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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

Golden-winged warbler (Vermivora chrysoptera) demographics and habitat use and the potential effects of land use change on gold-winged and cerulean warblers (Dendroica cerulea) in the Cumberland mountains of Tennessee

Bulluck, Lesley Penfield, January 2007 (has links) (PDF)
Thesis (Ph. D.)--University of Tennessee, 2007. / Title from title page screen (viewed on November 1, 2007). Thesis advisor: David A. Buehler. Vita. Includes bibliographical references.
2

Playback surveys and breeding habitat characteristics of golden-winged warblers (Vermivora chrysoptera) on high-elevation pasturelands on the Monongahela National Forest, West Virginia

Aldinger, Kyle Ray. January 2010 (has links)
Thesis (M.S.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains ix, 99 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references.
3

Conspecific Attraction in a Low-Density Population of a Threatened Songbird

Albrecht-Mallinger, Daniel James 01 May 2014 (has links)
Many organisms use both vegetation structure and social cues in selecting habitats. Many species of songbirds use the presence of breeding conspecifics as a social cue and sign of habitat quality, and can be induced to settle in unoccupied habitats by artificially broadcasting breeding song, a process referred to as “conspecific attraction”. In our study, we tested response to conspecific attraction a low-density population of the threatened Golden-winged Warbler (Vermivora chrysoptera) in Highland County, VA. Response to broadcast song was observed, with a modest increase in mean male abundance at survey points within 250 meters of treatments, and mean abundance decreasing outside of this range throughout the study area. Recruitment to conspecific playback was lower in our study than observed in previous research on high-density systems. Our results suggest more research is needed of the effectiveness of conspecific attraction in low density species and that its use should be tailored to the spatial and demographic conditions of the managed population.
4

Generating Best Management Practices for Avian Conservation in a Land-Sparing Agriculture System, and the Habitat-Specific Survival of a Priority Migrant

Ritterson, Jeffrey D 23 November 2015 (has links)
A large amount of the world’s biodiversity is located in a disproportionately small amount of area, namely the tropics. Many of these areas are experiencing rapid landscape changes, mainly in the form of deforestation for agricultural practices. Current conservation efforts are focused on agricultural areas and their ability to provide habitat. The conservation value of a novel land-sparing agroforestry system, known as Integrated Open Canopy (IOC), was recently demonstrated on the study site when applied to coffee. IOC coffee supports forest species that are uncommon or absent in shade grown coffee. I generated best management practices for IOC farms relative to the conservation of forest-dependent birds by examining what features support the highest richness of species. The goal was to help develop guidelines for the implementation of IOC grown coffee. The Golden-winged warbler (Vermivora chrysoptera) is a Neartic-Neotropical migrant of high conservation priority which has been documented using a range of nonbreeding habitat types, including IOC coffee farms. However, as is the case with many migrant species, little is known about whether survival differs among habitats. Though generally forest dependent, previous work found Golden-winged warblers select for habitat features other than categorical forest types, such as canopy height and microhabitat features. In an attempt to identify quality nonbreeding habitat, I estimated Golden-winged survival rates specific to an array of habitat features.
5

Avian Ecology and Conservation in Tropical Agricultural Landscapes with Emphasis on Vermivora Chrysoptera

Chandler, Richard Brooks 01 February 2011 (has links)
The world's biodiversity is concentrated in tropical ecosystems, yet tropical forests are being converted for agriculture at a rapid rate. I evaluated the potential of an alternative coffee production system known as Integrated Open Canopy (IOC) to contribute to avian conservation. This study was conducted from 2005-2010 in the Cordillera de Tilarán, Costa Rica. My results indicate that species richness of forest-dependent birds was higher in IOC farms than in shade coffee farms, and was comparable to secondary forest sites. There was no difference in species richness of Neotropical-Nearctic migrants between IOC and shade coffee farms. Overall similarity was higher between IOC farms and primary forest than between shade coffee farms and primary forest. he golden-winged warbler Vermivora chrysoptera is a declining Neotropical-Nearctic migrant bird, yet little is known about its non-breeding season ecology and demographics. I found that golden-winged warbler abundance was highest at intermediate precipitation levels found at middle elevations (1000-1200 m) of the Pacific slope, but they were absent from the dry forests at lower elevations on the Pacific slope. Abundance peaked in forests with canopy heights of 22 m, and was positively related to the quantity of hanging dead leaves. Radio-telemetry data indicated that golden-winged warblers used microhabitat features characteristic of disturbance more frequently than expected by chance. Selection of these microhabitat features was related to their highly specialized dead-leaf foraging behavior, which may also have contributed to their high degrees of site fidelity, mixed-species flock attendance, and territoriality. These behaviors have important conservation implications because they constrain density, and thus could affect carrying capacity. Population dynamics were characterized by estimating plot-level and individual-level apparent survival and recruitment rates within and among non-breeding seasons. Both levels of analysis suggested that recruitment was too low to offset mortalities within this study area. This study indicates that increasing forest cover in tropical agricultural landscapes may be the most effective way of providing habitat for bird species of high conservation concern, including the golden-winged warbler. Integrated open canopy coffee production is one option for achieving this goal because it provides a financial incentive to protect or restore forest.

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