Ecology and Evolutionary Biology Commons^™

Quantifying Wastewater Contributions To The Upper Clark Fork River, Claire Utzman

Graduate Student Theses, Dissertations, & Professional Papers

Though algae are at the base of food webs in many rivers, large algal blooms are increasing in frequency and can cause problems with nutrient cycling, depletion of oxygen supplies at night, and release of toxic chemicals. One leading cause of algal blooms is nutrient loading into rivers, and controlling nutrient release in wastewater is one approach that can help limit algal growth. To reduce the intensity of algal blooms in the Clark Fork River in western Montana, numeric nutrient standards were put in place that regulated the release of the nutrients nitrogen and phosphorus into the river from wastewater. …

Responses Of Elk To Mangement Actions And Hunter Access In The Northern Sapphire Mountains, Montana, Usa, Peter O. Mumford

Graduate Student Theses, Dissertations, & Professional Papers

Chapter 1

Regulation of rifle hunting of adult female elk is the main tool wildlife managers use to manage the abundance of elk (Cervus canadensis) in the western United States. However, elk are increasingly located in areas where hunting access is restricted during rifle-hunting season, decreasing the ability of managers to reduce elk abundance through hunter harvest. Management actions that restricted hunter access in a 26 km2 area and closed 62 kms of predominantly 2-wheel motorized routes occurred in the northern Sapphire Mountains, Montana, USA. We collected data on elk locations before and two years after the management actions and …

Individual And Population Responses To Hydrologic Variability In A Headwater Stream Salamander, Madaline Cochrane

Graduate Student Theses, Dissertations, & Professional Papers

Understanding how organisms respond to environmental variability is a central goal in ecology – a goal made even more pressing by the herculean challenge global climate change presents to all organisms. Climate change is increasing the frequency and intensity of floods and droughts, which will likely have disproportionate effects on freshwater organisms. Many stream-associated species have multi-stage life histories. However, we lack an empirical understanding of life history and movement responses of these organisms to hydrologic disturbances, and how these responses may influence demographic rates. In my dissertation, I used a combination of growth, developmental, movement, and demographic data to …

Genetic And Environmental Contributions To Wolbachia-Induced Cytoplasmic Incompatibility, Kelley Van Vaerenberghe

Graduate Student Theses, Dissertations, & Professional Papers

Maternally-transmitted Wolbachia infect the cells of most insect species, but their frequencies in host populations vary. While much of their success can be attributed to their ability to manipulate host reproduction, these manipulations are context-dependent, varying due to several biotic and abiotic factors. Wolbachia’s most common manipulation, cytoplasmic incompatibility (CI), is a conditional sterility phenotype where male-female host compatibility depends on their infection status. Specifically, CI occurs when infected males produce modified sperm that cause increased embryonic lethality unless the female carries a similar infection. Rescuing their eggs from CI increases the relative fitness of infected females, promoting Wolbachia spread …

Seedy Business: Unveiling Fruit-Frugivore Interactions In Loango National Park, Gabon, Diandra Mary Lewis

Graduate Student Theses, Dissertations, & Professional Papers

Fruit-frugivore interactions within forest ecosystems are intricate and are critical determinants of community structure, function, and composition. Increasing anthropogenic impacts on biodiversity in general and forests in particular highlight the need to better understand these plant-animal relationships. This thesis focuses on connections between fruit-bearing plants and the animals that eat their fruits in a relatively undisturbed rainforest in Gabon. The work combines two studies: one scrutinising fruit trait clustering, and the other delving into the difference between using dispersers versus consumers in seed dispersal networks.

In chapter 1, we focused on fruit traits and how they group together in order …

Investigating Intellectual Diversity: A Critical Examination Of Academic Publishing Practices And Their Effects On Wildlife Conservation, Madeline M. Damon

Graduate Student Theses, Dissertations, & Professional Papers

Academic publishing processes and standards play a fundamental role in communicating, reviewing, and expanding scientific knowledge in wildlife conservation. However, various publishing biases privilege some research perspectives and worldviews while limiting others. These biases directly impact intellectual diversity, or differences in ontology, axiology, and epistemology. This study aims to quantify intellectual diversity in the field of wildlife conservation and identify how publishing biases affect knowledge available to researchers and decision-makers worldwide.

