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Warming Up: Climate Change Related Shifts Of Mycorrhizal Fungal Communities In High Latitude Ecosystems, Megan Rae Devan

Biology ETDs

This dissertation examines how climate change affects mycorrhizal fungal communities in boreal and arctic ecosystems. In chapter one, I revealed that increases in fire severity and related increases in deciduous tree dominance result in greater Ascomycota relative abundance (RA) and subsequent declines in Basidiomycota RA. In chapter two I analyzed the effects of post-fire mycorrhizal fungal communites on host growth. There were trends at the fungal genus level that were largely reflected at the guild level across all hosts; however, there were some fungal genera that had the opposite effect on different host species. In chapter three, I found host …

Effects Of Forest Management On Densities And Nest Survival Of Breeding Birds In Upland Hardwood Ecosystems, Michael Barnes

Electronic Theses & Dissertations

Over the past 50 years, significant declines in 47% of Neotropical migrant bird species have been documented in North America. Declines are most likely due to the loss and fragmentation of breeding, wintering, and stopover habitat mainly caused by agriculture and urban development. This loss of critical habitat results in population sinks that need to be maintained by immigration from a population source found in continuously forested landscapes. However, in landscapes harvested for timber, forest management practices alter the landscape and as a result, affect breeding bird abundances and nest success. The objective of our study was to determine the …

Biogeographical Implications Of Climate Change For An Alpine Mammal, The American Pika, Marie Louise Westover

Biology ETDs

Anthropogenic climate change has already impacted a majority of species globally. The aim of this dissertation is to understand how climate and climate change influences animal ecology and evolution across space and time, using the American pika (Ochotona. princeps) as a model system. I investigate how pika body size, diet, and occupancy are influenced by different aspects of climate over space and time. Body size in O. princeps populations best correlates to precipitation and vegetation, rather than temperature. Our findings suggest that pika body size may be more related to vegetation and food availability than the direct effects …

What Lies Beneath? Molecular Evolution During The Radiation Of Caecilian Amphibians, María Torres-Sánchez, David J. Gower, David Alvarez-Ponce, Christopher J. Creevey, Mark Wilkinson, Diego San Mauro

Neuroscience Faculty Publications

Background: Evolution leaves an imprint in species through genetic change. At the molecular level, evolutionary changes can be explored by studying ratios of nucleotide substitutions. The interplay among molecular evolution, derived phenotypes, and ecological ranges can provide insights into adaptive radiations. Caecilians (order Gymnophiona), probably the least known of the major lineages of vertebrates, are limbless tropical amphibians, with adults of most species burrowing in soils (fossoriality). This enigmatic order of amphibians are very distinct phenotypically from other extant amphibians and likely from the ancestor of Lissamphibia, but little to nothing is known about the molecular changes underpinning their radiation. …

Effects Of Temperature On Microbial Parameters Associated With Decaying Plant Litter In A Stream Microcosm Experiment, Hunter David Pates

Electronic Theses and Dissertations

Increases in mean surface air temperature under climate-change predictions are expected to affect microbial activity, as well as carbon dynamics in aquatic ecosystems. I explored responses of litter-associated decomposers along temperature ranges typical of temperate streams in laboratory microcosms simulating stream conditions. The objectives of this study were to determine (1) whether the effects of temperature on stream leaf-associated microorganisms can be explained by the Metabolic Theory of Ecology (MTE); (2) if the effects of temperature are the same across temperatures commonly found in temperate streams; and (3) if there are differences in the magnitude of responses to temperature among …

Microplastics In The Digestive System Of The Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) In Winyah Bay, Sc, Elise Virginia Pullen

Electronic Theses and Dissertations

The digestive tracts and livers of adult male Atlantic sharpnose sharks (N=16), Rhizoprionodon terraenovae, from Winyah Bay, South Carolina were examined for ingested microplastics. R. terraenovae is a small, locally abundant, coastal mesopredatory elasmobranch belonging to the family Carcharhinidae. Microfibers comprised the largest categories of plastics (94% of the total), and were found in 100% of sharks examined. The number of micro- and other plastics ranged from 34 to 75 per individual and totaled 927. The majority of plastics (40%) were blue in coloration, and 55% were <1 mm in length. Microplastics were observed on both the interior and exterior of the organs examined, and three microfibers were embedded within the stomach lining, an observation not previously reported in marine vertebrates and one which represents a potential pathway for the translocation of ingested microplastics.

