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The Decline In Monarch Butterfly, Danaus Plexippus, Populations: An Example Of The Global Threat To Biodiversity, Olivia Sidoti

Honors Projects

Biodiversity encompasses the variety of all life on Earth and how these aspects of nature interact with each other. To have stable and abundant biodiversity, vast amounts of species and organisms are required within an ecosystem. As a result of the increase in negative impacts of human activities and behaviors on the health of nature, biodiversity has been decreasing. An example of the decrease in biodiversity is depicted by the recent decline of the monarch butterfly species. The monarch butterfly is an iconic North American insect that is experiencing a decline in its population due to threats such as deforestation, …

Colombia´S National Mountain Peatland Map: Peatland Distribution, Condition And Carbon Stocks, Patrick Nicolas Skillings-Neira

Dissertations, Master's Theses and Master's Reports

In this research, I explore the distribution, condition, and carbon stocks of peatlands in the Colombian Andes. High mountain peatlands in Colombia, usually found within the páramos, face significant ecological challenges. Although Law 1930 (2018) mandates sustainable páramo management, it does not prohibit peatland disturbance. Undisturbed peatlands act as long-term carbon sinks, but their degradation can convert them into greenhouse gas sources. The lack of comprehensive national peatland mapping hampers effective environmental management and policy formulation. I aim to create a national-scale peatland map, assess peatland distribution, quantify degraded pasture peatlands, and report preliminary soil carbon stocks. Additionally, I compared …

Better Understanding The Barred Owl, Adam Lee Potts

Graduate Student Theses, Dissertations, & Professional Papers

This thesis research presents an analysis of barred owl nest site selection in an understudied region of their expanded range. The barred owl has dramatically expanded its range westwards over the last 150 years, prompting multiple conflicting reinterpretations of their species account. Hypotheses of range expansion are reviewed to provide context for this study’s research. This study gathers empirical data on nest site selection in the mixed conifer forests of Montana’s Seeley-Swan and Mission Valleys. Eight barred owl nests were located following extensive territory surveys. Field measurements of tree height and diameter using USFS Forest Inventory and Analysis (FIA) plot …

Variations In Thermoregulation Strategies Of Northern And Southern Populations Of Mischocyttarus Mexicanus, Taylor Guild

Honors Theses

Mischocyttarus mexicanus is a species of eusocial paper wasp that is found across much of the Southeastern coastal region of the United States. Contrasting wintering strategies have been seen in northern versus southern populations. Anecdotally, northern populations overwinter by clustering on top of palmetto fronds, their preferred nesting substrate, in a sort of "taco" shape, while southern populations stand on their nests that hang on the underside of the palmetto frond throughout the year. I tested three hypotheses related to the adaptive value of northern over-frond clustering behavior: 1) Over-frond clustering is thermoregulation related, meaning it would be temperature driven. …

The Long-Term Effects Of Wildfire Severity On Oak-Pine Communities And Their Microclimates, Scott Glenn Culbert

Theses and Dissertations--Forestry and Natural Resources

In the eastern U.S., fire-dependent tree species have historically dominated upland forest communities, but are now experiencing widespread regeneration challenges as a result of 20^th century fire suppression policies, and are being replaced by mesophytic species. Wildfires that contain areas of high burn severity may provide an important means of mitigating these challenges and facilitating fire-dependent species regeneration and recruitment into larger size classes. One mechanism by which high-severity fire can accomplish this is by modifying understory microclimate characteristics to be more conducive to these species’ growth. A wildfire within the Daniel Boone National Forest, Kentucky, USA, provided the …

Host And Symbiont-Specific Patterns Of Gene Expression In Response To Cold Stress In The Temperate Coral Astrangia Poculata, Kellie Navarro

Honors Projects

The coral Astrangia poculata inhabits hard-bottom environments from the Gulf of Mexico to Massachusetts and withstands large seasonal variation in temperature (–2 to 26 °C). This thermal range and its ability to live in a facultative symbiosis makes this species an ideal model system for investigating stress responses to ocean temperature variation. Although it has been shown that aposymbiotic A. poculata upregulates more genes in response to cold stress than heat stress, the transcriptomic response of the holobiont (coral host and symbiotic algae) to stress is unknown. In this study, we characterize changes in gene expression in both the host …

