Terrestrial and Aquatic Ecology Commons^™

Are Elaeagnus Umbellata Invasions Limited By Microbial Interactions?, Cody Anderson Leverette

Masters Theses

Mutualistic interactions with soil microbes are a key component of plant invasions. Mutualists such as ectomycorrhizal fungi and Rhizobia bacteria often limit invasive plant establishment and performance, but the role of nitrogen-fixing Frankia bacteria in invasions remains largely unexplored. In this study, I quantified the net effects of positive and negative plant-soil feedbacks, including Frankia nodulation, on invasive Elaeagnus umbellata (autumn olive; hereafter AO) seedling performance and traits at varying distances from focal shrubs using live soil and sterilized soil. The expectation was that seedling performance would decrease with further distance from shrubs as Frankia abundance decreased. Contrary to expectations, …

Benthic And Epibenthic Invertebrate Assemblages Associated With Estuarine Submerged Aquatic Vegetation Differ Between Native And Invasive Plants, Marissa Hall, Kathryn O'Shaughnessy, Bethany Kiley, Ashley Mcdonald, Taber Faurie, Zoey Hendrickson, Anna Reimer, Samantha Smith, Charles Martin

Gulf and Caribbean Research

Estuarine submerged aquatic vegetation (SAV) provides vital habitat for macroinvertebrate communities that support diverse food webs and subsequent ecosystem services. Invasive SAV, however, has the potential to alter estuarine food webs through competition with native SAV, resulting in different associated biological communities. In the Mobile-Tensaw Delta (Alabama, USA), the invasive Eurasian milfoil, Myriophyllum spicatum, is fast becoming the dominant SAV, out-competing native SAV such as wild celery, Vallisneria americana. This study investigated the above- and belowground macroinvertebrate assemblages associated with these SAV habitats. We found significantly different assemblages between the SAV, with V. americana supporting more even and …

Walleye (Sander Vitreus) Do Not Exhibit An Aggregative Predatory Response To Larval White Sturgeon (Acipenser Transmontanus) In The Upper Columbia River In Lake Roosevelt, Washington, Seth A. Barr

EWU Masters Thesis Collection

Seasonal prey abundance can drive predatory fishes to aggregate in areas of high prey density. This project aimed to determine whether Walleye (Sander vitreus) exhibit an aggregative predation response to larval White Sturgeon (Acipenser transmontanus) drifts in the Lake Roosevelt system which is a reservoir of the Columbia River in Washington State. Populations of sturgeon are threatened worldwide, and are in need of conservation research. Walleye are a popular nonnative piscivorous game fish that were accidentally or illegally introduced to Lake Roosevelt in the 1950’s. Walleye in this study were obtained by gillnetting during White Sturgeon pre-spawn, peak spawn, and …

Moose Abundance And Calf:Cow Ratios On The Blackfeet Indian Reservation And Glacier National Park, Landon Joel Magee

Graduate Student Theses, Dissertations, & Professional Papers

Many moose (Alces alces; Sikihtsisoo) populations across North America, especially along their southern range, are declining due to factors such as climate change, parasites and disease, predation, habitat loss and degradation, and overharvest. These declines highlight broader ecological concerns, as moose play a critical role as prey within their ecosystems. Despite their importance, data on crucial demographic parameters like abundance and age ratios are sparse for moose, complicating management efforts. Conventional monitoring methods, including radio-collaring, harvest data, public surveys, and aerial surveys, face significant logistical and financial challenges, and often fail to provide a comprehensive understanding of …

Methods For Optimizing Detection And Evaluating Habitat Use Of North American River Otters In South Dakota, Jessica Speiser

Electronic Theses and Dissertations

North American river otters (Lontra canadensis) play a critical role as an apex predator in riverine ecosystems. A challenging species to survey using traditional methods, they remain understudied in non-forested regions, such as the Northern Great Plains, where habitat degradation and landscape fragmentation may reduce habitat quality and availability and disrupt landscape connectivity. This thesis aims to improve detectability and investigates the habitat use of river otters in South Dakota to better understand habitat needs of otters and improve their continued recovery and management. My first chapter provides a brief overview of river otters and their ecological roles in freshwater …

Improving Stream Connectivity In South Dakota, Colton Rainier Curtis

Electronic Theses and Dissertations

Stream connectivity is crucial for fish movement and genetic diversity in fragmented landscapes. Road-crossings often act as barriers, disrupting hydrology and isolating fish populations. The Southeast Aquatic Resources Partnership (SARP) has developed rapid road-crossing assessment protocols and tools to prioritize restoration projects. However, managers lack tools for planning, directing, and initiating roadcrossing assessments. Managers also require modeling approaches to effectively identify and monitor road-crossings across dynamic stream networks. Presented here is a case study offering a roadmap for effective implementation of collaborative road-crossing assessments and prioritization of remediation projects, alongside an exploration of predictive modeling approaches to identify problematic crossings …

