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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.
491

The commercial and recreational marine skiboat linefisheries in Richards Bay, KwaZulu-Natal.

January 2005 (has links)
In order to assess and improve their management, a survey of the commercial and recreational marine linefisheries in Richards Bay was conducted from June 2002 to July 2004. The ultimate aim of this survey was to develop a sound management framework for the commercial and recreational marine Iinefisheries in Richards Bay. Skippers on both commercial and recreational skiboats were all white males in their mid-40s whom were fairly experienced. There were twice as many crew on commercial than recreational skiboats. The crew on commercial skiboats were mostly black males while on recreational skiboats, crew were mostly white males. Slinger was the most important species caught by commercial fishermen off Richards Bay, accounting for the vast majority of catches by number and mass. The total contribution by sparids to commercial catches amounts to approximately 93 % by number and 81 % by mass. Recreational catches comprised a greater variety of species (73 recreational species versus 54 commercial species), signifying a less focussed targeting approach compared to commercial skiboat fishermen. Although slinger also numerically dominated recreational linefish catches, catface rockcod were most important by mass. Although there were five times more recreational outings during the study, total catch by commercial skiboat fishermen was five times higher than that of recreational fishermen. This was expected, as the average duration of each commercial outing is more than twice that of recreational outings and the crew numbers are higher. Commercial skiboat fishermen in Richards Bay are also more effective, as the average number of fish caught per man per hour on commercial skiboats was approximately 4 times greater than that on recreational skiboats. Total estimated catch for the commercial sector was 28 tonnes and 173 tonnes for the recreational sector. Comparison of data between this survey and commercial data available on NMLS showed similar species composition, although the dominance of slinger was 20 % higher in this survey compared to data. Similarly, within the recreational sector, there was a close similarity in catch composition between this survey and that catch inspections. The profit (excluding the costs of fixed assets) that each commercial fisherman earns per month was estimated to be in the region ofR8 500. However, if one examines the value of the commercial linefishery as a whole, it appears that there is a net loss of R90 000 per year, excluding the costs of fixed assets. The discrepancy stems from the disparity between the recorded number of launches and the number reported by skippers. Most of the commercially caught fish are not sold in Richards Bay, but are exported to Gauteng. The average monthly Iinefish catch by commercial fishermen was less than half the average estimated consumption of Iinefish in Richards Bay, and the difference appears to be made up from recreational catches, with many consumers indicating that they either caught their own fish or were given it. Knowledge of and compliance with fishing regulations by commercial and recreational skiboat fishermen in Richards Bay was reasonably good. The main recommendations emanating from this study include continuous monitoring of the Richards Bay commercial and recreational line fishery in order to determine the efficacy of the new regulations, the development of area-based commercial linefishing permits and the possible introduction of restrictions on the sale of fish outside of the Richards Bay area. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2005.
492

Variability, change and continuity in social-ecological systems: insights from James Bay Cree cultural ecology

Peloquin, Claude 04 February 2008 (has links)
This thesis looks at how the Cree people of Wemindji, James Bay, Québec, understand and live with ecological complexity and dynamism. The focus is on the interplay between variability, change, and continuity in the Canada goose (Branta canadensis) hunt. Looking at Cree goose-hunting in the light of cultural ecology and resilience thinking, the research suggests that Cree hunters are attentive and responsive to ecological fluctuations, fine-tuning local arrangements to local environmental conditions. Ecological variability and unpredictability, such as weather, goose population dynamics and migration patterns, are mediated by local management strategies in which goose hunting areas shift in space and time. However, whereas these strategies are still practiced nowadays, they are (to some extent) overwhelmed by changes occurring at larger scales. Some of these are related to climate change and anthropogenic disturbances; others are related to social-cultural changes that influence resource-use patterns. I discuss how these different drivers interact among themselves and impact the goose-hunt, and how the Wemindji Cree respond to these changes.
493

unplanned wanderings: and the discovery of a pier

Williamson, Micheal 15 September 2008 (has links)
My question here revolves around my orientation with my own work; my own frustrations and inability to so often answer the question “can a meaningful place be designed?” This journey examines the theory of semiotics. Through this, three strategies have been developed to explore the branches of semiotic research in Landscape Architecture. The first strategy allows meaning to develop through time, and it is with the repeated usage of people that meaning will accrue. The second strategy shows how meaning can be determined before the design through mapping current and desired locations of meaning in space. And, the third strategy reflects on how meaning emerges from the earth when no interference from designers or users occurs. The result of the three individual strategies is a combination of solutions, illustrating how to create places of true richness. This new space will engage visitors, pull in new visitors, and help create something memorable for those engaging in a space.
494

