fins. Using the locations of the identified individuals, it was possible to estimate home range sizes of 31 individuals which had 20 or more sightings in distinct days. Four methods were tested with the Home Range Tools extension for ArcGIS 9.2, to analyze and compare the estimated home ranges: minimum convex polygon (MCP), adaptative kernel with least squares crossvalidation (LSCV), fixed kernel with reference bandwidth (href) and fixed kernel with LSCV / Mestre
74

Caracteriza??o da frequ?ncia de atividades a?reas do golfinho-rotador, Stenella longirostris (Gray, 1828), na Ba?a dos Golfinhos do Parque Nacional Marinho de Fernando de Noronha

Carli, Rita de C?ssia de 22 March 2012 (has links)
Made available in DSpace on 2014-12-17T15:37:09Z (GMT). No. of bitstreams: 1 RitaCC_DISSERT.pdf: 2507687 bytes, checksum: 4eeca6582506786804976f0255257b80 (MD5) Previous issue date: 2012-03-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The aerial activities, leaps and slaps with parts of the body in the surface of water, are part of the behavioral repertoire of several species of cetaceans. Among them, the spinner dolphin, Stenella longirostris, shows greater diversity in such behavior. For the spinner dolphins of Fernando de Noronha, the aerial activities are classified as vertical and horizontal, with eight patterns to be noted (tail slap, head slap, motor boating, partial leap, leap, spin, tail over head and tail over head with spin) discriminated between these categories. Such behaviors can be used as a parameter to identify behavioral changes, as well as patterns of daily and seasonal activity. In this manner, this study aimed to characterize the frequency in performance of such activity while the dolphins were within the Dolphin Bay of Fernando de Noronha, and verify possible daily and seasonal hourly fluctuations on such behaviors. The data analyzed in this study was acquired during the period of January 2006 through December 2010, totaling 1431 days of observation from land set point, with 113027 aerial activities registered, daily average of 72,27 (SD=96,10). During 5478h and 54 min of observation the horizontal aerial activity was the most observed and rotation was the most executed pattern. Greater frequency of execution of aerial activity was observed in adults, but for both adults and calves, was observed a predominance of horizontal activities, with spin being the pattern most executed. Positive correlation was observed between the amount of aerial activity performed and the number of animals inside the Bay. Hourly daily fluctuation was observed in the expression of aerial activities by spinner dolphins, and was observed a peak of activity between 8h and 8h59min for the overall frequency relative of aerial activities, as well as for the categories and patterns. Seasonal differences were observed between the rainy and dry season with the greater amount of activity being observed during the rainy season. Nevertheless, the same profile of frequency relative of aerial activity was observed in both seasons with the peak amount being during the same period. When discriminated the aerial activities in categories and patterns, for both seasons, there was a similar pattern of hourly fluctuation; for most of parameters, higher frequency relative of execution of aerial activity remain between 8h and 8h59min / As atividades a?reas, saltos e batidas com partes do corpo na superf?cie da ?gua, comp?em parte do repert?rio comportamental de diversas esp?cies de cet?ceos. Dentre elas, acredita-se que o golfinho-rotador, Stenella longirostris, seja a esp?cie que apresenta maior agilidade em tais comportamentos. Para os golfinhos-rotadores de Fernando de Noronha, as atividades a?reas s?o categorizadas em atividades a?reas verticais e horizontais, sendo oito (batida de cauda, batida de cabe?a, motor de popa, ca?da, salto, rota??o, invers?o e pirueta) os padr?es discriminados entre essas classes. Tais comportamentos podem ser usados como par?metros para identificar altera??es comportamentais, bem como os padr?es de atividade di?ria e sazonais. Desta forma, o presente estudo teve por objetivo caracterizar a frequ?ncia de execu??o de atividades a?reas no decorrer do per?odo em que os golfinhos-rotadores permanecem dentro da Ba?a dos Golfinhos de Fernando de Noronha, bem como verificar a exist?ncia de poss?veis flutua??es hor?rias di?rias e sazonais na exibi??o de tais comportamentos. Para isso, foram analisados dados que compreendem o per?odo entre janeiro de 2006 a dezembro de 2010, totalizando 1.431 dias de observa??o em ponto fixo, sendo registradas 113.027 atividades a?reas, m?dia di?ria de 72,27 (DP=96,10). Nas 5.478 horas e 54 minutos de observa??o, as atividades a?reas horizontais foram observadas em maior frequ?ncia, sendo a rota??o o padr?o mais executado. Maior frequ?ncia de execu??o das atividades a?reas foi observada em indiv?duos adultos, mas tanto para adultos quanto para filhotes, observou-se predom?nio das atividades horizontais, com a rota??o sendo o padr?o mais executado. Correla??o positiva foi observada entre a quantidade de atividades a?reas executadas e o n?mero de animais dentro da Ba?a. Flutua??o hor?ria di?ria foi observada na express?o das atividades a?reas pelos golfinhos-rotadores, sendo observado maior pico de atividade no hor?rio entre 8h e 8h59min, tanto para a frequ?ncia relativa total de atividades a?reas, quanto para as classes e os padr?es. Diferen?as entre as esta??es clim?ticas seca e chuvosa foram observadas, com maior registro de atividade a?rea durante o per?odo de chuvas. Entretanto, o perfil de distribui??o da frequ?ncia relativa de atividades a?reas se assemelha para ambas as esta??es, mantendo o hor?rio de maior pico de atividade. Quando discriminadas as atividades a?reas nas classes e nos padr?es considerados, para ambas as esta??es observaram-se padr?o de flutua??o hor?ria semelhante; para a maioria dos par?metros analisados, maior frequ?ncia relativa de execu??o das atividades a?reas se mant?m entre 8h e 8h59min
75

