Terrestrial and Aquatic Ecology Commons^™

Influence Of Invasive Species, Drought, And Stream Permanence On Stream Crayfish Species With A Focus On The Imperiled Mammoth Spring Crayfish (Faxonius Marchandi), Leah Marie Bayer

Graduate Theses and Dissertations

Freshwater crayfish constitute one of the most-threatened taxonomic groups in North America. Invasion by other crayfish species as well as habitat degradation through alteration of natural flow regime are two of the most prominent threats to crayfish persistence. Additionally, extreme weather events like droughts can amplify threats posed by other stressors on crayfish populations and are expected to increase in frequency, magnitude, and/or duration in the future, which may negatively influence narrow-ranged endemic crayfish populations typical of the Southeast. The Mammoth Spring Crayfish, Faxonius marchandi, is a narrow-ranged endemic that occurs in the Spring River drainage of Arkansas and Missouri …

Effects Of Climate Change On (Semi)-Arid Ecosystems In The Southwestern United States, Charlotte Van Der Nagel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Climate change is considered amongst the most severe threats to terrestrial and aquatic ecosystems globally. Ecosystems in the southwestern United States have specifically been impacted by intense drought conditions since 2000. Higher temperatures combined with altered precipitation stresses many ecosystems; however, ecosystem specific responses to such stressors may vary. Here, the effects of climate change on semi-arid ecosystems are analyzed for some of the most vulnerable ecosystems in the southwestern United States: lacustrine, riparian, and dryland ecosystems.

Lakes and reservoirs in arid environments often serve as drinking water sources and recreational areas where high water quality is essential. Climate change …

Uvc And Planetary Habitability: Insights From Desert Lichens And Cyanobacteria, Tejinder Singh

UNLV Theses, Dissertations, Professional Papers, and Capstones

An important question in astrobiology is whether life can exist under the levels of UVC radiation found on Archean Earth, Mars, and exoplanets. We investigated this question by studying the UVC survival of colonial cyanobacterium and lichens that grow in harsh desert environments and possess natural sunscreens. We irradiated them nonstop in a desiccated state with a UVC flux closely representing the upper limit on those planets: 55-60 W/m². After irradiation, we rehydrated and assessed their survival using chlorophyll fluorometry and by counting the number of viable colonies that formed on agar plates. All three study organisms survived two to …

Seed Dispersal By Martu Peoples Promotes The Distribution Of Native Plants In Arid Australia, Rebecca Bliege Bird, Douglas Bird, Christopher T. Martine, Chloe Mcguire, Leanne Greenwood, Desmond Taylor, Tanisha M. Williams, Peter M. Veth

Faculty Journal Articles

Commensal relationships between wild plants and their dispersers play a key ecological and evolutionary role in community structure and function. While non-human dispersers are often considered critical to plant recruitment, human dispersers have received much less attention, especially when it comes to non-domesticated plants. Australia, as a continent historically characterized by economies reliant on non-domesticated plants, is thus a key system for exploring the ecological role of people as seed dispersers in the absence of agriculture. Here, we utilize a controlled observation research design, employing ecological surveys and ethnographic observations to examine how seed dispersal and landscape burning by Martu …

Elevational Gradients Shape Bee Network Structure And Community Composition Across Tropical Lowland To Montane Forests In Costa Rica, Jenny Hsu

Online Theses and Dissertations

Mutualistic networks, such as those between plants and pollinators, play a crucial role in ecosystem stability and resilience. Previous theoretical work has posited that mutualistic networks with higher diversity, connectance, nestedness, interaction diversity and more generalist species are more resilient and stable. However, in some ecosystems, specialized interactions and specialists may promote network stability. Drivers of network properties in the neotropics, especially low and mid-elevations, remain relatively unknown, and thus this area should receive special attention. Replicated empirical networks comparing properties along environmental gradients in these regions can help contribute to resolving this debate. A total of 28 networks, replicated …

Impact Of Containment And Elevation On Created Marsh Plant Community And Ecosystem Dynamics, Kevin R. Stoner

LSU Master's Theses

Coastal marsh restoration is increasing globally, as marshes are impacted by anthropogenic impacts. Billions of dollars are allocated to marsh restoration in the Mississippi River delta where wetland loss rates are extremely high. The recovery of structural and functional attributes of created marshes varies by attribute measured and project. Here, two marshes created in 2018 and one natural marsh were used to examine how variations in hydrologic connectivity and marsh elevation influence subsurface hydrology and salinity, vegetation community structure, soil properties, accretion, and denitrification. I established a comparative field study in a created marsh contained within a higher elevation containment …

