Ecology and Evolutionary Biology Commons^™

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 …

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 …

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 …

From Organisms To Ecosystems: Impacts Of Limb Loss And Regeneration On Crayfish Behavior, Luc Arnaud Dunoyer

Theses and Dissertations--Biology

The ability of some organisms to regenerate tissues and organs has fascinated naturalists since antiquity, dating back to the earliest accounts of scientific inquiry with Aristotle in Ancient Greece. Then, Darwin’s theory invigorated some scientists’ dream of stimulating (or reactivating) regenerative capacities in human beings by showing that we are related to highly regenerative organisms. More recently, a renewed interest in discovering the molecular and genetic basis for organ and tissue regeneration has led biologists to focus more specifically on a restrictive set of model organisms.

Although the process of limb regeneration is different between invertebrate and vertebrate organisms, it …

Urban Soil Carbon And Nitrogen Converge At A Continental Scale, Tara Trammell, Diane E. Pataki, Richard Pouyat, Peter M. Groffman, Carl Rosier, Neil D. Bettez, Jeannine Cavender-Bares, Morgan J. Grove, Sharon J. Hall, James B. Heffernan, Sarah E. Hobbie, Jennifer L. Morse, Christopher Neill, Meredith Steele

Environmental Science and Management Faculty Publications and Presentations

In urban areas, anthropogenic drivers of ecosystem structure and function are thought to predominate over larger‐scale biophysical drivers. Residential yards are influenced by individual homeowner preferences and actions, and these factors are hypothesized to converge yard structure across broad scales. We examined soil total C and total δ13C, organic C and organic δ13C, total N, and δ15N in residential yards and corresponding reference ecosystems in six cities across the United States that span major climates and ecological biomes (Baltimore, Maryland; Boston, Massachusetts; Los Angeles, California; Miami, Florida; Minneapolis‐St. Paul, Minnesota; and Phoenix, Arizona). Across the cities, we found soil C …

Developing An Odonate-Based Index For Monitoring Freshwater Ecosystems In Rwanda: Towards Linking Policy To Practice Through Integrated And Adaptive Management, Erasme Uyizeye

Antioch University Dissertations & Theses

Worldwide, the decline of biodiversity in freshwater ecosystems is occurring at an alarming rate, due to anthropogenic threats, which directly impact humans in a variety of ways. Freshwater ecosystems occupy an integral part of political, socio-economic and ecological spheres. Integrated Watershed Management (IWM) and Adaptive Management (AM) conceptual frameworks provide an underpinning holistic platform from which to evaluate the performance of policies and actions on the ground in relation to freshwater ecosystem management. I investigate the extent to which environmental policies and practices embrace IWM and AM frameworks in Rwanda. Furthermore, this dissertation develops an odonate-based ecological monitoring tool, referred …

The Role Of Warm, Dry Summers And Variation In Snowpack On Phytoplankton Dynamics In Mountain Lakes, Isabella A. Olesky, Whitney S. Beck, Roderick W. Lammers, Cara E. Steger, Codie Wilson, Kyle R. Christianson, Kim Vincent, Gunnar Forrest Johnson, Pieter T.J. Johnson, Jill S. Baron

Geology Faculty Publications and Presentations

Climate change is altering biogeochemical, metabolic, and ecological functions in lakes across the globe. Historically, mountain lakes in temperate regions have been unproductive because of brief ice-free seasons, a snowmelt-driven hydrograph, cold temperatures, and steep topography with low vegetation and soil cover. We tested the relative importance of winter and summer weather, watershed characteristics, and water chemistry as drivers of phytoplankton dynamics. Using boosted regression tree models for 28 mountain lakes in Colorado, we examined regional, intraseasonal, and interannual drivers of variability in chlorophyll a as a proxy for lake phytoplankton. Phytoplankton biomass was inversely related to the maximum snow …

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 …

Estimating Evolutionary Volatility In A Maximum-Likelihood Framework, Samuel Warren Tybout

