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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.
1

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 /

Gibb, Giselle Renee. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 90-108). Also available on the World Wide Web.
2

Using stable isotopes to assess population structure and feeding ecology of North Pacific humpback whales (Megaptera novaeangliae)

Witteveen, Briana Harmony. January 2008 (has links)
Thesis (Ph.D.)--University of Central Florida, 2008. / Adviser: Graham A. J. Worthy. Includes bibliographical references.
3

Behavioral choices of male humpback whales (Megaptera novaeangliae) on the Hawaiʻian wintering grounds

Hakala, Siri January 2004 (has links)
Thesis (M.A.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 64-68). / vi, 68 leaves, bound ill. 29 cm
4

Structure and dynamics of the Gulf of Maine humpback whale population/

Robbins, Julie. January 2007 (has links)
Thesis (Ph.D.) - University of St Andrews, May 2007.
5

Dietary patterns of humpback whales (Megaptera novaeangliae) in the Northwest Atlantic : evidence from 13C and 15N stable isotopes /

Todd, Sean Kevin, January 1997 (has links)
Thesis (Ph. D.), Memorial University of Newfoundland, 1998. / Bibliography: leaves 149-175.
6

Maternal behaviour of humpback whales in southeast Alaska

Szabo, Andrew Ronald. 10 April 2008 (has links)
In this study, I characterize the maternal care patterns of humpback whales in southeast Alaska. Through a study of proximity behaviour, I show that humpbacks behave similarly to terrestrial ungulate 'followers': the cow and calf are rarely more than several body lengths apart; proximity between the cow and calf is greatest during periods of travel relative to other behaviours; and, proximity is greatest when the dive behaviour of the pair is synchronized. Unlike that observed in typical follower species, however, proximity is not found to decrease significantly as the pair's association lengthens. To account for this, I argue that the length of the observation period was insufficient to detect such a trend since maternal pairs remain together for several months after the last observations. In addition, I analyze the diving behaviour of the maternal pair to examine the potential negative consequences for the female associated with the follower tactic in humpbacks. The results suggest that several behavioural modifications are made by the cow and calf in an effort to minimize the duration of separation between the two. Ultimately, I argue that behaviour observed in humpback whales is commensurate in function with following behaviour in terrestrial ungulate followers. Humpbacks are migratory, and as in many migratory species, following behaviour provides a mechanism whereby the maternal dyad can maintain close proximity during periods of travel. Moreover, as with many follower species, humpbacks can rely upon their large size as a means of defence against offspring predation. Finally, although obvious differences exist between the habitats in which humpbacks and ungulate followers reside, arguably both are open habitats that lack the cover necessary to allow for offspring concealment.
7

The Effect of Humpback Whale-Like Protuberances on Hydrofoil Performance

Custodio, Derrick 26 April 2012 (has links)
The humpback whale is very maneuverable despite its enormous size and rigid body. This agility has been attributed to the use of its pectoral flippers, along the leading edge of which protuberances are present. The leading edge protuberances are considered by some biologists to be a form of passive flow control and/or drag reduction. Force and moment measurements along with qualitative and quantitative flow visualizations were carried out in water tunnel experiments on full-span and finite-span hydrofoil models with several different planforms and protuberance geometries. A NACA 634-021 cross-sectional airfoil profile was used for the baseline foil in all tests. Four planform geometries chosen included: a full-span set of foils which spanned the breadth of the water tunnel, a finite-span rectangular planform, a finite-span swept hydrofoil, and a scale flipper model that resembled the morphology of the humpback whale flipper. A variety of sinusoidal protuberance geometries which included three amplitudes equal to 2.5%, 5%, and 12% and wavelengths of 25% and 50% of the local chord were examined in combination with the different planform geometries. Testing included force and moment measurements and Particle Image Velocimetry (PIV) to examine the load characteristics and flow field surrounding the modified foils. Load measurements show that modified foils are capable of generating higher lift than the baseline at high angles of attack while at low angle of attack the baseline generally produces a lift coefficient equal to or greater than the modified cases. With the exception of the modified flipper model, the drag coefficients of the modified hydrofoils are either equal to or greater than their baseline counterparts. The increased drag reduces the lift-to-drag ratio. Flow visualizations show that vortical structures emanating from the shoulders of the protuberances are responsible for increased lift and drag at high angles. Cavitation tests show that modified foils cavitate in pockets behind the troughs of protuberances whereas the baseline foils produce cavitation along the entire foil span. Also, the cavitation numbers on modified hydrofoils were consistently higher than their baseline counterparts. This work shows the effect of leading edge protuberances on the aforementioned performance characteristics.
8

Songs of a humpback whale (Megaptera novaeangliae) in Taiwan and evolution of communication in cetaceans

Yu, Hsin-Yi 09 September 2002 (has links)
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.
9

Acoustic and visual tracking reveals distribution, song variability and social roles of humpback whales in Hawaiian waters

Frankel, Adam S January 1994 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1994. / Includes bibliographical references (leaves 128-141). / Microfiche. / xi, 140 p. ill. 29 cm
10

The development and application of computational multi-agent models for investigating the cultural transmission and cultural evolution of humpback whale song

Mcloughlin, Michael January 2018 (has links)
Three different multi-agent models are presented in this thesis, each with a different goal. The first model investigates the possible role migratory routes may have on song evolution and revolution. The second model investigates what social networks could theoretically facilitate song sharing in a population of whales. The third model implements a formal grammar algorithm in order to investigate how the hierarchal structure of the song may affect song evolution. Finally, the thesis attempts to reconnect the models with their origins and discusses how these models could potentially be adapted for composing music. Through the development of these different models, a number of findings are highlighted. The first model reveals that feeding ground sizes may be key locations where song learning from other population may be facilitated. The second model shows that small world social networks facilitate a high degree of agents converging on a single song, similar to what is observed in wild populations. The final model shows that the ability to recognise hierarchy in a sequence coupled with simple production errors, can lead to songs gradually changing over the course of time, while still retaining their hierarchal structure.

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