Identificação e análise das áreas domicilares do boto-cinza, Sotalia guianensis (Van Bénéden, 1864), no estuário de Cananéia, São Paulo

Oshima, Júlia Emi de Faria [UNESP] 11 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-11Bitstream added on 2014-06-13T21:00:36Z : No. of bitstreams: 1 oshima_jef_me_rcla.pdf: 1892758 bytes, checksum: 3919835a6c437affa1473ba3868d166b (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O conceito de área domiciliar, ou home range, foi definido como “a área utilizada por um indivíduo em suas atividades normais de forrageamento, reprodução e cuidado da prole”. O estudo sobre o uso de área pode fornecer informações sobre padrões de reprodução, organização e interações sociais, recursos limitantes e componentes importantes do habitat. É escasso o conhecimento sobre as características relacionadas à forma com que o boto-cinza, Sotalia guianensis (Van Bénéden, 1864) (Cetacea, Delphinidae), usa seu habitat. O objetivo deste estudo foi identificar e analisar as áreas domiciliares de S. guianensis no estuário de Cananéia (~2503‟S; 47o55‟W), litoral sul de São Paulo. Os esforços para coleta de dados foram realizados entre os anos de 2000 e 2010 com o uso da técnica de foto-identificação. A referida técnica permite aos investigadores identificar indivíduos de uma população ao longo do tempo e do espaço. De 135.918 fotografias batidas, 34.086 (25%) foram consideradas úteis para identificações individuais. Duzentos e cinco indivíduos foram catalogados através das marcas identificadas em suas nadadeiras dorsais. Utilizando os pontos de localização dos indivíduos identificados foi possível estimar o tamanho das áreas domiciliares de 31 indivíduos que apresentaram 20 ou mais avistagens em dias distintos. Quatro métodos foram testados com a extensão Home Range Tools para o ArcGIS 9.2 para analisar e comparar as áreas domiciliares estimadas: Mínimo polígono convexo (MPC), kernel adaptativo com validação cruzada de quadrados mínimos (LSCV), kernel fixo com largura de referência (href) e kernel fixo com LSCV / The concept of home range was described elsewhere as “the area traversed by the individual in its normal activities of food gathering, mating and caring of young”. Home range studies provide significant insights on mating patterns, social organization and interactions, limiting resources and important components of the habitat. Knowledge about habitat use by Guiana dolphins, Sotalia guianensis (Van Bénéden, 1864) (Cetacea, Delphinidae), is still scarce. The aim of this study was to identify and analyze homes ranges of Guiana dolphins in the Cananéia estuary (~2503‟S; 47o55‟W), southern São Paulo state. Photo-identification efforts were conducted between 2000 and 2010. This technique allows investigators to identify individuals in a population through time and space. From a total 135,918 pictures taken, 34,086 (25%) were good quality pictures useful for individual identification. Two hundred and five individuals were catalogued based on permanent notches in their dorsal fins. Using the locations of the identified individuals, it was possible to estimate home range sizes of 31 individuals which had 20 or more sightings in distinct days. Four methods were tested with the Home Range Tools extension for ArcGIS 9.2, to analyze and compare the estimated home ranges: minimum convex polygon (MCP), adaptative kernel with least squares crossvalidation (LSCV), fixed kernel with reference bandwidth (href) and fixed kernel with LSCV
76