Mesopredator Distribution, Abundance And Potential Competition With The American Burying Beetle (Nicrophorus Americanus) At Fort Chaffee Joint Maneuver Training Center, Karisa Fenton

Theses and Dissertations from 2019

The American burying beetle (Nicrophorus americanus, hereafter ABB) was listed as an endangered species in 1989 and many hypotheses have been developed to explain their rangewide decline. I investigated the carcass competition hypothesis that implicates increased competition between vertebrate scavengers and ABBs for appropriate-sized carcasses as a cause for ABB decline. Predators of medium size that occupy an intermediate trophic level (hereafter mesopredators) are potential competitors for carcasses. I used camera trapping to assess mesopredator abundances in nine different habitats at Fort Chaffee Joint Maneuver Training Center (FCJMTC) in western Arkansas because this area supports the largest known population of …

Rationale, Design, And Baseline Characteristics Of Walkit Arizona: A Factorial Randomized Trial Testing Adaptive Goals And Financial Reinforcement To Increase Walking Across Higher And Lower Walkable Neighborhoods, Marc A. Adams, Jane Hurley, Christine Phillips, Michael Todd, Siddhartha Angadi, Vincent Berardi, Melbourne F. Hovell, Steven Hooker

Psychology Faculty Articles and Research

Little change over the decades has been seen in adults meeting moderate-to-vigorous physical activity (MVPA) guidelines. Numerous individual-level interventions to increase MVPA have been designed, mostly static interventions without consideration for neighborhood context. Recent technologies make adaptive interventions for MVPA feasible. Unlike static interventions, adaptive intervention components (e.g., goal setting) adjust frequently to an individual's performance. Such technologies also allow for more precise delivery of “smaller, sooner incentives” that may result in greater MVPA than “larger, later incentives”. Combined, these factors could enhance MVPA adoption. Additionally, a central tenet of ecological models is that MVPA is sensitive to neighborhood environment …

Mapping Wilderness Character In Adams County, Pennsylvania, Alyssa J. Kaewwilai

Gettysburg Social Sciences Review

The spatial trends in wilderness character in Adams County, Pennsylvania were examined to evaluate how influenced specific areas are impacted by human activity and development. Indicators of wilderness character were selected as natural, untrammelled, undeveloped, along with solitude and unconfined recreation by the Death Valley National Park staff in which a 0-4 ranking system was based upon to portray a range of most degraded to optimal land. This was executed through examination of factors such as abundance of biodiversity and human development within the given area before a Monte Carlo simulation was run to show sensitivity of change. It was …

Forest Structure Of Long-Term Conserved Areas Utilizing Different Strategies On A Continental, Glacial Moraine Formed Island, Christopher Coggin

Masters Theses, 2010-2019

Understanding patterns of forest succession can help advise management plans within New England nature preserves. This study took place on Block Island, 13 miles off the coast of Rhode Island. The island has greater than 200+ years of farming practices. After 1960, conservation groups began reforesting the island using different strategies, such as actively planting with native and exotic tree species, mowing, and preventing further development. In 2018, woody vegetation was inventoried along transects within four reforested sites. Sites were characterized as the following: actively planted with exotic and native tree species and mowed (AP-M), actively planted with exotic and …

Anti-Crispr Vs. Crispr: The Evolutionary Arms Race Between Microorganisms, Rachael M. St. Jacques

Masters Theses, 2010-2019

CRISPR arrays are a defense mechanism employed by bacteria against viral invaders. Cas proteins do the work in detecting, capturing, and integrating the viral DNA into the CRISPR array (Barrangou et al., 2007). Anti-CRISPR proteins are produced by phages, viruses that infect bacteria, to stop the bacterial host’s CRISPR-Cas complex from interrupting the phage life cycle (Bondy-Denomy, et al., 2015).