Dust Management At An Active Construction Area Affects Monarch Distribution, Amy W. O'Donnell, Jeffery D. Sullivan, Carl R. Callahan, Peter C. Mcgowan, Diann J. Prosser

Human–Wildlife Interactions

The North American population of monarch butterflies (Danaus plexippus) is experiencing dramatic declines, necessitating investigations into challenges facing this species that can be resolved through management actions. For instance, dust made airborne by heavy equipment driving along a dirt road can settle on roadside vegetation, resulting in reduced use by monarchs. Dust accumulation on areas where floral nectaries such as leaves, stems, and flowers may be present could reduce the ability of pollinators, such as monarchs, to access nectar from flowering plants needed during migration. One such challenge was observed on Poplar Island, an island restoration project located in …

Integrating Western Science And Indigenous Knowledge For Just Practices In Conservation, Cierra Lea Keith

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Interactions Between New Zealand Mud Snails (Potamopyrgus Antipodarum) And Toxic Cyanoabacteria (Anabaena) In Baduwa’T (Mad River), Humboldt County, California, Cecilia F. Kennelly

Cal Poly Humboldt theses and projects

Invasive species in freshwater systems are circulated around the globe, wreaking havoc on natural communities. The New Zealand mud snail (Potamopyrgus antipodarum) is a very successful aquatic invader that has established populations in freshwater streams, lakes, and rivers around the globe. The goal of this project was to evaluate the interactions of invasive New Zealand mud snails (NZMS) and toxic cyanobacteria Anabaena in the Mad River in Humboldt County, California. These two species of concern are found in similar habitats along the river, but their whether NZMS consume Anabaena or affect toxin production is unknown. First, I conducted …

Examining Wrack In Mosquito Lagoon To Analyze Biodiversity And Seagrass Viability, Nicole Jerrell

Honors Undergraduate Theses

Seagrass restoration of Halodule wrightii, has become crucial as seagrass coverage in the Indian River Lagoon (IRL) declined by 58% between 2011 and 2019. To understand the abundance of seagrass fragments available for natural recruitment and restoration, we tracked the abundance of viable fragments found in the wrack in Mosquito Lagoon. Wrack is plant material, including seagrass fragments, mangrove propagules, and detritus. Seagrass fragments were considered viable if the fragment had an apical meristem present. Replicate samples were collected from 5 locations every two weeks, starting in September 2022 and ending in September 2023, and the samples were processed …

Endophytic Fungi Associated With Galls And Host Plants Of Asphondylia Borrichiae (Diptera: Cecidomyiidae), Shannon Lynn Sharpe

UNF Graduate Theses and Dissertations

Asphondylia borrichiae, like other gall-forming gnats, are obligate symbionts to the endophytic fungi (EF) they deposit when laying eggs. Asphondylia spp. and EF are important biocontrol agents, yet details surrounding their diversity, life cycles, and host interactions remain poorly understood. Galls and leaf-stem tissues from two host plants were surveyed to identify and compare EF diversity between the host tissues and species of A. borrichiae. Identification of 114 isolates was carried out by sequencing the internal transcribed spacer (ITS 1/4 primers). Pairwise alignments in multiple genetic databases were bolstered by phylogenetic analyses using maximum parsimony and maximum likelihood …

Monitoring Faunal Responses To Biodegradable Oyster Reef Restoration Materials With Camera Traps, Tara L. Blanchard

Honors Undergraduate Theses

Restoration of the oyster reefs has become increasingly crucial due to great population declines around the globe. Intertidal oyster reefs provide essential foraging and loafing grounds to many faunal species, including several threatened/endangered wading bird species. Biodegradable oyster reef restoration materials have been introduced to avoid potential plastic pollution from traditional materials. Studies have shown success regarding oyster recruitment rates to these materials. However, their impacts on fauna using restored oyster reefs are unknown. This project aims to evaluate oyster reef restoration using biodegradable materials to increase faunal diversity, abundance, and foraging behaviors. Camera traps were deployed to observe fauna …

Leaf To Canopy Functional Resilience: Plant Physiological And Carbon Cycling Stability Following Disturbances, Lisa T. Haber

Theses and Dissertations

Ecological disturbances impact core ecosystem functions, including production and biogeochemical cycling, by precipitating changes in biodiversity, physical environmental variables, vegetation structure, and functional trait distributions. As disturbance patterns intensify and abruptly transition to novel regimes under global change, future trajectories of ecosystem functions, including carbon (C) uptake and storage, are uncertain. A more complete understanding of the mechanisms underpinning ecosystem stability (or ability to return to baseline functioning) following disturbance is needed to forecast future C cycling.

