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Full-Text Articles in Life Sciences

The Birds And The Trees: Quantifying The Drivers Of Whitebark Pine Decline And Clark's Nutcracker Habitat Use In Glacier National Park, Vladimir Kovalenko Jan 2023

The Birds And The Trees: Quantifying The Drivers Of Whitebark Pine Decline And Clark's Nutcracker Habitat Use In Glacier National Park, Vladimir Kovalenko

Graduate Student Theses, Dissertations, & Professional Papers

Whitebark pine (Pinus albicaulis), recently listed as threatened under the Endangered Species Act, is in steep decline in Glacier National Park, Montana, USA due to the non-native pathogen Cronartium ribicola, causal agent of the fatal disease white pine blister rust. A sample of the park’s population suggests that approximately 70 percent of whitebark pines have died, while 65 percent of the remaining trees are infected. Using landscape and climate variables, we show how geographic location, elevation, aspect, solar radiation, relative humidity, and snowpack interact with tree diameter to affect mortality, disease incidence, cone production, and regeneration. We also examine how …


Federal Funding Statutes And State-Federal Wildlife Authority: Did Congress Demonstrate A Preference For State Wildlife Management Authority With Pittman-Robertson And Dingell-Johnson?, James Vaughan Branch Jan 2023

Federal Funding Statutes And State-Federal Wildlife Authority: Did Congress Demonstrate A Preference For State Wildlife Management Authority With Pittman-Robertson And Dingell-Johnson?, James Vaughan Branch

Graduate Student Theses, Dissertations, & Professional Papers

The Federal Aid in Wildlife Restoration Act of 1937 now known as Pittman-Robertson and Federal Aid in Sport Fish Restoration Act of 1950 now known as Dingell-Johnson are federal statutes which stand as the original and perhaps most significant federal funding statutes supporting state wildlife conservation and management. Congress’s decision to pass these statutes may be argued to be a prima facie endorsement of state wildlife agencies (SWA) as the primary managers of wildlife since each statute dedicated substantial federal excise revenue to SWAs. We hypothesized we would find consistent evidence in favor of primary state management authority over wildlife. …


Evaluating The Management And Consequences Of Hybridization Between Nonnative Rainbow Trout And Native Westslope Cutthroat Trout, Anthony James Dangora Jan 2022

Evaluating The Management And Consequences Of Hybridization Between Nonnative Rainbow Trout And Native Westslope Cutthroat Trout, Anthony James Dangora

Graduate Student Theses, Dissertations, & Professional Papers

The introduction of nonnative fish is a major driver in the decline of native fish species. Nonnative rainbow trout (Oncorhynchus mykiss; RBT) introduced into the native range of westslope cutthroat trout (O. clarkii lewisi; WCT) have led to the introgressive hybridization between these two species. This widespread hybridization is a primary threat to the long-term persistence of WCT as it can cause population-level genomic extinction. Since there are no set management solutions for hybridization, there is a need to evaluate the different conservation approaches to ensure the persistence of WCT populations. Additionally, beyond propagule pressure, the array of drivers that …


Body Temperature And Reproductive Effort In A Long-Lived Tropical Songbird, Holly R. Jackson Jan 2022

Body Temperature And Reproductive Effort In A Long-Lived Tropical Songbird, Holly R. Jackson

Graduate Student Theses, Dissertations, & Professional Papers

Heat production relative to dissipation rates have constrained reproductive effort and reduced fitness in short-lived, temperate birds. To determine whether heat constrains reproductive effort in long-lived taxa with low reproductive effort, we experimentally clipped plumage from tropical Gray-throated babblers (Stachyris nigriceps) to increase heat dissipation rates. Contrary to findings in short-lived species, we found no strong evidence of heat dissipation constraints on reproductive effort in our mid-elevation study. Clipped adults did not increase feeding rates compared to controls, but clipped females did spend more time incubating and brooding eggs and young. Increased time in the nest may reduce increased heat …


A Reintroduction Retrospective: Comparative Fisher (Pekania Pennanti) Survival And Prey Habitat Use In The Cascade Mountains Of Washington State, Tanner S.T. Humphries Jan 2021

A Reintroduction Retrospective: Comparative Fisher (Pekania Pennanti) Survival And Prey Habitat Use In The Cascade Mountains Of Washington State, Tanner S.T. Humphries

Graduate Student Theses, Dissertations, & Professional Papers

Increasing human impacts on biodiversity highlight the global need for ecological restoration. For many wildlife species, reintroduction is necessary to re-establish populations in parts of their historic range where they have been extirpated. Reintroduction efforts are commonly used to help restore ecosystem integrity, but are often expensive, time consuming, and unsuccessful at generating self-sustaining populations. Thus, a more complete understanding of the factors affecting restoration success is important for ensuring successful outcomes and responsible stewardship. Fishers (Pekania pennanti) are one of the most commonly reintroduced carnivores in North America, but the success of such efforts is highly variable, …


Influence Of Livestock And Electrified Fences On Livestock Depredation And Habitat Selection By Grizzly Bears In The Mission Valley, Montana, Kari Lynn Eneas Jan 2020

Influence Of Livestock And Electrified Fences On Livestock Depredation And Habitat Selection By Grizzly Bears In The Mission Valley, Montana, Kari Lynn Eneas

Graduate Student Theses, Dissertations, & Professional Papers

Balancing protection between livestock and carnivores has been a long-standing challenge in conservation. When encounters between carnivores and livestock or humans result in conflict or livestock depredation, the safety of both wildlife and humans are at risk. Reducing livestock depredation by grizzly bears (Ursus arctos horribilis) will be important as populations continue to recover and expand beyond public lands in the Northern Continental Divide Ecosystem. We used GPS locations from 8 female grizzly bears spanning 5 years in the Mission Valley, Montana, to evaluate the effect of livestock on habitat selection of grizzly bears. The Mission Valley is located on …


