Climate Interactions Drive Tree Physiology And Growth In A Northeastern Forest Ecotone, 2023 University of Maine
Climate Interactions Drive Tree Physiology And Growth In A Northeastern Forest Ecotone, Alexandra M. Barry
Electronic Theses and Dissertations
Climate change is a threat to global forest ecosystems. In the northeastern United States, forest trees are facing rising temperatures and increasingly inconsistent moisture regimes. In addition to long-term changes in climate conditions, there is concern about the potential for more frequent and intense climate extremes, which can have severe and rapid negative effects on tree physiology and growth. Further, climate extremes may co-occur to produce a greater magnitude of effect than the sum of their parts, with a prominent example being hot droughts, which are increasing in occurrence and severity. The impact of these and other extreme climate interactions …
Effects Of Large Wood Additions On Basal Resources, Macroinvertebrates, And Ecosystem Processes In The Narraguagus River, Maine, 2023 University of Maine
Effects Of Large Wood Additions On Basal Resources, Macroinvertebrates, And Ecosystem Processes In The Narraguagus River, Maine, Val Watson
Electronic Theses and Dissertations
Ecological restoration is an increasingly common practice across ecosystems, and current practices aim to restore the biological and physical processes underlying ecosystem function, often for the sake of endangered higher-level consumers. Studies of restoration outcomes often report few or inconsistent ecological changes, and monitoring of restoration projects rarely measures ecological processes. Monitoring also usually measures outcomes at a single scale, despite the prevalence of scale- dependent phenomena across ecosystems. My thesis uses measurements of ecological processes to assess restoration response and evaluates responses across multiple scales. I focus here on a long-term large wood addition project on the Narraguagus River …
Genetic Effects Of Anthropogenic Disturbance On Native Charrs, 2023 University of Maine
Genetic Effects Of Anthropogenic Disturbance On Native Charrs, Brad Erdman
Electronic Theses and Dissertations
Artificial propagation has been utilized for over a century to offset anthropogenic declines of abundance for many fishes. Complex and poorly documented histories of habitat degradation and stockings have resulted in considerable uncertainty regarding whether contemporary populations are of native, hatchery, or mixed origins. This uncertainty is problematic as it precludes prioritizing the conservation of native populations that are postulated to possess local adaptations and greater evolutionary potential. Population genetics can assess the relative reproductive contributions of previous stocking events and in this dissertation I apply these methods to four empirical studies of native charr (genus Salvelinus) that have …
The Devil You Know And The Devil You Don’T: Current Status And Challenges Of Bovine Tuberculosis Eradication In The United States, 2023 Michigan Department of Natural Resources
The Devil You Know And The Devil You Don’T: Current Status And Challenges Of Bovine Tuberculosis Eradication In The United States, Daniel J. O'Brien, Tyler C. Thacker, Liliana C.M. Salvador, Anthony G. Duffiney, Suelee Robbe‑Austerman, Mark S. Camacho, Jason E. Lombard, Mitchell V. Palmer
USDA Wildlife Services: Staff Publications
Having entered into its second century, the eradication program for bovine tuberculosis (bTB, caused by Mycobacterium bovis) in the United States of America occupies a position both enviable and daunting. Excepting four counties in Michigan comprising only 6109 km2 (0.06% of US land area) classified as Modified Accredited, as of April 2022 the entire country was considered Accredited Free of bTB by the US Department of Agriculture for cattle and bison. On the surface, the now well-described circumstances of endemic bTB in Michigan, where white-tailed deer (Odocoileus virginianus) serve as a free-ranging wildlife maintenance host, may appear to be …
Parasites Versus Predation: The Role Of Chronic And Acute Parasite Exposure In Infection Risk And Anti-Predator Behavior, 2023 Nova Southeastern University
Parasites Versus Predation: The Role Of Chronic And Acute Parasite Exposure In Infection Risk And Anti-Predator Behavior, Delaney Farrell
All HCAS Student Capstones, Theses, and Dissertations
Parasites with complex, multi-host lifecycles often engage in host behavior manipulation to increase transmission between successive hosts. In intermediate fish hosts, previous research has measured increased frequency of conspicuous behaviors, decreased swimming performance, and reduced antipredator behavior, which would collectively increase the fish’s risk of predation. In ecosystems where this type of parasite increased trophic transmission (PITT) occurs, parasites can play a substantial role in food webs. In this study, I investigate how chronic versus acute exposure to the trematode Euhaplorchis sp. A. affects the antipredator behavior of the Gulf killifish Fundulus grandis. Using a fully crossed design, I …
