Open Access. Powered by Scholars. Published by Universities.®

Terrestrial and Aquatic Ecology Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 271 - 300 of 6322

Full-Text Articles in Terrestrial and Aquatic Ecology

Ms Environmental Biology Capstone: Evaluating Environmental Risks And Conflicts In Golf Course Landscapes, Meredith Boos Jan 2025

Ms Environmental Biology Capstone: Evaluating Environmental Risks And Conflicts In Golf Course Landscapes, Meredith Boos

Regis University Student Publications (comprehensive collection)

1) This review investigates the relationship between pesticide use on golf courses and in agriculture to determine whether the adverse health effects documented in agricultural settings also apply to golf course environments. While the negative health effects from agricultural pesticide use are well established, golf courses use pesticides with greater frequency and intensity, suggesting a potentially higher exposure risk for both workers and players.

2) This study proposes methods to quantify pesticide bioaccumulation on golf courses and adjacent lands. We hypothesize that areas surrounding golf courses will exhibit a spatial gradient of pesticide accumulation, increasing with proximity to treated sites …


Acoustic Monitoring Of Oak Toads (Anaxyrus Quercicus), A Longleaf Pine (Pinus Palustris) Ecosystem Endemic Amphibian, Alex Ward Foote Jan 2025

Acoustic Monitoring Of Oak Toads (Anaxyrus Quercicus), A Longleaf Pine (Pinus Palustris) Ecosystem Endemic Amphibian, Alex Ward Foote

Theses, Dissertations and Capstones

The Longleaf pine ecosystem is one of the most endangered ecosystems in the world with only 3% remaining. Many endemic species to the longleaf pine ecosystem are also in decline and suffer from habitat loss resulting from fire exclusion, urbanization, agriculture, and industrial silviculture. Oak Toads (Anaxyrus quercicus) are a longleaf pine ecosystem obligate; the species is experiencing declines across its range and only has protections in Virginia and North Carolina. We used data from an array of Automated Recoding Units across four years (2013, 2014, 2015, 2019) at three state-owned wildlife management areas to capture audio files …


A Metadata Analysis Of Unionid Mussels Of The Greenup Pool Of The Ohio River Using Occupancy Modeling And Species Area Curves, Tyler Mitchell Annarino Jan 2025

A Metadata Analysis Of Unionid Mussels Of The Greenup Pool Of The Ohio River Using Occupancy Modeling And Species Area Curves, Tyler Mitchell Annarino

Theses, Dissertations and Capstones

Although North America contains the largest diversity of freshwater mussels in the world, only ~24% of species in the United States and Canada have stable populations. This group provides unique hurdles for surveying, and current unionid survey protocols include neither longitudinal studies nor randomization of sites. This project conducts a metadata analysis of freshwater mussels in the Greenup Pool of the Ohio River (GPOR) to answer three questions: 1. Does a combination of longitudinal scope, randomization of sites, and historic methodology of surveying result in useful occupancy/detection models (ODMs) of unionids in large streams at the family level? 2. Does …


Restored Wetlands Show Rapid Vegetation Recovery And Substantial Surface-Water Expansion, Thilina D. Surasinghe, Yin-Hsuen Chen, Kunwar K. Singh Jan 2025

Restored Wetlands Show Rapid Vegetation Recovery And Substantial Surface-Water Expansion, Thilina D. Surasinghe, Yin-Hsuen Chen, Kunwar K. Singh

Center for Geospatial Science, Education & Analytics Faculty Publications

Ecological restoration is essential for improving the ecological integrity of degraded ecosystems to enhance ecosystem services and biodiversity. In this study, we assessed the effectiveness of wetland restoration on retired cranberry farms by analyzing vegetation recovery and surface-water dynamics using the enhanced vegetation index (EVI) and normalized difference water index (NDWI) derived from Sentinel-2 satellite imagery. To quantify temporal dynamics of both vegetation recovery and surface-water cover, we identified the spectral distinctions among restored wetland plant communities. Our results indicated the emergence of distinct plant communities upon restoration. Restored wetlands in general showed significant and progressive vegetation recovery and expanding …


Effects Of In-Stream Large Woody Debris Management On Riparian Salamander Population Dynamics, Sydney Hermann Jan 2025

Effects Of In-Stream Large Woody Debris Management On Riparian Salamander Population Dynamics, Sydney Hermann