Microplastic Accumulation In The Marsh Periwinkle (Littoraria Irrorata), Sarah Keaton, Hannah Lukhard, Eli Windy, Manar Hasan

DePaul Discoveries

Contamination of oceans by microplastics (mm) currently poses a major threat to aquatic and terrestrial ecosystems worldwide. Recent attention towards this issue has raised questions about the extent to which microplastics have accumulated in the environment, and has led to an increase in studies on the effects of microplastics in various organisms. However, levels of contamination in protected natural areas are still largely unexplored, yet can offer an important empirical perspective on the issue. In addition, little is known about the potential effects of microplastics on behavior in the field. This research was conducted within the protected ACE Basin National …

Spatial Ecology Of Mountain Lions Throughout Their Distribution In California, Kyle D. Dougherty

School of Natural Resources: Dissertations, Theses, and Student Research

Mountain lions (Puma concolor) have been studied extensively throughout their wide geographic distribution in the Western Hemisphere, but most research has been conducted at relatively small spatial scales. We used GPS telemetry data contributed by researchers in 16 study areas throughout California to advance understanding of mountain lion spatial ecology. First, we investigated multi-scale resource selection of mountain lions relative to spatially varying risk of intentional human-caused mortality associated with livestock depredation management. We show that individuals that proactively avoided mortality risk when selecting home ranges were able to relax their avoidance of risk when making resource selection …

Spatial Ecology Of Mountain Lions Throughout Their Distribution In California, Kyle Duncan Dougherty

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Mountain lions (Puma concolor) have been studied extensively throughout their wide geographic distribution in the Western Hemisphere, but most research has been conducted at relatively small spatial scales. We used GPS telemetry data contributed by researchers in 16 study areas throughout California to advance understanding of mountain lion spatial ecology. First, we investigated multi-scale resource selection of mountain lions relative to spatially varying risk of intentional human-caused mortality associated with livestock depredation management. We show that individuals that proactively avoided mortality risk when selecting home ranges were able to relax their avoidance of risk when making resource selection …

Spatial And Abiotic Effects Of Urbanization On Small Mammal Communities, Bri Casement

Master's Theses

Urbanization, the phenomenon of increasing human population density and artificial structures, is known to decrease the richness, abundance, and diversity of native wildlife populations, fragment natural areas, and increase human and human-commensal animal interactions with wildlife. Dynamics of species persistence in habitat fragments is often understood in the framework of island biogeography theory (IBT), with habitat fragments being analogous to oceanic islands. Despite the conceptual similarities between oceanic islands in IBT and urbanized habitat fragments (fragment size, fragment age, and distance to immigration sources), there are important differences. In urban fragments, the matrix is not completely impassible, habitats within fragments …

The Relationship Between Changing Land Cover And Benthic Macroinvertebrate Diversity In Choccolocco Creek, Northeast Alabama, Kindall Brown

Theses

Land cover changes, driven by urbanization, agriculture, and deforestation, significantly affect the physical and chemical characteristics of water bodies at both the watershed and riparian levels. At the larger spatial scale, a stream’s surrounding watershed facilitates lateral inputs into the stream that are essential for biodiversity support, hydrological stability, and water quality. When a stream becomes disconnected from the lateral inputs due to urban or agricultural development, the morphology of the stream is significantly altered. On a smaller spatial scale, the riparian zone can act as a buffer to pollutants. The vegetation surrounding the stream bank promotes stability to the …

Scientific Note: An Incursion Of The Widely-Cultivated Katsura (Cercidiphyllum Japonicum, Cercidiphyllaceae) In Pennsylvania, Kayleigh R. Long, Melody P. Sain, Elizabeth H. Williams, Christopher T. Martine

Faculty Journal Articles

Cercidiphyllum japonicum (katsura) is a dioecious tree native to China and Japan. Although imperiled in parts of its natural distribution, the species has become quite common as a cultivated tree in temperate North America. The species is noted as occasionally escaping cultivation in the eastern United States, but few records of established incursions (and the conditions under which they might recruit) exist in the literature. We here report an incursion of C. japonicum in central Pennsylvania, along with notes on seedling recruitment on the Bucknell University campus.