SEA-PHAGES is a course-based bacteriophage research network composed of 120 colleges and known at James Madison University as Viral Discovery. JMU uses the unsequenced Streptomyces griseus ATCC10137 as a host for bacteriophage discovery and propagation, and in this study we …

Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan

Masters Theses, 2010-2019

Anthropogenically driven factors, such as increasing temperature and sediment in valley streams, acidification of mountain streams, and the introduction of non-native trout, are restricting habitat suitable for healthy populations of eastern brook trout (Salvelinus fontinalis) throughout their native Appalachian range. Brook trout are important as predators of insects in mountain streams and as a favorite of anglers. It is crucial that remaining populations in sustainable habitats be identified and preserved. Waterfalls are geologic knickpoints preventing base-level lowering that create unique, stable landscapes above them, which may alleviate the temperature-productivity/acidity “habitat squeeze” for populations of brook trout and could …

Reproductive Character Displacement In Calopteryx Aequabilis And C. Maculata: Improving Species Recognition Through The Divergence Of Male Mating Preferences, Melissa Encinias

Masters Theses, 2010-2019

An ongoing evolutionary question is how co-occurring species maintain reproductive barriers when they are morphologically, behaviorally, and ecologically similar. Without geographic isolation, traits involved in species recognition may be under selection to enhance reproductive barriers. Exaggerated trait differences between species in sympatric populations may reflect selection to reduce misdirected mating between species, or reproductive character displacement. While this phenomenon is widely recognized as an important stage in the speciation process, there is little direct evidence of this process in nature. In two North American damselfly species, Calopteryx aequabilis and C. maculata, wing pigmentation is sexually dimorphic and also shows …

Urban Stream Restoration: An Evaluation Of Material Processing And Conveyance Channels, Madeline Berg

Masters Theses, 2010-2019

Stream restoration is gaining popularity in the Mid - Atlantic region to offset impacts from urbanization. Increased levels of impervious surfaces, decreased vegetation along banks, and changes in water flow patterns make urban stream ecosystems flashy and result in high erosion rates, increasing the amount of nutrients entering the Chesapeake Bay. Different restoration practices can play a large role in the amount of nutrients and organic matter leaving a stream and the amount of habitat that is present in-stream.

Due to the recent interest in stream restoration as a tool to help the health of the Chesapeake Bay, this study …

Examining The Effect Of Interstitial Space On Eastern Oysters (Crassostrea Virginica): Applications Of Photogrammetry And Three-Dimensional Modeling, Bailie Lavan

Masters Theses, 2010-2019

Global oyster populations have decreased by as much as 99% in the past century. Oysters are known ecosystem engineers, providing benthic habitat for macrofauna, linking benthic and pelagic food webs, improving water quality, and mitigating shoreline erosion. Restoration efforts are critical in re-establishing native oyster populations. In the Chesapeake Bay, where oyster loss is primarily due to severe over harvest, artificial substrates with geometric shapes are widely used in restoration efforts. However, natural oyster reefs form emergent shapes with a high degree of aggregation and many interstitial spaces (three-dimensional volumetric spaces between oysters within a reef). The lack of interstitial …

Herpetological Assemblages In Tropical Dry Forests Of The Azuero Peninsula, Panama: An Evaluation Of Reforestation, Tyler Kovacs

Masters Theses, 2010-2019

Tropical dry forests are considered one of the most endangered tropical ecosystems making reforestation increasingly necessary to restore Panama’s unique ecoregion. The isolated dry ecoregion surrounding the Bay of Parita in Panama has a long history of deforestation and cattle grazing. Successful reforestation of this land is important to restore ecosystem health and biodiversity. In Panama, reforestation ranges from monocultures of exotic teak (Tectona grandis) to passive regeneration. Faunal recovery within these reforestation systems may vary due to different habitat characteristics. In this study, amphibian and reptile communities were compared in two types of reforestation systems and protected riparian forests …

Contagious Yawning In The Domestic Cat (Felis Catus), Ariel M. Lombardo Aghishian

Theses and Dissertations

This study investigates contagious yawning in domestic cats towards their owners, looking at potential links with empathy. Results showed no significant difference in yawning between conditions. The solitary nature of wildcats and their shared ancestor, and the unique social behavior in domesticated cats may explain these findings.