Beluga whale, Delphinapterus leucas, vocalizations and their relation to behaviour in the Churchill River, Manitoba, Canada

Chmelnitsky, Elly 13 September 2010 (has links)
The investigation of a species’ repertoire and the contexts in which different calls are used is central to understanding vocal communication among animals. Beluga whale, Delphinapterus leucas, calls were classified and described in association with behaviours, from recordings collected in the Churchill River, Manitoba, during the summers of 2006-2008. Calls were subjectively classified based on sound and visual analysis into whistles (64.2% of total calls; 22 call types), pulsed or noisy calls (25.9%; 15 call types), and combined calls (9.9%; seven types). A hierarchical cluster analysis, using six call measurements as variables, separated whistles into 12 groups and results were compared to subjective classification. Beluga calls associated with social interactions, travelling, feeding, and interactions with the boat were described. Call type percentages, relative proportions of different whistle contours (shapes), average frequency, and call duration varied with behaviour. Generally, higher percentages of whistles, more broadband pulsed and noisy calls, and shorter calls (<0.49s) were produced during behaviours associated with higher levels of activity and/or apparent arousal. Information on call types, call characteristics, and behavioural context of calls can be used for automated detection and classification methods and in future studies on call meaning and function.
495

Variability, change and continuity in social-ecological systems: insights from James Bay Cree cultural ecology

Peloquin, Claude 04 February 2008 (has links)
This thesis looks at how the Cree people of Wemindji, James Bay, Québec, understand and live with ecological complexity and dynamism. The focus is on the interplay between variability, change, and continuity in the Canada goose (Branta canadensis) hunt. Looking at Cree goose-hunting in the light of cultural ecology and resilience thinking, the research suggests that Cree hunters are attentive and responsive to ecological fluctuations, fine-tuning local arrangements to local environmental conditions. Ecological variability and unpredictability, such as weather, goose population dynamics and migration patterns, are mediated by local management strategies in which goose hunting areas shift in space and time. However, whereas these strategies are still practiced nowadays, they are (to some extent) overwhelmed by changes occurring at larger scales. Some of these are related to climate change and anthropogenic disturbances; others are related to social-cultural changes that influence resource-use patterns. I discuss how these different drivers interact among themselves and impact the goose-hunt, and how the Wemindji Cree respond to these changes.
496

unplanned wanderings: and the discovery of a pier

Williamson, Micheal 15 September 2008 (has links)
My question here revolves around my orientation with my own work; my own frustrations and inability to so often answer the question “can a meaningful place be designed?” This journey examines the theory of semiotics. Through this, three strategies have been developed to explore the branches of semiotic research in Landscape Architecture. The first strategy allows meaning to develop through time, and it is with the repeated usage of people that meaning will accrue. The second strategy shows how meaning can be determined before the design through mapping current and desired locations of meaning in space. And, the third strategy reflects on how meaning emerges from the earth when no interference from designers or users occurs. The result of the three individual strategies is a combination of solutions, illustrating how to create places of true richness. This new space will engage visitors, pull in new visitors, and help create something memorable for those engaging in a space.
497

The Role of Colony Size in the Resistance and Tolerance of Scleractinian Corals to Bleaching Caused by Thermal Stress