Replicated ecosystem-scale disturbance experiments, particularly when coupled with modeling, are required to rigorously test hypothesized trajectories of ecosystem structural and functional change following …

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

Dissertations, Master's Theses and Master's Reports

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

Targeting Macrophytes: Increased Water Quality Through Optimized Vegetation Considerations For Constructed Wetlands, Austin Mcbrady

Masters Theses (Archived)

This study of constructed wetland design investigated relationships between macrophyte species selection and planting density for water quality improvement. A lab-scale wetland was compared against a pilot-scale wetland in San Antonio, Texas at Mitchell Lake to measure differences in effluent water quality improvement using three native macrophyte species. Using a novel, two-phase method, a targeting macrophyte was identified from among other species based on its marked capability for improving water quality factors, then was planted in varied majority densities to compare differences in treatment effectiveness. The results of this study showed that this complimentary approach to wetland design displayed significant …

Tropicalization Fact Sheet, Linda Walters, Carla Perscky

CEELAB Outreach Materials

The goal of this 2-sided fact sheet is to introduce the topic of tropicalization along our coastlines to young audiences and their families. Tropicalization is defined as, "the transformation of ecosystems by tropical organisms that migrate towards the poles in response to warming minimum winter temperatures."

Population Trends And Trophic Ecology Of The Invasive Peacock Eel (Macrognathus Siamensis) In The Florida Everglades, Grace Kahmann

Electronic Theses and Dissertations

Invasive species threaten the ecological integrity of ecosystems worldwide, including the Florida Coastal Everglades. This study investigated the ecological role of the peacock eel (Macrognathus siamensis) within this ecosystem, emphasizing its population trends and the environmental factors that affect its population performance, and the potential for interactions with native fish assemblages and coastal food webs. I used 19 years of electrofishing data to investigate the population trends of peacock eels at the marsh-mangrove ecotone of the Shark River Estuary, Everglades National Park (Florida, USA). I found that peacock eel populations have increased since their first detection in 2002, and their …

Genomic Analysis Reveals New Species And Subspecies Of Butterflies, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Large-scale genomic sequencing of butterfly taxa reveals new findings that are presented here. While we focus on detecting species by comparative genomics and define subspecies as groups of populations genetically differentiated from each other but not as strongly as species (that is, subspecies as species in the making), we report other adjustments to butterfly classification. As a result, 4 subgenera, 11 species, and 6 subspecies are proposed as new. New subgenera are: Rapis Grishin, subgen. n. (type species Papilio rapae Linnaeus, 1758, genus Pieris Schrank, 1801) in Pieridae Swainson, 1820 and Callitera Grishin, subgen. n. (type species Eurygona? pulcherrima …

Reassessment Of Amblyscirtes Hegon (Hesperiidae) As A Complex Of Four Distinct Species Revealed By Genomic Analysis, Harry Pavulaan, Ricky Patterson, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

After the discovery of a unique phenotype in the southern United States with a different ventral ground color than nominotypical Amblyscirtes hegon (Scudder, 1863), which occurs in the northeastern United States, genomic analysis revealed that A. hegon is a species complex. Phenotypic, genitalic, and genomic differences of the complex are presented here. Four species are identified: A. hegon; A. nemoris (W. H. Edwards, 1864), stat. rest.; A. matheri Patterson, Pavulaan & Grishin, sp. n. (TL: USA, Mississippi, Warren County); and A. gelidus Grishin, Patterson & Pavulaan, sp. n. (TL: USA, Michigan, Van Buren County).

Habitat Utilization Of Marsh And Adjacent Submerged Landscape By Fish And Macroinvertebrates In A Gulf Of Mexico Tidal Oligohaline Environment, Tia Offner

Theses and Dissertations

Estuarine habitats are considered nursery habitats for fishes and invertebrates, but oligohaline environments are critically understudied. Using a seine net and fyke nets, we sampled Back Bay, Mississippi (USA), a low salinity estuary, once a month for a year to explore the temporal use of the marsh and adjacent submerged landscape by nekton species. We also looked at whether there is evidence of habitat preference in the most numerous nekton species. We used a novel habitat usage index (HUI) to compare seine and fyke net catches of our top 10 species, and evaluated catch size in relation to maturation size. …