Theses, Dissertations and Capstones

The addition of large woody debris (LWD) into streams is an increasingly common habitat restoration method used to support brook trout populations and other sensitive freshwater species. Wood jams create localized reductions of water velocity, increase organic matter retention, intensify overbank flows, and promote habitat heterogeneity. These changes enhance interaction between the floodplain and the stream which can influence forest habitat variables such as leaf litter, soil pH, moisture, and invertebrate abundance. Salamander demographics reflect the stability of these forest habitat variables, and population declines can be indicative of environmental disturbance, stress, or change. Evaluating how this trout-targeted management effects …


Evaluating The Condition Of Age-0 Burbot In Relation To Diet, Cian Verbridge Jan 2025

Evaluating The Condition Of Age-0 Burbot In Relation To Diet, Cian Verbridge

Journal of Earth and Life Science

Burbot are becoming more and more popular for angling and aquaculture. However, populations have been declining across the world. Very little information is available about their early life and their interactions in the ecosystem due to challenges in sampling. Condition estimates and diet metrics were used to better understand the status of burbot in Lake Bemidji. Using backpack electrofishing, 45 young of the year burbot were collected. The lengths ranged from 86 to 146 mm and the wet weights ranged from 4.29 to 24.36 g. The stomach contents were removed and stored in ethanol for later analysis. The burbot were …


Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez Jan 2025

Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez

Journal of Earth and Life Science

Wild rice (mannoomin; Zizania palustris) is an aquatic grain that grows in slow-moving rivers and shallow bays throughout northern Minnesota. In Headquarters Bay on Leech Lake, wild rice has served as a cultural staple for Indigenous communities for centuries. However, its population has declined in recent years due to multiple environmental issues. One potential contributor is Eurasian watermilfoil (Myriophyllum spicatum; EWM), an invasive species that forms dense mats capable of outcompeting native aquatic vegetation, including wild rice. EWM was first recorded on the southern shoreline of Leech Lake in 2005 and has since become widespread. This study …


The Effect Of Zebra Mussels On Minnesota Fish Communities, Benjamin D. Strei Jan 2025

The Effect Of Zebra Mussels On Minnesota Fish Communities, Benjamin D. Strei

Journal of Earth and Life Science

Zebra mussels Dreissena polymorpha are an aquatic invasive species that has been spreading quickly throughout Minnesota water bodies since 1989. Zebra mussels are known to change certain morphological conditions in lakes such as turbidity, phytoplankton abundance, and aquatic invertebrate populations. However, studies showing impacts of the infestation of zebra mussels on the health of a fish community have been hard to prove due to a lack of repeated surveys and a suite of other confounding variables such as natural and seasonal variability, plant community, and lake morphometry. Therefore, the objective of this study is to determine whether zebra mussels have …


How Individual Traits Predict Distribution Patterns And Community Convergence, Zachary K. Lange Jan 2025

How Individual Traits Predict Distribution Patterns And Community Convergence, Zachary K. Lange

Biology Dissertations - Archive

One of the fundamental questions in biology is whether natural conditions lead species and communities toward predictable outcomes. Answering this question requires understanding how traits of individual organisms are connected to species- and community-level patterns. In Chapter 2, I examined how thermal physiology and environmental temperatures interact to determine the distribution patterns of Anolis lizards on the Greater Antilles. I combined lab-measured thermal traits (critical thermal minimum: CTmin, critical thermal maximum: CTmax, thermal preference: Tpref) with occurrence and abundance data from 21 species of Anolis lizards collected from extensive mark-resight surveys of communities across …


Size Of Age-0 Sander Vitreus Pre And Post Dreissena Polymorpha Infestation On Brainerd And Bemidji Area Lakes, Quady Bernu Jan 2025

Size Of Age-0 Sander Vitreus Pre And Post Dreissena Polymorpha Infestation On Brainerd And Bemidji Area Lakes, Quady Bernu

Journal of Earth and Life Science

Walleye Sander vitreus is the Minnesota state fish and a vital predator fish in lake ecology. Zebra mussels, Dreissena polymorpha were first found in Minnesota inland lakes in the 1980’s. These mussels have had huge impacts on water clarity as well as phytoplankton and zooplankton population levels which affect how age-0 fish feed, especially a low light feeding predator fish like walleye. A study took place on age-0 walleye size and it supported the conclusion that age-0 walleye were negatively impacted by zebra mussels in Minnesota’s large lakes. The goals of this study were to determine how the size of …


Microsatellites Reveal The Population Genetic Structure Of Yellow Perch In Minnesota, Megan Boche Jan 2025