Advancing Assessments Of Climate Change Vulnerability Of West Virginia Watersheds, Joseph T. Molina

Graduate Theses, Dissertations, and Problem Reports

As climate change is becoming increasingly recognized as a threat to aquatic ecosystems, climate adaptation planning, in both the long- and short-term, is becoming more common in natural resource management. There is a need within conservation agencies to develop methodologies and assessments that support adaptation planning to efficiently disperse conservation dollars and effectively strengthen ecological and community resilience as climate changes continue. My thesis aims to provide West Virginia natural resources managers with climate vulnerability assessments that can be used to determine where and how conservation efforts should be administered. Additionally, I demonstrate a methodology that can be built upon …

Quantifying The Effect Of Disturbance On Native Mojave Desert Shrubs, Tamara J. Wynne

UNLV Theses, Dissertations, Professional Papers, and Capstones

Disturbance can come in many different forms. In our studies, we looked at the impact of a solar photovoltaic facility on native plants growing inside and outside of the facility, alteration in precipitation (simulated) on four native shrubs and the impact of applying supplemental water as a function of volume and frequency to establish native shrubs such as might occur at restoration sites. Disturbance is becoming a more common phenomenon in many ecosystems throughout the world, increasing the need for studies that quantify the impact at the plant and ecosystem level. Each research project revealed different plant responses, such as …

Avian Species Distribution Models: Using Location Data To Inform Management Decisions, Marilyn E. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Both state and federal wildlife agencies strive to conserve and protect wildlife and their habitats as an important public resource. Applied management decisions often rely on being able to obtain data that can efficiently and effectively enhance the understanding of these systems for informing management actions. Wildlife managers often focus efforts on a small subset of species from an ecosystem, typically called focal species, who can serve as surrogates for understanding the health and function of the system. Models that consider how these focal species interact with the ecosystem are often used to better understand important aspects of their life …

The Influence Of Temperature And Body Size On Food Consumption In Prairie Lizards (Sceloporus Consobrinus), Morgan Pelley

Biological Sciences Undergraduate Honors Theses

Understanding the effect of temperature on physiological and digestive processes, such as voluntary consumption rate, is critical for assessing the impact of climate change. Food consumption is required for lizard survival and reproduction and its rate is dependent on temperature. For ectotherms, as temperatures increase, the amount of food consumed to meet the energy requirements related to survival and reproduction must also increase. Information on the amount of food voluntarily consumed may aid in determining if lizards can meet energy requirements. Such information could also aid in predicting survival of lizard populations, through construction of predictive climate change models. In …

Climate-Driven Selection Results In Powerful Geographic Framework For Predicting Phenotype, Alexandra Neild

Masters Theses

Our ability to prepare for and mitigate the likely ecological and evolutionary impacts of climate change largely depends upon our ability to predict the phenotypic responses of organisms that allow them to persist, adapt, and migrate along environmental stress gradients. Using fifteen populations of cottonwoods, a dominant riparian forest tree, that are distributed along elevation gradients and represent three genetic provenances, we hypothesized and show that: 1) populations within a provenance demonstrate parallel evolutionary responses to climatic gradients associated with elevation; and 2) the evolutionary effects of elevation on bud-break phenology varied by provenance. Across all populations, we find strong …

Blue Mussel Hybrid Complex Shifts In The Gulf Of Maine Towards A Dominance Of Mytilus Edulis, Daniel Woods

Honors Program Theses

The Gulf of Maine (GOM) in the United States is the fastest warming body of water in the world. Due to a complex history of glaciation, the GOM has restricted circulation that causes it to function more akin to an enclosed sea. As climate change has disrupted the stable flow of the Gulf Stream, more warm-water currents are entering the GOM at higher frequency. This warming has had a profound impact on the distribution of the blue mussel, Mytilus spp., which inhabits the rocky intertidal habitat within the GOM as the main prey species to a keystone predator. Two sister …

Mitigation Of Negative Effects Of Ocean Change On Oysters By Eelgrass And Its Implications For Aquaculture In Midcoast Maine, Fiona G. Ralph

