Other Ecology and Evolutionary Biology Commons^™

Occupancy Of The Little Grass Frog (Pseudacris Ocularis), An Overlooked Longleaf Endemic, In A Managed Landscape, Anna M. Humphrey

Theses, Dissertations and Capstones

Amphibians are declining globally, with many declines associated with habitat loss. The longleaf pine (Pinus palustris) ecosystem historically covered most of the southeastern United States and supports a host of endemic amphibians. This ecosystem has declined by over 97% in the last two hundred years and many associated species have declined with it. The Little Grass Frog (Pseudacris ocularis) is a longleaf pine endemic anuran that has been understudied and under-surveyed; almost no information is known on the ecology of this species and no population studies have been conducted. My goals were to create an acoustic …

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

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Evaluating The Use Of Baited Remote Underwater Video (Bruv) In Assessing Shark And Fish Populations In A Low Visibility Estuarine System, The Tolomato River, Fl, Usa, Sarah Worthington

UNF Graduate Theses and Dissertations

Recently, there has been increasing use of baited remote underwater video (BRUV) surveys for assessing shark and fish populations in marine ecosystems. This approach can be useful because it may provide a non-destructive, non-extractive, and cost-effective alternative to traditional fishing-based methods. However, to date, most studies using BRUVs have focused on their use in high-visibility ecosystems, such as tropical reefs. Furthermore, few studies have compared results from BRUV surveys with those obtained using traditional methods to evaluate the efficacy of this approach. Therefore, the goal of this study was to evaluate the effectiveness of using BRUV surveys to assess shark …

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 …

Social Interactions And Spatial Structure Drive Community Assembly Of Bacterial Biofilm, Matthew C. Bond

Dartmouth College Ph.D Dissertations

Despite the critical nature which microbial communities play in the natural world and human civilization, the breadth of understanding remains shallow. Challenged by scale, high variability between environments, and extensive diversity, microbial ecologists strive to understand connections between a community’s structure and function, as well as the ecological and evolutionary mechanisms underlying observed natural patterning of communities. Biofilms are the predominate mode of growth for microbial communities—characterized by cellular attachment to a surface via a self-produced matrix and heterogeneous structure, often resulting in a primary growth front along the biofilm surface due to differential access to bulk nutrients (cite). This …

Stable Isotope Analysis Of Antipatharian Diets From The Northwestern Gulf Of Mexico, Keir J. Macartney, Victoria Salinas, Zachary Rivera, David Hicks

Gulf and Caribbean Research

Antipatharians, or black corals, form a key component of the benthic fauna found throughout the Gulf of Mexico (GOM). In the northwestern GOM, they are a common member of the communities found on the natural relic coral—algal banks known as the South Texas Banks as well as on artificial reefs. They are known to provide important habitat for many ecologically and economically important species in the area but are relatively understudied. Here we present a study on their trophic ecology using stable isotope analysis of carbon and nitrogen from 2 species, Antipathes atlantica and Stichopathes luetkeni from a mesophotic artificial …

Measuring Nature’S Contributions To People Provided By Species In The Gulf Of Maine Rocky Intertidal Ecosystem, Madelyn L. Eippert

Honors Theses

Ecosystem services aim to quantify the value of nature provided to humans. However, Ecosystem services are typically measured at the level of the ecosystem as a whole and do not consider interactions between species in an ecosystem. Ultimately, the species in an ecosystem determine the services that are provided. Measuring ecosystem services at the landscape level misses the complex interactions and changing biodiversity of ecosystems. Currently, there is no accepted framework to link ecosystem services to species. In this thesis, I developed a framework to link Nature’s Contributions to People (NCP) to species. NCP includes 18 specific contributions (i.e. 18 …

The Genetic Diversity Of An Endangered Buttercup, Ranunculus Triternatus, Ryan Garcia

All Master's Theses

Ranunculus triternatus, a rare endemic species of the Columbia River Gorge, faces conservation challenges due to its limited range and fragmented populations. This study assesses the genetic diversity of R. triternatus and compares it with its widespread congener, Ranunculus glaberrimus, using inter-primer binding site (iPBS) markers. Genetic data from 80 individuals across eight populations were analyzed using Nei’s genetic diversity, Shannon’s diversity index, and AMOVA. Results showed R. triternatus had higher genetic diversity than western populations of R. glaberrimus, with eastern populations of R. glaberrimus displaying greater diversity than western ones. PCA, UPGMA, and STRUCTURE analysis revealed …

