Texte remanié de: Diss.--Boston university. / Bibliogr. p. 221-228. Index.

Not available / text

Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Felipe Voloch. Vita. Includes bibliographical references. Also available from UMI.

The aim of this study was to investigate various aspects of the life history of white sharks Carcharodon carcharias at Dyer Island, South Africa, between August 1999 and January 2001. Inter-specific predatory interactions between the white shark and various potential prey species such as the Cape fur seal (Arctocephalus pusillus pusillus), African penguin (Spheniscus demersus), Cape cormorant (Phalacrocorax capensis), bank cormorant (P. neglectus), crown cormorant (P. coronatus) and white-breasted cormorant. (P. carbo) were observed. White sharks were attracted daily to a research vessel positioned at various anchorages in the vicinity of Dyer Island. Spatial and temporal abundance, and population composition of white sharks were recorded throughout the year and revealed seasonal trends in habitat utilisation. White sharks occupied inshore waters, away from the Geyser Rock seal colony in the summer. Sharks became abundant in the near vicinity of Geyser Rock in the winter period. The summer inshore population was characterised by the increased total length of sharks and the exclusive presence of female sharks. Prey resembling decoys were used to investigate trends in the 'predatory motivation' of white sharks in relation to various independent variables. White sharks displayed greatest predatory motivation in close proximity to a seal colony, in overcast conditions, and when water clarity was low. White sharks evidently elevate their motivation to hunt large prey, which are difficult to catch, in situations where the likelihood of encountering valued prey and completing a successful attack is greatest. Ontogenetic difference in predatory motivation towards the decoys existed, with sharks above 325 cm TL displaying greater predatory motivation than smaller sharks. Various choice tests were conducted to determine the visual discriminatory ability and prey preference of white sharks at Dyer Island. The results suggested that white sharks preferred a biologically familiar shape (pinniped) over an inanimate shape (rectangle), smaller (75 mm TL pinniped) over larger (1800 mm TL pinniped) prey, and a pinniped decoy over a penguin decoy of similar size. Selectivity in larger white sharks (>375 cm TL) was most noticeable in the prey shape (pinniped vs. rectangle) experiment, which suggests they may readily utilise a speculative hunting strategy based on rough similarities between detected potential prey and recognised prey. In this situation mistaken identification of prey is more possible. Smaller white sharks (a majority of the sample) displayed most selectivity in the prey size experiment, with strong preference for the smaller seal decoy over the large one. This pattern indicates that prey size may be a partial limiting factor in the feeding of smaller white sharks. Negative impacts (such as conditioning or distraction) of cage-diving on white sharks were assessed by the measurement of white shark contact time and visit time in relation to the chumming vessel. These results revealed that smaller sharks had longest visit times, and that sharks in the vicinity of Geyser Rock displayed visitation patterns indicative of hunting sharks. Particular vigilance should be kept by operators not to allow small sharks to take bait (reward). The channel area appears to be an important hunting ground and white shark cage-diving should perhaps be restricted in this area. White sharks also showed greater activity around the chumming vessel on cloudy days and operators must be particularly vigilant to deny sharks any rewards (bait) under these conditions. Both the white sharks and Cape fur seals predate and/or attack seabirds and predatory interactions were quantified and qualified by the routine collection and inspection of seabird carcasses and injured birds, as well as opportunistic observations of live attacks throughout this study. White sharks are infrequent predators of seabirds in this ecosystem, perhaps due to an abundance of Cape fur seals (a preferred prey), anti¬predator behaviour by penguins, and seabirds not being a sought after prey type. Cape fur seals were a more conspicuous seabird predator, annually attacking a significant percentage of the adult penguin (1.99-2.52%), white-breasted cormorant (5.21-5.72%), and crowned cormorant (3.13%) populations. A minimum estimate of 1.09% of the fledgling Cape cormorant population also succumbed to Cape fur seal predation. / Dissertation (MSc(Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted

Master of Science / Department of Geology / Charles G. Oviatt / The Dyer Mountain quadrangle, located in Utah approximately 200 km east of Salt Lake City and 20 km north of Vernal, lies on the south flank of the east-west trending Uinta anticline. The topography of the area varies from mountain peaks to deep canyons, with rolling hills of uplands in between. The elevation in the quadrangle ranges from 3124 m (10248 ft) at the top of Dyer Mountain to 1835 m (6020 ft) at the lowest point of Big Brush Creek. Most of the northern portion of the quadrangle is vegetated by aspens and pines, whereas the southern part of the quadrangle is covered with sagebrush and grasses. Due to its location on the anticline, the quadrangle contains bedrock that dips gently to the south and southeast. The ages of the rocks within the quadrangle range from the Precambrian Uinta Mountain Group to the Quaternary and Tertiary gravels. Also present are the following formations: Cambrian Lodore; Mississippian Madison, Doughnut, and Humbug; Pennsylvanian Round Valley and Morgan; Pennsylvanian to Permian Weber; Permian Meade Peak Member of the Phosphoria and Franson Member of the Park City; and various Quaternary sediments. The Lodore Formation and the Madison Limestone rest on major unconformities, and the Quaternary and Tertiary gravels overlie the Gilbert Peak erosion surface. The Uinta anticline and southerly dip of the Proterozoic and Paleozoic rocks are a result of Late Cretaceous uplift during the Laramide orogeny; Tertiary rocks within the area show little to no deformation. Limestone and various types of ores have been mined in the quadrangle, and phosphorous is currently being mined for fertilizer production. Several landslides, common at the juncture of the Quaternary and Tertiary gravels and Permian shales, were identified within the quadrangle. An anticline and syncline, trending northwest to southeast, lie in the southeast portion of the quadrangle and transect Big Brush Gorge. Geologic hazards of the area include landslides, erosion and failure of road grades, and cliffs near trails. The karst topography of the area presents dangers of sink holes, and evidence of ceiling collapse is present within Big Brush Cave, a popular destination for tourists and cavers.

This report offers an analysis of the ways in which two eighteenth century georgic poems, John Dyer’s The Fleece and William Cowper’s The Task, mediate evangelical and imperial practices. Through an inquiry into the recent critical intersection between Kevis Goodman’s media focused research into the georgic and Clifford Siskin and William Warner’s similarly inflected inquiry into the Enlightenment, this report suggests that the didactic, agricultural musings of Dyer and Cowper betray a deep engagement the consequences of imperialism and the execution of Britain’s dawning evangelical charge. / text

Thesis (Ph. D.)--University of Washington, 1993. / Vita. Includes bibliographical references (leaves [131]-137).

Thesis (Ph. D.)--Yale University, 1931. / Without thesis note. "Poems": p. 175-201.

Thesis (M.A.)--University of Wisconsin--Madison, 1966. / Includes bibliographical references.

Thesis (M.A.)--University of Wisconsin--Madison, 1966. / Title from title screen (viewed Oct. 1, 2007). Includes bibliographical references. Online version of the print original.