Microsatellites Reveal The Population Genetic Structure Of Yellow Perch In Minnesota, Megan Boche

Journal of Earth and Life Science

When analyzing a population’s genetic makeup, looking at variation of individuals and populations is a crucial factor. The management of yellow perch will be aided by this information particularly in regard to stocking or relocation. Microsatellite loci were used to analyze the genetic population structure of yellow perch Perca flavescens within and among 29 sampling areas throughout Minnesota’s basins. Seven microsatellite DNA loci were evaluated, with heterozygosities ranging from 0.41 to 0.78. The Lower Mississippi basin samples showed higher numbers of alleles per locus and greater expected heterozygosities compared to other basins, with Lake Pepin (PEP) exhibiting the highest average …


Aquatic Invertebrate Populations In Roadside Wetlands In Relation To Water Characteristics, Ellen P. Isakson Jan 2025

Aquatic Invertebrate Populations In Roadside Wetlands In Relation To Water Characteristics, Ellen P. Isakson

Journal of Earth and Life Science

The continual habitat destruction and draining of wetland systems makes the need to understand the ecology of roadside wetlands all the more necessary. Roadside wetlands provide valuable habitat to countless aquatic invertebrates, which can provide insight into the health of the wetland system due to their diversity. The objective of this study was to analyze the populations of aquatic invertebrates in roadside wetlands in relation to water characteristics such as pH, salinity, conductivity, water depth and temperature, and dissolved oxygen. This was done by collecting samples of invertebrate populations from roadside wetlands, in addition to data on water quality characteristics …


The Chesapeake Pearl: A Proposal For An Environmental Public Art Installation, Samuel I. Reichard Jan 2025

The Chesapeake Pearl: A Proposal For An Environmental Public Art Installation, Samuel I. Reichard

Pitzer Senior Theses

In this thesis, I lay the foundation for an environmental art project along Chesapeake Bay. It includes an analysis of relevant literature and case studies, as well as a proposal for the project. The Chesapeake Pearl (working title) would be a 20-foot spherical aquarium that will visually display the water filtration capacity of eastern oysters and native seagrass, aiming to inspire curiosity around these organisms and the greater Chesapeake Bay ecosystem. The project exists at the intersection of environmental art and environmental education and seeks to promote learning and public engagement through visually demonstrating a scientific process, the water filtration …


Are There Predictable Shifts In Fish Communities Following Instream Habitat Restoration? A Multistream Analysis., Ryan A. Skowronski Jan 2025

Are There Predictable Shifts In Fish Communities Following Instream Habitat Restoration? A Multistream Analysis., Ryan A. Skowronski

Masters Theses

In the past two centuries, anthropogenic stressors have degraded the structure and function of streams by accelerating bank erosion, decreasing riparian buffer zones, and altering the natural flow regime. Habitat restoration has become a common mitigation strategy in response to stream degradation, though empirical research evaluating its effectiveness is lacking in the United States. This study investigated responses in fish community following habitat restoration in five restored, Illinois streams. We assigned fish species to habitat, trophic, and reproductive guilds based on their habitat preferences, feeding habits, and life history. Streams were separated into enhancement and removal groups for analysis. Shifts …


Parasite Communities Of Bluntnose Minnow (Pimephales Notatus) From Several Creeks In East Central Illinois, Md Rowshan Alam Jan 2025

Parasite Communities Of Bluntnose Minnow (Pimephales Notatus) From Several Creeks In East Central Illinois, Md Rowshan Alam

Masters Theses

Parasites of freshwater fish play a vital functional role in aquatic ecosystems, but the spatial and ecological determinants of their prevalence and characteristics are still poorly understood. The current study quantified the diversity, prevalence, and environmental determinants of whole parasite burdens in bluntnose minnows across multiple creeks in central Illinois. Fish sampling and the collection of stream habitat data were conducted during the summers of 2023 and 2024. Fish were examined for parasites using necropsy and histology. A total of 20,817 parasites, predominantly trematodes (Posthodiplostomum spp.), cestodes (Proteocephalus spp), and protozoans, were identified. The most prevalent and abundant …


Unraveling Reproductive Complexity: Integrative Assessment Of White Crappie Pomoxis Annularis Spawning Dynamics In Kentucky Lake, Emily A. Freeman Jan 2025

Unraveling Reproductive Complexity: Integrative Assessment Of White Crappie Pomoxis Annularis Spawning Dynamics In Kentucky Lake, Emily A. Freeman

