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Effects Of Anthropogenic Noise On The Provisioning Behavior Of Western Bluebirds And Artificial Light At Night On Nestling Development, Kerstin H. Ozkan Mar 2024

Effects Of Anthropogenic Noise On The Provisioning Behavior Of Western Bluebirds And Artificial Light At Night On Nestling Development, Kerstin H. Ozkan

Master's Theses

Sensory environments are rapidly changing due to increased human activity in urban and non-urban areas alike. For instance, background sounds can interfere with parent-offspring communication and mask cues reflective of predation risk, resulting in elevated vigilance at the cost of provisioning. In chapter 1, we studied nestling provisioning behavior among Western Bluebirds (Sialia mexicana) in response to short-term (1 hr) and long-term (continuous exposure throughout nesting period) noise exposure. Provisioning rates were lower at nests exposed to short-term experimental traffic noise compared to exposure to ambient background sounds. Trial order strongly influenced provisioning behavior, with the decline in …


A Review Of Undrowned: Black Feminist Lessons From Marine Mammals, Nadia G. Dresscher-Lambertus Jun 2023

A Review Of Undrowned: Black Feminist Lessons From Marine Mammals, Nadia G. Dresscher-Lambertus

Feminist Pedagogy

No abstract provided.


Hydric Physiology Of Lizards, Savannah Weaver Jun 2023

Hydric Physiology Of Lizards, Savannah Weaver

Master's Theses

Chapter 1: Animals can respond to extreme climate by behaviorally avoiding it, or by physiologically coping with it. We understand behavioral thermoregulation and physiological thermal tolerances, but water balance has largely been neglected. Climate change includes both global warming and changes in precipitation regimes, so improving our understanding of organismal water balance is increasingly urgent. We assessed the hydric physiology of endangered Blunt-nosed Leopard Lizards (Gambelia sila) by measuring cutaneous evaporative water loss (CEWL), plasma osmolality, body mass, and body condition throughout their active season. On average, G. sila had low CEWL that is likely desert-adaptive, and high …


Lichens Of Ultramafic Rocks: A Multidisciplinary Approach To Understanding The Ecology Of An Understudied Organism In A Well-Studied System, Michael Mulroy Mar 2023

Lichens Of Ultramafic Rocks: A Multidisciplinary Approach To Understanding The Ecology Of An Understudied Organism In A Well-Studied System, Michael Mulroy

Master's Theses

Lichens are among the most prominent and successful life forms of metal-rich habitats, including ultramafic rocks and soils; however, research on lichens of ultramafic habitats is limited, especially on the North American continent. A review of the published literature on lichens of ultramafic substrates in North America yielded a total of 437 lichen species reported from ultramafic rocks and soils. Lichen assemblages of ultramafic substrates vary in composition and are dominated by acidophytic (low pH preferring) taxa with a minor, but consistent, basiphytic (high pH preferring) component. Species lists from ultramafic habitats in different geographic regions varied widely, suggesting that …


Ectotherm Thermoregulation At Fine Scales: Novel Methods Reveal A Link Between The Spatial Distribution Of Temperature And Habitat Quality, Ian Axsom Dec 2022

Ectotherm Thermoregulation At Fine Scales: Novel Methods Reveal A Link Between The Spatial Distribution Of Temperature And Habitat Quality, Ian Axsom

Master's Theses

Investigating ecological questions at the scale of individual organisms is necessary to understand and predict the biological consequences of environmental conditions. For small organisms this can be challenging because we need tools with the appropriate accuracy and resolution to record and quantify their ecological interactions. Unfortunately, many of our existing tools are only appropriate for medium to large organisms or those that are wide ranging, inhibiting our ability to investigate the ecology of small organisms at fine scales.

