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Population Demographics Of Channel Catfish In The Lower Wabash River, Valerie J. Thompson Jan 2024

Population Demographics Of Channel Catfish In The Lower Wabash River, Valerie J. Thompson

Masters Theses

Inland fisheries are experiencing increasing demands due to anthropogenic stressors, especially within large river systems that support both recreational and commercial fisheries. Riverine species are sensitive to habitat degradation, species introductions, and exploitation, so continued monitoring and management of these communities are vital to maintain abundance and diversity within these systems. The North American catfish family, Ictaluridae, supports both recreational and commercial fisheries throughout the United States. Channel Catfish Ictalurus punctatus are heavily studied and managed compared to other sport catfishes in this family because of their economic and ecological significance. One important Channel Catfish fishery exists in the lower …


Molecular Investigation Of Tick-Borne Pathogens In Feral Swine (Sus Scrofa) From Seven Us States, Sofiane Aiche Jan 2024

Molecular Investigation Of Tick-Borne Pathogens In Feral Swine (Sus Scrofa) From Seven Us States, Sofiane Aiche

Masters Theses

Feral swine (Sus scrofa) have been proposed as part of the lifecycles of multiple tickborne pathogens (TBP). This is a result of the increase in feral swine populations and increased tick populations and geographic ranges. Few surveys exist on the TBP relevant to human and wildlife of feral swine in the US. The aim of this study is to investigate the prevalence of 10 TBP: Anaplasma spp., Borrelia spp., Cytauxzoon felis, Hepatozoon spp., Babesia spp., Mycoplasma spp., Trypanosoma cruzi, Toxoplasma gondii, Yersinia pestis, and Rickettsia spp. A total of 87 feral swine blood samples …


Exploring The Connection: Field Ecology Research And Student Wellbeing, Elizabeth Small Jan 2024

Exploring The Connection: Field Ecology Research And Student Wellbeing, Elizabeth Small

Graduate Research Theses & Dissertations

Field work is essential in ecological research, offering the opportunity to gather firsthand data, observe natural processes, and deepen our understanding of ecosystems. In my study on small mammal trophic niche dynamics, I investigate how small mammals—critical players in grassland food webs—adapt their diets in response to environmental disturbances. By examining the drivers of variation in trophic niche among three common small mammal species, I aim to uncover how these animals coexist despite similar dietary requirements. Understanding these dynamics is critical for informing global conservation efforts, especially as we work to reverse the biodiversity crisis and restore damaged ecosystems.However, the …


Alfred Russel Wallace Notes 29. Extraterrestrial Entertainment: Are We Being Monitored By Alien Beings?, Charles H. Smith Jan 2024

Alfred Russel Wallace Notes 29. Extraterrestrial Entertainment: Are We Being Monitored By Alien Beings?, Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (1823−1913) was an early advocate for the rational assessment of likelihood of extraterrestrial life. Current efforts to evaluate the situation have ranged from the heavily self-indulgent to the more objective, and it is still often difficult to decide just how much of the information we are receiving on the subject is dependable. An attempt is made here to cut through the haze and reduce the matter to elementals.


Moose Abundance And Calf:Cow Ratios On The Blackfeet Indian Reservation And Glacier National Park, Landon Joel Magee Jan 2024

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 …


Translocations Of North American Bison Across Large Climatic Gradients: Impacts On Thermoregulation, Body Size, And Helmintic Infection, Hayden Wolfe Jan 2024

Translocations Of North American Bison Across Large Climatic Gradients: Impacts On Thermoregulation, Body Size, And Helmintic Infection, Hayden Wolfe

Electronic Theses and Dissertations

Every year, one-eighth of all North American bison (Bison bison) are translocated, often across large climatic gradients. Over the last 16 years bison have been translocated from Wind Cave National Park in South Dakota to establish six herds across the United States central grasslands in Iowa, Missouri, Illinois, Indiana, and Kansas. Influence of climatic gradients on herd-level thermoregulation, body size, and helmintic infection were evaluated. Overall, 1174 thermal images and 1050 fecal samples were collected between 2021 and 2023. Physiological heat flux was used to measure thermoregulation, asymptotic body mass (ABM) was used for body size, and helminth genera abundance …