Murray State Theses and Dissertations

In large reservoirs such as Kentucky Lake, White Crappie Pomoxis annularis exhibit complex reproductive dynamics, including variable annual recruitment and frequent skipped or partial spawning events. This study investigates the energetic and environmental factors influencing spawning success in Jonathan Creek, a northern embayment of Kentucky Lake. Using a dual sampling approach, I combined citizen science angler-caught fish during the pre-spawn with trap netting in shallow spawning areas to capture crappie during the full reproductive cycle. Physiological, biometric, and egg analyses revealed that spawning success was driven more by pre-spawn energetic conditions than by the conditions during the spawn. Elevated water …


The Future Of Shipping At The Biodiversity-Climate Nexus : Round Table Report, Mary S. Wisz, Fabio Berzaghi, Mikaela Gomez, Maud C. Quinzin, Renis Auma Ojwala, Emily Nuckolls Jan 2025

The Future Of Shipping At The Biodiversity-Climate Nexus : Round Table Report, Mary S. Wisz, Fabio Berzaghi, Mikaela Gomez, Maud C. Quinzin, Renis Auma Ojwala, Emily Nuckolls

Reports

This report presents the outcomes of a cross-disciplinary Round Table hosted by the World Maritime University (WMU) from May 13-15, 2024, in Malmö, Sweden. The event brought together 51 experts from academia, industry, NGOs, and international organizations, including the IMO, to explore shipping’s role at the biodiversity-climate nexus. The Round Table had a particular focus on the impacts of shipping that are currently unregulated or under-regulated, and opportunities to address biodiversity loss and pollution as the sector decarbonizes. The report highlights the need to apply comprehensive, ecosystem-based approaches to effectively manage shipping's impacts, including cumulative impacts, on the environment, people, …


Bioremediation In The Chesapeake Bay: Anthropogenic Ocean Acidification Mitigation In An Interactive Multi-Trophic Ecosystem, Cree Taylor Jan 2025

Bioremediation In The Chesapeake Bay: Anthropogenic Ocean Acidification Mitigation In An Interactive Multi-Trophic Ecosystem, Cree Taylor

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Zostera marina is a species of marine macrophyte that has been largely prioritized in past submerged aquatic vegetation (SAV) restoration initiatives within the Chesapeake Bay because of its 1) previous abundance, 2) demonstrated carbon burial abilities, and 3) observed ability for meadows of Z. marina to ameliorate low pH conditions. Due to the temperature variability and poor water quality in the Chesapeake Bay, Z. Marina beds have experienced several die-off events with limited capacity for regrowth. Ruppia maritima, an opportunistic species with tolerance to temperature shifts within the bay, may have the potential to maintain SAV coverage in areas …


Rejuvra's Effect On Soil Seed Banks, Blake J. Roeslein, Bryan Endress, Abby Mcmurtry, Akasha Faist Jan 2025

Rejuvra's Effect On Soil Seed Banks, Blake J. Roeslein, Bryan Endress, Abby Mcmurtry, Akasha Faist

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Invasive annual grasses are a major driver of grassland degradation globally. In perennial grasslands, invasion can heavily impact biodiversity, including potential changes to the soil seed banks. Seed banks, the living seeds stored in the upper soil column, play an important role in healthy systems, or can harbor invasive species. To reduce negative invasion outcomes, whether in the seed bank, or aboveground vegetation, pre-emergent herbicides are a commonly used tool for land managers. Pre-emergent herbicides work by targeting seeds as they germinate and begin emerging from the soil. Thus, our study asks 1) how does pre-emergent herbicide influence germination and …


Noaa Oceanic And Atmospheric Research Ocean Carbon Observing Science Plan Fy25 To Fy35, United States National Oceanographic And Atmospheric Administration Jan 2025

Noaa Oceanic And Atmospheric Research Ocean Carbon Observing Science Plan Fy25 To Fy35, United States National Oceanographic And Atmospheric Administration

National Oceanographic and Atmospheric Administration: Technical Reports and Related Materials

United States National Oceanographic and Atmospheric Administration oceanic and atmospheric research ocean carbon observing science plan for fiscal years 2025 through 2035.


Presence Of Potential Nursery Habitat For The Lemon Shark In Mississippi Coastal Waters, Lindsay K. Bomgardner, P. O. Grammer, Angie Hoover, Anna Millender, Jeremy Higgs, Jill M. Hendon, Michael J. Andres Jan 2025

Presence Of Potential Nursery Habitat For The Lemon Shark In Mississippi Coastal Waters, Lindsay K. Bomgardner, P. O. Grammer, Angie Hoover, Anna Millender, Jeremy Higgs, Jill M. Hendon, Michael J. Andres

Gulf and Caribbean Research

No abstract provided.