The study employed a sample of 50,000 articles published between 2018 and 2022, collected from the Web of Science database. To analyze the vast amount of article records, natural …

Evaluating The Relative Influence Of Soil Water Potential, Soil Moisture, And Vapor Pressure Deficit On Semi-Arid Vegetation Dynamics, Kayla R. Jamerson

Graduate Student Theses, Dissertations, & Professional Papers

Knowledge of vegetation’s response to soil water availability and atmospheric demand is critical to understanding the impact of climate change on semi-arid ecosystems. However, limited field-based research has been conducted to assess the relative importance of these drivers and previous research has simplified the assessment of soil water availability by relying on soil volumetric water content (VWC) as a primary control on plant growth, which, as opposed to soil water potential (Ψsoil), does not account for the effects of soil texture on plant available water. To address these gaps, we compared remotely sensed indicators of vegetation response to field based …

Traditional Ecological Philosophy, Michael J. Desrosier

Graduate Student Theses, Dissertations, & Professional Papers

A collection of creative essays that span a range of topics centered on Indigenous environmental wisdom.

Predicting Mountain Lion Resource Selection And Abundance In North America, William Connor O'Malley

Graduate Student Theses, Dissertations, & Professional Papers

The relationship between habitat quality and density is well documented in lower trophic levels but to what extent it can be extended to higher trophic levels is unknown. I tested the relationship between habitat quality, home-range size and density using a wide-ranging, well-studied, top carnivore, the mountain lion (Puma concolor). First, I created a second-order resource selection function (RSF) for mountain lions in their current North American range using GPS collar data from 476 individuals in 20 study sites and remotely-sensed landscape data. I used the RSF and home range estimates derived from collared animals to quantify mountain …

"Our Loons": Participant Attachments And Motivations Within A Community-Based Monitoring Program, Taylor Tewksbury

Graduate Student Theses, Dissertations, & Professional Papers

Organizations can benefit from understanding person-place relationships and volunteer motivations as they recruit and sustain involvement in their community-based monitoring (CBM) programs. Place attachment, or the bond between people and their meaningful environments, is one lens through which to explore these relationships. Past studies have associated place attachment with environmentally responsible behaviors (ERB), such as CBM involvement. However, few studies have explored the relationship between place attachment and CBM in the context of volunteers’ attachment to the species of study.

The purpose of this research study was to explore the place-based relationships and motivations among volunteers of the Loon Preservation …

How Aquatic Insects Mitigate Temperature-Oxygen Challenges Via Behavioral, Morphological, And Physiological Plasticity, Jackson H. Birrell

Graduate Student Theses, Dissertations, & Professional Papers

How do organisms respond to environmental challenges and to environmental change? These questions occupy a central place in ecology and answering them will help us to understand why species live where they do, how organisms are affected by human activities, and, ultimately, how to choose among alternative conservation strategies. These questions are difficult, however, for two reasons. First, environmental challenges often involve multiple, interacting stressors. Second, individual responses can be modified by behavioral, morphological, and physiological plasticity. My dissertation investigates how interactions between temperature and oxygen influence the performance and survival of aquatic insects and how plasticity allows individuals to …

An Integrative Investigation Of The Synechococcus A/B Clade During Adaptive Radiation At The Upper Thermal Limit Of Phototrophy, Christopher L. Pierpont

Graduate Student Theses, Dissertations, & Professional Papers

Thermophilic microorganisms have been scientifically observed since the early nineteenth century and have spurred many questions about the limits of life and the capacity of organisms to survive extreme conditions. Decades of research on thermophile proteins and genomes have yielded several proposed correlates of temperature that may contribute to adaptation of bacteria and archaea to high temperature. However, many of the generalizations reported are drawn from analyses of deeply divergent taxa or from individual case studies in isolation from mesophilic relatives. Members of the Synechococcus A/B (SynAB) group are the only cyanobacteria with members able to grow above 65 °C …

Evaluating The Use Of Camera Traps To Monitor Populations Of Ungulate Prey In The Russian Far East, Scott Johnston Waller

Graduate Student Theses, Dissertations, & Professional Papers

Efforts to recover endangered carnivore populations are often limited by insufficient populations of prey. When recovering prey populations, estimates of population density are invaluable metrics to monitor recovery efforts. In Russia, wildlife managers use the Formozov-Malyushev-Pereleshin (FMP) snow tracking method to estimate densities of ungulate prey of the Amur tiger (Panthera tigris). Yet, increasing variability in snow conditions and other challenges have limited its reliability. Camera traps offer a promising alternative approach since managers already use cameras to monitor tigers. However, the assumptions and study design necessary to implement capture-recapture models for tigers are different from those needed …