Honors Projects

Species interactions are important to organisms and to the ecosystems they inhabit. These interactions, sometimes facilitations, can result in increased resiliency for both species. When facilitation occurs, organisms co-assist with physiological and environmental stressors. As anthropogenic impacts become more stressful for modern organisms, these interactions could offer a solution for many species. Ocean acidification has been shown to be detrimental to many calcifying organisms including oysters. More acidic conditions can slow the process of shell calcification, which can slow growth rates. This effect could directly impact the robust oyster farming business in Midcoast Maine. Because of its possible importance to …

The Impact Of Tidal Elevation And Climate Change On The Growth And Performance Of Balanus Glandula, Sam Martin

Pitzer Senior Theses

Tidal elevation affects the survival, growth, and performance of intertidal organisms because it regulates their exposure to heat, waves, food availability, and a variety of other abiotic factors. While previous research has explored the relationship between temperature and the performance of the barnacle Balanus glandula, there are unanswered questions about how tidal elevation affects B. glandula performance and growth. I compared the growth of B. glandula at three tidal elevations in Friday Harbor, Washington, and estimated the metabolic cost of emersion at each tidal elevation using a cost equation gained from thermal performance curves and average daily maximum temperatures. …

Assessing Chemical And Biological Recovery From Acid Rain Deposition In Montane Vermont Lakes, Sydney Diamond

Graduate College Dissertations and Theses

Vermont’s inland lakes are changing rapidly in response to anthropogenic disturbance pressures. While changes in water chemistry are well documented across the state, the biological response of primary producer communities to these shifts remains poorly understood. This project investigated the response of phytoplankton communities to the interacting effects of recovery from acidification and climate change in high-altitude lakes. We analyzed long-term monitoring and meteorological data in four of Vermont’s acid-impaired lakes and found that as pH and acid-neutralizing capacity has increased, so have concentrations of dissolved organic carbon (DOC) in most lakes. To assess the biological response to these processes, …

Responses Of Juvenile Atlantic Salmon To Competition And Environmental Change: Implications For Performance In Maine Streams, Nicole C. Ramberg-Pihl

Electronic Theses and Dissertations

New England’s climate is changing faster than that of any other region in the continental United States. Over the last century, Maine has experienced an increase in annual temperature of approximately 1.48^oC along with a 15 percent increase in annual precipitation. Temperature and precipitation play vital roles in shaping the ecology of freshwater environments. Therefore, changes in regional climate could undermine the structure and stability of Maine’s freshwater systems as they currently exist.

Maine currently harbors the last wild populations of Atlantic salmon (Salmo salar) in the United States. Atlantic salmon were once abundant in Maine …

A Tale Of Two Species: Black-Tailed And White-Tailed Prairie Dog Biogeography From The Last Interglacial To 2070, April Dawn Bledsoe

Electronic Theses and Dissertations

Ecological niche models (ENMs) were created for White-tailed and Black-tailed prairie dogs and projected into the Last Interglacial (LI), the Last Glacial Maximum (LGM), and mid-Holocene (mid-H) to discern possible past suitable habitat for both species. Additionally, ENMs were projected into the future year 2070 representative concentration pathways (RCPs) 2.6 and 8.5 to discern how climate change may affect future habitat suitability. Kernel density estimations, minimum convex polygons, and median distribution centers of White-tailed and Black-tailed occurrence records were examined between time-periods to discern the effects of anthropogenic westward expansion on both species’ distributions. Current ENMs were constructed from commonly …

Bee Abundance Along A Tropical Montane Elevational Gradient And Implications For Crop Pollination Services, Kristin M. Conrad

Online Theses and Dissertations

Tropical forests are among the biologically richest ecosystems on Earth, but how most organisms in these forests will respond to a warming climate remains uncertain. Insects are expected to be highly responsive to climate change due to their short life cycles that are strongly influenced by temperature. Plants depend on pollinators to set seed and reproduce, and many animal populations rely on the resources provided by flowering plants. There is an urgent need to document elevational distributions and thermal specialization for tropical bee species to understand how these important pollinators may respond to warming temperatures. My four-year study (2016-2019) aims …

Habitat Stability In Appalachian Headwater Systems And Potential Impacts On Brook Trout Populations, Zac F.W Zacavish