Graduate Theses, Dissertations, and Problem Reports

Evolutionary volatility is a trait that encompasses a clade’s combined capacity for origination and extinction. High volatility increases extinction risk, and declining global extinction rates are thought to be linked to declining volatility. Despite volatility’s scientific importance, there is no standardized way of measuring it. This study provides a new method, derived from a stochastic birth-death model, of estimating evolutionary volatility from fossil data. Simulations indicate that the method produces accurate and precise estimates for large fossil datasets. Analysis of fossil data for five bivalve families (Lucinidae, Mytilidae, Pectinidae, Pholadomyidae, and Veneridae) indicates that diversity projections made from the estimates …

Leaf Angle And Leaf Stomata Responses To Experimental Drought In Quercus Velutina And Acer Saccharum, Brittany Nichole Casey

Graduate Theses, Dissertations, and Problem Reports

The possibility of increased severity and frequency of drought conditions, as a result of global climate variability, greatly complicates our ability to forecast future forest functions such as productivity and carbon sequestration. Assessing how tree species vary in their response to drought can aid in predicting the impact on forest ecosystems as a whole. Throughfall exclusion (TfE) experiments are potentially useful tools to simulate realistic drought conditions within intact forest ecosystems. We employed a TfE experiment during the 2018 growing season within the WV Land Trust’s Elizabeth’s Woods Nature Preserve, near Morgantown, WV, to assess the leaf angle and leaf …

Tree Growth And Water Use Efficiency During The Twentieth Century: From Global Trends To Local Drivers, Justin Michael Mathias

Graduate Theses, Dissertations, and Problem Reports

The frequency and severity of extreme environmental conditions will continue to increase under global environmental change. How terrestrial plants respond to prolonged, and often novel environmental stressors, will have profound impacts on, and feedbacks with, the Earth climate system at local to continental scales. Central to these feedbacks are plant stomata, actively regulated pores on the leaves of plants that act as a control valve over the fluxes of carbon dioxide (CO₂) into the leaf during photosynthesis and water vapor (H₂O) out of the leaf during transpiration. Importantly, changes in stomatal aperture do not affect the …

Evolutionary Genomics Of Dynamic Sex Chromosomes In The Salicaceae, Ran Zhou

Graduate Theses, Dissertations, and Problem Reports

Identifying the sex-determination region (SDR) and other genomic features of sex chromosomes are of great importance in the studies of the evolution of sex. However, the process of accurately identifying the size and location of the SDR is often difficult, even when a genomic sequence is available. This usually is hindered by large repetitive elements and a lack of recombination in the SDR. In this thesis, I assemble sex chromosomes with whole genomic sequencing data, identify SDRs and explore their genomic features in two sister species from the Salicaceae family. I also develop an interpretation of the lability of the …

The Host Gatekeeper: Using The Flagellar Pathway To Understand Symbiont Host Adaptation, Adam R. Pollio

Graduate Theses, Dissertations, and Problem Reports

The acquisition of microbial partners is a strategy used by a diverse group of arthropods to overcome ecological barriers that might normally make certain niches uninhabitable. The unique phylogenetic opportunities attainable from the natural experiment of the Sodalis-allied clade allow for better understanding of how molecular structures evolve through time. Here, we focus on the evolution of the flagellar synthesis pathway, due to its complexity and ability to diverge in response to ecological pressures. We used this molecular pathway and natural experiment to show that normal evolutionary outcomes associated with symbiosis (i.e., genome reduction) do not explain the predicted conservation …

Nitrogen Fertilization Decouples Roots And Microbes In Temperate Forests: Impacts On Soil Carbon And Nitrogen Cycling, Joseph E. Carrara

Graduate Theses, Dissertations, and Problem Reports

Since the start of the industrial revolution the burning of fossil fuels has resulted in enhanced nitrogen (N) inputs into temperate forests through atmospheric deposition. As N is the limiting nutrient for tree growth across most forests, these inputs have generally enhanced above-ground biomass accumulation. However, the impacts of added N on soil carbon storage (C) are less straightforward. While the mean N response across studies is an enhancement of soil C, these results are variable with some studies reporting net C losses. The classic paradigm posits that N enhances soil C through negative effects on fungal decomposers. However, some …

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 …

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 …

The Evolution And Development Of Chiropteran Flight, Emmaline Willis

Honors Theses and Capstones

No abstract provided.