The Role Of Neighborhood Effects In Maintaining The Hardwood-Hemlock Mosaic, Adam Z. Milenkowic

Dissertations, Master's Theses and Master's Reports

Neighborhood effects are processes mediated by canopy trees that influence the ability of a species to replace itself following canopy mortality. Sugar maple (Acer saccharum Marsh.) and eastern hemlock (Tsuga canadensis (L.) Carr.) are the dominant trees in old-growth northern hardwood forests of Upper Michigan and have been observed to form monodominant patches in the region. Few studies have independently evaluated the demographic and ecological mechanisms that lead to the compositional stability of hemlock and sugar maple patch development. Tree demography data from eight long-term 0.5 ha old-growth plots in Upper Michigan indicate neighborhood effects are playing a …

Scale And Habitat Effects On Measurement Of Streptomyces Biogeography And Biodiversity, Terilyn A. Stoflet

Cal Poly Humboldt theses and projects

Bacteria in the genus Streptomyces are detected in most soils around the world, as well as on and in seeds, plants, animals, insects and the wind. Currently, more than 700 valid species of Streptomyces have been identified worldwide. Streptomyces produce the majority of antibiotics, antivirals and antifungals, as well as important agricultural bioactive molecules due to their unique genetic capabilities. Their distinct genetic abilities allow them to produce an unlimited amount of biosynthetic gene clusters, or BGC’s. Although many compounds come from Streptomyces, scientists have not discovered the biogeographic patterns of this genus. The biogeography of Streptomyces is a …

Bird Predation On Coho Salmon (Oncorhynchus Kisutch) In Humboldt Bay, Colton J. Dixon

Cal Poly Humboldt theses and projects

Coho Salmon (Oncorhynchus kisutch) populations along the west coast of the United States are declining. In Humboldt County, located in northwestern California, Coho Salmon have been in decline since their federal listing as threatened in 1997, primarily due to habitat loss from logging, agriculture, and urban development. Although these anthropogenic factors caused salmon populations to decline, bird predation may also be hindering population recovery, as evidenced by the recovery of Passive Integrated Transponder (PIT) tags, originally implanted in Coho Salmon, from bird colonies in Humboldt Bay. This study examines predation by Double-crested Cormorants (Phalacrocorax auritus), Caspian …

A Balancing Act: Microrna Mediated Insect-Bacterial Homeostasis And The Tsetse Fly, Mason Hubbard Lee

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microbial symbioses are ubiquitous across all kingdoms of life with broad and diverse impacts on the evolution of species. The sum of all microbes living in, on, or otherwise in close association with a host form the microbiota. In some cases, the development of a stable microbial association seems to have been necessary for the specialization of diet, as can be observed in numerous insect species, especially wood-eating, sap-feeding, and blood-feeding organisms. For the medically and economically tsetse fly (family Glossinidae), the mutualistic bacteria Wigglesworthia glossinidia is required for proper reproduction and supplementation of nutrients that the fly does not …

The Smell Of Fear: Responses Of Native And Invasive Geckos To Predator Scent Cues On Moorea, French Polynesia, Haley Dreisbach, Tessa Bodo

Williams Honors College, Honors Research Projects

Hemidactylus frenatus, a globally invasive species, is syntopic with the native gecko Lepidodactylus lugubris on the island of Moorea, French Polynesia. The success of an invasive species, H. frenatus can be attributed to many factors and is the subject of much study. Some research suggests that invasive and native geckos may differ in their response to chemosensory cues from predators. We compared the responses of H. frenatus and L. lugubris to the scents of both a native local predator; centipede, and a common predator of geckos that is not present on Moorea; snake. While neither gecko species showed any …

The Effects Of Native Perennial Cover On Physiological Indicators Of Habitat Quality For Sparrows In California Coastal Prairie Rangelands, Madeleine A. Ybarra

