Other Ecology and Evolutionary Biology Commons^™

Anthropogenic Influences On The Decline, Restoration, And Eco-Evolutionary Dynamics Of Lake Superior’S Coaster Brook Trout, Austin Johnson

Dissertations, Master's Theses and Master's Reports

The coaster brook trout is a life history variant of the brook trout (Salvelinus fontinalis) that is characterized by either lake residency or migration between stream and lake habitats. Coaster brook trout were once widespread throughout Lake Superior and its tributaries, but populations declined sharply in the late 19^th and early 20^th centuries. Historically, brook trout were a popular target of recreational and subsistence fishing in the Lake Superior basin, and it has been hypothesized that angling pressure combined with multiple forms of industrial development are what drove the coaster brook trout’s decline. In the mid …

The Decline Of Lake Superior's Woodland Caribou: A Historical Gis Analysis, Jordan W. Kelley

Dissertations, Master's Theses and Master's Reports

Lake Superior’s woodland caribou have been declining since the early 1800s. This thesis asks: why? We hypothesize that as settlers expanded into the region, industrial development in woodland caribou habitat reduced woodland caribou persistence. Using an Historical Geospatial Information System (HGIS) analysis, we find that historical mining and railroad infrastructure are associated with woodland caribou extirpation, while wetlands and protected areas are associated with caribou persistence. We also conducted a stakeholder synthesis of the region to help understand diverse perspectives within and between advocacy coalitions that take different positions on the most effective caribou restoration policies. Beliefs on recovery options …

Avian Haemosporidian Blood Parasite Diversity, Prevalence, And Distribution In Michigan’S Western Upper Peninsula, Maria M. Ferrer

Dissertations, Master's Theses and Master's Reports

Avian haemosporidian parasites, known as avian malaria (phylum Apicomplexa) can diminish an individual bird’s fitness by causing parasitemia, anemia, and reduced survival. Climate change is predicted to increase the spread of malarial parasites into more northerly latitudes where little is known about community compositions of these parasites. I assessed the prevalence and diversity of haemosporidian parasites in the first-ever community-level sampling of malaria in songbirds across the western Upper Peninsula of Michigan. In total, 179 blood samples were collected from birds representing 17 species, at five locations in the Upper Peninsula, including a mature forest, an early successional forest, and …

Effects Of Dissimilar Silvicultural Techniques On Small Mammal Communities In Michigan's Upper Peninsula, Breanna R. Gusick

Dissertations, Master's Theses and Master's Reports

Small mammal populations, and predators reliant upon them as food resources, are often challenged by conflicting objectives of timber production and maintenance of quality habitat. With over 70% of the landscape forested, and nearly one-third of the land privately owned, Michigan’s Upper Peninsula (UP) is a matrix of independent management strategies. To assess the effects of various silvicultural regeneration methods on small mammal populations in the Upper Peninsula, we trapped small mammals in experimental silviculture plots, whereby treatments varied by regeneration method (amount of residual canopy cover) and site preparation (i.e., control, tip-up, and scarification), and deer exclosures. We used …

Applications Of Machine Learning In Microbial Forensics, Ryan B. Ghannam

Dissertations, Master's Theses and Master's Reports

Microbial ecosystems are complex, with hundreds of members interacting with each other and the environment. The intricate and hidden behaviors underlying these interactions make research questions challenging – but can be better understood through machine learning. However, most machine learning that is used in microbiome work is a black box form of investigation, where accurate predictions can be made, but the inner logic behind what is driving prediction is hidden behind nontransparent layers of complexity.

Accordingly, the goal of this dissertation is to provide an interpretable and in-depth machine learning approach to investigate microbial biogeography and to use micro-organisms as …

The Effect Of Seasonality On Yellow Perch Ecology And Ecotoxicology Within Lake Manganese, Bailey Duxbury

Dissertations, Master's Theses and Master's Reports

Seasonality is a consistent component of aquatic ecosystems yet most fish biological and ecotoxicological studies commonly employ field sampling protocols focused during the warm open water season with minimal emphasis placed on winter sampling, especially for north-temperate latitude ecosystems. Such strategies limit our understanding of poikilotherm biology and ecology during the overwintering seasons. Here, I investigated seasonal changes in yellow perch (Perca flavescens) biology, ecology and ecotoxicology over a one-year period in Lake Manganese. Significant seasonality was observed for metrics including fish energy densities (kJ/g), gonadosomatic indices, whole-body lipid contents, and carbon stable isotope values (δ¹³C). …

