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Diets Of Double-Crested Cormorants In The Lake Winnebago System, Wisconsin, Ryan P. Koenigs, Daniel J. Dembkowski, Charles D. Lovell, Daniel A. Isermann, Adam D. Nickel

United States Department of Agriculture Wildlife Services: Staff Publications

Double-crested cormorant Phalacrocorox auritus Lesson (cormorant) populations have increased throughout the Great Lakes region of North America causing concern related to the impact of cormorant predation on fish communities. A recent decline in yellow perch Perca flavescens (Mitchill) abundance within the Lake Winnebago System, Wisconsin, USA, prompted an assessment of cormorant diets to evaluate potential effects of cormorant predation on the sportfish community. Diets were collected from 883 cormorants (417 from Lake Winnebago and 466 from Lake Butte des Morts) between 2015 and 2017. Cormorant diets on both waterbodies consisted mostly of freshwater drum Aplodinotus grunniens Rafinesque and gizzard shad …

Evaluation Of A Warfarin Bait For Controlling Invasive Wild Pigs (Sus Scrofa), James C. Beasley, Lindsay M. Clontz, Allison Rakowski, Nathan P. Snow, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

BACKGROUND: Wild pigs (Sus scrofa) cause widespread environmental and economic damage, and as a result are subjected to extensive control. Current management strategies have proven insufficient, and there is growing interest in use of toxicants to control invasive populations of this species. In 2017 a low-dose warfarin bait was federally approved for use in controlling wild pigs in the United States. However, no states have allowed use of this bait due to unanswered questions regarding welfare concerns, field efficacy, and non-target impacts.

RESULTS: All captive wild pigs fed 0.005% warfarin baits in no choice feeding trials succumbed in an average …

Preclassic Cultural Eutrophication Of Lake Petén Itzá, Lowland Guatemala, By The Early Maya Of Nixtun-Ch'ich', Brooke A. Birkett

Masters Theses

"Paleolimnological evidence indicates the ancient Maya transformed lowland terrestrial ecosystems by felling forest vegetation to construct large civic-ceremonial centers and expand agriculture. The effects of prehistoric Maya land alterations on lake trophic status, however, remain poorly understood. We analyzed a 515-cm-long sediment core from Lake Petén Itzá, lowland Guatemala, to infer paleoenvironmental changes resulting from Maya occupation of the riparian archaeological site of Nixtun-Ch'ich'. Substantial increases in charcoal and fecal stanol concentrations indicate Maya occupation of the Candelaria Peninsula by the late Early Preclassic period beginning ca. 1400 cal yr Before the Common Era (hereafter BCE), despite scant archaeological evidence …

Effects Of Salt Runoff On Aquatic Macroinvertebrate Colonies, Kendra Fink

Journal of Earth and Life Science

Aquatic macroinvertebrates bridge the gap in part between primary and secondary consumers, making them ecologically important for most aquatic systems. They are used as biotic indicators for water quality due to their sensitivity to pollutants and may be affected, specifically, by chloride ion concentrations in the water. Water quality can be evaluated by looking at species compositions and their respective tolerance values. To determine long-term effects of road salt on macroinvertebrate colonies, a total of 338 identified macroinvertebrates of 10 families (two generalized to class) at 9 sites were collected from before, after, and between three bridges on Turtle River …

Strategies For Successful Mangrove Living Shoreline Stabilizations In Shallow Water Subtropical Estuaries, Rebecca Fillyaw

Electronic Theses and Dissertations, 2020-2023

Mangrove living shorelines are an effective alternative to hard-armoring, which combat erosion while also increasing habitat. To improve the success of future mangrove deployments, an experimental Rhizophora mangle living shoreline was deployed within Mosquito Lagoon, FL. A factorial design was used to test the impact of mangrove age, breakwater presence, and mangrove placement on mangrove survival and growth. Environmental factors were monitored to isolate the reason for mangrove mortalities. Mangrove age was represented by 3 developmental stages: "seedlings" at 11-months-old, "transitionals" at 23-months-old, and "adults" between 35 and 47-months-old. Mixed mangrove age groups were included to identify if seedling survival …