In Chapter 1, I tested a novel workflow for recording animal movements at very fine spatial and temporal scales. The workflow combined …


Understanding Rare Species In California: An Assessment Of Camatta Canyon Amole (Hooveria Purpurea Var. Reducta) And A Meta-Analysis Of California Rare Plants In Literature, Kieran N. Althaus Jun 2022

Understanding Rare Species In California: An Assessment Of Camatta Canyon Amole (Hooveria Purpurea Var. Reducta) And A Meta-Analysis Of California Rare Plants In Literature, Kieran N. Althaus

Master's Theses

California is currently in the midst of a biodiversity crisis. There are approximately 5,000 native species of plants in California, a quarter of which are considered rare. Determining threats to these rare plants is often times difficult. Despite California's botanical resources, we still know very little about much of California’s rare plants. San Luis Obispo County is home to 2,000 of California’s native plant taxa, one- third of which are rare or endemic to the county. These species are of great local and environmental concern.

In Chapter 1, we attempted to assess the impact of non native species on a …


Distribution And Ecological Function Of Pacific Lamprey In The San Luis Obispo Creek Watershed, Parker Kalan Jun 2022

Distribution And Ecological Function Of Pacific Lamprey In The San Luis Obispo Creek Watershed, Parker Kalan

Master's Theses

Pacific lamprey (Entosphenus tridentatus) is an endemic species to coastal watersheds along the Pacific Rim in North America and Asia. The species' geographic distribution is retracting and has not been mapped precisely, and the ability for the species to provide ecosystem services, such as water filtration, for supporting watershed management has not been tested. The San Luis Obispo Creek watershed, California, USA is at the southern end of Pacific lamprey’s retracting distribution, and the San Luis Obispo watershed is impacted by degraded water quality, making investigation of Pacific lamprey in the San Luis Obispo Creek watershed of direct …


Analysis Of The Slo Bay Microbiome From A Network Perspective, Lien Viet Nguyen Jul 2021

Analysis Of The Slo Bay Microbiome From A Network Perspective, Lien Viet Nguyen

Master's Theses

Microorganisms are key players in the ecosystem functioning. In this thesis, we developed a framework to preprocess raw microbiome data, build a correlation network, and analyze co-occurrence patterns between microbes. We then applied this framework to a marine microbiome dataset. The dataset used in this study comes from a year-long time-series to characterize the microbial communities in our coastal waters off the Cal Poly Pier. In analyzing this dataset, we were able to observe and confirm previously discovered patterns of interactions and generate hypotheses about new patterns. The analysis of co-occurrences between prokaryotic and eukaryotic taxa is relatively novel and …


Not So Dystopian: A Historical Reading Of Eugenics In Science Fiction, Riley Sanders Jun 2021

Not So Dystopian: A Historical Reading Of Eugenics In Science Fiction, Riley Sanders

The Forum: Journal of History

Broadly, this paper is an effort in complicating traditional readings of eugenic themes in science fiction. Two landmark novels, Wells’ The Island of Dr. Moreau (1896) and Huxley’s Brave New World (1932), are highlighted as representative of the early and late stages of eugenics. By focusing on the troubling historical context surrounding these authors, I denounce the simple reading of these works as merely “dystopian”. Scholars like Francis Fukuyama advance these simplistic readings by instinctively assuming that Wells and Huxley were against eugenics. This paper continues the tradition that David Bradshaw popularized in his book The Hidden Huxley, which argues …


Assessing Cryptic Dispersal And Movement In The Lompoc Kangaroo Rat, Katherine A. Belnick Jun 2021

Assessing Cryptic Dispersal And Movement In The Lompoc Kangaroo Rat, Katherine A. Belnick

Biological Sciences

Lompoc kangaroo rats (LKR, Dipodomys heermanni arenae) are small rodents that reside in sand dunes from Pismo to Orcutt, including the Oceano Dunes State Vehicular Recreation Area (SVRA), in Oceano, CA. In the SVRA, some of these individuals live in habitat islands, which are habitat fragments of dense vegetation disrupted by empty, bare sand in between them. Recreational vehicle activity is permitted in the Oceano Dunes, which has caused persistence habitat fragmentation. Kangaroo rats are known to disperse between habitat islands and are suspected to do so via a special type of dispersal: cryptic dispersal. This dispersal mode, if it …


Rapid Warming Events In A Small Coastal Upwelling Embayment, Tatjana E. Ellis Jun 2021

