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Full-Text Articles in Ornithology

Evaluating Avian Use Of Cover Crops In The Corn Belt, Megan Figura Jan 2022

Evaluating Avian Use Of Cover Crops In The Corn Belt, Megan Figura

Electronic Theses and Dissertations

The tallgrass prairie of North America has changed drastically since colonial settlement, with up to 99% of this region converted for agriculture and other land-uses. Concurrent with grassland conversion, grassland birds have experienced the most extreme, consistent, and widespread population declines of any avian guild. Agricultural lands in the U.S. Midwest were able to provide adequate habitat for several bird species until the 1950’s; however, altered and intensified management practices have degraded much of remaining suitable habitat and undermined ecosystem functions. Consequently, many grassland birds have been identified as Species of Greatest Conservation Need (SGCN) in many State Wildlife Action …


Predation Threat In A Variable Landscape: Connecting Predation Risk To Nesting Success For The Seaside Sparrow (Ammospiza Maritima Macgilivraii), Corina D. Newsome Jan 2021

Predation Threat In A Variable Landscape: Connecting Predation Risk To Nesting Success For The Seaside Sparrow (Ammospiza Maritima Macgilivraii), Corina D. Newsome

Electronic Theses and Dissertations

Predation, the leading cause of nest-failure in birds, not only exists as a direct threat to nesting success, but may exacerbate other sources of nest mortality. Birds inhabiting Atlantic coastal marshes, such as Seaside Sparrows (Ammospiza maritima; hereafter SESP), are experiencing significant and rapid changes to their habitat, particularly sea level rise (SLR) and encroaching urbanization, that may affect the relative influence of nest predation on overall productivity. For SESPs, SLR presents an inherent threat to nest success in its potential to increase the frequency of nest flooding. In addition to this direct threat, the ability of SESPs …


Analyzing The Longevity Of Sperm Within The Female Japanese Quail By Assessing Sperm Penetration Of The Perivitelline Layer Under Optimal And Suboptimal Conditions., Garret G. Ashabranner, Joey L. Bray Aug 2020

Analyzing The Longevity Of Sperm Within The Female Japanese Quail By Assessing Sperm Penetration Of The Perivitelline Layer Under Optimal And Suboptimal Conditions., Garret G. Ashabranner, Joey L. Bray

Electronic Theses and Dissertations

After mating, birds have the ability to store semen within the female reproductive tract. The sperm storage tubules will store and subsequently release semen to travel up the oviduct. Sperm cells that make the trek up the oviduct have a chance to fertilize the ovum. These sperm cells will bind to the perivitelline layer of the ovum and hydrolyze a hole in the perivitelline layer, where it has the possibility to fertilize the female sex cell. Analyzing the number of penetration points on the perivitelline layer is an effective way to analyze reproductive efficiency. Many environmental factor has its effect …


Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow May 2020

Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow

Electronic Theses and Dissertations

Avian facial plumage, bill coloration, and feather microstructure may serve one or more adaptive functions. Several researchers have proposed that dark eyestripes, bills, and facial masks aid in reducing glare, however, there have been relatively few tests of this hypothesis. Dark facial markings have been shown to have an adaptive glare-reduction function in recent field studies of a few species, but this hypothesis has never been tested in a broad multispecies analysis. It is likely that feather microstructure influences feather brightness and has an effect on the efficacy of glare reduction properties of feathers. I examined the link between dark …


Behavioral Ecology Of Landbird Migrants In A Complex And Changing Flyway System: The Gulf Of Maine, Adrienne J. Leppold Aug 2016

Behavioral Ecology Of Landbird Migrants In A Complex And Changing Flyway System: The Gulf Of Maine, Adrienne J. Leppold

Electronic Theses and Dissertations

In and around the Gulf of Maine, over 300 species of birds have been documented during migration, and tens of millions of songbirds may pass through the region on a single autumn night. Shorelines are widely documented as major migration corridors. There is ample evidence that coastal areas concentrate migrants and many species make overwater movements to and from breeding and wintering grounds. Data collected from radar, banding, and ceilometry studies in the northeast have provided us with evidence that birds migrate along the coast and make overwater movements across the Gulf of Maine and Bay of Fundy during both …