Ecology and Evolutionary Biology Commons^™

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 …

Informing Standardized Wood Turtle (Glyptemys Insculpta) Population Monitoring: Influences Of Sampling Approach And Turtle Behavior On Model Estimation, Allyson N. Beard

Graduate Theses, Dissertations, and Problem Reports

To better understand wood turtle (Glyptemys insculpta) population trends, two standardized population survey protocols were recently developed for use by state monitoring programs. The protocols were independently developed, tested, and deployed for population monitoring in the eastern and upper midwestern United States. It was unknown if the sampling designs result in similar detection success or if data from the two protocols are compatible for broad-scale analyses. Additionally, neither monitoring protocol includes a sampling design that allows for the separation of detection (p) into availability (p_a), and detection given availability (p_d). …

Effects Of Land Cover Changes And Hydropower Development On Fish Communities In Amazonian Floodplain Rivers, Samuel Baron Grinstead Hessburg

Graduate Theses, Dissertations, and Problem Reports

In Amazonian River systems, diverse fish communities depend on the floodplains for providing feeding opportunities and critical spawning habitat during the seasonal flood pulse, which annually submerges floodplain forests. In the Amazon, large-scale deforestation and hydroelectric dam construction can have profound impacts on entire ecosystems by altering river-floodplain connectivity. This study attempts to improve understanding of Amazonian fish responses to these two stressors. The first chapter aims to understand how deforestation impacts floating meadow fish assemblages. For this study, we surveyed fish in floodplain lakes along the lower Amazon River, recording their abundance in relation to forest cover and local …

Factors Associated With Acoustic Bat Presence During Spring Emergence In The Appalachian Mountains Of Western Virginia, Emily Kirk Pody

Theses, Dissertations and Capstones

Studies of threats that bats face during hibernation have increased in response to white-nose syndrome (WNS), a fungal disease that has ravaged North American bat populations. However, impacts of WNS on bat ecology during spring emergence, when bats are potentially recovering from infection and allocating resources for reproduction, is relatively understudied. As more bat species become listed at the federal and state level, the need to understand the factors associated with spring emergence is critical for improving conservation guidelines and habitat management practices. Acoustic monitoring is an efficient method for monitoring bat presence for prolonged periods of time, giving biologists …

Estimation Of Probability Of Habitat Use Of Roosevelt Elk On The Olympic Peninsula, Vincent Michael Gugliotti

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Estimating the probability of habitat use for a particular species is crucial to the direct management and conservation of that species. Without knowledge of habitat preferences, managers cannot effectively focus efforts on vital resources or landscape types. However, modelling probability of habitat use can be done in several ways which leaves room for variation and uncertainty in the estimates produced by each method. This study is an examination of the variation between two estimates of probability of habitat use while focusing on a particular subspecies of elk that inhabits a unique ecosystem relative to other elk subspecies. I modeled elk …

The Genetic Basis Of Two Reproductive Traits In Monkeyflowers: Stigma Closure And Corolla Carotenoids, Rachel Anne Halperin

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Abstract

The interactions between pollinators and flowers have long been a driving force for the evolution of many physical floral traits. Traits such as flower shape, size, color, and smell are just some of these traits that evolve because of these interactions. This evolution does not only occur in the more obvious morphological floral traits, however, but also in more subtle traits like touch sensitive stigma closure. In hundreds of Lamiales species, the bilobed stigma, the organ that receives pollen from pollinators, closes rapidly upon touch. Theory and experiments show that this novel dynamic reproductive trait increases pollen export and …

Screening H3 Histone Acetylation In A Wild Bird, The House Sparrow (Passer Domesticus), Daniella Ray

Electronic Theses and Dissertations

Epigenetic mechanisms are increasingly understood to have major impacts across ecology. However, one molecular epigenetic mechanism, DNA methylation, currently dominates the literature. A second mechanism, histone modification, is likely important to ecologically relevant phenotypes and thus warrants investigation, especially because molecular interplay between methylation and histone acetylation can strongly affect gene expression. There are a limited number of histone acetylation studies on non-model organisms, yet those that exist show that it can impact gene expression and phenotypic plasticity. Wild birds provide an excellent system to investigate histone acetylation, as free-living individuals must rapidly adjust to environmental change. Here, we screen …