Oyster Horizons: Spatial Prioritization For Oyster Restoration At Alabama Living Shorelines, Trinity Henry-Jack, Aaron Bland, Christa Russell, Ronald Baker Jan 2025

Oyster Horizons: Spatial Prioritization For Oyster Restoration At Alabama Living Shorelines, Trinity Henry-Jack, Aaron Bland, Christa Russell, Ronald Baker

Gulf and Caribbean Research

No abstract provided.


Selective Nutrient Incorporation May Underestimate Heterotrophy Of A Mixotrophic Reef-Building Coral, Connor R. Love, Marleen Stuhr, Michael D. Fox, Veronica Z. Radice, Maoz Fine, Kelton W. Mcmahon, David L. Valentine Jan 2025

Selective Nutrient Incorporation May Underestimate Heterotrophy Of A Mixotrophic Reef-Building Coral, Connor R. Love, Marleen Stuhr, Michael D. Fox, Veronica Z. Radice, Maoz Fine, Kelton W. Mcmahon, David L. Valentine

Biological Sciences Faculty Publications

Mixotrophic reef-building corals acquire nutrition via photosynthate translocation from endosymbiotic microalgae and by heterotrophic prey/particle capture. Heterotrophy promotes resistance to, and recovery from, environmental stress, but quantifying coral heterotrophy remains difficult due to complex resource exchanges within the coral holobiont. We interrogated the response of multiple biomarkers to coral heterotrophy using fatty acid profiling and stable isotope analysis of Stylophora pistillata grown along a controlled feeding gradient from pure autotrophy to pure heterotrophy. We found that fatty acids and nitrogen were effectively incorporated into both coral host and symbiont tissues, while carbon, which is the primary target for conventional heterotrophy …


“Nice To See You”: Addressing Plant Awareness Disparity With Locally Specific Ecological And Cultural Plant Education, Cecilia Muecke Jan 2025

“Nice To See You”: Addressing Plant Awareness Disparity With Locally Specific Ecological And Cultural Plant Education, Cecilia Muecke

Pomona Senior Theses

Plants form the basis of life on Earth. However, due to the phenomenon of plant awareness disparity, a self-perpetuating cycle whereby plants are overlooked on an individual and global level ensues. Lack of plant awareness leads to a lessened emphasis on plants in sustainability and conservation as well as biology education, resulting in negative impacts on biodiversity and food security. The severity of plant awareness disparity is dependent on cultural context, and Indigenous and/or traditional societies are less likely to experience plant awareness disparity because of they are typically more connected to plants for their everyday needs. Native plants are …


Assemblage Structure Of Large Carnivorous Coral Reef Fishes At Shallow And Mesophotic Depths In Two Of The Largest And Most Isolated Marine Protected Areas In The Philippines, Rene A. Abesamis, Mikaela L. Salvador, Ryan Murray, Kymry Delijero, Segundo F. Conales, Jean T. Utzurrum, Christopher E. Bird, David T. Gauthier Jan 2025

Assemblage Structure Of Large Carnivorous Coral Reef Fishes At Shallow And Mesophotic Depths In Two Of The Largest And Most Isolated Marine Protected Areas In The Philippines, Rene A. Abesamis, Mikaela L. Salvador, Ryan Murray, Kymry Delijero, Segundo F. Conales, Jean T. Utzurrum, Christopher E. Bird, David T. Gauthier

Biological Sciences Faculty Publications

Overfishing remains a threat to coral reef fishes globally, with large carnivores often the most vulnerable. Marine protected areas (MPAs) can restore fish populations and biodiversity, but their impact has been understudied in mesophotic coral ecosystems (MCEs – extensions of shallow reefs from 30 to 150 m). We analyzed baited remote underwater videos recorded in 2016 to investigate the assemblage structure of large carnivorous fishes at shallow (4–12 m) and mesophotic (45–96 m) depths in two of the largest and most isolated MPAs in the Philippines: Tubbataha Reefs Natural Park (TRNP), a fully no-take MPA enacted in 1988; and Cagayancillo, …


‘Who’S Your Daddy?’: Ddradseq Parentage In Broodstock-Offspring Pairs Of Diadema Antillarum In A Population Restoration Initiative, Bianca R. Rosendahl Jan 2025

