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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

Effects of fire on the distribution and abundance of Sprague's pipit (Anthus spragueii) and their invertebrate prey.

Champagne, Janessa 13 September 2011 (has links)
The Sprague’s pipit is a small, threatened grassland songbird endemic to the Canadian prairies and to the northern Great Plains of the United States. Between 1968 and 2006, the population of Sprague’s pipit in Canada experienced a significant annual decline of 4.5%. The prairie provinces also experienced declines within this reporting period. Pipits are more abundant in native prairie grasslands, however much of their preferred habitat has been lost due to the influence of human activities. Furthermore, management of remaining grasslands has impacted the quality of habitat through suppression of natural disturbances such as fire. Few studies have addressed how fire affects the occurrence and abundance of Sprague’s pipit, thus pipit response to fire is poorly understood. This study investigated the effect of fire on the density and distribution of Sprague’s pipit in south-western Manitoba by examining the associations between pipit density, invertebrate food resources and vegetation structure with fire history. Surveys to determine pipit abundance, invertebrate resources and vegetation structure were conducted in 2007; in 2008 only pipit abundance and vegetation surveys were conducted. Although there was no significant effect of invertebrate resource abundance on Sprague’s pipit density, the abundance of grasshoppers and ground beetles declined with increasing time since last burn, which suggests that longer fire-return intervals may reduce the availability of these prey species for pipits. Fire did not significantly influence the distribution and density of Sprague’s pipit in this region. However the response of the vegetation to fire may indicate that the existing fire-return interval is not contributing to the population decline of Sprague’s pipit, but that in the absence of fire, the habitat could regress to a state that does not meet the critical habitat needs of this species.
2

Effects of fire on the distribution and abundance of Sprague's pipit (Anthus spragueii) and their invertebrate prey.

Champagne, Janessa 13 September 2011 (has links)
The Sprague’s pipit is a small, threatened grassland songbird endemic to the Canadian prairies and to the northern Great Plains of the United States. Between 1968 and 2006, the population of Sprague’s pipit in Canada experienced a significant annual decline of 4.5%. The prairie provinces also experienced declines within this reporting period. Pipits are more abundant in native prairie grasslands, however much of their preferred habitat has been lost due to the influence of human activities. Furthermore, management of remaining grasslands has impacted the quality of habitat through suppression of natural disturbances such as fire. Few studies have addressed how fire affects the occurrence and abundance of Sprague’s pipit, thus pipit response to fire is poorly understood. This study investigated the effect of fire on the density and distribution of Sprague’s pipit in south-western Manitoba by examining the associations between pipit density, invertebrate food resources and vegetation structure with fire history. Surveys to determine pipit abundance, invertebrate resources and vegetation structure were conducted in 2007; in 2008 only pipit abundance and vegetation surveys were conducted. Although there was no significant effect of invertebrate resource abundance on Sprague’s pipit density, the abundance of grasshoppers and ground beetles declined with increasing time since last burn, which suggests that longer fire-return intervals may reduce the availability of these prey species for pipits. Fire did not significantly influence the distribution and density of Sprague’s pipit in this region. However the response of the vegetation to fire may indicate that the existing fire-return interval is not contributing to the population decline of Sprague’s pipit, but that in the absence of fire, the habitat could regress to a state that does not meet the critical habitat needs of this species.
3

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura Elizabeth. January 2010 (has links)
Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on Jan. 22, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Ecology, Department of Biological Sciences, University of Alberta. Includes bibliographical references.
4

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura 06 1900 (has links)
I investigated the effect of energy sector development and introduced crested wheatgrass (Agropyron cristatum) on grassland birds on Canadian Forces Base Suffield. I conducted point counts and mapped breeding territories in 2007 and 2008 for Savannah sparrows (Passerculus sandwichensis), chestnut-collared longspurs (Calcarius ornatus), and Spragues pipits (Anthus spragueii). I found that Savannah sparrows favored areas with taller vegetation, human disturbances and crested wheatgrass in both years. Longspurs used shorter vegetation and in were tolerant of disturbance. Crested wheatgrass was avoided by longspurs in both years. Pipit territories contained similar vegetation to longspurs, were sensitive to disturbance, and avoided placing territories in areas containing crested wheatgrass or trails in both years. Well sites, pipelines and junctions were not avoided by the three species. My research suggests that reducing the number of trails and the spread of crested wheatgrass will increase habitat availability for sensitive species of grassland birds. / Ecology
5

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura Unknown Date
No description available.

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