Common Raven Impacts On Nesting Western Snowy Plovers: Integrating Management To Facilitate Species Recovery, Cheryl Strong, Kriss K. Neumann, Jenny L. Hutchinson, Jamie K. Miller, Amber L. Clark, Lena Chang, Joanna Iwanicha, Elizabeth Feucht, Matthew J. Lau, David J. Lauten, Sarah Markegard, Benjamin Pearl, David L. Sherer, Rachel Tertes, Susie Tharratt, Travis Wooten

Institute for Natural Resources Publications

The U.S. Pacific coast population of the western snowy plover (Charadrius nivosus nivosus; plover) has declined due to loss and degradation of coastal habitats, predation, and anthropogenic disturbance. The U.S. Fish and Wildlife Service listed the subspecies in 1993 as threatened under the Endangered Species Act due to the population declines and habitat loss. Predation of nests and chicks has been identified as an important cause of historic population declines, and thus, most predator management actions for this subspecies are focused on reducing this pressure. In recent years, common ravens (Corvus corax; ravens) have become the most common and pervasive …

Macroinvertebrate Responses To Hydrological Variation In Experimental Wetlands., Sergio A. Sabat-Bonilla

College of Graduate Studies: Theses & Dissertations

Predicted increases in the frequency of intense storms and periods of severe drought due to climate change represent a threat to wetland macroinvertebrate communities through alterations to the hydrological regime. I used experimental ponds to assess the effects of water permanence (i.e., duration of flooding) on the communities of aquatic macroinvertebrates. I predicted that permanent ponds would harbor higher diversity of longer-lived taxa whereas temporary ones will favor colonization by quick turnover, short-lived taxa and support lower consumer diversity. Results show differences in macroinvertebrate communities between permanent and temporary ponds can be mostly explained by hydrology and the amount of …

Monitoring Relationships Between Corticosterone And Snake Fungal Disease In Timber Rattlesnakes (Crotalus Horridus) In Western Kentucky, John Bromley Hewlett

Murray State Theses and Dissertations

Over the past four decades, emergent fungal diseases have been the most devastating relative to species declines and extinctions. While most research has focused on fungal diseases affecting amphibians and bats, less has focused on diseases like snake fungal disease (SFD), caused by Ophidiomyces ophiodiicola (Oo). SFD was first described in 2006 in North America within a Timber rattlesnake (Crotalus horridus) population in New Hampshire. Since then SFD has been documented in 19 US states, one US territory (Puerto Rico), and Europe. SFD causes high mortality in some species, including the Eastern Massasauga rattlesnakes (Sistrurus …

Males Of The Wolf Spider Rabidosa Rabida Use Two Mechanisms To Stun Females During Copulation, Daniel Schoenberg

Murray State Theses and Dissertations

The differences in energetic input between the sexes required to produce gametes translates to the differences in reproductive behavior and overall mating systems seen in a species. Females generally produce a few energetically and resource expensive eggs and typically choose a high-quality suitor to ensure she has high quality offspring. In contrast, males produce abundant energetically cheap sperm and attempt to fertilize as many eggs as possible in as many females as possible. Both sexes are trying to maximize their inclusive fitness, but the dichotomy of interests can lead to sexual conflict and perhaps extreme or unusual behaviors such as …

Characterizing The Host Usage And Development Of Ormia Lineifrons (Diptera: Tachinidae), Kyler J. Rogers