Improving Stream Connectivity In South Dakota, Colton Rainier Curtis Jan 2024

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 …


Better Understanding The Barred Owl, Adam Lee Potts Jan 2024

Better Understanding The Barred Owl, Adam Lee Potts

Graduate Student Theses, Dissertations, & Professional Papers

This thesis research presents an analysis of barred owl nest site selection in an understudied region of their expanded range. The barred owl has dramatically expanded its range westwards over the last 150 years, prompting multiple conflicting reinterpretations of their species account. Hypotheses of range expansion are reviewed to provide context for this study’s research. This study gathers empirical data on nest site selection in the mixed conifer forests of Montana’s Seeley-Swan and Mission Valleys. Eight barred owl nests were located following extensive territory surveys. Field measurements of tree height and diameter using USFS Forest Inventory and Analysis (FIA) plot …


Integrating Western Science And Indigenous Knowledge For Just Practices In Conservation, Cierra Lea Keith Jan 2024

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

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.


Fire Severity Mediates Marten And Fisher Occurrence: Impacts Of The Dixie Fire On A Carnivore Community, Christopher James Collier Jan 2024

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 …


Plasticity In Response To Temperature Magnitude And Variation---From Life History To Thermal Tolerance And Coloration, Austin Rex Hoffman Jan 2024

Plasticity In Response To Temperature Magnitude And Variation---From Life History To Thermal Tolerance And Coloration, Austin Rex Hoffman

University of the Pacific Theses and Dissertations

Warming associated with climate change has many direct and downstream effects on animals. For example, warmer developmental temperatures can improve heat tolerance and reduce insect melanization, which is related to coloration, thermoregulation, immunity, desiccation resistance, and potentially life-history traits, such as investment into reproduction and dispersal. Increased temperature variation is also a feature of climate change, and it may have a larger impact on animals than warming. However, I lack insight into the combined effects of temperature magnitude and variability on important traits of life history, thermal tolerance, and coloration. Thus, I integrated temperature variation into thermal performance using a …


Lycosidae Abundance And Diversity Across Lawn And Leaf Litter Substrate, Sage O. Lockett, Dan Albrecht-Mallinger Jan 2024

Lycosidae Abundance And Diversity Across Lawn And Leaf Litter Substrate, Sage O. Lockett, Dan Albrecht-Mallinger

UROP Posters

Significant knowledge gaps exist in how land-cover impacts ground-hunting spider populations. To fill these gaps, this study investigates a common family of ground-hunting spiders, Lycosidae, to determine differences in their abundance and diversity in deciduous leaf litter and managed turfgrass (lawn). The study was conducted within a forested ecosystem at Virginia Commonwealth University's Rice Rivers Center in Charles City County, Virginia. I placed 10 belt transects (1m x 20m) on lawn substrate and 10 identical transects in deciduous forest leaf litter substrate. I performed repeated visual census via eyeshine and manual capture of up to three individuals per transect …


Investigation Of L-Serine Synthesis And Transport As Stabilizing Feedback Mechanisms Within The Tsetse-Wigglesworthia Symbiosis, Ryan Phillips Jan 2024

Investigation Of L-Serine Synthesis And Transport As Stabilizing Feedback Mechanisms Within The Tsetse-Wigglesworthia Symbiosis, Ryan Phillips

Graduate Theses, Dissertations, and Problem Reports (ETD)

Tsetse flies (Glossina morsitans), which are the obligate vectors of Old-World trypanosomes (Trypanosoma spp.) that cause African trypanosomiasis, have a bacteriome that houses the intracellular endosymbiont Wigglesworthia glossinidia. The ancient coevolution of these species has led to the integration of Wigglesworthia metabolism into tsetse physiology and a subsequent reliance on nutrient exchange for maintaining the fitness of both partners. The establishment of this obligate mutualism has facilitated the emergence of feedback mechanisms that stabilize the symbiosis, such as that which involves the exchange of L-serine and B vitamins. The Gammaproteobacteria Wigglesworthia supplement B vitamins lacking …


Long- And Short-Term Weather Variables Affect Capture Rates In Western Painted Turtles (Chrysemys Picta Bellii) In Marshall Co., South Dakota, Amy Dolan, Heather L. Waye, Peter Dolan Jan 2024

Long- And Short-Term Weather Variables Affect Capture Rates In Western Painted Turtles (Chrysemys Picta Bellii) In Marshall Co., South Dakota, Amy Dolan, Heather L. Waye, Peter Dolan

Biology Publications

Turtle populations are declining globally, and yet accurate long-term population surveys are often lacking. Even amongst widespread species, information on long-term population trends is largely missing. As such, studies on demographics, population structure, and factors that affect capture efficacy are needed. In 2019 we began a long-term study on Western Painted Turtles (Chrysemys picta bellii) in the Couteau des Prairie habitat in northeastern South Dakota. We captured turtles using several trapping techniques and investigated the effects of short- and long-term weather variables on catch per unit effort. Temperature was positively associated with daily capture rates, showing the strongest …


