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An assessment of the habitat quality and nutritional intake of North Atlantic right whales in Cape Cod Bay /Delorenzo, Amy Susanna. January 2005 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2005. / Typescript. Includes bibliographical references (leaves 216-229).
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Investigating the migration and foraging ecology of North Atlantic right whales with stable isotope geochemistry of baleen and zooplanktonLysiak, Nadine Stewart J. January 2008 (has links) (PDF)
These (Ph.D.)--Boston University, 2008. / Title from PDF title page. Available through UMI ProQuest Digital Dissertations. Includes bibliographical references (leaves 178-194). Also issued in print.
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Integrating genetic and photo-identification data to assess reproductive success in the North Atlantic right whale (Eubalaena glacialis) /Frasier, Timothy Ray. White, Bradley Neil. January 2005 (has links)
Thesis (Ph.D.)--McMaster University, 2005. / Advisor: Bradley N. White. Includes bibliographical references (p. 145-165). Also available online.
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Lipid metabolism by right whales using fecal samples to assess assimilation of copepod triacylglycerols and wax esters /Swaim, Zachary Taylor. January 2008 (has links) (PDF)
Thesis (M.S.)---University of North Carolina Wilmington, 2008. / Title from PDF title page (viewed September 22, 2008) Includes bibliographical references (p. 45-50)
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Visual health assessment of parous female southern right whales (Eubalaena australis) off the southern Cape coast, South AfricaHörbst, Sandra 13 March 2020 (has links)
The long-term monitoring of the South African southern right whale population has revealed a decrease in sightings along the coast and an increase of calving intervals within the last few years, causing changes in the species´ demographics causing a decrease in annual population growth rate (6.5% y -1 ). Because reproductive success is linked to body condition, the purpose of this study was to conduct a visual health assessment based on overhead photographs from the annual aerial southern right whale surveys and detect potential links between visual health condition of parous females and the increased calving intervals. Additionally, it was aimed to find relationships between visual health of parous females and environmental indices of the Southern Ocean, representing food availability. To allow global comparison of the results, the method used for the visual health assessment was developed in collaboration with international southern right whale researchers from Australia and South Africa. The health indices were adapted from a visual health assessment method developed for northern right whales and include body condition, skin condition, the presence of cyamids around the blowholes and rake marks on the skin. The results showed that these health variables derived from overhead photographs were sufficient to detect visual health changes over time. Within the study period (2005 – 2017), there were two years in which whales had a significant decreased visual health (i.e. increased health score) than average; 2008 and 2014. No direct link between the observed health condition and calving intervals could be found, possibly due to the lack of data on calving intervals post-2014 as well asthe assessment of breeding females only (i.e. breeding females are in good enough conditions to reproduce). However, significant relationships were found between visual health and Southern Ocean productivity (p< 0.001) and climate indices (p < 0.05) with a 0-year lag. These results clearly indicate a link between southern right whale visual health condition and Southern Ocean food availability in one feeding ground, suggesting that this may be the primary feeding ground for parous females during pregnancy. Understanding the links between visual health, reproductive success and climate/food availability helps to understand changes in the population’s demographics and to predict the resilience of the species. Additionally, the standardization of the method allows for global comparison.
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Animal Movement in Pelagic Ecosystems: from Communities to IndividualsSchick, Robert Schilling January 2009 (has links)
<p>Infusing models for animal movement with more behavioral realism has been a goal of movement ecologists for several years. As ecologists have begun to collect more and more data on animal distribution and abundance, a clear need has arisen for more sophisticated analysis. Such analysis could include more realistic movement behavior, more information on the organism-environment interaction, and more ways to separate observation error from process error. Because landscape ecologists and behavioral ecologists typically study these same themes at very different scales, it has been proposed that their union could be productive for all (Lima and Zollner, 1996). </p><p>By understanding how animals interact with their land- and seascapes, we can better understand how species partition up resources are large spatial scales. Accordingly I begin this dissertation with a large spatial scale analysis of distribution data for marine mammals from Nova Scotia through the Gulf of Mexico. I analyzed these data in three separate regions, and in the two data-rich regions, find compelling separation between the different communities. In the northernmost region, this separation is broadly along diet based partitions. This research provides a baseline for future study of marine mammal systems, and more importantly highlights several gaps in current data collections.</p><p>In the last 6 years several movement ecologists have begun to imbue sophisticated statistical analyses with increasing amounts of movement behavior. This has changed the way movement ecologists think about movement data and movement processes. In this dissertation I focus my research on continuing this trend. I reviewed the state of movement modeling and then proposed a new Bayesian movement model that builds on three questions of: behavior; organism-environment interaction; and process-based inference with noisy data.</p><p>Application of this model to two different datasets, migrating right whales in the NW Atlantic, and foraging monk seals in the Northwest Hawaiian Islands, provides for the first time estimates of how moving animals make choices about the suitability of patches within their perceptual range. By estimating parameters governing this suitability I provide right whale managers a clear depiction of the gaps in their protection in this vulnerable and understudied migratory corridor. For monk seals I provide a behaviorally based view into how animals in different colonies and age and sex groups move throughout their range. This information is crucial for managers who translocate individuals to new habitat as it provides them a quantitative glimpse of how members of certain groups perceive their landscape.</p><p>This model provides critical information about the behaviorally based movement choices animals make. Results can be used to understand the ecology of these patterns, and can be used to help inform conservation actions. Finally this modeling framework provides a way to unite fields of movement ecology and graph theory.</p> / Dissertation
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The seasonal movements and dynamics of migrating humpback whales off the east coast of AfricaBanks, Aaron M. January 2013 (has links)
Data collected during boat-based and aerial surveys were used to describe population structure, movements, temporal patterns of migration and skin condition of humpback whales in breeding sub-stock C1-S off southern Africa. Results confirmed that the migration route along the south coast of South Africa is linked to the winter ground off Mozambique. A lack of exchange between breeding sub-stocks C1-N and C1-S was found, suggesting that these are independent of each other. Molecular analysis revealed unexpected levels of population structure between the migration route and the winter ground of C1-S, as well as the possibility that this migration route is also utilised by some individuals from breeding sub-stock C3. A skin condition of unknown aetiology that primarily affects humpback whale mother-calf pairs was identified. The first assessment of its prevalence and severity was made, providing a baseline for future monitoring. Humpback whale abundance in an inshore region of Bazaruto Archipelago, Mozambique was estimated and attempts were also made to use the limited information off Plettenberg Bay/Knysna, South Africa. In addition to improving our understanding of humpback whales from Breeding Stock C, knowledge about another baleen whale species utilising the southwest Indian Ocean was extended. The first evidence of southern right whale presence off the coast of Mozambique since the cessation of whaling was documented. It remains unknown whether this is a remnant sub-stock or the recovering South African sub-stock reoccupying its historical range.
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