Movement Behavior And Metapopulation Connectivity Of Stream Salamanders In Response To Disturbance Events, Kathryn M. Greene

Theses and Dissertations--Biology

Metapopulations are shaped by the dispersal between populations in a landscape. Disturbance events can disrupt this connectivity resulting in local population extinction. For my dissertation, I used a combination of empirical and theoretical techniques to examine dispersal in response to disturbance and assessed it’s population-level consequences. My research used capture-mark-recapture sampling techniques to evaluate stream salamander movement in response to (1) a supraseasonal drought and (2) mountaintop-removal-mining (MTR) and valley-filling (VF) and (3) agent-based simulation modeling to evaluate population extinction risk in response to varying dispersal and mortality rates.

First, I evaluated the effects of a supraseasonal drought, a severe …

Using Novel And Traditional Survey Techniques To Monitor Small Mammal Species In Northwestern California, Sydney Mccluskey

Cal Poly Humboldt theses and projects

Small mammal species play a critical role in forest ecosystems contributing significantly to overall forest biodiversity and ecological dynamics. Forest-dwelling species are among the most vulnerable to habitat loss and fragmentation. It is essential to develop efficient techniques for monitoring small mammal populations in forested ecosystems to inform conservation efforts and management plans; yet, monitoring small mammals in these habitats can be particularly challenging due to their size, activity patterns, and frequently nocturnal nature. In this study, I aimed to address two primary research objectives: 1) compare the effectiveness of 3 distinct camera-trap survey techniques (i.e., ground, tree, and tube) …

Characterizing The Habitat Use Of Pacific Coast Feeding Group Gray Whales (Eschrichtius Robustus) And The Spatial And Temporal Variability Of Their Benthic And Planktonic Invertebrate Prey In Northern California, Robyn E. Norman

Cal Poly Humboldt theses and projects

As opportunistic foragers, the Eastern North Pacific population (~20,000) of gray whales (Eschrichtius robustus) feed on diverse benthic and planktonic invertebrates in northern Alaska foraging grounds before they undertake one of the largest yearly migrations of any mammal to breed in Baja California, Mexico. While most of the population travels to the summer foraging grounds in Alaska, a sub-group of whales (~230) called the Pacific Coast Feeding Group (PCFG) summer between British Columbia, Canada, and northern California. The diet of PCFG whales typically includes high-density and/or high-caloric prey items like mysids and diverse species of amphipods, yet a …

Microbes: Key Constituent Of Predator Risk Cues?, Jake R. Vargas

Cal Poly Humboldt theses and projects

Chemical cues emanating from predators can play a key role in aquatic predator-prey interactions and food webs. Understanding how prey respond to these risk cues is therefore critical for understanding the direct effects of predators on prey populations and their indirect effects on communities. To respond adaptively, prey must accurately assess the risk of predation associated with perceived chemical cues, an oft-documented phenomenon. However, little is known about how cues disperse, persist, and degrade, all of which could limit the adaptive responses of prey. Using laboratory-based observations of a well-studied predator cue-induced antipredator behavior by the marine gastropod Tegula funebralis …

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 …

Pond Characteristics That Influence Oviposition Site Selection By Two Pond-Breeding Amphibians, Northern Red-Legged Frog (Rana Aurora) And Northwestern Salamander (Ambystoma Gracile), Jessica Jones

Cal Poly Humboldt theses and projects

Pond-breeding amphibians connect aquatic and terrestrial habitats through their biphasic life cycle, and understanding pond characteristics that support oviposition sites for multiple species is important for amphibian conservation. Two common amphibians in the Pacific Northwest, Northern red-legged frog (Rana aurora) and Northwestern salamander (Ambystoma gracile) often oviposit in the same pond; however, prior studies have focused on pond use by one species or the other, but not both together. I surveyed pond and oviposition site characteristics of 26 ponds in Humboldt County, CA, 10 of which were used only by R. aurora and 16 of which …

Herbicide Management Alters Fungal Biomass And Community Composition In Great Lakes Coastal Wetlands, Erica Danae Lathers