Automatic Detection Of Birds In Images Acquired With Remotely Piloted Aircraft For Managing Wildlife Strikes To Civil Aircraft, Maurycio Rodrigues Oviedo, Flavio A. C. Mendonca Ph.D., Jose Cabrera, Cole A. Mcnall, Raymond Ayres, Ricardo Luís Barbosa, Rodrigo Gallis Jan 2024

Automatic Detection Of Birds In Images Acquired With Remotely Piloted Aircraft For Managing Wildlife Strikes To Civil Aircraft, Maurycio Rodrigues Oviedo, Flavio A. C. Mendonca Ph.D., Jose Cabrera, Cole A. Mcnall, Raymond Ayres, Ricardo Luís Barbosa, Rodrigo Gallis

International Journal of Aviation, Aeronautics, and Aerospace

Wildlife strikes represent a significant threat to aviation safety and economics, as evidenced by notable incidents such as the emergency landing of US Airways Flight 1549 in 2009. The Federal Aviation Administration (FAA) acknowledges this growing concern, as evidenced by its report on Wildlife Strikes to Civil Aircraft in the United States from 1990 to 2019.To address the need for improved risk management, airports conduct Wildlife Hazard Assessments (WHA), a laborious process typically relying on visual identification by Qualified Airport Wildlife Biologists (QAWB). However, technological advancements, such as Remotely Piloted Aircraft (RPA) and machine learning (ML), offer promising solutions to …


A Case Of Incipient Budding Speciation In The California Floristic Province, Infraspecific Divergence In Abronia Villosa, Eli J. Allen Jan 2024

A Case Of Incipient Budding Speciation In The California Floristic Province, Infraspecific Divergence In Abronia Villosa, Eli J. Allen

Cal Poly Humboldt theses and projects

Physical barriers to gene flow are the traditional evidence for species divergence. Conversely, there has been increasing acknowledgment of speciation in the face of gene flow as an evolutionary process. Budding speciation involves peripheral populations adapting to local ecological conditions, thereby budding off from a widespread progenitor species. Budding speciation is distinguished by ecological divergence and is generally evidenced by asymmetrical range size and nested phylogenetic relationships of sister species. The narrow endemic Abronia villosa var. aurita is adapted to montane sandy washes adjacent to its widespread sister variety, the desert dwelling var. villosa. Here, I tested the hypothesis …


The Nature And Extent Of Algal Symbiosis In Three North American Ranids, Zachary T. Vegso Jan 2024

The Nature And Extent Of Algal Symbiosis In Three North American Ranids, Zachary T. Vegso

Cal Poly Humboldt theses and projects

The symbiotic relationship between the chlamydomonad green alga Oophila amblystomatis and embryos of certain amphibian species is often presumed to be mutualistic. However, the existence of a mutualism has only been experimentally tested and established in two closely related ambystomatid salamanders. These experiments showed a positive correlation between intracapsular algal density and embryonic growth, survival, hatching synchrony, and hatchling body size. Oophila has been documented within egg capsules of a growing number of amphibian species, including several frogs in the family Ranidae. However, the nature and extent of this relationship remains unclear. Ranid eggs are better oxygenated than ambystomatid eggs, …


Effects Of Habitat Selection And Individual Quality On The Reproductive Success Of Barn Owls (Tyto Furcata), Jaime E. Carlino Jan 2024

Effects Of Habitat Selection And Individual Quality On The Reproductive Success Of Barn Owls (Tyto Furcata), Jaime E. Carlino

Cal Poly Humboldt theses and projects

The hypothesis of adaptive breeding habitat selection proposes congruence between the evolved selection of habitats and fitness components such as reproductive success. However, mismatches between habitat selection and observed fitness outcomes are not unusual and can arise for multiple reasons. Variation in individual qualities of animals has also been found to affect reproduction and survival. I examined associations between barn owl nest box selection, reproductive output, and plumage characteristics previously shown to correspond to individual quality. I found that barn owls selected tall nest boxes made of wood, mounted high off the ground, and with increased proportions of grassland around …


The Effects Of Native Perennial Cover On Physiological Indicators Of Habitat Quality For Sparrows In California Coastal Prairie Rangelands, Madeleine A. Ybarra Jan 2024