New Insights On Hybridization In Potamogeton Floridanus (The Florida Pondweed), Kaitlyn R. Sampson

Graduate Theses and Dissertations (2019 - present)

Freshwater ecosystems are some of the most important and highest threatened habitats in the world, and aquatic plants play an important, but often-overlooked, role in maintaining them. Potamogeton is a diverse and ecologically important aquatic plant genus well known for taxonomic difficulty and rampant hybridization. lbis study aimed to 1) test the hypothesis that Potamogeton jloridanus (Florida pondweed) is a hybrid between P. oakesianus and P. pulcher, and 2) to investigate correlations in ecological conditions for the focal species. This study revealed the discovery of a new population of P. jloridanus in Big Coldwater Creek in Santa Rosa Co., FL, …

Behavioural Distributions Of Macrophytes In An Oxbow Lake, Dhir Beel With Reference To Its Water Quality In Assam, India, Arup Nama Das, D. K. Sharma

Journal of Bioresource Management

An Oxbow lake, Dhir Beel, situated in Western Assam, India, stands as a habitat for a plethora of plant and animal species, nurturing a vibrant ecosystem within its freshwater environs. This study sought to address concerns surrounding pollution, encroachment, siltation, and overfishing within Dhir Beel. Over a span of three years (2016-2019), samples were meticulously collected from five distinct sites to analyze both water quality and macrophyte populations. Employing the APHA method, the physico-chemical parameters of the water were evaluated, while a comprehensive identification process was undertaken to categorize the macrophytes. These aquatic plants, spanning dicots, monocots, and pteridophytes, were …

A Library Of 39 Plant Peroxidases: Plants From The Families Cucurbitaceae And Brassicaceae Show Promising Peroxidase And Peroxygenase Activity, Sally Hess

Senior Honors Theses

Peroxidases are enzymes that reduce reactive oxygen species (ROS) and oxidize organic substances in living cells. The textile industry, wastewater treatment plants, immunological laboratories, and diagnostic laboratories have extensively used horseradish peroxidase for their oxidating needs. This research aims to provide a tool for identifying potentially useful sources of peroxidases in addition to specifically pinpointing a novel peroxygenase in jalapeño seeds. By using two widely accepted peroxidase assays, the guaiacol assay and the fluorophenol assay, fruits of the genus Cucurbita and roots or leaves of the family Brassicaceae were seen to have high peroxidase activity. Additionally, novel peroxygenase activity was …

Fisheries Occasional Publication No.147 - Aquaculture Development Zones – Policy Position Relating To Permitted Alternative Species, Department Of Primary Industries And Regional Development, Western Australia

Fisheries Occasional Publications

The purpose of this policy is to set out considerations relevant to the assessment of aquaculture proposals within Aquaculture Development Zones (ADZ) for species distinct from the group of species for which the ADZ was initially established (Alternative Species).

Listening For Lemurs: Translating Black-And-White Ruffed Lemur (Varecia Variegata) Vocalizations Into Conservation Insights Through Acoustic Monitoring, Carly H. Batist

Dissertations, Theses, and Capstone Projects

The field of bioacoustic monitoring has undergone a significant evolution in recent years, driven by technological innovations that have revolutionized how researchers study animal vocalizations. Traditionally, bioacoustics was rooted in active acoustic monitoring (AAM), involving human observers using recorders in the field to study animal sounds and understand species' vocal communication. However, the emergence of passive acoustic monitoring (PAM) has introduced a new complementary approach, utilizing specialized recorders placed in ecosystems to autonomously capture sounds at wide spatial and temporal scales. My dissertation adopts a translational approach to bioacoustic monitoring, integrating both AAM and PAM techniques to study and survey …

Estimating Increased Transient Water Storage With Increases In Beaver Dam Activity, Konrad Hafen, Joseph M. Wheaton, Brett B. Roper, Philip Bailey, William W. Macfarlane, Bethany T. Neilson, Christopher J. Tennant

Watershed Sciences Faculty Publications

Dam building by beaver (Castor spp.) slows water movement through montane valleys, increasing transient water storage and the diversity of residence times. In some cases, water storage created by beaver dam construction is correlated to changes in streamflow magnitude and timing. However, the total amount of additional surface and groundwater storage that beaver dams may create (and, thus, their maximum potential impact on streamflow) has not been contextualized in the water balance of larger river basins. We estimate the potential transient water storage increases that could be created at 5, 25, 50, and 100% of maximum modeled beaver dam capacity …