Cal Poly Humboldt theses and projects

Prescribed grazing management can have myriad effects on wildlife, with low to moderate grazing being associated with an increased abundance of some grassland birds. Specifically, Grasshopper Sparrow (Ammodramus savannarum) and Savannah Sparrow (Passerculus sandwichensis) abundance have been shown to be positively associated with both grazing and a higher percentage of native plant cover. However, measures of abundance provide an incomplete assessment of habitat quality for birds. Physiological and morphological measurements can help indicate environmental stress in individual birds, which reveals more information about habitat quality. We measured body condition and heterophil:lymphocyte ratios to gauge avian stress …

Fire Severity Mediates Marten And Fisher Occurrence: Impacts Of The Dixie Fire On A Carnivore Community, Christopher James Collier

Cal Poly Humboldt theses and projects

The consumption of an astounding one million acres resulted from California’s largest single fire to date, the 2021 Dixie Fire. The social and economic losses associated with the fire were immediately apparent, but the effects on wildlife remained unknown. While previous research has suggested mixed or low severity fire may be beneficial to certain wildlife species, the responses to megafires are poorly understood for many carnivores. To better understand these responses to severe fire, I used a random sampling design stratified by burn severity to survey in and around the Dixie Fire footprint using baited camera stations. This allowed me …

Habitat Selection And Connectivity Of Mountain Lions (Puma Concolor) Across Anthropogenic Barriers On The Olympic Peninsula: A Multi-Method Comparison, Thomas R. Barbee

Graduate Student Theses, Dissertations, & Professional Papers

Designing and maintaining effective wildlife corridors is an increasingly important conservation challenge in today’s fragmenting landscapes. GPS-based resource selection functions and camera-based occupancy models are both well-established staples of wildlife connectivity analyses and corridor planning, but each have notable trade-offs in cost and data resolution. Wildlife organizations worldwide rely heavily on camera-based occupancy modelling to plan wildlife corridors, especially where resource limitations or ethical concerns prohibit the use of GPS tags. If spatial connectivity maps from occupancy models could be shown to capture the essential elements of animal movement well enough to identify functionally equivalent corridors to those identified in …

Maximum Entropy Species Distribution Modeling For The Spring Ephemeral Herb Bloodroot (Sanguinaria Canadensis) In Eastern North America, Velan Manivannan

Williams Honors College, Honors Research Projects

The spring ephemeral plant Bloodroot (Sanguinaria canadensis) has a widespread native range in North America, spanning much of the eastern United States and Canada. While its current NatureServe conservation status is designated as ‘secure’ (NatureServe, 2023), its status as a spring ephemeral places it at a heightened risk for climate change-induced phenological mismatch with advancing forest canopy closure. Additionally, under continued anthropogenic climate change, Bloodroot may also experience range shifts or contractions as the edges of its present range warm past physiological thresholds. To determine the potential for range shifts and contractions under future warming, I generated a …

Interdisciplinary Learning: How Different Ways Of Thinking Can Fuel Passion And Expand Understanding., Allison Amy Peschek

Undergraduate Theses, Professional Papers, and Capstone Artifacts

This Capstone project was created to show the profound experience resulting from an extended range of interdisciplinary learning, and how different methods, when paired together, can enhance a learning experience. This was a personal project of exploration into those different angles, and primarily focused on avenues of logical and creating learning, respectively. These methods have been implemented by this author often in the past, but this capstone will explore this concept further, as there is a lot of potential in combining these different methods and biases in learning, to both further passion and understanding as a learner, but to also …

An Effective Method For Long-Term Control Of American Bullfrogs Syntopic With Special-Status Native Amphibians In California, Usa, Jeff A. Alvarez, Jeffery T. Wilcox

Human–Wildlife Interactions

American bullfrogs (Lithobates catesbeianus) are invasive in western North America and are well established in California, USA, where they are widespread. This invasive species has been implicated in the decrease of native amphibian populations and is believed to have contributed to the decline of threatened and endangered amphibians regionally. We utilized air rifles, tin alloy pellets, and 2 shooters to systematically control L. catesbeianus in both lentic and lotic habitat types within 2 counties in California. We visited sites monthly (April through November) for approximately 8 and 14 years to lethally target and remove L. catesbeianus …

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 …