Murray State Theses and Dissertations

Insect communication systems are strongly driven by the evolution of signals or signal preferences. These systems rely on a signaler to truthfully emit signals for receivers to interpret. Often, these signals are conspicuously broadcasted. Conspicuous signals involved in animal communication are intended to attract mates, however, these signals are often exploited by eavesdroppers. Thus, many communication systems experience natural selection and sexual selection acting in opposite directions. New adaptations can arise in response to selective pressures, such as eavesdroppers, leading to co-evolving systems between eavesdroppers and hosts, for example. Understanding these systems can provide valuable insight into how unintended receivers …

Pollinator Ecology In Agroecosystems Of Eastern South Dakota, Isabela Beatriz Vilella-Arnizaut

Electronic Theses and Dissertations

Community structure contributes to ecosystem persistence and stability. To understand the mechanisms underlying pollination and community stability of natural areas in a human influenced landscape, a better understanding of the interaction patterns between plants and pollinators in disturbed landscapes is needed. Furthermore, understanding the potential conservation value in green spaces such as botanical gardens could assist in preserving and bolstering plant-pollinator interactions. Our study takes place in the Northern Great Plains which still retains extensive tracts of remnant temperate grassland habitat within a matrix of varying land-uses. First, we used a network-based approach to quantify how temperate grassland attributes and …

Pheasant Ecology In An Agricultural Landscape Of South Dakota, Sprih Harsh

Electronic Theses and Dissertations

Habitat loss and fragmentation are the greatest threats to wildlife conservation. Grasslands are among the most threatened ecosystems worldwide. The large-scale conversion of North American grasslands to cultivation has been strongly associated with declines of grassland bird populations. The ring-necked pheasant (Phasianus colchicus) is a common grassland bird which is negatively impacted by the conversion of grassland to cropland. Though pheasants are non-native to South Dakota, they have become naturalized in most of the state. However, with increases in agricultural intensification in South Dakota, indices of pheasant abundance from brood route surveys suggest that pheasant populations have declined to historically …

An Evaluation Of The Bighorn Sheep Population In Badlands National Park, Austin J. Wieseler

Electronic Theses and Dissertations

Within the last century, bighorn sheep (Ovis canadensis) in the badlands ecosystem of western South Dakota have been subjected to complete extirpation, reintroduction, disease die-offs, genetic bottlenecking, and population augmentation. Subsequently, the population in Badlands National Park (BNP) appears to have recovered, but it was unknown to what degree past events had influenced the population. From 2017-2019, we conducted research on 5 subherds within 2 management units in BNP to 1) survey for the presence of respiratory pathogens and estimate the prevalence of other potentially infectious diseases; 2) assess adult and lamb survival and cause-specific mortality; 3) estimate population size …

Monitoring Landscape And Spectral Dynamics Of Subtropical Freshwater Wetlands That Have Undergone Hydrological Restoration, Sarah Parker

Electronic Theses and Dissertations, 2020-2023

Over the last century, millions of hectares of wetlands have been lost due to urban development and agricultural activities throughout the world. In the U.S., efforts have been made by federal and state legislation to restore wetland habitat in exchange for development on wetlands. To restore ecosystem function by reestablishing hydrological metrics (e.g., groundwater level fluctuations), wetland restoration aims to facilitate the growth of wetland vegetation to approximate the original conditions as a proxy for ecological integrity. In 1992, the first landscape-scale off-site mitigation project, the Disney Wilderness Preserve (DWP) was funded by the Walt Disney Company in Poinciana, Florida. …

Correlations In Microplastic Abundance Between Water, The Eastern Oyster, Crassostrea Virginica, And Their Biodeposits In A Dynamic Florida Estuary, Casey Craig

Electronic Theses and Dissertations, 2020-2023

Estuaries have been identified as hotspots of microplastic pollution because they are transitional zones where coastal freshwater and oceans converge. Microplastics (MP) are transported through estuaries by a dynamic series of forces such as surface flow and tides, which influence MP abundances and trends. The eastern oyster, Crassostrea virginica, is an estuarine bivalve known to ingest MP, resulting in negative impacts on organism physiology. I investigated MP pollution as a threat to C. virginica in a dynamic Florida estuary, the Indian River Lagoon (IRL), and determined there are both regional and small-scale spatial and temporal fluctuations in MP abundance. Tributaries …