The reproduction biology of four species of South African dolphins

Reddy, Kasturi January 1996 (has links)
Seasonality of reproduction in common dolphins (Delphinus delphis), bottlenosed dolphins (Tursiops aduncus), striped dolphins (Stenella coeruleoalba) and humpbacked dolphins (Sousa chinensis) was examined using standard light microscope techniques. In the males four stages of testicular development could be identified. Individuals less than 2.26m in length and 105kg in mass had testes that contained small seminiferous tubules (0.048mm ± O.Olmm in diameter) and were classified either as juveniles (gonocytes present) or inactive (no gonocytes). Adults whose testes contained spermatozoa were said to be in late spermatogenesis while those whose testes contained no spermatids or spermatozoa were referred to as being in early spermatogenesis. In the males of D. delphis, T. aduncus and S. chinensis, late spermatogenesis occurred throughout the year and there was no significant difference in the monthly mean seminiferous tubule diameters (p > 0.05) within species. I conclude therefore that in these three species spermatogenesis is aseasonal. No conclusions about seasonality of spermatogenesis could be made for S. coeruleoalba owing to the small sample size. Large Graafian follicles occurred in the ovaries of all four species in most months of the year. However, the presence of Graafian follicles can not be taken as an indication of timing of reproduction since they may be remnants of follicles that have not yet degenerated. In D. delphis, T. aduncus and S. coeruleoalba luteal bodies (corpora albicans or corpora lutea) occurred in most months of the year. Active corpora lutea will be present in all months, in some members of the population, since gestation is approximately 12 months. The sperm structure of D. delphis was examined by scanning electron microscopy. The sperm of D. delphis is essentially similar to that described for two other species of Cetacea (Physeter catodon and Tursiops aduncus), having an ellipsoidally shaped head and a short mid-piece with nine mitochondria. The sperm dimensions for D. delphis were head length, 4.4pm; head width, 2.0pm and mid-piece length, 2.4pm. An analysis of foetal age in D. delphis showed that the majority of the foetuses were conceived in January with birth occurring the following summer (December), suggesting that reproduction is seasonal. Neonates of T. aduncus were found throughout the year suggesting aseasonal reproduction. Foetal material was not available for S. coeruleoalba and S. chinensis. Seasonality of reproduction in the four species of dolphins studied has been discussed in relation to feeding, migration and worldwide distribution of the species.
77

Evaluation of live fish as an echolocation enrichment for the bottlenose dolphin (Tursiops truncatus)

Karczmarz, Veronika January 2016 (has links)
Bottlenose dolphins (Tursiops truncatus) kept in zoos and dolphinarias rarely get an outlet for their echolocation abilities as their pool environment is often quite barren. Not much research has been carried out on enrichments promoting echolocation for dolphins in human care. In the present study a setup with live fish was compared to a setup with air-filled floats (providing strong sonar targets, similar to the swim bladders of large fish) and a control setup. A PCL (porpoise click logger) was used to record the echolocation click trains produced by the dolphins and aimed at the three setups. Behavioural data was also collected from video footage. Both the PCL data and all the behavioural observations indicated that the fish setup was more interesting than the float and the control setup, for the dolphins to echolocate towards. However, there were some contradictions with some parameters, where the floats and control seemed to be more interesting. This was probably due to the location of the PCL hydrophone in relation to the floats and fish, and not because the dolphins had a real bigger interest in these setups. To increase the possibility for dolphins to perform more echolocation in human care and increase their welfare, live fish can be recommended as echolocation enrichment.
78

The distribution, movements and abundance of Heaviside's dolphins in the nearshore waters of the Western Cape, South Africa

