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Full-Text Articles in Ecology and Evolutionary Biology

The Evolution Of Dragons, Laura J. Mayfield Jan 2020

The Evolution Of Dragons, Laura J. Mayfield

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Dragons have been depicted in human art as early as 4500 BCE. For centuries, these fantasy creatures have inspired countless folk and fantasy tales, as well as appearing in the art of different cultures around the world. Now there are thousands of different depictions of these huge, flying, fire-breathing lizards, but are any of them possible? In this study, I reference peer-reviewed scientific articles, phylogenetic analysis, and paleoart studies to create biologically-sound dragons. Basing the dragon lineage on a real branch of webbed-winged scansoriopterygids—an extinct family of climbing and gliding maniraptoran dinosaurs—I explored the possible wing-structure, fire-breathing abilities, and effects …


Golden Eagle Resource Selection And Environmental Drivers Of Reproduction In The Northern Range Of Yellowstone National Park, David Brown Haines Jan 2020

Golden Eagle Resource Selection And Environmental Drivers Of Reproduction In The Northern Range Of Yellowstone National Park, David Brown Haines

Graduate Student Theses, Dissertations, & Professional Papers

In the United States (US), National Parks are considered the “crown jewels” of protected lands. However, the importance of National Parks to wildlife populations and the species that inhabit them is not often quantified, thus, requiring a better understanding of National Parks as a conservation tool. Golden eagles (Aquila chrysaetos) are a North American species of conservation concern and territories in the northern range of Yellowstone National Park (YNP) are relatively dense. However, average reproductive rates over the past ten years (2011-2020) have been low (productivity = 0.34, nest success = 28%). The contrast of high density and …


Quantifying False Positives In Avian Survey Data, Kaitlyn M. Strickfaden Jan 2018

Quantifying False Positives In Avian Survey Data, Kaitlyn M. Strickfaden

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Imperfect detection is a known issue when conducting count-based surveys in wildlife studies. False positive detections, observed occurrences of individuals that truly are not present, are often assumed to not occur. This assumption can bias detection rates and create misleading results when calculating population estimates. Survey methods such as the dependent double-observer method are suggested to reduce the occurrence of false positives (Nichols et al. 2000). My study quantified and compared rates of false positives in a single-observer method and a dependent double-observer method using computer-generated auditory surveys. I categorized volunteer observers as either inexperienced or experienced and asked them …


Lewis’S Woodpecker Nest Success And Habitat Selection In Cottonwood Floodplain Versus Burned Conifer Forests, William M. Blake Jan 2018

Lewis’S Woodpecker Nest Success And Habitat Selection In Cottonwood Floodplain Versus Burned Conifer Forests, William M. Blake

Graduate Student Theses, Dissertations, & Professional Papers

Breeding habitat selection influences reproductive outcomes. Habitat selection may be adaptive and benefit populations, but it can also be maladaptive with negative consequences for populations. Understanding habitat selection and its influence on reproductive success, especially in species of concern, is critical for effective management. Lewis’s Woodpecker (Melanerpes lewis) is a Species of Concern that has experienced national population declines. We studied its abundance and reproductive success in two commonly selected breeding forest types (i.e., cottonwood floodplain and mixed-conifer burned), and nest-site characteristics (nest availability, food availability, and vegetation attributes) that have the potential to yield strong differences in …


High-Resolution Mapping Of Hierarchical Greater Sage-Grouse Nesting Habitat: A Grain-Spectrum Approach In Northwestern Wyoming, Robert T. Haynam Iii Jan 2017

High-Resolution Mapping Of Hierarchical Greater Sage-Grouse Nesting Habitat: A Grain-Spectrum Approach In Northwestern Wyoming, Robert T. Haynam Iii

Graduate Student Theses, Dissertations, & Professional Papers

Our overall objective was to create a probabilistic nesting-habitat map for the Jackson Hole sage-grouse population that would have utility as a tool for future research, conservation, and management. The models that we developed for this purpose were specified to evaluate whether sage-grouse may be selecting nesting-habitat characteristics simultaneously at various spatial scales. Our spatially-explicit landscape-scale research was implemented primarily with readily available National Agriculture Imagery Program (NAIP) data. All nesting data was collected from 2007-2010. We tested how a broad range of grain sizes (spatial resolution) of covariate values affected the fit to logistic regression models used to estimate …


Cows And Plows: Science-Based Conservation For Grassland Songbirds In Agricultural Landscapes, Marisa K. Lipsey Jan 2015

Cows And Plows: Science-Based Conservation For Grassland Songbirds In Agricultural Landscapes, Marisa K. Lipsey

Graduate Student Theses, Dissertations, & Professional Papers

Temperate grasslands are among earth’s most imperiled ecosystems. In North America, steep declines of endemic songbird populations indicate that grassland loss and degradation may be approaching critical levels. Grasslands are agricultural landscapes largely (~85%) under private ownership with little formal protection status. Remaining bird populations depend on grazing lands that have not been converted to cropland. We combine regional data from a hotspot for grassland bird diversity (northeast Montana, USA; 26,500-km2) with continental data spanning the northern Great Plains (1,000,000-km2) to evaluate how land use and management influence bird distribution and abundance. Regionally, habitat used by seven grassland specialists spanned …