Finding Fishers: Determining The Distribution Of A Rare Forest Mesocarnivore In The Northern Rocky Mountains, Jessica M. Krohner Jan 2020

Finding Fishers: Determining The Distribution Of A Rare Forest Mesocarnivore In The Northern Rocky Mountains, Jessica M. Krohner

Graduate Student Theses, Dissertations, & Professional Papers

The Northern Rocky Mountain fisher population (Pekania pennanti), is classified as a Species of Greatest Conservation Need and is of special concern to state, federal, and tribal entities. In this thesis, we present methods to effectively survey fishers across the northern Rockies of Idaho and Montana, and provide estimates of fisher distribution at a population range-wide scale through occupancy analyses. We also assess factors that influence fisher occurrence through covariate analyses and identify core fisher habitat in the northern Rockies through spatial occupancy modeling. By sampling broadly across the landscape, we provide baseline distributional data for comparison against …


Selection Of Forage And Avoidance Of Predation Risk By Partially Migratory Mule Deer, Collin Jeffrey Peterson Jan 2020

Selection Of Forage And Avoidance Of Predation Risk By Partially Migratory Mule Deer, Collin Jeffrey Peterson

Graduate Student Theses, Dissertations, & Professional Papers

Migration by ungulates has traditionally been thought of as a strategy that increases access to forage quality or reduces exposure to risk of predation, but the benefits of migration may be waning globally. In partially migratory populations, the persistence of both migrant and resident strategies is an intriguing ecological phenomenon, because migrants and residents often face contrasting fitness consequences. Partial migration is common in mule deer (Odocoileus hemionus), a species that has experienced widespread declines across the western United States during recent decades. Mule deer seldom switch between migratory strategies throughout their lifetime, which may make them less resilient to …


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 Coat Color Phenology Of Sympatric Snowshoe Hares And Weasels, Brandon Murray Davis Jan 2019

Quantifying Coat Color Phenology Of Sympatric Snowshoe Hares And Weasels, Brandon Murray Davis

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.


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 …


Impacts Of Elephant Crop-Raiding On Subsistence Farmers And Approaches To Reduce Human-Elephant Farming Conflict In Sagalla, Kenya, Sophia Weinmann Jan 2018

Impacts Of Elephant Crop-Raiding On Subsistence Farmers And Approaches To Reduce Human-Elephant Farming Conflict In Sagalla, Kenya, Sophia Weinmann

Graduate Student Theses, Dissertations, & Professional Papers

As human and elephant populations grow in Kenya, elephants increasingly leave parks to eat farmers’ crops while foraging, which creates epicenters of human-elephant conflict (HEC). This conflict compromises farmers’ food and economic security, impedes elephant conservation initiatives, and threatens the safety of humans and elephants. In recent years, the situation has been exacerbated by drought and national-level infrastructure development that bisects key elephant habitat. Although researchers have widely studied elephant populations, few have examined the cultural, economic, and emotional effects of HEC on subsistence farmers. This project utilized a mixed methods approach to address this knowledge gap and understand the …


Integrated Stress And Community Perceptions: Toward An Understanding Of Human-Cougar Tolerance, Lara Brenner Jan 2017

Integrated Stress And Community Perceptions: Toward An Understanding Of Human-Cougar Tolerance, Lara Brenner

Graduate Student Theses, Dissertations, & Professional Papers

Evidence suggests that cougars (Puma concolor) are beginning to recolonize their traditional range in the Midwestern and Eastern US, returning to a landscape and a social environment that have changed drastically in a century of absence. Any hope of the cougar’s persistence depends on both human tolerance of their presence and on cougar tolerance of disrupted habitat. In this thesis, we took advantage of diverse cougar policy in place in the Western US to explore variation in human attitudes and acceptability of cougars and in the cougar stress response. We validated a process to identify and extract cortisol …


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 …


Habitat Quality Influences Migratory Strategy Of Female White-Tailed Deer, Charles R. Henderson Jr. Jan 2014

Habitat Quality Influences Migratory Strategy Of Female White-Tailed Deer, Charles R. Henderson Jr.

Graduate Student Theses, Dissertations, & Professional Papers

Partial migration is a life history strategy that is common for ungulate species living in seasonal environments. One factor that influences the decision to migrate by ungulates is access to high quality habitat. We evaluated the influence of access to winter habitat of high quality on the probability of an individual migrating, the differences in seasonal habitat use between and within migratory and resident classes of deer, and the effects of this decision on the survival of female white-tailed deer. We hypothesized that deer with home ranges of relatively low quality in winter would have a relatively high probability of …


Effects Of Road-Stream Crossings On Populations Of The Idaho Giant Salamander (Dicamptodon Aterrimus), Richard K. Honeycutt Jan 2014

Effects Of Road-Stream Crossings On Populations Of The Idaho Giant Salamander (Dicamptodon Aterrimus), Richard K. Honeycutt

Graduate Student Theses, Dissertations, & Professional Papers

Habitat disturbances affect wildlife populations through numerous mechanisms, and determining specific components of habitat disturbances affecting those populations is challenging. For example, a single disturbance can both change local habitat conditions and impose limitations on dispersal of animals. Both of these components can negatively affect biological responses, such as body condition, local movement patterns, or survival. Culverts are a habitat disturbance having both of these components. Culverts affect local habitat conditions by increasing sediment levels in downstream reaches, negatively affecting animals downstream of culverts. Culverts also impose limits on dispersal by blocking passage of stream organisms to upstream reaches, negatively …