Deicing Salts Influence Ranavirus Outbreaks In Wood Frog (Lithobates Sylvaticus) Tadpoles, Sarah Jacobson

Honors Scholar Theses

Ecosystems are increasingly being exposed to anthropogenic stressors that could make animals and thus populations more susceptible to disease. For example, the application of deicing salts to roads is increasing in the northeastern United States. Chronic stress that larval amphibians experience when living in vernal pools with high salinity may alter their susceptibility to ranavirus, a pathogen responsible for mass mortality events worldwide. This project quantifies the effects of road salts and ranavirus exposure on larval wood frog (Lithobates sylvaticus) growth and survival. Using outdoor mesocsoms, we raised wood frog tadpoles in salt treatments and then exposed them …

Nekton Usage Of High Marsh Habitats In Connecticut Salt Marshes, With Emphasis On The Genus Fundulus, Amanda L. Tucker

Master's Theses

Large scale habitat use patterns of salt marsh nekton are fairly well understood, but small-scale patterns within marsh habitats are not as well known, including the genus Fundulus, an important salt marsh species. This is an area of study that needs more research, particularly in light of increases in salt marshes loss within the last several decades. Salt marshes are a primary habitat for Fundulus species. Sea level rise and urbanization have been major contributors to salt marsh loss and alteration.

Salt marshes are highly variable habitats both spatially and temporally due to tidal cycles, high and low marsh areas …

The Role Of Oxytocin On Social Behavior Associated With The Formation Of A Social Pair-Bond In The Socially Monogamous Convict Cichlid (Amatitlania Nigrofasciata), Christopher Garcia

Graduate Theses

The mechanisms for monogamy have evolved several times throughout history across various taxa in accordance with selective pressures. In vertebrates, monogamy is facilitated by the formation and the maintenance of social pair-bonds between mates. Social pair-bonds are a form of selective attachment that require complex neurobiological pathways in order to develop and continue. These neurobiological pathways are often regulated by neuroendocrine mechanisms, such as the release of the two neuroendocrine nonapeptides, oxytocin and arginine vasopressin, in specific parts of the brain or body. These neuroendocrine peptides play a big role in social and sexual behaviors. In prairie voles (Microtus ochrogaster) …

A Test Of The Use Of Timber Wolf (Canis Lupus) Urine To Reduce Coyote (Canis Latrans) Depredation Rates On Loggerhead Sea Turtle (Caretta Caretta) Nests, Michael Wauson

Graduate Theses

Loggerhead sea turtles are currently listed as vulnerable by the International Union of Conservation of Nature (IUCN) with a decreasing population trend. Over the past four years, coyotes (Canis latrans) have depredated 24.18% of loggerhead sea turtle (Caretta caretta) nests on the night they were laid on South Island beach at the Tom Yawkey Wildlife Center, near Georgetown, SC. This has resulted in an estimated 4,002 eggs lost each year there. Over that time, a South Carolina Department of Natural Resources (SCDNR) Turtle Technician Team patrolled the beach at dawn every morning to cage and catalog loggerhead eggs and nests …

Correlation Between Sei Whale Distribution And Chlorophyll-A Concentration In The Western North Atlantic, Dawn Parry

Senior Honors Projects

The sei whale (Balaenoptera borealis) is an endangered baleen whale species whose distribution and migratory movements are poorly understood. Sei whale populations were decimated by commercial whaling in the 19th and 20th centuries. Much of what is currently known about their distributions comes from historical whaling records. Visual sightings, which may be sporadic and limited by weather and access to remote locations, are the primary source of data for recent research. It is thought that sei whale distributions may be influenced by the distribution of their food, which consists of zooplankton (small crustaceans, like shrimp), small fish, and …

Observations And Applications Of Husbandry Methodologies On A Backyard Poultry Farm In Dangriga, Belize, Bailey Carpenter

Animal Science Undergraduate Honors Theses

This study explores the husbandry methodologies on a backyard poultry farm in Dangriga, Belize, with the purpose of producing a set of guidelines for backyard poultry growers that have limited resources in similar regions. The majority of data collection occurred through survey questions approved by the IRB, necropsies approved by IACUC, and general observations. There has been a steady increase in poultry production in developing regions due to its positive effects on income and relative nutrition. However, due to a lack of accessible communication and education regarding effective and safe poultry production, these operators typically see poor productivity and/or profitability …

American White Pelicans, Tommy King

Wildlife Damage Management Technical Series

American white pelicans (Pelecanus erythrorhynchos, Figure 1) threaten aquaculture producers by direct predation and the spread of disease. They are also considered competition and a nuisance by some sports fishermen. Pelicans can also damage pond levees and crops, such as rice, by trampling the vegetation and depositing guano. A combination of wildlife damage management techniques is often necessary to reduce pelican damage to these resources. Aquaculture Prior to the winter of 1992, American white pelican depredations at catfish facilities in the Delta regions of Arkansas and Mississippi were limited, and birds were easily dispersed from the area. Since 1992, however, …