Current Dog Breeding Practices Impacts On Health And Preservation Of Purebred Dogs, Bridget E. Baker

Honors Theses and Capstones

No abstract provided.

Predator-Based Selection And The Impact Of Edge Sympatry On Components Of Coralsnake Mimicry, Lauren E. Wilson

Electronic Theses and Dissertations

Studying warning coloration and mimicry is an effective way to understand predator-driven selection and phenotypic diversity. The presence (sympatry) or absence (allopatry) of a toxic model plays a role in shaping mimetic phenotypes. However, the impact of edge sympatry and allopatry on predation of mimetic phenotypes is not well understood. We studied coralsnake mimicry to test how edge sympatry and allopatry affect predation on mimetic phenotypes. Specifically, we tested 1) if overall attack rates varied with edge sympatry of coralsnakes 2) which color patterns conferred a fitness advantage 3) which specific mimetic signal components are important in driving predatory attacks …

Browntail Moth Research At The University Of Maine: A Report Of Activities And Findings 2016-2020, Eleanor Grodon, Karla Boyd, Hye Weon Hwang, Barbra Cole, Angela Mech

General University of Maine Publications

The browntail moth has become a very serious problem for many communities in southern, midcoast and central Maine over the past several years as this insect has reached populations levels that we have not seen in 80 to 100 years. Researchers at the University of Maine have teamed up with entomologists in the Maine State Department of Agriculture, Conservation, and Forestry Maine Forest Service (MDACF) to track the spread and investigate the causes of the outbreak and evaluate management strategies for this daunting pest.

The report was prepared by Prepared by: Dr. Eleanor Groden, Professor of Entomology, Emerita, School of …

Pacific Northwest To New England: Exploring The Intersections Of Invasive Ecology, Forest Management, And Alternative Energy, Alexandra N. Neidermeier

Graduate College Dissertations and Theses

Invasive species exact important ecologic, economic, and cultural tolls in forests. This research focused on the intersections of invasive ecology, forest management, and a forest commodity. Invasive ecology was explored through an assessment of two potential biological control agents of hemlock woolly adelgid. The two species of silver fly (Leucopis spp.) from the Pacific Northwest were first examined for temporal resource partitioning patterns. The niches of these species were then examined spatially by developing a species distribution model. Leucopis spp. exhibited sinusoidal patterns of daily emergence when examined over a 29-day period, with peak daily abundances that were inversely related. …

The Environmental Microbiome In A Changing World: Microbial Processes And Biogeochemistry, Stephanie Juice

Graduate College Dissertations and Theses

Climate change can alter ecosystem processes and organismal phenology through both long-term, gradual changes and alteration of disturbance regimes. Because microbes mediate decomposition, and therefore the initial stages of nutrient cycling, soil biogeochemical responses to climate change will be driven by microbial responses to changes in temperature, precipitation, and pulsed climatic events. Improving projections of soil ecological and biogeochemical responses to climate change effects therefore requires greater knowledge of microbial contributions to decomposition. This dissertation examines soil microbial and biogeochemical responses to the long-term and punctuated effects of climate change, as well as improvement to decomposition models following addition of …

Consumption Of Microplastics Impacts The Growth And Fecal Properties Of The Marine Copepod, Acartia Tonsa, Emily Ann Shore

Graduate College Dissertations and Theses

Microplastics (mm) are ubiquitous in the global environment and are increasingly recognized as a biological hazard, particularly in the oceans. Due to the small and pervasive nature of these particles, zooplankton have been known to consume and egest microplastics. Though zooplankton play critical roles in marine food webs and in carbon storage through carbon rich fecal pellets, we know little about the effects of microplastics on early life stage growth, reproductive output, and carbon storage. Here, I investigated the effects of ingestion of low-density Polystyrene beads (5 µm) by the copepod Acartia tonsa on (1) early life stage (naupliar) growth, …