A Four-Pronged Approach To Addressing A Wild Pig Invasion In A Bottomland And Upland Forested Landscape, 2023 Mississippi State University
A Four-Pronged Approach To Addressing A Wild Pig Invasion In A Bottomland And Upland Forested Landscape, Tyler Scott Evans
Theses and Dissertations
Among exotic species that are capable of invading, establishing, and reaching pest status, few pose the range of impacts to biotic (e.g., competition with native species, predation, herbivory, introduction of other exotics) and abiotic (e.g., soil, hydrology) ecosystem components that can be attributed to the wild pig (Sus scrofa). Despite the presence of wild pigs throughout the southeastern United States for centuries, new invasions continue to occur in previously uninhabited and often under-investigated landscapes, including bottomland and upland forests. The recent invasion of the Sam D. Hamilton Noxubee National Wildlife Refuge (hereafter, NNWR) in east-central Mississippi represents an …
Timing Is Everything: Climate Change Implications For Phenological Events And Reproductive Success In River Herring, 2023 University of Massachusetts Amherst
Timing Is Everything: Climate Change Implications For Phenological Events And Reproductive Success In River Herring, Meghna N. Marjadi
Doctoral Dissertations
Anadromous river herring (alewife (Alosa pseudoharengus) and blueback herring (Alosa aestivalis)) make annual spring spawning migrations from the ocean to freshwater, where juveniles reside before emigrating to the ocean. Climate change may alter environmental and biological cues that prompt both adult migration and juvenile emigration, with implications for adult spawning success and offspring survival for these imperiled species. Shifts in adult migration have been observed in some rivers, while impacts on reproductive success and juvenile survival remain unknown. Cues for juvenile emigration are poorly understood as they have been explored at limited spatial and temporal scales. …
Discovery Of An Introduced Florida Flagfish (Jordanella Floridae) Population In Coastal Mississippi, 2023 Mississippi Museum of Natural Science
Discovery Of An Introduced Florida Flagfish (Jordanella Floridae) Population In Coastal Mississippi, Robert Ellwanger, Samuel E. Hunt, Calvin R. Rezac, Matthew D. Wagner
Southeastern Fishes Council Proceedings
The recent discovery of Jordanella floridae (Florida Flagfish) in Harrison County, Mississippi represents the first known occurrence of the species in the state. Native along the Atlantic and Gulf Coasts of Florida from Jacksonville to Tallahassee, this species has been introduced outside of its range via aquarium introductions. We hypothesize that an aquarium introduction was also the source of the newly discovered population, which has persisted at the location since 2020. Multiple collections of the species have been taken from a small waterbody which has a direct connection to the Tchoutacabouffa River (25mm-47mm TL). While it is unknown if this …
Leveraging Eco-Evolutionary Models For Gene Drive Risk Assessment, 2023 NWRC, Fort Collins, CO
Leveraging Eco-Evolutionary Models For Gene Drive Risk Assessment, Matthew A. Combs, Andrew J. Golnar, Justin M. Overcash, Alun L. Lloyd, Keith R. Hayes, David A. O'Brochta, Kim M. Pepin
USDA Wildlife Services: Staff Publications
Engineered gene drives create potential for both widespread benefits and irreversible harms to ecosystems. CRISPR-based systems of allelic conversion have rapidly accelerated gene drive research across diverse taxa, putting field trials and their necessary risk assessments on the horizon. Dynamic processbased models provide flexible quantitative platforms to predict gene drive outcomes in the context of system-specific ecological and evolutionary features. Here, we synthesize gene drive dynamic modeling studies to highlight research trends, knowledge gaps, and emergent principles, organized around their genetic, demographic, spatial, environmental, and implementation features. We identify the phenomena that most significantly influence model predictions, discuss limitations of …
Fishing Out Nutrients: The Spatiotemporal And Ecological Dynamics Of Fishery-Based Nutrient Extraction, 2023 Utah State University
Fishing Out Nutrients: The Spatiotemporal And Ecological Dynamics Of Fishery-Based Nutrient Extraction, Adrián A. González Ortiz
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Marine fisheries are one of the most impactful human activities on the planet. Since the 1950s, marine fisheries have removed billions of metric tons of marine biomass leading to substantial declines in many fish populations. Among their impacts, we have begun to investigate the role of fisheries in disrupting marine nutrient cycles. Specifically, removing biomass can change nutrient cycles by reducing the amount of nutrients stored within animal biomass.
