Date of Award

8-2012

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Legacy Department

Wildlife and Fisheries Biology

Advisor

Johnson, Ron J.

Committee Member

Bowerman , William W.

Committee Member

Baldwin , Robert F.

Committee Member

Bridges , William C.

Abstract

Current natural resource challenges include global alteration of land cover, loss of biodiversity, impacts from increasing demands for agricultural products, and climate change. Birds are often used to assess the effects of ecological stressors because they are sensitive to environmental changes, ubiquitous and charismatic, and long-term monitoring programs have been in place for more than a century. I demonstrate the effects of climate change on avian migration and nesting dates and the potential value of using interdisciplinary approaches and citizen science to address contemporary ecological challenges. I examine Ruby-throated Hummingbird (Archilochus colubris) migration in the eastern United States from 1880-2010 and demonstrate a migratory advancement of approximately two weeks that varies by latitude. Extended migratory stopovers in mid-latitudes during warmer winters may affect synchrony between birds and their breeding habitats and impede some pollination and pest suppression services birds provide. Possible sources of bias in data collected by amateur naturalists, particularly the tendency for avian 'first' arrivals to be reported on weekends, is decreasing over time in North America, is less than reported in Europe, and can be overcome by accounting for `day of week' in models that assess phenology. Incorporating these findings will make conclusions more robust in studies that use first arrival dates to assess the effects of climate change. Growing degree-days provide a tool to predict nesting dates of common bird species in the eastern United States and to assess the effects of temperature across trophic levels in agroecosystems. This information could facilitate communication between farmers and ecologists and promote biological pest control and bird conservation on farms. Cooperation among governmental agencies, university scientists, and the general public has helped revive a legacy dataset that chronicles bird migration for more than 800 species in North America during the past century. I demonstrate how these data could be used to understand the effects of climate change on bird migration and propose possible research questions that could be addressed from these data. I describe how graduate students are well-positioned to bridge the information gap that exists between research scientists and field practitioners. I provide suggestions to advisors and university administrators on how to best support this process and argue that being exposed early to the broader issues of research and implementation may enhance the graduate research experience and improve conservation outcomes. Land-use models demonstrate effects of urbanization on important bird and amphibian species in South Carolina and identify biologically important areas most at-risk from human development. These findings could inform management and land-use decisions at various spatial scales. Taken together, my work demonstrates impacts of climate change and urbanization on avian species, provides creative solutions to conservation challenges within interdisciplinary frameworks, bridges gaps between researchers and field practitioners, and overcomes barriers to using citizen science data in research. Although the ecological challenges facing humanity are well-documented, science and technology are also advancing. Implementation of innovative and interdisciplinary conservation strategies, such as those presented here, will provide guidance for positive conservation outcomes.

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