Life Sciences Commons^™

Seasonality Of The Stress Response In House Sparrows (Passer Domesticus)., Michael R. Hasstedt

Electronic Thesis and Dissertation Repository

Seasonal changes in plasma corticosterone (CORT) levels indicate that birds modify their stress response through the year. Although this has been well documented, the method by which birds achieve this seasonality is not well understood. In this study I used house sparrows to determine if changes in glucocorticoid receptor (GR) immunoreactivity in several stress-related brain nuclei showed seasonal variation. The house sparrowsshowed seasonal variation in their stress response with baseline CORT levels being highest during the breeding season and lowest during winter. There was also significant change in plasma CORT post-dexamethasone during breeding, but not during other times of the …

Occupancy Modeling Of Herpetofauna And Grassland Nesting Birds At Quivira National Wildlife Refuge, Kasandra A. Brown

Master's Theses

Only about 11% of native grasslands remain in the United States (North America Bird Conservation Initiative, 2011). Grasslands are a considerable source of biodiversity and play a crucial role in nutrient cycling (Suttie et al. 2005; Holechek et al. 2011). Stewards, such as the US Fish and Wildlife Service, are essential to grassland conservation, especially in Kansas, where less than one percent of land is under federal stewardship or public trust (Holechek et al. 2011). Quivira National Wildlife Refuge, an 8,900 hectare refuge located in Stafford County, has traditionally been managed as a stopover for migratory birds, but is now …

The Effects Of Urbanization On Tick Parasitism Rates In Birds Of Southeastern Virginia, Erin Leigh Heller

Biological Sciences Theses & Dissertations

The coastal region of southeastern Virginia is one of the largest urban areas along one of North America’s migratory flyways. Because hundreds of avian species use this flyway, understanding factors affecting birds and their health is of paramount concern. Within this region, 14 species of ticks have been documented, all of which may serve as vectors of mammal (including human) pathogens. By sampling birds at sites of varying levels of urbanization within the coastal southeastern urban matrix, I studied the relationship between ticks and their avian hosts, and how this relationship varies seasonally. Mistnets were set-up at five permanent sites …

Intra- And Interspecific Variation In Demographic Rates And Niche Across The Range Of A Species, The Saltmarsh Sparrow (Ammodramus Caudacutus), Katharine J. Ruskin

Electronic Theses and Dissertations

In this project, we examined various hypotheses that address one of the fundamental questions in ecology and evolution: what determines the range of a species? We used demographic data for saltmarsh sparrows (Ammodramus caudacutus) collected over the majority of the global breeding range. Saltmarsh sparrows are considered threatened by climate change, specifically sea level rise, which is predicted to result in loss of the tidal marsh habitat where saltmarsh sparrows live across their entire life cycle. For my dissertation, I investigated the reproductive biology of saltmarsh sparrows both to provide vital information for wildlife managers and to explore …

Constraints On Distributions And Diversity Of Birds And Mammals Over Variable Environments, Trevor S. Fristoe

Biology ETDs

The distributions of species are determined by intrinsic factors such as physiological tolerances as well as extrinsic factors of the environment such as the availability of resources. While physiological tolerances generally change over evolutionary time scales, changes in environmental productivity due to processes such as succession or seasonal progression often occur over ecological times. I address both physiology and resource availability as drivers of the distributions and diversity of endothermic birds and mammals using a macroecological approach and a metabolic perspective. Migratory birds, altering communities over seasonal cycles, provide a unique opportunity to investigate the drivers of distributions and diversity …

Evolution And Ecology Of Two Iconic Australian Clades: The Meliphagidae (Birds) And The Hakeinae (Plants), Eliot Trimarchi Miller

Dissertations

The first part of this dissertation explores the evolution of two iconic groups of species through Australian climate space: the Meliphagidae, or honeyeaters, which are primarily nectar-feeding birds, and the Hakeinae, a section of the plant family Proteaceae. Both groups are inferred to have had their origins in Gondwanan rainforests that were widespread across Australia 45 million years ago and then diversified into more arid environments as the continent’s climate became more arid. Accordingly, dry environments are inhabited by closely related (phylogenetically clustered) sets of species, although, in contrast to the honeyeaters, Hakeinae communities are characterized by more localized diversification. …

Master's Project: An Ecological Assessment Of Backcountry Ski Trails At Bolton Backcountry In Bolton, Vt, Kathryn T. Wrigley

Rubenstein School Masters Project Publications

The Vermont Department of Forests, Parks, and Recreation (FPR) acquired the 1,144-acre Bolton Valley Nordic and Backcountry Ski Trails Parcel in 2013. Backcountry skiing is a fast growing sport in Vermont and FPR is currently working on a management strategy for this new use. My project seeks to inform FPR's long-term management plan of the Bolton Valley Nordic and Backcountry Ski Trail Parcel as well as provide information for state-level planning.

My primary goal was an ecological assessment of gladed ski trails on wildlife habitat suitability. I used United States Fish and Wildlife Habitat Suitability Indexes as well as primary …