Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 108 for “"Songbirds"”.
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Urbanization affects environmental conditions for developing songbirds
Urbanization introduces a set of novel stressors for animals in these modified habitats. Developing young, in particular, can be at risk due to increased predation, exposure, and high food intake requirements. Song sparrows (Melospiza melodia) are a model wild songbird system that persist in both …
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Long-distance navigation and magnetosensory mechanisms in migratory songbirds
Ungeachtet vieler wissenschaftlicher Erkentnissgewinne im Bereich der Orientierungs und Navigationsmechanismen von Zugvögeln während ihrer Migrationen, verbleiben diesbezüglich viele Fragen unbeantwortet. Im Rahmen meiner sieben Publikationen umfassenden Doktorarbeit, habe ich hauptsächlich …
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Natural and Experimental Noise Affects Acoustic Communication in Songbirds
<p>Background noise is ubiquitous and can impair acoustic communication and influence signaling behavior in animals. Despite evidence demonstrating myriad effects of anthropogenic noise on animal communication, precisely how natural background noise influences communication and behavior remains …
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Migratory Stopover of Songbirds in the Western Lake Erie Basin
Songbirds use multiple stopover locations to rest and refuel for subsequent flights while migrating between breeding and non-breeding areas. Selection of high quality stopover habitat may allow migrants to minimize time and energy spent in migration and maximize fitness. Migrants should therefore …
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Tick Infestations and Their Consequences for Migratory Songbirds During Spring Stopover
<p>Migratory birds face a number of challenges during their seasonal movement from tropical/sub-tropical Central and South America to more temperate North America. Maintaining health during migration is of particular concern. This study seeks to understand how haematophageous ectoparasites, such as …
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The effect of urbanization on the stopover ecology of neotropical migrant songbirds
I conducted spring migration point counts and vegetation surveys at 29 forest patches in the Chicago, IL metropolitan area in 2012 and 2013. The forest patch selection was designed to test the effects of patch size, distance from the Lake Michigan shoreline and degree of urbanization. I conducted …
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The design and assembly of neural circuits for vocal communication in songbirds
… produces few neurons in adulthood, the brains of songbirds continue to produce new neurons throughout life. The function of these new neurons is not know, although it has been suggested that they endow the avian brain with a remarkable regenerative capacity that does not exist in mammals. It has …
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The Effects of Hackberry Psyllids on Refueling Migratory Songbirds and Autumnal Seed Rain
… during autumn, a period of time when migratory songbirds are traveling from their breeding areas in temperate North America south to their winter ranges. These migrations are energetically taxing and many songbirds fuel their journey with resources like insects and fruits. I captured birds with …
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The role of social environment in shaping vocal communication systems in wild songbirds
For many taxa, vocal communication is an essential means of navigating continuously changing social and ecological environments. Among passerine birds, vocal signals are critical to survival and play an important role in mate attraction, territory defense, and predator avoidance. In my …
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Spring Phenology and Trophic Ecology of Trees, Caterpillars, and Migrating Neotropical -Nearctic Songbirds
I investigated the trophic ecology of forest trees, caterpillars, and wood warblers (Parulidae) and vireos (Vireonidae) during spring migration in 2001--2003 at Trelease Woods, a deciduous forest fragment near Urbana, Illinois, USA (40°09'N, 88°10'W). I hypothesized that (1) the …
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Neural mechanisms of early motor control in the vocal behavior of juvenile songbirds
An infant reaches out for her new toy, struggling day after day to simply grasp her fingers around it. A few years later, she hits a tennis serve, perfect in the timing of its intricately choreographed movements. How does a young brain learn to use the muscles it controls, to properly coordinate …
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The role of basal ganglia-forebrain circuitry in the vocal learning of songbirds
… are implicated in numerous human diseases. In songbirds, as in mammals, basal ganglia-forebrain circuits are necessary for the learning and production of complex motor behaviors; however, the precise role of this circuitry remains unknown. This thesis is an investigation into how the anterior …
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Neural mechanisms underlying the emergence of rhythmic and stereotyped vocalizations in juvenile songbirds
… learned motor skills, I use vocal learning in songbirds as a model. While previous studies have shown that a premotor area in the songbird brain, HVC, is important for stereotyped adult song, the role of HVC in juvenile song is less known. This thesis characterizes how activity in HVC develops …
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Impacts of elk management and riparian condition on songbirds in Rocky Mountain National Park
The widespread loss of apex predators from the western U.S. is having cascading effects on ecosystems. As in other western parks, riparian willow (Salix spp.) communities in Rocky Mountain National Park (RMNP) are declining as a result of a trophic cascade involving the local extinction of wolves …
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Abundance Of Songbirds In Eastern Hemlock Stands Following Chemical Treatment For Hemlock Woolly Adelgid
<p>In the 1960’s the invasive Hemlock Woolly Adelgid (Adelges tsugae [hereafter, HWA]) began to spread west across the hemlock stands of the Eastern U.S. killing a significant number of Eastern Hemlock (Tsuga canadensis). While chemical treatments, primarily with the active ingredient imidacloprid, …
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Analysis of Novel Genes Whose mRNAs are Enriched in the HVC-Associated Telencephalon of Songbirds
<p>7 cloned cDNAs were selected for analysis due to the enrichment of their corresponding RNAs in the canary HAT, a telencephalic region immediately surrounding and including song nucleus HVC. The goal of the analysis was to determine what kind of protein is encoded by each RNA, whether the RNA …
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Testing proximate causes and ultimate explanations of social cue use for habitat selection by songbirds
… on fitness. There is growing evidence that songbirds select habitat using social cues emitted from individuals present in the habitat. Using the Yellow Warbler (Setophaga petechia), I designed multiple playback experiments to test what types of social cues animals use for habitat selection, …
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The distinct neural mechanisms underlying the production of stereotyped and exploratory vocal behavior in songbirds
Whether it is speaking to one another, or nailing a tennis serve, humans can perform an incredible range of behaviors, most of which are learned. How do we and other animals learn complicated sequential behaviors, and once they are learned how are they executed? This thesis is an investigation into …
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