No studies have investigated the large-scale geographical and ecological contexts of nutrient removal by fisheries over a large timescale. For my thesis, we compiled data on fishery-targeted organisms' carbon, nitrogen, and …
Overcoming Barriers To Aquatic Plant Restoration: Addressing Gaps In Species Identification And Planting Techniques In The Intermountain West, 2023 Utah State University
Overcoming Barriers To Aquatic Plant Restoration: Addressing Gaps In Species Identification And Planting Techniques In The Intermountain West, Kate A. Sinnott
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Aquatic ecosystems provide many critical and economically valuable benefits, including drinking water, food, recreational opportunities, and water supply for irrigation and agriculture. However, the health of these systems has been severely impacted by human activities such as pollution, land conversion, and introductions of harmful species. Restoring native aquatic plants can help reverse this damage and reestablish benefits, though it is not a common practice. With an objective to increase capacity for aquatic plant restoration in the Intermountain West, I identified and addressed two major barriers: 1) a lack of confidence in aquatic species identification among wetland professionals, and 2) underdeveloped …
Evidence Of Competitive Release Following Overstory Mortality In A Semi-Arid Piñon-Juniper Woodland, 2023 University of New Mexico
Evidence Of Competitive Release Following Overstory Mortality In A Semi-Arid Piñon-Juniper Woodland, Corrie D. Gonzalez
Biology ETDs
Extreme temperatures and severe drought events have led to widespread tree mortality worldwide. In semi-arid regions of the Southwest United States, these events pose a significant threat to piñon-juniper (PJ) woodlands. We studied the effects of piñon and juniper mortality on the growth and physiology of existing saplings in PJ woodlands by analyzing water status, photosynthetic activity, and tissue chemistry to gain insights into these impacts. Juniper saplings exhibited improved water status and water use efficiency in response to overstory mortality, whereas piñon saplings did not. Additionally, both piñon and juniper saplings exhibited increased photosynthetic rates, increased photosynthetic capacity, and …
Influence Of Abiotic Drivers And Plant Community Interactions On Bald Cypress (Taxodium Distichum) Seedlings: Implications For Restoration, 2023 Old Dominion University
Influence Of Abiotic Drivers And Plant Community Interactions On Bald Cypress (Taxodium Distichum) Seedlings: Implications For Restoration, Victoria Ellis
Biological Sciences Theses & Dissertations
Forested freshwater wetlands are valuable ecosystems that provide habitat for numerous species, sequester carbon, and act as sinks for excess water and nutrients. Historically, these ecosystems have been heavily degraded by anthropogenic activities leading to loss of ecosystem services and a desire to restore freshwater forested wetland habitat. Thus, science-backed approaches for the restoration of freshwater forested wetlands are necessary to ensure restoration goals are met. This body of research employed the Stress Gradient Hypothesis to test whether a multi-species planting approach using Juncus effusus (L.) (soft rush) could facilitate the survival of Taxodium distichum (L.) Rich. (bald cypress) seedlings …
Monitoring The Effects Of Poultry Waste On Fishes And Macroinvertebrates In The Sabine River, 2023 University of Texas at Tyler
Monitoring The Effects Of Poultry Waste On Fishes And Macroinvertebrates In The Sabine River, Karley R. Parker
Biology Theses
Freshwater is a vital resource that provides life and sustainability for almost all organisms on Earth. It is important to maintain its health and protect it from emerging pollutants that pose a threat to the organisms that use it. Pollution continues to threaten the well-being of the environment’s freshwater sources all around the world that could lead to damaging effects in the future. The Sabine River is a major freshwater resource in the east Texas and western Louisiana areas that provides a habitat for thousands of organisms as well as other domestic uses for humans. In 2019, a waste discharge …
An Ecological Survey Of East Texas Salamanders Across The Camp Tyler Outdoor Field School In Smith County, Texas, 2023 The University of Texas at Tyler
An Ecological Survey Of East Texas Salamanders Across The Camp Tyler Outdoor Field School In Smith County, Texas, Justin C. Hunt
Biology Theses
Amphibians are a unique class of organisms with a very long and storied evolutionary history of survival. Many modern amphibian clades occupy several vital ecological roles within their native freshwater environments. One of these roles, typically includes functioning as an ecological indicator species, whereby the presence of stable and diverse populations of many amphibian species, including salamanders, within a freshwater ecosystem have long been considered ecological indicators of good habitat quality and stable ecosystem health. Similarly, salamanders also function as important members of their local food webs and act as valuable mediators of complex trophic hierarchies to facilitate nutrient cycling …
Commercial Fishing Identification Guide 2023, 2023 Department of Primary Industries and Regional Development, Western Australia
Commercial Fishing Identification Guide 2023, Department Of Primary Industries And Regional Development, Western Australia
Fisheries occasional publications
Throughout this guide you will see all or some of the marine bioregion symbols with each fish illustration, indicating where the species is most likely to occur.