Rapid Warming Events In A Small Coastal Upwelling Embayment, Tatjana E. Ellis

Physics

Temperature variability in the nearshore coastal ocean influences various biological processes and can drive changes in biodiversity and habitat range. Despite recent progress, there are still significant gaps in the understanding of drivers of temperature variability in upwelling bays, particularly at higher frequencies. In this study, we analyzed a decade of nearshore temperature measurements both inside and outside a small coastal embayment located in central California [San Luis Obispo (SLO) bay], as well as temperature data from satellites, to characterize rapid warming events. We found that rapid warming events, defined using rates of temperature change across different thresholds, occurred more …


Habitat Heterogeneity Affects The Thermal Ecology Of The Federally Endangered Blunt-Nosed Leopard Lizard, Nicole Gaudenti Jun 2021

Habitat Heterogeneity Affects The Thermal Ecology Of The Federally Endangered Blunt-Nosed Leopard Lizard, Nicole Gaudenti

Master's Theses

Global climate change is already contributing to the extirpation of numerous species worldwide, and sensitive species will continue to face challenges associated with rising temperatures throughout this century and beyond. It is especially important to evaluate the thermal ecology of endangered ectotherm species now so that mitigation measures can be taken as early as possible. A recent study of the thermal ecology of the federally endangered Blunt-Nosed Leopard Lizard (Gambelia sila) suggested that they face major activity restrictions due to thermal constraints in their desert habitat, but that large shade-providing shrubs act as thermal buffers to allow them …


Selection Of Overwintering Microclimate By Migratory Western Monarch Butterflies, Kiana Saniee Jun 2021

Selection Of Overwintering Microclimate By Migratory Western Monarch Butterflies, Kiana Saniee

Master's Theses

Migratory species are expected to demonstrate habitat selection that occurs at multiple spatial and temporal scales. Western monarch butterflies migrate seasonally to overwinter in groves at geographically predictable locations along the California coast. To date, overwintering habitat selection by western monarch butterflies has been studied assuming that habitat selection occurs where overwintering aggregations form, meaning at the spatial scale where monarchs form dense overwintering aggregations within overwintering groves. We argue that since western monarch butterflies are migratory, studies of habitat selection could have commingled selection at different scales into a single spatial scale. This likely leads to ignoring some levels …


Reciprocal Transplant And Machine Learning Study Of Oak Mistletoe On Three Host Oak Species In Santa Margarita, California, Ella Abelli-Amen Jun 2021

Reciprocal Transplant And Machine Learning Study Of Oak Mistletoe On Three Host Oak Species In Santa Margarita, California, Ella Abelli-Amen

Master's Theses

At Santa Margarita Ranch, California, oak mistletoe (Phoradendron villosum) parasitizes valley oak and blue oak but cannot be found growing on coast live oak despite its abundance and ability to parasitize coast live oak in other areas. It seems as though this species of mistletoe is specializing on certain host oak trees, but the mechanisms of this specialization are unknown. In order to investigate this pattern, we utilized a type of machine learning in GIS called supervised classification as well as a reciprocal transplant study in the field. The three species of oak trees were classified with 87% accuracy using …


Natural And Experimental Noise Affects Acoustic Communication In Songbirds, Veronica Arlene Reed Mar 2021

Natural And Experimental Noise Affects Acoustic Communication In Songbirds, Veronica Arlene Reed

Master's Theses

Background noise is ubiquitous and can impair acoustic communication and influence signaling behavior in animals. Despite evidence demonstrating myriad effects of anthropogenic noise on animal communication, precisely how natural background noise influences communication and behavior remains unclear. Yet, natural sources of background noise, such as rushing rivers or crashing ocean surf, share similar power spectra to sources of anthropogenic noise and can occur at high amplitudes, potentially masking acoustic signals.