‘Who’S Your Daddy?’: Ddradseq Parentage In Broodstock-Offspring Pairs Of Diadema Antillarum In A Population Restoration Initiative, Bianca R. Rosendahl

Undergraduate Scholarship and Creative Works

In the early 1980s Diadema antillarum, or the long-spined urchin, was hit by a catastrophic mass mortality event across the western Atlantic and Gulf of Mexico, inclusive of the Florida Keys. The cause of this die-off event was likely triggered by a pathogen or environmental stressor that decimated native populations by up to 98%. The species has not yet fully recovered and is struggling with recruitment success which is why it may benefit from an ex-situ recovery program. In this study, I used single nucleotide polymorphisms (SNPs) to identify genetic variation and analyze parentage in a captive population of …


The Influence Of Bottom-Up And Top-Down Effects On The Density And Distribution Of Common Leopards In The Eastern Himalayas, Karma Choki Jan 2025

The Influence Of Bottom-Up And Top-Down Effects On The Density And Distribution Of Common Leopards In The Eastern Himalayas, Karma Choki

Electronic Theses and Dissertations

Leopards (Panthera pardus fusca) are widely distributed across Asia, yet their conservation is overshadowed by the conservation status of other flagship predators like tigers (Panthera tigris), in the Eastern Himalayas. Despite their ability to coexist with other large carnivores, leopard populations are shaped by intricate ecological interactions and increasing human pressures. This thesis investigates the abundance and density, habitat use, and drivers of persistence of leopards across Bhutan to inform multi-species carnivore conservation planning. My first chapter provides an overview of the ecological roles of large carnivores and how they persist on the landscape. I review the mechanisms that facilitate …


The Spatial And Temporal Dimensions Of Plant–Soil Feedback In Native Perennial Monocultures, Bret Lang Jan 2025

The Spatial And Temporal Dimensions Of Plant–Soil Feedback In Native Perennial Monocultures, Bret Lang

Electronic Theses and Dissertations

Plant-soil feedbacks (PSFs) describe how plants change their soil environment in ways that can either negatively or positively affect subsequent plant growth. In doing so, they offer an opportunity to connect ecological processes with agricultural practice. My dissertation examines PSFs created by native perennial monocultures, commonly used for native seed production, across time and space, and through soil legacies. Specifically, I focus on how plant species identity shapes both soil nutrient and soil microbial community responses. To address these questions, I conducted field experiments with monocultures of five forb species native to South Dakota and established plots with these species …


Dam It All: A Multi-Scalar Investigation Into The Ecological Role And Function Of Beaver Dams, Kenneth Larsen Jan 2025

Dam It All: A Multi-Scalar Investigation Into The Ecological Role And Function Of Beaver Dams, Kenneth Larsen

Dissertations, Master's Theses and Master's Reports

The central theme of this dissertation is ecological scaling, which examines how small, localized features, such as beaver ponds, contribute to large-scale watershed processes and how different modeling approaches at various scales reveal distinct insights. Through a combination of probabilistic modeling and high-resolution empirical research, this work demonstrates that small ponded systems, particularly those created by beavers (Castor canadensis), serve as critical biogeochemical control points, whose contributions to sediment and nutrient dynamics have been historically underestimated.

In Chapter 1, I contextualize this research within the broader fields of freshwater ecology, watershed modeling, and ecological restoration. I introduce the …


Using Environmental Dna Metabarcoding To Investigate Diversity And Seasonal Variation Of Fishes In Humboldt Bay, California, Johnathon M. Richardson Jan 2025

Using Environmental Dna Metabarcoding To Investigate Diversity And Seasonal Variation Of Fishes In Humboldt Bay, California, Johnathon M. Richardson

Cal Poly Humboldt theses and projects

This study applied environmental DNA (eDNA) metabarcoding to characterize fish diversity and temporal patterns in fish assemblage structure within Humboldt Bay, California. This work advances ecological understanding of Humboldt Bay’s ichthyofauna, regional natural history and ecosystem function. Over one year (February 2023–January 2024), triplicate surface-water samples were collected every two weeks from a fixed site in Humboldt Bay (n = 78). DNA was extracted from filters and amplified using MiFish 12S primers in six replicate PCRs per sample. Amplicon concentrations were normalized, pooled and sequenced on an Illumina MiSeq platform (2×150 bp). Sequences were processed using a custom bioinformatics pipeline, …