Invasive Earthworms In The Crown Of The Continent System And Implications For Land Management, Meghan Elizabeth Scott

Graduate Student Theses, Dissertations, & Professional Papers

The United States contains invasive earthworms originating from Europe and Asia; the majority are European lumbricids. Direct introduction occurs primarily through human activity and, once established, earthworm populations are difficult to address. When exotic earthworms engage in bioturbation, they negatively alter subterranean food webs and nutrient cycling by disrupting soil layering systems. The most prominent form of physical alteration is the change and removal of the topmost organic layer. This disruption is associated with altered nitrogen and carbon cycling, as well as altered forest floor plant communities.

The Crown of the Continent ecosystem is located in southwestern Alberta, southeastern British …

Re-Storying Grant Creek: A Case Study Of Relational Dynamics On A Degraded Montana Stream, Seamus Rucci Land

Graduate Student Theses, Dissertations, & Professional Papers

The UN Decade on Ecosystem Restoration began in 2021, and after a history of contentious ethical debates, ecological restoration is increasingly portrayed as a viable framework for combating environmental degradation and supporting more healthy and stable social-ecological systems. The proposed ecological restoration of Grant Creek, a degraded stream near Missoula, Montana, offers an opportunity to connect a restoration site to the broader, rapidly growing field of restoration practice. It also allows the opportunity to forward the ‘relational turn’ proposed by many in the sustainability sciences as an ontological and methodological means to move beyond positivist portrayals of social-ecological systems, which …

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, …

Concentration And Composition Of Nanoparticles And Colloidal Particles In A Mine-Waste Contaminated River, Kaitlin Rose Perkins

Graduate Student Theses, Dissertations, & Professional Papers

Metals and metalloids (metal(loid)s) in aquatic ecosystems are often described through measures of their concentrations in whole and filtered waters. The filtered fraction is operationally defined as “dissolved,” and assumed to be primarily composed of free metal(loid) ions or of ions bound by low molecular weight organic matter. This definition ignores that the dissolved fraction also likely contains colloidal particles (1 to 1000 nm) that can pass through commonly used filters. This colloidal fraction can also be preferentially removed from the water column by algae and other aquatic organisms compared to free metal(loid) ions and organic bound metal(loid)s. Though they …

Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro

Graduate Student Theses, Dissertations, & Professional Papers

Human activities have doubled the rate of nitrogen inputs onto the landscape resulting in elevated nitrogen concentrations in our streams. Anthropogenically applied nitrogen is largely transported to stream networks via groundwater movement. Groundwater discharge occurs in distinct points along a stream but whose influences can often persist far beyond that area due to insufficient biogeochemical removal of imported nitrogen potentially causing alterations in community structure and precipitating large algae blooms. To understand the factors governing nitrogen abundance in a historical polluted stream, I used a mass-balance approach to quantify groundwater-surface water interaction and the magnitude of groundwater nitrogen input and …

Management And Conservation Of Westslope Cutthroat Trout In An Impacted, Connected River System, Troy Weant Smith

Graduate Student Theses, Dissertations, & Professional Papers

Westslope cutthroat trout Oncorhynchus clarkii lewisi (WCT) is a native species of high conservation value that historically exhibited partially migratory behavior throughout its range. Long-term persistence of WCT is threatened by human habitat modification, fragmentation, introduction of non-native species, and hybridization. As a result of these changes, remnant populations in Montana have shifted toward resident populations in headwater systems and away from migratory populations in larger connected river networks. This is compounded by the historic introduction of rainbow trout O. mykiss (RBT) that hybridize with WCT, especially in larger river habitats. Rock Creek in western Montana, USA was historically managed …

Monitoring The Wetland Landscape: White-Faced Ibis (Plegadis Chihi) Breeding Habitat As A Model Assemblage, Shea P. Coons

Graduate Student Theses, Dissertations, & Professional Papers

Wetlands structure landscape biodiversity by providing critical habitat to numerous fish and wildlife species. However, climate change, growing human populations, and shifting land use practices strain limited water supplies that sustain wetlands in the semi-arid western US. Conserving a wetland network with prominent value to wildlife is paramount to ensure future security of habitat and ecosystem processes. Here, I use white-faced ibis (Plegadis chihi; hereafter ‘ibis’) breeding colonies as a model system to identify and monitor a landscape-scale wetland network across the semi-arid western US. Ibis serve an important role in marking ecologically important wetland networks because they require a …