To investigate the effects of water-generated noise on songbird behavior, we experimentally broadcast landscape-level playbacks of ocean surf and river noise in coastal California, USA, and riparian habitat in Idaho, …


Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams Sep 2020

Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams

Master's Theses

Planktonic larvae of marine organisms are increasingly being exposed and required to respond to a changing physical environment. Adult sea urchins occupy both intertidal and subtidal waters and broadcast spawn gametes into the water column to contend with variable physical conditions. To answer how populations of invertebrates residing at different depths adequately prepare their offspring to cope with different levels of ultraviolet radiation (UVR), we collected adult purple sea urchins, Strongylocentrotus purpuratus, from four sites (two intertidal and two subtidal (~15 m deep)) on the central coast of CA to compare UV tolerance in offspring. Our measurements of UVA …


The Influence Of The Sensory Environment On Avian Reproductive Success And Human Well-Being, Danielle Marie Ferraro Jun 2020

The Influence Of The Sensory Environment On Avian Reproductive Success And Human Well-Being, Danielle Marie Ferraro

Master's Theses

Sensory pollutants such as anthropogenic noise and night lighting now expose much of the world to evolutionarily novel sound and night lighting conditions, which can have detrimental effects on humans and wildlife. In my first chapter, we exposed wild Western Bluebird (Sialia mexicana) nestlings to noise, light, and combination (i.e., noise and light) treatments. Nests exposed to noise and light together experienced less predation than control and light-exposed nests, and noise-exposed nests experienced less predation than control nests, yet overall nest success was only higher in noise-exposed nests compared to light-exposed nests. Although exposure to light decreased nestling body condition …


Pismo Clams (Tivela Stultorum) In Califorina: Population Status, Habitat Associations, Reproduction, And Growth, Alexandria R. Marquardt May 2020

Pismo Clams (Tivela Stultorum) In Califorina: Population Status, Habitat Associations, Reproduction, And Growth, Alexandria R. Marquardt

Master's Theses

Marine shellfish play a vital role in intertidal ecosystems and coastal communities, but many of these fisheries are small-scale and lack the necessary monitoring to ensure long-term sustainability. Effective management often requires information on key demographic parameters, such as population status, reproduction and growth. Pismo clams (Tivela stultorum) are a culturally important and iconic species in California, which supported a thriving commercial and recreational fishery throughout much of the 1900’s. However, Pismo clam populations have declined statewide in recent decades and are attributed to human harvest and predation by California sea otters (Enhydra lutris); However, no …


Fucus Distichus: Investigating Humidity And Temperature Between Tides, Jason Thomas, Andrew Chang, Julia Blum, Chela Zabin Aug 2019

Fucus Distichus: Investigating Humidity And Temperature Between Tides, Jason Thomas, Andrew Chang, Julia Blum, Chela Zabin

STAR Program Research Presentations

Environmental elements such as changing rapidly changing temperature, prolonged periods of low to no water exposure, desiccation, predation and increased wave action can influence the diversity of microhabitats that inhabit the littoral zones. When making observations of various shorelines, specifically the physical conditions of the surrounding marine vegetation (i.e. Fucus distichus), an inquiry is made as to the role of Fucus in the amelioration of stressors on the marine habitat during low tide (MLLW), however, due to time considerations, temperature and humidity are the focus of this study. Using temperature and humidity probes, monitoring data shows that Fucus provides …


Abundance And Community Composition Of Invasive Intertidal Watersipora On The San Francisco Bay Area Outer Coast, Kevin Myron, Meredtyh Duncan, Jaden Stone, C. Sarah Cohen Aug 2019

Abundance And Community Composition Of Invasive Intertidal Watersipora On The San Francisco Bay Area Outer Coast, Kevin Myron, Meredtyh Duncan, Jaden Stone, C. Sarah Cohen

STAR Program Research Presentations

Invasive species can lead to serious ecological changes. The San Francisco Bay area is one of the most invaded areas in the world due to the commercial shipping industry and recreational water vessels. While the intertidal is not widely invaded, the harbors and docks are. One exception to this is the invasive, colonial filter-feeding bryozoan Watersipora, which has been found at various rocky outer coast sites. Further investigation into how the sites are invaded by this organism and their impact on native species must be carried out. In this project, at four intertidal sites around the SF Bay outflow, we …


Infestation Intensities, Attachment Patterns, And The Effect On Host Contest Behavior Of The Tick Ixodes Pacificus On The Lizard Sceloporus Occidentalis, Dylan M. Lanser Aug 2019