Elwen, Simon Harvey 06 January 2009 (has links)
Heaviside's dolphin (Cephalorhynchus heavisidii) is a poorly studied coastal delphinid with a limited inshore distribution off the west coast of southern Africa where it is sympatric with the similar sized dusky dolphin (Lagenorhynchus obscurus). It is exposed to an unknown level of bycatch particularly in near-shore set-net fisheries and is also potentially impacted by the growing boat-based whale watching industry in South Africa. In this thesis I describe the results of a study investigating the distribution, movements, behaviour and abundance of Heaviside's dolphins in the near-shore environment of the Western Cape of South Africa as a precursor to assessing its potential vulnerability to anthropogenic threats. Data were gathered using three different approaches in the field; diurnal shore based observations, boat based photo-ID surveys along ~390 km of coastline and satellite telemetry. Data were collected for dusky dolphins where feasible. Heaviside’s dolphins exhibited a strong pattern of resting inshore during daytime and foraging offshore at night that was presumed to be related to the movement of juvenile hake (Merluccius capensis) closer to the surface at night. In addition, despite near-shore observations failing to indicate feeding, dolphins were consistently found to be more abundant along regions of the coast which over the long term had higher levels of small hake available offshore. In contrast the near-shore distribution of dusky dolphins varied considerably between years possibly due to the very near-shore environment being at the edge of their habitat. A tendency for dusky dolphins to move offshore during upwelling conditions was observed from shore in St Helena Bay, the site of a strong predictable upwelling cell. However this was the only location in which very large groups of animals (50-500) were seen during coastal boat surveys suggesting this pattern may have been area specific and feeding strategies may vary throughout their range. Sympatric appears to be mediated by differences in overall range and prey type and size differentiation. Heaviside’s dolphins were found to have small home ranges and show a high degree of site fidelity over several years, at least during summer months. Dolphins fitted with satellitelinked transmitters used only limited home ranges (~876 to 1990 km2) which scaled positively with body size within the ~50 day tracking period, while photographically identified animals did not disperse significantly further than this over 3 years. The maximum coastwise displacement observed for an individual (88.4 km after 1 year) was considerably less than the 390 km length of the overall study area, and equivalent to the maximum coastwise movement seen during satellite-tagging (83.1 km). This suggests that measured home ranges may be stable over several years, although the number of resighted individuals (n = 76) was small and (as data collection was restricted to summer months) seasonal differences in movements or migrations cannot be ruled out. Associations among photographically identified animals did not differ from a random mixing of individuals, suggesting that this species has a fission-fusion type social structure at least over the short term. The abundance of Heaviside's dolphins was calculated from photo-ID mark-recapture data at three spatial scales using Chapman’s modified Petersen estimators. The proportion ofdistinctively marked individuals in this species is low (14 - 17%) reducing sample sizes and introducing a large extrapolation factor, both of which contribute to an increase in the variance of any resultant population estimate. Using resightings after one year, the total number of animals over the whole 390km study area was calculated to be 6345 (CV = 0.26, CI = 3573 – 11 267) while using same-season re-sightings the total number of animals using a 20km long section of coastline in the centre of the study area was calculated as 527 (CV = 0.35, CI = 272 – 1020). These estimates may be significantly biased downwards by the effects of heterogeneity in the capture probability of individuals which it was not possible to account for analytically due to small sample sizes. Sympatry of Heaviside's and dusky dolphins appears to be mediated by differences in the overall range and in the type and size of prey consumed. From a conservation point of view, our findings for Heaviside's dolphins are encouraging in that they indicate a relatively large population size, although their strong site fidelity does make them more vulnerable to localised impacts than a more widely ranging species like dusky dolphins and this needs to be considered during management of the population. / Thesis (PhD)--University of Pretoria, 2009. / Zoology and Entomology / unrestricted
79

Effects and added drag on cetaceans : fishing gear entanglement and external tag

Van der Hoop, Julie M January 2017 (has links)
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. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 283-314). / 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. / by Julie M. van der Hoop. / Ph. D.
80

Lost and Found : Activating forgotten space and knowledge

Jonasson, Rasmus January 2022 (has links)
The project proposes the production of devices to enhance the value or experience of a place as well as to allow research and education in history, collective memory and contemporary times of the city that we live in. Looking at the city through a specific type of architecture, concept or material, and hopefully giving an honest perspective of the space we inhabit. For this project the topic was contemporary ruins and their structural and visual values. Cataloging the timber barn, exploring it in an industrial hall and then exhibiting them on the concrete dolphins in the river, all buildings or structures created purely for convenience but have since lost all or some of this convenience, therefore becoming contemporary ruins. In the end creating structures with the purpose of learning, exhibiting them for others to learn as well; and in the end finding a place and purpose for the structure. Turning the building from a research project into a folly and then into a device for experience. Producing with the goal of learning, placing with the goal of enhancing, without designing specifically for the end product but rather for the process itself.

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