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 …

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 …

Protecting Biodiversity On National Forests: The Evolution And Implementation Of Forest Planning Regulations, Anna Wearn

Graduate Student Theses, Dissertations, & Professional Papers

In 2012, the U.S. Forest Service (USFS) promulgated new forest planning regulations that significantly altered national forest management. One of the most controversial and important advancements was the inclusion of what were meant to be stronger biodiversity protections. An analysis of USFS’s rationale in revising the biodiversity regulations provides insights into how to interpret the substantively and procedurally new ecosystem and species protections. Examining this regulatory history reveals three key changes to the manner in which national forests are required to manage and monitor biodiversity: 1) a greater reliance on science to inform planning, 2) a new emphasis on ecological …

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 …

Food Web Effects Of Lake Trout (Salvelinus Namaycush) Invasion In Northwestern Montana, Charles Wainright

Graduate Student Theses, Dissertations, & Professional Papers

Around the turn of the 20th century, lake trout (Salvelinus namaycush) were widely introduced in several lakes and reservoirs outside their native range in western North America. Since then, lake trout have become problematic in many lakes where they were introduced, causing significant declines in popular sport fishes and native species, most notably federally protected bull trout (Salvelinus confluentus). Despite evidence that invasive fish can cause cascading trophic effects in aquatic communities, the impacts of lake trout introduction / invasion on aquatic food webs remain poorly understood. Moreover, native fish restoration programs tend to focus on suppression …

Decoupled Diel Solutes: Linking Primary Production And Nitrate Uptake In A Montane Stream, Kimberly Bray

Graduate Student Theses, Dissertations, & Professional Papers

Tight coupling of surface water diel dissolved oxygen (DO) and nitrate-N (NO₃-N) signals reflects stoichiometric demand of carbon and nitrogen in stream ecosystems. However, DO and NO₃-N can become decoupled due to alternative drivers of diel solutes, resulting in conflicting estimates of stoichiometric and modeled NO₃-N uptake. In this study, I measured benthic biomass, hydrology, and dissolved solutes in a montane stream located in western MT over a growing season (June-October 2019). Daily stream metabolism and NO₃-N uptake were modeled using a single-station open-channel approach. Timing and amplitude of key diel signals …

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 …

Comparing Fence Modeling And Mapping Approaches To Support Wildlife Management And Research In Southwest Montana, Simon Albert Buzzard

Graduate Student Theses, Dissertations, & Professional Papers

Fences pose significant challenges to wildlife movement, but their effects are difficult to quantify because fence location and fence type data are lacking on a global scale. We developed a fence location and density model in southwest Montana, USA to provide data to researchers and managers, and test whether previous models could be applied to a new region and retain suitable levels of statistical accuracy. Our model used local expert opinion to inform how road, land cover, and ownership spatial layers interacted to predict fence locations. We validated the model against fence data collected on random 3.2 km road transects …

Heat For The Masses: Thermal Ecology Of The Western Tent Caterpillar, Victoria Dahlhoff

Graduate Student Theses, Dissertations, & Professional Papers

A unique feature of some gregarious, colonial insects is their ability to create external structures that alter environmental conditions for the entire (often family) group. A combination of physical alteration of local microhabitats and behavioral thermoregulation allows many of these animals to actively control their body temperatures, which allows them to regulate energy use and metabolism in variable thermal environments. Here I describe mechanisms of microhabitat modification and thermal regulation in the western tent caterpillar, Malacosoma californicum pluviale. Tent caterpillars build communal silk tents, whose temperatures can rise substantially above ambient air temperature. I experimentally manipulated colony sizes and examined …

Resource Selection And Calving Success Of Moose In Colorado, Forest P. Hayes

Graduate Student Theses, Dissertations, & Professional Papers

Across much of North America, moose populations (Alces alces) are declining due to disease, predation, climate, and anthropogenic pressures. Despite this, populations of moose in Colorado have continued to grow. Studying successful (i.e., persistent or growing) populations of moose can facilitate the continued conservation of the species by identifying habitat features critical for moose persistence.

First, I evaluated calving success of moose in Colorado and the impact of willow habitat quality and nutrition. I then estimated the probability of female moose having a calf using repeated observations in a Bayesian occupancy model. I assigned values for dry matter …