Seed Bank Composition Within Two Sagebrush Communities: A Comparison Of Drought, Microsite, And Aboveground Community Effects, Allison Marie Nunes

Cal Poly Humboldt theses and projects

Soil seed banks are critical biodiversity repositories for many dryland plant communities. Understanding how environmental factors alter seed bank composition can provide valuable information on ecological processes within a community and be useful for creating land management strategies. Using the seedling emergence method, I characterized the seed bank of two adjacent dryland plant communities that vary in dominant sagebrush species, structure, and function. Specifically, within an Artemisia arbuscula dominated community and Artemisia cana dominated community, I assessed the influence of three environmental factors on each seed bank: experimentally imposed drought, shrub microsites (compared to interspaces), and aboveground vegetation. Within the …

Evaluating Immaturity Risk In Young Stands Of The Serotinous Knobcone Pine (Pinus Attenuata), Katherine Marlin

Cal Poly Humboldt theses and projects

As wildfire becomes increasingly frequent, many plant populations risk local extirpation if fire recurs too soon, a problem dubbed “immaturity risk”. We studied the regeneration of a serotinous conifer species, knobcone pine (Pinus attenuata), as a function of the time between high-severity fires (6-79 years). We evaluated age, cone production, and regeneration at two burned sites in northern California, the Ranch Fire (2018) in Mendocino National Forest, and the Carr Fire (2018) in Whiskeytown National Recreation Area. We found an average of 30.5 filled seeds in closed, brown cones (42% viability of filled seeds). The bulk of the …

Social Comparison Tendencies And The Reward Value Of Same-Sex Beauty Among Heterosexual Women, Melissa M. Martin Ms.

Cal Poly Humboldt theses and projects

Previous studies have suggested that heterosexual women, but not heterosexual men, find same sex beauty rewarding. This finding has been attributed to a “greater bisexual interest among heterosexual women”, but no other explanations have been offered or tested. The current study aimed to explore social comparison tendencies as a potential alternate explanation to this previously observed finding. Twenty-three heterosexual women completed a series of questionnaires designed to assess their social comparison tendencies (the social comparison orientation scale, the physical appearance comparison scale, and the intrasexual competition scale). They also completed a “pay-per-view” keypress task to measure the reward value of …

Noninvasive Genetic Sampling With A Bayesian Spatial Capture-Recapture Analysis To Estimate Abundance Of Roosevelt Elk (Cervus Canadensis Roosevelti), Makenzie Henk

Cal Poly Humboldt theses and projects

Determining abundance of Roosevelt elk (Cervus canadensis roosevelti) in central Humboldt County, California has presented a unique challenge to wildlife managers due to the dense forest habitat and the animals’ elusive behavior. As the elk population has increased, so has human-wildlife conflict, and wildlife agencies need efficient and repeatable methods for determining abundance to inform management decisions. Traditional monitoring methods such as helicopter surveys are ineffective due to low sighting probability and strong behavioral responses to the aircraft. They also often lead to biased sex ratios when the distribution of males and females varies across the landscape. Non-invasive …

Impact Of The North American Monsoon On Molt Migrant Passerines, Liuqingqing Yang

Honors Theses

Breeding, molt, and migration place considerable yearly demands on migrating passerines in North America. Due to conflicts in energy allocation, many species have evolved migration strategies that prevent temporal overlap in these processes. However, there is recent evidence that some passerines which breed in western North America migrate to intermediate stopover sites to carry out molt, conflating molt and migration. Factors influencing the evolution of such a strategy are believed to include both aridity on breeding grounds and dependable flushes of late-summer productivity in the southwestern United States and northwestern Mexico. This productivity occurs due to the brisk rainfall of …