Examining Aspen Expansion From Before And After Prescribed Burning In A Native Fescue Grassland Through Geospatial Techniques, Christopher Anderson

Dissertations, Master's Theses and Master's Reports

Native fescue (Fescue spp.) grasslands of the Intermountain West have become increasingly scarce due to the advent of modern agriculture, the loss of Indigenous people’s land management practices, modern wildfire management and the extirpation of bison (Bison bison bison). Native grassland is a biodiversity hot-spot, is significant for carbon sequestration, and essential to many species of flora and fauna that occur in the ecosystem. Our study site, on the Rocky Mountain Front in Waterton Lakes National Park, Alberta Canada, consists of 30 discrete aspen stands (Populous tremuloides) which are encroaching on this declining shortgrass fescue …

Ecological Implications Of Foraging And Life-History In Three Cold-Adapted Species, Andrew Von Duyke

Dissertations, Master's Theses and Master's Reports

This research investigates the ecology of: ringed seals (Pusa hispida), moose (Alces alces), and bowhead whales (Balaena mysticetus). Each of these species draws upon specialized strategies to meet the physical demands of life in their extreme environments. However, they are currently experiencing unprecedented changes in their habitats. This work adds to what is known about the behavior, physiology, and population dynamics of cold-adapted species—providing insights of value for an improved understanding of foraging and life-history theory, and informing conservation and ecosystem monitoring efforts. Chapter 1 provides a brief introduction to the scope of work …

The Dynamic Nature Of Forage Preference And Microhistological Atlas, John J. Henderson

Dissertations, Master's Theses and Master's Reports

Moose, Alces alces, are among the most iconic species in the northern circumpolar temperate forests. Multiple factors influence moose density. Winter is a time of severe dietary stress for moose because deciduous trees are leafless and available forage is limited to conifers with high plant secondary metabolites or low-energy deciduous twigs. Forage preference depends on the intrinsic forage properties, abundance of forage and environmental stressors. These stressors include predation risk and severity of climate that affect forage efficiency. We examined forage preference of moose on Isle Royale National Park during winter over a ten-year period. Diet was divided into …

Associations Between Invasive Eurasian Watermilfoil And Littoral Fish And Invertebrate Communities In The Keweenaw Waterway Of Lake Superior, Carmen Leguizamon

Dissertations, Master's Theses and Master's Reports

The invasion of Eurasian watermilfoil (Myriophyllum spicatum) can influence littoral zone communities within lakes. Its formation of dense mats at the water surface can suppress native macrophyte growth and impact fish diets and community structure, as well as invertebrate assemblages. However, in the colder waters of the upper Great Lakes region, Eurasian watermilfoil is patchily distributed and integrates more with the native macrophyte community. In order to identify the associations of invasive Eurasian watermilfoil and the littoral communities of the Keweenaw Waterway of Michigan’s Upper Peninsula, we sampled invertebrates, fish, and macrophytes at sites that represented a gradient of Eurasian …

Carbon Flux Dynamics In High Altitude Peatlands In The Ecuadorian Andes, Maria Elisa Sanchez Garces

Dissertations, Master's Theses and Master's Reports

Although knowledge of peatland CH₄ and CO₂ exchange in temperate mountain ecosystems is available, information about carbon (C) exchange in peatlands of the Andean mountains is limited and these ecosystems may behave differently given the particular characteristics of the Andean tropics. These ecosystems are highly productive and under pressure by grazing. Our first objective was to measure baseline carbon dioxide (CO₂) and methane (CH₄) flux in an undisturbed peatland in Cayambe-Coca National Park. Our second objective was to quantify CO₂ and CH₄ fluxes in an intensively cattle grazed peatland near Antisana Ecological …

Observations Of Hippopotamus H. Amphibius In The Little Scarcies River Of Sierra Leone And Arguments For Their Conservation Based On Roles They Play In Riverine Grasslands And Nutrient Loading, Lindsey R. Perry

Dissertations, Master's Theses and Master's Reports

A small population of Hippopotamus amphibius remains in Sierra Leone and conservation efforts may be needed to support the Hippos and their indirect benefits to fisheries and grassland production. The hippo is a known ecosystem engineer, and a potentially important contributor of nutrients to the river systems they inhabit supporting the food web and local fisheries. In this study I observed hippos in the Little Scarcies River and uplands of the Outamba-Kilimi National Park to estimate their numbers and ultimately their potential input of nutrients into the river. Hippos forage at night in grasslands neighboring rivers, removing up to 3.62 …