From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel

Master's Projects and Capstones

Invasive plants cause significant impacts to ecosystems, the economy, and human health. California has experienced significant plant invasions and is well suited to future invasion because of its Mediterranean climate and human disturbance. Eradication or control of invasive plant species requires a detailed understanding of their spatial distribution, which typically involves on the ground surveys that can be expensive or inconsistent. Remote sensing offers a potential alternative or supplement to in-person invasive plant mapping. This study performed a comparative analysis of 41 remote sensing studies that mapped the distribution of California invasive plants. I found that while high spectral resolution …

Sub-Stage Climatic Shifts During Mis 11 Refined From Diatom Assemblage Reconstruction In The Valles Caldera, New Mexico, Savannah Cutler

Earth and Planetary Sciences ETDs

Diatom assemblage reconstruction from the Valles Caldera sediment core (VC-3) was utilized to infer climatic and aquatic changes during a 50-thousand-year [ka] period in the Mid-Pleistocene (435-385 ka). This 50 ka interval spans most of Marine Isotope Stage 11 (MIS 11) – one of the most prominent interglacials of the past 500 ka – and is widely considered an analog for the Holocene and future climate regimes. Nearly all records from MIS 11 are either marine or ice-core based, making VC-3 unique among lacustrine sediment records as it captures insolation variations and climatic changes during the mid-Pleistocene. Analysis of the …

Spawning Ecology And Spawning Site Fidelity Of Alligator Gar, Atractosteus Spatula, In The Fourche Lafave River: Implications For River-Floodplain Management And Alligator Gar Conservation, S. Reid Adams, Thomas E. Inebnit, Lindsey C. Lewis, Christopher J. Naus, Edward Kluender, Geoffry G. Spooner

Southeastern Fishes Council Proceedings

We studied the spawning ecology of Alligator Gar, Atractosteus spatula, in the Fourche LaFave River (FLR) of Arkansas to better understand their reproductive ecology and spawning resource requirements. Evidence of spawning was only observed in floodplain tributary habitats, particularly the small, adventitious headwater stream West Fork Mill Creek (WFMC). A mid-May to mid-June spawning season was observed for Alligator Gar in the FLR that corresponded with rising water levels (mostly due to backflooding from the Arkansas River) and increased water temperatures (> 20°C). Direct spawning observations at WFMC were made on 17 June 2007, 15 June 2008, 23 May …

Surface Water Quality Assessment Of Mingo Creek County Park: The Impacts Of Extractive Industries, Mikayla J. Bayto

Electronic Theses and Dissertations

Historical and current extraction operations and infrastructure, including natural gas pipelines, conventional and unconventional oil and natural gas drilling, longwall coal mining, and strip coal mining, occur throughout the Mingo Creek watershed of Washington County, Pennsylvania, including Mingo Creek County Park. Mingo Creek and several associated tributaries flow through Mingo Creek County Park, eventually discharging into the Monongahela River. An independent water quality study was conducted from June 2020 through July 2023 in Mingo Creek County Park to determine if historical and current extraction activities impact Mingo Creek and its associated tributaries. Weekly sampling of Mingo Creek and associated tributaries …

Phytoplankton Community Dynamics In The Northern California Current System, Kristin Forgrave

Student Research Symposium

The Northern California Current system is a productive coastal ecosystem that encompasses a variety of temporal and spatial features. The photosynthetic microbial community plays a crucial role in supporting the rich ecosystem and economically important fisheries. My research integrates data across distance and two years to investigate the community composition of two major phytoplankton groups in this system: picocyanobacteria and picoeukaryotes. The abundances and sizes of the phytoplankton were measured using flow cytometry. Picoeukaryotes were found to be present at similar concentrations in both summer and winter. Abundances of both cell types were comparable in the winter, but picocyanobacteria were …

Lmpact Of Salmonella Enterica Effector Proteins On Plant Physiology And Immunity, Sara Qader

Honors Theses

Salmonella enterica serovar Typhimurium are primarily recognized as pathogens associated with foodborne illnesses in humans. Salmonella also can colonize plant tissue effectively. The pathogen relies on type III secretion systems (T3SS) to infect mammals and plants successfully and counteract the immune response. Understanding the molecular mechanisms underlying Salmonella’s interactions with plants is essential for developing effective strategies to reduce its impact on human health and agriculture. Effector proteins, known for their role in modulating host-pathogen interactions, have been implicated in the virulence and pathogenicity of Salmonella. However, their specific functions and contributions to Salmonella’s interactions with plants remain largely unknown. …