Infestation Intensities, Attachment Patterns, And The Effect On Host Contest Behavior Of The Tick Ixodes Pacificus On The Lizard Sceloporus Occidentalis, Dylan M. Lanser

Master's Theses

Parasites often have profound effects on the survival and evolution of their hosts, and hence on the structure and health of entire ecosystems. Yet basic questions, such as the degree of virulence of a given parasite on its host, and factors influencing which hosts in a population are at the greatest risk of infection, are vexingly difficult to resolve. The western blacklegged tick-western fence lizard (Ixodes pacificus-Sceloporus occidentalis) system is important, primarily because I. pacificus, a vector of the Lyme disease spirochete Borrelia burgdorferi, is dependent on S. occidentalis for blood meals in its subadult stages, …


Short Term Shifts In Soil Nematode Food Feb Structure And Nutrient Cycling Following Sustainable Soil Management In A California Vineyard, Holly M. Deniston-Sheets Jul 2019

Short Term Shifts In Soil Nematode Food Feb Structure And Nutrient Cycling Following Sustainable Soil Management In A California Vineyard, Holly M. Deniston-Sheets

Master's Theses

Evaluating soil health using bioindicator organisms has been suggested as a method of analyzing the long-term sustainability of agricultural management practices. The main objective of this study was to determine the effects of vineyard management strategies on soil food web structure and function, using nematodes as bioindicators by calculating established nematode ecological indices. Three field trials were conducted in a commercial Pinot Noir vineyard in San Luis Obispo, California; the effects of (i) fertilizer type (organic and inorganic), (ii) weed management (herbicide and tillage), and (iii) cover crops (high or low water requirements) on nematode community structure, soil nutrient content, …


Rescue And Rehabilitation Of A Juvenile Red-Tailed Hawk: A Case Study, Maya Higa Jun 2019

Rescue And Rehabilitation Of A Juvenile Red-Tailed Hawk: A Case Study, Maya Higa

Agricultural Education and Communication

Many raptor species are becoming threatened and, in some cases, endangered as a result of human activity including habitat destruction and pesticide use (Morishita, Fullerton, Lowenstine, Gardner & Brooks, 1998). Because of this, raptor rehabilitation has become increasingly popular in conservation efforts. In North America, the red-tailed hawk is one of the most widespread and commonly known birds of prey (Preston & Beane, 2009). According to the National Audubon Society, the conservation status of red-tailed hawks is currently of least concern and numbers may even be increasing in some areas since the 1960s. While this species is not threatened, the …


Dna And Protein Sequence Analysis Of Neuronal Markers Neuronal Nuclei (Neun) And Doublecortin (Dcx) In The Northern Pacific Rattlesnake (Crotalus Oreganus) And Western Fence Lizard (Sceloporus Occidentalis)., Brett M. Vassar Jun 2019

Dna And Protein Sequence Analysis Of Neuronal Markers Neuronal Nuclei (Neun) And Doublecortin (Dcx) In The Northern Pacific Rattlesnake (Crotalus Oreganus) And Western Fence Lizard (Sceloporus Occidentalis)., Brett M. Vassar

Master's Theses

Neuronal Nuclei (NeuN) and Doublecortin (DCX) are neuron specific proteins that are used in histological studies of brain structure in a variety of vertebrate taxa.Antibodies against NeuN (anti-NeuN) bind to the Fox-3 protein, an RNA binding protein common in mature neurons. Anti-DCX labels a microtubule-associated protein expressed in actively dividing neural progenitor cells and migrating neurons. The DCX gene encodes a protein that is well conserved across mammalian, avian, and a few reptilian species, therefore anti-DCX staining has been used successfully across a range of vertebrate taxa. Successful neuronal staining using anti-NeuN has been demonstrated in mammals, birds, and the …


Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell May 2019

Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell

Master's Theses

Global biodiversity is declining as a direct result of anthropogenic climate change. Ectothermic species have become focal organisms for studying the ecological effects of altered climates due to the clear relationship between environmental temperatures and ectotherms’ basic physiological functions. Historically, examinations of these effects have focused heavily on heliothermic lizards, and most others have tended to focus on single populations or sympatric species within a single community. Addressing the longterm energetic implications of environmental temperature variation will provide valuable insight into the cascading physiological effects that certain populations or species may experience as a result of altered climates.