Master's Theses and Doctoral Dissertations

Wetlands provide many ecosystem services, and invasive species and their management can alter these services. Plant responses to wetland management actions are typically monitored, but less is known about how soils respond. Phragmites australis, an invasive wetland plant, can alter soil conditions, potentially impacting soil microbial structure and function. We sampled soil communities in Great Lakes coastal wetlands in southeastern Michigan dominated by Phragmites and sites that had been previously invaded by Phragmites then treated with herbicide from 2011-2017, to understand how herbicide management alters soil fungal communities. We assessed microbial and fungal biomass, fungal community composition, greenhouse gas emissions, …

Looking For Love On A Chilly Night: The Colorado Brown Tarantula Mating Season, Dallas Haselhuhn

Master's Theses and Doctoral Dissertations

Aphonopelma hentzi is the most widespread and abundant tarantula species in the United States. While a distinct mating season is observed, it has not been well studied and the environmental drivers for the mating season are unknown. By conducting daily surveys on a peripheral population within Southeast Colorado, between August and November 2022, I found that after the first significant temperature drop, the number of mate-seeking males was significantly higher than prior to this temperature event. Mate-seeking males were significantly correlated with a drop in the water vapor pressure gradient, a rarely used biological metric for assessing potential water loss …

Estructura Y Aspectos Funcionales De La Comunidad De Hormigas En Bosques De Galería De La Hacienda Matepantano, Yopal - Casanare, Colombia, Henry David Mosquera Daza

Biología

Los bosques de galería de la Orinoquía colombiana, esenciales corredores biológicos que permiten la dispersión de la fauna y flora, han sufrido una reducción significativa en los últimos 31 años debido a la expansión agrícola. En respuesta a esto, se han utilizado las comunidades de hormigas como indicadores del estado del bosque, ya que su estructura y función reflejan la diversidad del hábitat. En ese sentido, este estudio busca describir la estructura y los aspectos funcionales de la comunidad de hormigas en los bosques de galería de la Hacienda Matepantano, Yopal-Casanare, durante el periodo de transición estacional.

Factors That Influence Small Mammal Long Bone Morphology: An Analysis Of The Femora, Tibiae, And Humeri Of The Eastern Gray Squirrel (Sciurus Carolinensis), Tyler Everette Blake

Theses, Dissertations and Capstones

The goal of this study is to examine the effect of urbanization and latitude on bone morphology, specifically limb length and bone density among gray squirrels endemic to the eastern United States. This study’s hypotheses are as follows: gray squirrels occupying lower latitudes will have larger body sizes and longer limbs relative to body size than those at higher latitudes following Bergmann’s and Allen’s rules. Further, squirrels in urban habitats will have greater bone density than those in rural habitats. Results show moderate correlation between body mass and respective proxies and latitude following Bergmann’s rule. Weak correlations were found between …

The Comparison Of Different Wetland Fish Assemblages Over Time, Robert Edward Adelstein

Theses, Dissertations and Capstones

Wetlands provide essential ecosystem services. Historically, we have drained and filled 73% of wetlands for agricultural use throughout the United States from the 1780s to the 1980s (Dahl, 1990). A nationwide focus on restoring wetlands has since occurred. Literature on restored/mitigated wetlands is rife with examples that do and do not support the same ecosystem services as natural wetlands (Langston, 1997; Meil, 2014). Restoration of wetlands occurred at the Green Bottom Wildlife Management Area (GBWMA) over several decades. Various sections of the wetland were classified by age, water depth, and vegetation. One hypothesis was that differences in fish assemblage would …

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 …

To Hum Or Not To Hum: Analyzing And Provoking Sound Production In The American Lobster (Homarus Americanus), Renske Kerkhofs

Honors Projects

American lobsters (Homarus americanus) produce humming sounds by vibrating their carapace. These sounds have a fundamental frequency on the order of 100 Hz, with multiple higher harmonics. Though I found no relationship between lobster carapace length and hum frequency, I observed sounds similarly structured to hums but with frequencies an order of magnitude higher, suggesting that lobsters may use a wider range of sounds than previously thought. Using laser vibrometry, I was able to pick up high frequencies of carapace vibration that were similar to those I observed on sound recordings. Lobsters seem to hum most readily when …

Restoration Is Repairing Relationships: Bridging Indigenous And Western Sciences To Assess The Socio-Ecological Restoration Of Wild Rice (Zizania Palustris) On Keweenaw Bay Indian Community Homelands, Cassandra M. Reed-Vandam