Intraspecific Variation In Plant-Plant Interactions And Belowground Zone Of Influence Of Big Sagebrush (Artemisia Tridentata), Andrii Zaiats

Boise State University Theses and Dissertations

Post-fire restoration of degraded sagebrush ecosystems over large areas of the Great Basin is challenging, in part due to unpredictable outcomes. Low rates of restoration success are attributed to increasing frequencies of wildfires, biological invasions, and climate variability. Quantifying restoration outcomes by accounting for sources of biotic and abiotic variability will improve restoration as a predictive science. One source of biotic variability is neighbor interactions, which can regulate demographic parameters of coexisting species and are an important determinant of community structure, ecosystem functions, and population dynamics. Our objective was to quantify how intraspecific variability in big sagebrush, Artemisia tridentata, …

Review Of Birds Of Prey Of The West: A Field Guide, By Brian K. Wheeler, Daniel Casey

The Prairie Naturalist

Birds of prey epitomize much of what attracts us to birding. Many are large and easy to observe, particularly in open landscapes. Their predatory nature and behavior give them an added aura of wildness; their migrations can be spectacular. And even veteran birders should enjoy the challenge of identifying the myriad of plumage variations shown by different ages, sexes, subspecies, and color morphs. With his newest effort, Birds of Prey of the West, Brian Wheeler has compiled a comprehensive and enhanced field guide with illustrations that stunningly capture that variation, combined with enough additional context to make it a valuable …

Beaver And Aspen: Synergy Among Keystone Species, Stephen N. Bennett, Nicolaas Bouwes, Paul C. Rogers

Aspen Bibliography

In the West, climate change is likely to increase the frequency, intensity, and duration of drought. Restoration of soils and water storage capacity can help create resilient uplands and riverscapes (i.e., streams and the valley bottoms). Over the past two centuries, common land uses, the removal of beaver and wood, straightening of streams, and damage to riparian areas have created simplified, structurally starved, riverscapes. Degraded streams are very efficient at transporting water, sediment, and nutrients downstream. Aspen forests are also biological hotspots that have been degraded by past land uses such as overbrowsing ungulates, land clearing, fire suppression, and outright …

Biodiversity Within Aspen Forests, Paul C. Rogers

Aspen Bibliography

Aspen have long been known for supporting lush vegetation and rich wildlife habitat. These features, alongside brilliant green and gold seasonal coloration, accompany a broadly appreciated aesthetic for aspen forests by the public-at-large. However, in earlier times timber producers in many locales considered aspen to have low value and actively eliminated them. More recent research has pointed out that relative moisture held within aspen communities facilitates a wide array of species – collectively, biodiversity – compared to surrounding vegetation types. Aspen groves in the Intermountain West, for example, are known to be second only to riparian forests is supporting the …

Role Of Wildfire And Topography In Shaping Aspen Regeneration After The Hayman Fire, Co, Usa, Arianna A. B. Porter

Aspen Bibliography

Unusually rapid and widespread mortality in Quaking aspen (Populus tremuloides) has been documented throughout the 21st century primarily as a result of warm, dry weather conditions. Although aspen are not drought-adapted, aspen are well adapted to wildfire. Increases in wildfire severity and extent as a result of climate change may provide opportunities for aspen regeneration, especially at mid- and high-elevation sites. Aspen's sensitivity to drought suggests that regeneration following fire might be constrained to cooler and wetter topographic locations on the landscape which reduce drought stress on vegetation. While aspen mortality is demonstrated to occur at low elevation sites, aspen …

Burn Severity And Fire History In The Northwestern Canadian Boreal Forest: Drivers And Ecological Outcomes, Ellen Whitman

Aspen Bibliography

Wildfire is the dominant stand-renewing disturbance in the northwestern Canadian boreal forest. Fires burn extensive areas in Canada, disturbing an average of 1.96 Mha yr−1, primarily in the boreal zone. Fires generally occur every ~30 – > 200 years in this region, due in part to a lack of fuel that allows young stands to resist reburning. Boreal understory plants and trees are adapted to stand-renewing wildfire through mechanisms such as serotiny, seed banking, and resprouting from roots and rhizomes of top-killed individuals. Such adaptations confer resilience to boreal forests, and post-fire vegetation communities generally resemble the pre-fire ones, following a …