Morphological Variance In Mouthparts And Foraging Behavior In Bumblebees, Ye Jin Lee

Honors Theses

Bumblebees (Hymenoptera: Apidae: Bombus) show an incredible degree of size variation within and between species. Individuals from the same hive may vary up to 10-fold in mass. This variation allows individuals to specialize in foraging on different flowers suited to their morphology. However, as different species have different foraging behaviors, their variation in mouthparts and scaling of mouthparts to body size may have been under different kinds of stabilizing selection as they adapted to collect nectar from flowering plants over evolutionary time. Here, we examined the scaling relationships between body size and mouthpart structures, and the variation in mouthpart shape …

Contrasting Patterns Of Nutrient Limitation In The Littoral And Pelagic Zones Of Mesotrophic Maine Lakes, Grace C. Neumiller

Honors Theses

Intense nutrient loading of nitrogen (N) and phosphorus (P) causes sudden regime shifts in freshwater ecosystems from clearwater to turbid conditions with frequent cyanobacterial blooms. Characterization of nutrient limitation patterns of primary productivity in these ecosystems is necessary for effective management of algal blooms. However, much of this research has focused on pelagic habitats. The influence of lake habitat (i.e. benthic littoral versus pelagic zones) on nutrient limitation of primary production in mesotrophic lakes is largely unknown, particularly in contrast to research on pelagic nutrient limitation in eutrophic systems. Using paired nutrient diffusing substrata and mesocosm experiments, we measured chlorophyll- …

Effects Of Emerging Contaminants On Centrarchidae And Catostomidae In Midwestern Rivers: A Multiple Biomarker Approach, Camden Garret Nix

Masters Theses

Natural habitats of fish are gradually declining due to land use and pollution caused by industrial wastes, intensive agriculture and contamination from sewage systems. The United States has 14,780 wastewater treatment facilities that discharge effluent into navigable waters, and in some cases these discharge waters represent a considerable proportion of the water system flow. These activities make it critical to discern the effects of pollutants that are entering our waterways at a consistent rate, such as 17β-estradiol (E2) and nickel, on aquatic organisms. To determine the effects of 17β-estradiol on endocrine disruption in fish, Bluegill Sunfish (Lepomis macrochirus) …

Effects Of Wastewater Effluent On Fish Fin Morphology Of Larval Fathead Minnows (Pimephales Promelas) And Swimming Performance Of Smallmouth Buffalo (Ictiobus Bubalus), Seth Michael Bogue

Masters Theses

The Sangamon River flows across central Illinois and is mostly free flowing except in the city of Decatur where it is impounded to form Lake Decatur. The Sanitary District of Decatur (SDD) is located approximately three miles downstream of the Lake Decatur dam. For a significant portion of the year, the stretch of the Sangamon River downstream of SDD is dominated by effluent due to limited discharge from the Lake Decatur dam. This has resulted in heavy nutrient loading, most notably phosphorus, and elevated levels of nickel and other compounds in the downstream section of the river. Smallmouth buffalo ( …

Genetic Relatedness Can Alter The Strength Of Plant-Soil Feedbacks, Kelly M. Clark

Masters Theses

Intraspecific variation may play a key role in understanding the relationships between plants and their interactions with soil microbial communities. The effects that soil-microbes have on individuals can venerate variation across individuals in their responsiveness. I explored how relatedness alters plant-soil feedbacks in established Solidago altissima clones grown in a common garden. Seedlings of known parentage were inoculated with soils from the maternal, paternal, or unrelated clones and compared to autoclaved control inocula. I found that the soil inocula generated from S. altissima had an overall negative effect of seedling biomass. Furthermore, seedlings inoculated with maternal or paternal soils experienced …

Phenotypic Characterization Of Table Mountain (Pinus Pungens) And Pitch Pine (Pinus Rigida) Hybrids Along An Elevational Gradient In The Blue Ridge Mountains, Virginia, Alexander L. Brown