Dissertations, Master's Theses and Master's Reports

Manoomin (wild rice, Zizania palustris) is an ecologically and culturally significant plant relative for the Keweenaw Bay Indian Community (KBIC). Historically, manoomin was present across much of the Great Lakes, however, their presence has declined since the early 1900s and, by 1990, virtually disappeared within KBIC homelands. Employing ethnography, surveys, focus groups, and conversations with Ojibwa knowledge holders, this research defined successful manoomin restoration for KBIC and developed socio-ecological attributes and indicators to assess restoration presented in the Medicine Wheel Framework for Manoomin Restoration. Surface water, sediment, and pore water samples at six different manoomin sites were analyzed to …

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 …

Compliance And Roughness In Relation To Gecko Locomotion, Brooklynn Campbell

Williams Honors College, Honors Research Projects

Geckos move efficiently through a variety of substrates, from swaying branches to wooden fences to the sides of structures. Previous studies have studied locomotion and adhesion on manmade and rough substrates; however, the work is limited when discussing locomotion and adhesion as a relationship of compliance and roughness. Ease of movement was quantified by speed, under the assumption that the faster a gecko moves, the easier it is for the gecko to cross the substrate. Gehyra oceanica geckos from Moorea, French Polynesia were tested on substrates varying in compliance and roughness with four different treatments in total. Compliance, roughness, and …

A Conservation Model: Costa Rican Conservation Strategies Effectively Preserve Their Threatened Primates, Ryan Belmont

Regis University Student Publications (comprehensive collection)

The wildlife of Costa Rica has experienced various anthropogenic threats over the last century including climate change and agricultural expansion. The mantled howler monkey (Alloutta palliata), Central American spider monkey (Ateles geoffroyi), white-faced capuchin (Cebus imitator), and the Central American squirrel monkey (Saimiri oerstedii) are Costa Rica’s native primates that face several anthropogenic threats such as deforestation for agriculture and climate change. In response to increased threats to its four native species of non-human primates, Costa Rica has implemented effective governmental conservation tactics such as the Payments for Environmental Services program, ecotourism …

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …

Ms Environmental Biology Capstone Project, Sarah Luper

Regis University Student Publications (comprehensive collection)

Recreational trails and the presence of invasive species such as Bromus inermis can both disturb grassland community composition. Trails can act as dispersal corridors for plant material, but can also be a source of trampling and compaction. Invasive grasses like Bromus inermis can easily establish in grasslands and decrease species richness by increasing competition. Understanding these effects, this study aims to understand how both the presence of recreational trails as well as the presence of Bromus inermis affect species richness and overall community composition at Two Ponds National Wildlife Refuge. Belt transect sampling took place in fall 2019 and again …

Evaluación De La Producción De Humus En Eisenia Foetida (Lombriz Roja Californiana) Ante Fertilizantes Químicos Npk, Sergio Alberto Álvarez Cadena

Biología

El uso del lombricompost se ha convertido en una fuente de crecimiento relevante dentro del campo agrario, puesto que ha incursionado en la reducción del impacto ecológico de los fertilizantes químicos en gran variedad de cultivos. Sin embargo, el uso de este biofertilizante conlleva a un desarrollo poco eficiente de los cultivos en los primeros meses de aplicación, aspecto que genera menor productividad a corto plazo para los gremios agrarios, por lo que se ha mantenido el continuo uso de fertilizantes químicos que tienen efectos negativos en el ecosistema. Uno de los efectos es la contaminación del agua por lixiviación …

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 …

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 …

Quantifying The Ecological Effects Of Salix Fragilis On Riparian Habitat In Kittitas County, Washington, Landon Shaffer

All Master's Theses

Invasive species threaten plant community structure and function globally. Riparian areas, the zone near streams where water influences vegetation, are especially sensitive to invasive species colonization, suffering large-scale shifts in community composition. Salix fragilis (crack willow) is a nonnative riparian species abundant in the lower elevation tributaries of central Washington. Some speculate whether this willow should be listed as invasive in Washington, despite a lack of regional supporting evidence. I studied riparian communities dominated by either S. fragilis or native species in the Kittitas Valley and measured biodiversity, quantified differences in solar attenuation, and compared leaf decomposition rates to learn …