Charpentier, Bernadette 25 February 2014 (has links)
In 2005 and 2010, high sea surface temperatures caused widespread coral bleaching on Jamaica’s north coast reefs. Three shallow (9m) reef sites were surveyed during each event to quantify the prevalence and intensity of coral bleaching. In October 2005, 29-57% of the colonies surveyed were bleached. By April 2006, 10% of the corals remained pale/partially bleached. Similarly, in October 2010, 23-51% of corals surveyed at the same sites were bleached. By April 2011, 12% of the colonies remained pale/partially bleached. Follow-up surveys revealed low coral mortality following both events, with an overall mean of 4% partial colony mortality across all species and sites observed in April 2006, and 2% in April 2011. Mixed effects models were used to quantify the relationship between colony size and (a) bleaching intensity, and (b) bleaching related mortality among coral species. The bleaching intensity model explained 51% of the variance in the bleaching response observed during the two events. Of this 51%, fixed effects accounted for ~26% of the variance, 17% of which was attributed to species-specific susceptibility to bleaching , 5% to colony size, <1% colony morphology and 4% to the difference in bleaching intensity between the two events. The random factor (site) accounted for the remaining ~25% of the variance. The mortality model explained 16% of the variance in post bleaching mortality with fixed effects, including colony size, morphology and species explaining ~11% of the variance, and the random effect (site) explaining 5%. On average, there was a twofold difference in bleaching intensity between the smallest and the largest size classes. Modelling the relationship between colony level characteristics and site-specific environmental factors on coral species’ susceptibility to thermal stress can shed light on community level responses to future disturbances.
498

Beluga whale, Delphinapterus leucas, vocalizations and their relation to behaviour in the Churchill River, Manitoba, Canada

Chmelnitsky, Elly 13 September 2010 (has links)
The investigation of a species’ repertoire and the contexts in which different calls are used is central to understanding vocal communication among animals. Beluga whale, Delphinapterus leucas, calls were classified and described in association with behaviours, from recordings collected in the Churchill River, Manitoba, during the summers of 2006-2008. Calls were subjectively classified based on sound and visual analysis into whistles (64.2% of total calls; 22 call types), pulsed or noisy calls (25.9%; 15 call types), and combined calls (9.9%; seven types). A hierarchical cluster analysis, using six call measurements as variables, separated whistles into 12 groups and results were compared to subjective classification. Beluga calls associated with social interactions, travelling, feeding, and interactions with the boat were described. Call type percentages, relative proportions of different whistle contours (shapes), average frequency, and call duration varied with behaviour. Generally, higher percentages of whistles, more broadband pulsed and noisy calls, and shorter calls (<0.49s) were produced during behaviours associated with higher levels of activity and/or apparent arousal. Information on call types, call characteristics, and behavioural context of calls can be used for automated detection and classification methods and in future studies on call meaning and function.
499

Seasonal, inter-annual, and spatial variation in ringed seal feeding ecology in Hudson Bay assessed through stable isotope and fatty acid biomarkers

Young, Brent G. 18 February 2013 (has links)
Current trends toward warmer air temperatures and longer ice free seasons in Hudson Bay are expected to cause changes in Arctic marine ecosystem dynamics. Ringed seals (Phoca hispida) will likely experience changes in levels of predation, competition, and prey availability. The purpose of this thesis was to investigate seasonal, inter-annual, and spatial variation in Hudson Bay ringed seal feeding ecology. Fatty acid composition, δ15N, and δ13C varied significantly by season, suggesting seasonal changes in foraging habitat and diet. Spatial differences in ringed seal stable isotope ratios occurred between western and eastern Hudson Bay, and there was a strong relationship between spring air temperature and δ15N. Peak δ15N occurred within a range in spring air temperatures between approximately -5°C and -2°C. I propose that the high δ15N observed in ringed seals within this temperature range is indicative of relatively greater importance of capelin (Mallotus villosus) in the ringed seal diet.
500

Geology of the Mutton Bay Intrusion and surrounding area, North Shore, Gulf of St. Lawrence, Quebec

Davies, Raymond January 1968 (has links)
Geology and structure of 1,000 square miles of granulite-upper amphibolite facies gneisses cut by syn- and late-kinematic intrusions are described. The circular post-kinematic Mutton Bay alkaline syenite (631 m.y.) is divided into three main intrusive groups on the basis of chemistry, mineralogy, and field relations. Differentiation includes gravity settling and flow differentiation, while intrusion involved early stoping and assimilation with late faulting. Depth of the present level below the roof of the intrusion is estimated at 6-8 miles and temperature of crystallization of felspars in the early magmas at greater than 1015°C at less than 500 bars water pressure. Orthoclase inverted to microcline in foliated rocks that intruded as crystal mushes. A giant gabbro dyke with syenite differentiate (470 m.y.) is intruded by diabase and trachyte dykes. Carbonate enrichment in the trachytes is accompanied by high potash felspar content. Sandstone dykes are the only Paleozoic sediments.

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