Graduate Theses, Dissertations, and Problem Reports

The impact climate change will have on the habitat for Brook Trout (Salvelinus fontinalis) could directly impact key demographic characteristics. Traditionally, broad-scale studies of climate change effects on the family Salmonidae focus on the thermal shifts predicted over the next century. While some studies shed light onto other variables such as biotic interactions, flow regime, and disturbance, the significance of the climate-trout interaction is not always observed. With the high degree of influence climate cycles can have on habitat and channel morphology, this study aimed to highlight temporal habitat shifts to begin addressing climate-habitat interaction. By studying habitat distribution …

Ecology And Conservation Of Shrubland Bird Communities In The Eastern Ghats Of Indi, Anant Deshwal

Graduate Theses and Dissertations

Anthropogenic disturbance, in its multiple facets represents a major threat to biodiversity and habitat quality. Consequently, extensive research is guided towards understanding anthropogenic disturbance and their effects on wildlife for development of wildlife management plans. However, for development of effective wildlife management plans it is imperative that we understand the habitat use and preference by local fauna along with effects of anthropogenic presence. In this dissertation, I studied the habitat usage and preferences of Shrubland birds in the Eastern Ghats of India during the pre-monsoon and post monsoon seasons. Eastern Ghats show a marked difference from pre-monsoon season to post-monsoon …

Projected Sea Level Rise And The Conservation Ecology Of The Micronesian Megapode (Megapodius Laperouse Senex) In Palau, Micronesia, Paul M. Radley

Theses: Doctorates and Masters

Climate change has been a subject of numerous studies. While findings suggest that most biological taxa will be affected by its manifestations, aspects of a species life history may increase its susceptibility to climate change. Given their reliance on environmental sources of heat to incubate their eggs, I examined the vulnerability to climate change of the avian family Megapodiidae. I also assessed habitat use, susceptibility to sea level rise, and the effect of introduced rats and tourist presence, as added stressors to climate change, on the Micronesian Megapode (Megapodius

laperouse senex) in Palau.

Based on available literature, I …

Effects Of Climate Variability: A Long-Term Perspective On Leaf Litter Processing In The Ogeechee River, Jose A. Sanchez

Electronic Theses and Dissertations

The Intergovernmental Panel for Climate Change (IPCC) predicts a rise in temperatures and changes to precipitation patterns for the 21^st century. These changes are expected to lead to a higher frequency of extreme events such as drought and floods which lead to the alteration of the hydrology, communities, and processes of freshwater ecosystems. Leaf litter decomposition in stream ecosystems is an important component of the energy and nutrient cycle representing a food source for aquatic organisms. This has made it a tool for assessing long term responses to disturbance due to changes in the assemblage of macroinvertebrates that …

Climatic Range Filling Of North American Trees, Benjamin Seliger

Electronic Theses and Dissertations

Understanding the degree to which species distributions are controlled by climate is crucial for forecasting biodiversity responses to climate change. Climatic equilibrium, when species are found in all places which are climatically suitable, is a fundamental assumption of species distribution models, but there is evidence in support of climate disequilibria in species ranges. Long-lived, sessile organisms such as trees may be especially vulnerable to being outpaced by climate change, and thus prone to disequilibrium. In this dissertation, I tested the degree to which North American trees are in equilibrium with their potential climatic ranges using the ‘range filling’ metric, which …

Potential For Climate Induced Methane Hydrate Dissociation, Graham Macwilliams

Pomona Senior Theses

Methane hydrates are frozen deposits of methane and water found in high pressure or low temperature sediments. When these deposits destabilize, large quantities of methane can be emitted into the atmosphere. This is significant to climate change because methane has 25 times more greenhouse gas potential than Carbon Dioxide. Worldwide, it is estimated there are between 2500 and 10000 gigatons of methane stored in hydrate deposits. This represents more carbon than all fossil fuels on Earth. It is estimated that between 200 and 2000 gigatons of methane are stored in hydrates in Arctic waters acutely vulnerable to greenhouse warming. Over …

Habitat Ecology, Trophic Interactions, And Distribution Of Endangered Himalayan Musk Deer In The Nepal Himalaya, Kapil Kishor Khadka