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 …


Using Novel And Traditional Survey Techniques To Monitor Small Mammal Species In Northwestern California, Sydney Mccluskey Jan 2024

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) …


Scale And Habitat Effects On Measurement Of Streptomyces Biogeography And Biodiversity, Terilyn A. Stoflet Jan 2024

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 Jan 2024

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 …


Interactions Between New Zealand Mud Snails (Potamopyrgus Antipodarum) And Toxic Cyanoabacteria (Anabaena) In Baduwa’T (Mad River), Humboldt County, California, Cecilia F. Kennelly Jan 2024

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 The Drivers Of Nocturnal Behavior Of Pikas At Lower Elevations In Lassen National Forest, California, Evan Burnett Jan 2024

Examining The Drivers Of Nocturnal Behavior Of Pikas At Lower Elevations In Lassen National Forest, California, Evan Burnett

Cal Poly Humboldt theses and projects

The American pika (Ochotona princeps) is a charismatic mammal species adapted to occupy rockslides and boulder fields in western North America. Historically monitored due to their climate sensitivity, pikas have experienced extirpations along their lower range margins—driven by chronic and acute temperature stress—prompting increased concern and monitoring over the risks posed by anthropogenic climate change. Traditionally considered an alpine species, pikas occupy a wide range of elevations, with those at lower elevations exhibiting higher rates of nocturnality than their counterparts at higher elevations. Temperature is hypothesized to be the driver, but this has yet to be confirmed. Pikas …


The Spatial Ecology Of Plains Spotted Skunks In South Dakota: Insights From Species Distribution, Resource Selection, And Co-Occurrence Models, Kara M. White Jan 2024

The Spatial Ecology Of Plains Spotted Skunks In South Dakota: Insights From Species Distribution, Resource Selection, And Co-Occurrence Models, Kara M. White

Electronic Theses and Dissertations

The plains spotted skunk (Spilogale interrupta) is a data-deficient small carnivore native to the central plains of North America that has experienced significant population declines. My dissertation investigates the species’ distribution, habitat associations, and interspecific interactions in South Dakota, providing crucial information for conservation actions. In Chapter 1, I developed ensemble distribution models on a broad scale, incorporating species location data from 1985–2020, environmental factors, and six predictive modeling algorithms. I identified key predictors including mean temperature diurnal range and proportion of area as pasture, and estimated ~31,300 km2 of potential habitat, predominately in eastern South Dakota. In Chapter 2, …


Methods For Optimizing Detection And Evaluating Habitat Use Of North American River Otters In South Dakota, Jessica Speiser Jan 2024

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 …


The Sources And Fates Of Nutrients In The Deep Lake Watershed, Kiler Austin Kenison Jan 2024

The Sources And Fates Of Nutrients In The Deep Lake Watershed, Kiler Austin Kenison

EWU Masters Thesis Collection

This water quality survey determined the sources and fates of nutrients within the Deep Lake watershed located in Stevens County, WA. Deep Lake is a 191-acre exorheic lake found just below the Canadian border in northeast Washington state. It is situated at the bottom of a narrow valley with steep walls and is fed throughout the year by snowmelt from tributaries descending the mountains surrounding it. Above and to the north of the lake, the tributaries are utilized by cattle ranchers as a water source for livestock while a small community of homes surrounds the lake. Water samples, discharge, and …


Exploring Long-Term Patterns: Black Bass Tournament Fishery And Population Trends In West Virginia's Navigable Rivers, Alex J. Benecke Jan 2024

Exploring Long-Term Patterns: Black Bass Tournament Fishery And Population Trends In West Virginia's Navigable Rivers, Alex J. Benecke

Graduate Theses, Dissertations, and Problem Reports (ETD)

Black bass Micropterus spp. are popular sport fish in West Virginia’s navigable rivers. In recent years, anglers have expressed concerns about a potential decline in fishery quality. To investigate these claims, we evaluated whether fishery quality has declined compared to earlier periods and whether population trends correspond to angler catch rates. Specifically, we aimed to (1) examine changes in species catch over time and during key periods, such as tournament and spawning seasons; (2) describe the distribution of black bass species across pools and habitat types; and (3) assess the outcomes of previous stocking efforts. To address these objectives, we …


Effects Of Land Cover Changes And Hydropower Development On Fish Communities In Amazonian Floodplain Rivers, Samuel Baron Grinstead Hessburg Jan 2024

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 (ETD)

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 …


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 Jan 2024

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 …