In this …


Cichlid Size Vs Flow Rate, Amy E. Naumovski Jan 2019

Cichlid Size Vs Flow Rate, Amy E. Naumovski

STAR Program Research Presentations

Cichlids are a diverse group of fish that are known for their prenatal and postnatal care of their eggs and frys (baby fish). This unique characteristic creates a limitation on the amount of eggs a cichlid can lay and protect, which is particulalry effected by the size of the eggs. Cichlids have a large variance in their egg size, which correlates to a large variance in their fry size. This project explores the trade offs cichlids make in egg size and fry size by specifically testing the ability of varying sized cichlids to swim in different flow rates. This could …


Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen Jan 2019

Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen

STAR Program Research Presentations

Leptasterias spp. is a species complex of small, six rayed, predatory sea stars that inhabit rocky intertidal communities along the Pacific coast of North America. A developmental mode of brooding their young, rather than broadcasting for planktonic development, limits dispersal away from the natal area, and may also result in fine scale local adaptation of populations. Local adaptation may lead to morphological and behavioral differences among populations, specifically towards the most available prey. Within the rocky intertidalthere are zones of high and low wave impact which create microhabitats with their own selective forces. In areas of high wave impact, stars …


The Thermal Ecology Of Sceloporus Occidentalis, Luis Patricio Burgos Dec 2018

The Thermal Ecology Of Sceloporus Occidentalis, Luis Patricio Burgos

Master's Theses

With temperatures rising globally, assessing the possible impacts of the changing climate becomes more and more urgent. Ectotherms are excellent indicators of potential climatic ramifications on biodiversity because of their heavy reliance on the environment for their thermoregulation. Studies have historically looked at thermal tolerance values to establish predictive models for population and species extinctions.

In chapter 1, we looked at recent studies that suggest that thermal tolerance may be a plastic trait and test the effects empirically. Most studies are based on captive lizards acclimated to laboratory conditions that do not necessarily reflect natural environments, and if thermal tolerance …


Comparison Of An Endangered Species’ Seed Bank Before And After Ungulate Removal, Melanie K. Phillips, Kathryn Mceachern Sep 2018

Comparison Of An Endangered Species’ Seed Bank Before And After Ungulate Removal, Melanie K. Phillips, Kathryn Mceachern

STAR Program Research Presentations

The purpose of this study was to assess the impact of the removal of ungulates on the soil seed bank of the endemic Santa Rosa Island manzanita (Arctostaphylos confertiflora). A. confertiflora was trampled and browsed by non-native ungulates between the years 1850 and 2011 which reduced its ability to produce seeds.This species is an obligate seeder, meaning that sprouting from seeds in the soil is its only method of reproduction. Due in part to the lack of its soil seed bank, this species was federally listed as endangered by the US Fish and Wildlife Service in 1997. In order to …


Crossing Corridors: Wildlife Use Of Jumpouts And Undercrossings Along A Highway With Wildlife Exclusion Fencing, Alex J. Jensen Aug 2018

Crossing Corridors: Wildlife Use Of Jumpouts And Undercrossings Along A Highway With Wildlife Exclusion Fencing, Alex J. Jensen

Master's Theses

Roads pose two central problems for wildlife: wildlife-vehicle collisions (WVCs) and habitat fragmentation. Wildlife exclusion fencing can reduce WVCs but can exacerbate fragmentation. In Chapter 1, I summarize the relevant studies addressing these two problems, with a focus on large mammals in North America. Chapters 2 and 3 summarize field assessments of technologies to reduce WVCs and maintain connectivity, specifically jumpout ramps and underpasses, along Highway 101 near San Luis Obispo, CA. In a fenced highway, some animals inevitably breach the fence and become trapped, which increases the risk of a wildlife-vehicle collision. Earthen escape ramps, or “jumpouts”, can allow …