Graduate Theses and Dissertations

This dissertation seeks to explore and assess the habitat selection, trophic interactions and distribution of Himalayan musk deer. Chapter one deals with seasonal diet analysis of musk deer along with the overlap in consumption with livestock during summer. Microhistological technique was employed to assess dietary consumption. Results showed that Abies spectabilis, Pinus wallichiana, and Berberis species constituted the major portion of musk deer’s diet. Dietary breadth measured by the Shannon index was found higher in winter compared to summer. Although musk deer and livestock shared a considerable number of plant species in their diets, the consumption however was significantly different …

Interactive Effects Of Flow Regime, Climate Change, And Angler Harvest On Smallmouth Bass At The Southern Range Extent, Christopher Middaugh

Graduate Theses and Dissertations

The Ozark-Ouachita Interior Highlands of Arkansas, Oklahoma, and Missouri are the southern extent of native Smallmouth Bass Micropterus dolomieu range. Smallmouth Bass are an important species economically and ecologically, but it is unknown how climate change may affect them in this region and in particular how Smallmouth Bass may be affected differently across streams from various flow regimes. Here I present three projects investigating how climate change, flow regime, and angler harvest may interact to affect Smallmouth Bass over the coming century. I first modeled present and future water temperatures and calculated growth rate potential for Smallmouth Bass from streams …

Effects Of Wildfires On Tree Establishment In Conifer-Dominated Boreal Forests In Southern Northwest Territories, Kirsten Reid

Theses and Dissertations (Comprehensive)

Black spruce (Picea mariana) and jack pine (Pinus banksiana) both release a large majority of their seeds after fire and thus experience large pulses of recruitment during these punctuated events. Global warming is driving intensification of the wildfire regime in the boreal forest, which is resulting in shifts from coniferous to deciduous dominated forests in some parts of the boreal forest of North America. This shift can present consequences for forest structure, ecosystem dynamics, carbon cycling, and wildlife habitat.

During 2014, the Northwest Territories experienced a historically unprecedented fire year with 3.4 million hectares of forest …

Flight Of The Freshwater Fish, Michael H. Wilson

Capstones

Michael H. Wilson

Capstone Abstract

December 27, 2016

Flight of the Freshwater Fish

The Hudson River provides for millions of people as a path for commercial and private transportation, a source of food and energy, and perhaps most importantly for many living in the tri-state area as a destination for recreation and relaxation. The most overlooked feature of the river is how the wildlife shows clear signs of a changing climate and rapid environmental response to the impacts of global warming on the river.

Entire populations of fish species in the lower Hudson have been forced to leave the river …

Evolutionary Potential Of A Dispersal-Restricted Species In Response To Climate Change, Lorena Torres Martinez

Open Access Dissertations

Habitat replacement and fragmentation associated with projected climate change pose a critical threat to global biodiversity. Edaphically limited plant species with restricted dispersal abilities will be especially handicapped to track their optimal climate spatially. Instead, the persistence of these species will depend on their capacity to adapt in situ to novel climate regimes. Here I evaluated the evolutionary potential of Lasthenia fremontii, an annual plant species restricted to ephemeral wetlands called vernal pools in California to adapt to the projected patterns of climate change. Across L. fremontii distribution there is a latitudinal gradient in precipitation which, combined with reduced …

Preserving Biodiversity For A Climate Change Future: A Resilience Assessment Of Three Bay Area Species--Adenostoma Fasciculatum (Chamise), Arctostaphylos Canescens (Hoary Manzanita), And Arctostaphylos Virgata (Marin Manzanita), Alison S. Pollack

Master's Projects and Capstones

Anthropogenic climate change is an undeniable threat to the future of the natural world and human civilization. These shifts will have profound impacts on vegetation, especially for species endemic to isolated regions or sensitive to climate change factors. However, species resilience can predict success into the next century. Resilience is defined as the ability to withstand climate change factors, whereas vulnerability is defined as susceptibility to climate induced stress or damage.

Chaparral and coastal scrub ecosystems within the Bay Area of California provide a unique context for examining resilience, as many species are adapted to high temperatures, drought, and wildfire—all …