Theses and Dissertations

Hybridization has played a long-standing role in the evolution of both plant and animal species and allows for the sharing of genetic information between lineages. Here, potential hybridization of a species endemic to the Appalachian Mountains, Table Mountain pine (Pinus pungens), and pitch pine (Pinus rigida) was investigated along an elevational gradient, through the use of phenotypic measurements: cone length, cone width, and needle length. Phenotypes were used to identify hybrids in a three-tiered elevational sampling method at two sites in Shenandoah National Park with the use of linear discriminant analysis. It was found that hybridization …

Effects Of Abiotic And Biotic Factors On Hornworm Distributions, Emelia O. Kusi

Theses and Dissertations

Determining the drivers of species occurrences is a central topic in ecology. Both abiotic and biotic factors are important predictors of species distributions, yet most species distribution models consider abiotic variables only. In this study, the influence of abiotic and biotic factors on current distributions of herbivores, Manduca sexta, and Manduca quinquemaculata, their major cultivated and wild host plants, and a parasitoid, Cotesia congregata, was quantified using an ensemble of three models (generalized linear model, maximum entropy, and random forest). The predictive ability of abiotic-only, biotic-only, and abiotic-biotic models was evaluated. Winter temperatures and precipitation (i.e., precipitation of …

Water Clarity At The River-Estuary Transition Zone: A Comparative Study Of The James, Mattaponi, And Pamunkey Sub-Estuaries, Rachel Henderson

Theses and Dissertations

Water clarity is a key parameter for monitoring water quality and often used to assess habitat suitability for submerged aquatic vegetation (SAV). Light attenuation, a measure of water clarity, is impacted by colored dissolved organic matter (CDOM), and by suspended particulates which include living and non-living components. We anticipated that the relative importance of these factors in regulating light attenuation would vary among the upper portions of three sub-estuaries differing in morphometry, hydrology, and degree of human influence. The James is characterized by eutrophic conditions and high algal abundance, whereas the Mattaponi and Pamunkey exhibit lower phytoplankton production. The Mattaponi …

The Reconstruction Of Hatchery Creek: Effects On Macroinvertebrate And Fish Community Dynamics, Patrick Vrablik

Murray State Theses and Dissertations

Hatchery Creek is a restored stream in Jamestown, KY that drains Wolf Creek National Fish Hatchery. The previous degraded channel of Hatchery Creek caused large sediment plumes in the Lower Cumberland River and was restored to decrease sediment loss and provide the opportunity for a self-sustaining trout population. I predicted that the increased amount of habitat would increase taxa richness, abundance and biomass of macroinvertebrates. Macroinvertebrates were monitored in three periods; the degraded period, a one-year recovery period, and a restored period using surber and kicknet samples in order to determine biomass, abundance, diversity, taxa richness, and macroinvertebrate biotic index. …

Use Of Lymesim 2.0 To Assess The Potential For Single And Integrated Management Methods To Control Blacklegged Ticks (Ixodes Scapularis; Acari: Ixodidae) And Transmission Of Lyme Disease Spirochetes, Shravani Chitineni, Elizabeth R. Gleim, Holly D. Gaff

Undergraduate Honors Theses

Annual Lyme disease cases continue to rise in the U.S. making it the most reported vector-borne illness in the country. The pathogen (Borrelia burgdorferi) and primary vector (Ixodes scapularis; blacklegged tick) dynamics of Lyme disease are complicated by the multitude of vertebrate hosts and varying environmental factors, making models an ideal tool for exploring disease dynamics in a time- and cost-effective way. In the current study, LYMESIM 2.0, a mechanistic model, was used to explore the effectiveness of three commonly used tick control methods: habitat-targeted acaricide (spraying), rodent-targeted acaricide (bait boxes), and white-tailed deer targeted acaricide (4-poster …