This guide has been developed to help you identify the more common species in Western Australia you may encounter. The purpose of this guide is to enhance consistent and accurate species identification.
If you are unsure about a particular species (or if it is not in this guide), please discuss it with a representative of the Department of Primary Industries and Regional Development, Western Australia.
Pronghorn Survival And Resource Selection In Western Nebraska's Agriculturally Dominated Landscape, 2023 University of Nebraska-Lincoln
Pronghorn Survival And Resource Selection In Western Nebraska's Agriculturally Dominated Landscape, Katie Piecora
School of Natural Resources: Dissertations, Theses, and Student Research
Nebraska’s pronghorn population has been stable over the last decade, yet their presence on the landscape remains a contentious subject amongst private landowners. Conversion of grassland for crop production and increased anthropogenic activity has drastically altered pronghorn behavior throughout their current range, however basic ecology and resource use by pronghorn in Nebraska remains poorly understood. Establishing baseline population metrics and seasonal patterns of resource use for this population at the eastern periphery of the species range is critical to guide management actions. We deployed GPS collars on 110 adult pronghorn to quantify survival, mortality risk, and seasonal resource selection in …
The Impact Of Road Crossings On Karst Headwater Streams In Northwest Arkansas, 2023 Arkansas Tech University
The Impact Of Road Crossings On Karst Headwater Streams In Northwest Arkansas, Anthony M. Zenga
ATU Theses and Dissertations 2021 - Present
The karst region of NW Arkansas is home to many headwater endemic Species of Greatest Conservation Need (SGCN). This includes many species of darters, such as Etheostoma cragini, E. microperca, and E. mihileze, as well as crayfish such as Faxonious meeki brevis and F. nana. NW Arkansas is rapidly urbanizing, increasing the need to construct structures like culverts, bridges, and fords. These man-made road crossings can cause stream habitat degradation and fragmentation, as well as impair overall stream connectivity. To evaluate the impact that road crossings have on aquatic SGCN species and their habitat, 30 headwater streams were sampled throughout …
Skeletal Anatomy Of The Pectoral Fin In Mudskipper Species From Terrestrial And Aquatic Habitats, 2023 University of Ottawa
Skeletal Anatomy Of The Pectoral Fin In Mudskipper Species From Terrestrial And Aquatic Habitats, Haodong Zhou, Cassandra M. Donatelli, Odette Laneuville, Emily M. Standen
Engineering Faculty Articles and Research
Mudskippers are a group of amphibious fishes in the family Oxudercidae, whose species inhabit a range of habitats from mostly aquatic to mostly terrestrial. Most of our understanding about habitat preference comes from natural history observations, particularly where they are collected (i.e., low intertidal vs. high intertidal regions). Mudskippers have undergone several morphological changes to accommodate a terrestrial life, including major changes to the pectoral and pelvic girdles. These changes result in a novel crutching gait, which mudskippers use to move over land. Though the appendicular morphology and crutching gait of mudskippers have been described in some species, few …
Incorporating Metapopulation Dynamics To Inform Invasive Species Management: Evaluating Bighead And Silver Carp Control Strategies In The Illinois River, 2023 U.S. Fish and Wildlife
Incorporating Metapopulation Dynamics To Inform Invasive Species Management: Evaluating Bighead And Silver Carp Control Strategies In The Illinois River, Jahn Kallis, Richard Erickson, D. P. Coulter, Alison A. Coulter, Marybeth K. Brey, Matt Catalano, John Dettmers, James Garvey, Kevin Irons, Elizabeth Marschall, Kenneth Rose, Mark Wildhaber, David Glover
Natural Resource Management Faculty Publications
1. Invasive species management can benefit from predictive models that incorporate spatially explicit demographics and dispersal to guide resource allocation decisions.
2. We used invasive bigheaded carps (Hypophthalmichthys spp.) in the Illinois River, USA as a case study to create a spatially explicit model to evaluate the allocation of future management efforts. Specifically, we compared additional harvest (e.g. near the invasion front vs. source populations) and enhanced movement deterrents to meet the management goal of reducing abundance at the invasion front.
3. We found additional harvest in lower river pools (i.e. targeting source populations) more effectively limited population sizes upriver …