Impacts Of Urbanization On Demographics And The Stress Level Of White-Tailed Deer In The Piedmont Of South Carolina, Cameron Bramhall

Graduate Theses

Population demographics and density studies are a common way of determining number of individuals in location. Understanding how many individuals and sex ratios can help estimate total populations for future potential management practices. For white-tailed deer (Odocoileus virginianus), commonly referred to as whitetail deer, like other cervids, having too many or too few individuals in an area can cause issues. Some of the issues that may arise with too many individuals include higher disease potential, and a general lack of resources leading to an increase in competition. As areas that were once habitat for whitetail deer become more and more …

Examining Context Dependency Of Invasion Hypotheses At The Continental Scale Using Riverine Fish Communities, Lily Thompson

All Dissertations

Many well-supported hypotheses seek to explain invasion dynamics, but evidence for common patterns among regions and taxa remains inconclusive and often contradictory. Invasion ecology is fundamentally linked to spatial scale, and discrepancies in results among invasion studies may be attributed, in part, to a failure to fully consider scale dependency. In this dissertation, I investigate the sources of inconsistencies across spatial scales and large geographic extents using riverine fish communities across the conterminous United States. To do so, I tested three main ideas. First, that cross-scale interactions contextualize estimated invasion mechanisms among regions. My results demonstrate that local empirical support …

The Spatial And Behavioral Ecology Of The Eastern Box Turtle In A Suburban Landscape, Emma Rogers

All Theses

Urbanization poses a significant threat to wildlife through fragmentation, degradation, and loss of habitats. Species response to urban development is variable, from species that thrive in urban areas to those that avoid them. Eastern box turtles (Terrapene carolina carolina) can live and reproduce in urban areas; however, reports of population decline throughout the species’ range have raised concerns. The objective of this study was to compare home range size and composition, as well as the microhabitat selection of the Eastern box turtle across a developmental gradient in Clemson, SC. We tracked 14 individuals in habitats along a developmental …

Consequences Of The Megafauna Extinction: Changes In Food Web Networks On The Edwards Plateau Across The Pleistocene-Holocene Transition, Quentin A. Smith Jr.

School of Biological Sciences: Dissertations, Theses, and Student Research

We are experiencing biodiversity loss due to climate change and human impacts, which is not only harmful to the environment but can also alter the composition of communities and interactions among species. The late Pleistocene experienced a loss of large-bodied mammals which resulted in significant changes in community structure due to changes in body size, diet, and species associations. The impact of these changes on species interactions and community structure across the Pleistocene-Holocene transition remains poorly understood. Using a robust data set of species composition, stable isotopes, body size, and climate variables, we constructed and compared ecological networks of mammal …

Ecological Dynamics Of Cenozoic North American Mammals, Alexandria Brandis Shupinski

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Understanding how community structure is affected by various ecological, climatic, and environmental changes is a long-standing goal in ecology. However, disentangling human impacts from these other variables is difficult when using short modern timescales and anthropogenically altered communities. The fossil record provides a means to investigate community structure dynamics across critical intervals, excluding humans as a variable. Here, in three studies, I assess changes in North American mammal paleocommunity structure across the last 66 million years (Ma) at multiple temporal and spatial scales. In Chapter 1, I identify changes in mammal functional diversity (FD) locally and continentally, using three independent …

Vibratory Noise Impacts The Sensory Ecology Of A Funnel-Weaving Spider, Brandi June Pessman

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Animals experience their world through diverse sensory systems, leveraging information from prey, predators, and potential mates to inform behavioral decisions. Environmental noise disrupts information via spectral or amplitude masking, degradation, or distortion, potentially leading to costly errors in responses. Critically, urbanization has accelerated the proliferation of novel noise sources, triggering significant shifts in communication, foraging, and predator-prey dynamics among urban wildlife. While vertebrate studies have illuminated urban animals’ flexibility to anthropogenic acoustic noise, a comprehensive understanding requires broader investigations across diverse animal taxa and sensory modalities. To address these gaps, my dissertation explored the impacts of anthropogenic substrate-borne (vibratory) noise …