Terrestrial and Aquatic Ecology Commons^™

Emerald Bowfin Amia Ocellicauda Ecology In Three Minnesota Lakes: Abundance, Age Analysis, Diet Composition, And Stable Isotope Food Web, Griffin Blegen

Biology Graduate Theses

The Emerald Bowfin Amia ocellicauda is a predatory fish species native to Minnesota that has often been discriminated against. This research expands ecological knowledge of Bowfin in Minnesota and provides population data to guide future management. Bowfin were sampled in the spring of 2024 and 2025 and a multi-census mark–recapture model was used to estimate abundance in three lakes. Estimated populations were 196 individuals in Little Toad Lake (95% CI: 116, 242) or 4.4 fish/littoral ha (95% CI: 2.7,5.7), 657 in Lake Sarah (95% CI: 436, 1014) or 4.2 fish/littoral ha (95% CI: 3.0, 6.7), and 612 in Gun Lake …

Characterization Of The Genetic Diversity Of Curlyleaf Pondweed (Potamogeton Crispus L.) In The Contiguous United States And Canada And Analysis Of Possible Hybrid Potamogeton Crispus Lineages, Mallory M. Kaiser

All Graduate Theses, Dissertations, and Other Capstone Projects

Curlyleaf Pondweed (Potamogeton crispus L.) is a prolific invasive species that has spread across the United States and into parts of Canada since its introduction to North America in the 1840s. It causes extensive economic and environmental damage across its invasive range, and its control and eradication are of utmost importance to agricultural, ecological, recreational, and transportational stakeholders. Developments in molecular ecology and invasive management have found that genetic diversity and hybridization of aquatic macrophytes may affect their susceptibility to herbicide treatments, and genotype or lineage identification are important control variables that must be considered in field and …

Walleye And Sauger Movement And Entrainment In Lewis And Clark Lake, William Joseph Radigan

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Walleye Sander vitreus and Sauger Sander canadensis are both socioeconomically important sportfish species in Lewis and Clark Lake, an interjurisdictionally managed mainstem Missouri River reservoir fishery. Since 2011, adult catch per unit effort (CPUE) of both Walleye and Sauger has remained at approximately 50% of pre-2011 levels. A presumed reason for the suppressed CPUE of adult Walleye and Sauger is substantial entrainment of larval and adult fish resulting from the reservoir’s high turnover rate (7.2 d). Acoustic telemetry was used to quantify adult movement and entrainment and ichthyoplankton trawls were used to assess larval entrainment. Relative importance of factors driving …

Modifying The Comb, Rethinking The Install: Integrated Approaches To Honey Bee Colony Establishment And Winter Survival, Shelby A. Kittle

Department of Entomology: Dissertations, Theses, and Student Research

The European, or Western honey bee (Apis mellifera L.) plays a vital role in global ecosystems and agriculture, providing essential pollination services and producing valuable hive products. However, honey bee colony losses have escalated worldwide, but particularly across the United States due to various stressors, including biotic and abiotic factors, mismanagement, and environmental challenges. This thesis investigates key challenges in honey bee management and explores solutions aimed at improving colony health and productivity.

Chapter 1 provides an overview of the beekeeping industry, detailing its economic importance, services, and products, as well as the many challenges faced by beekeepers. It …

Site-Specific Space Use And Resource Selection By Black Vultures (Coragyps Atratus) In The Southeastern Usa, Betsy Evans, John S. Humphrey, Eric A. Tillman, Michael L. Avery, Bryan M. Kluever

United States Department of Agriculture Wildlife Services: Staff Publications

North American populations of Black Vultures Coragyps atratus have increased and expanded their distribution in the southern and eastern USA. In conjunction with these patterns has been a rise in human–vulture conflicts. To improve our understanding of space use patterns and better inform management, we evaluated the movements of Black Vultures (n = 23) in the southeastern USA using a long-term GPS tracking database. Our specific objectives were to: (1) quantify home-range sizes in relation to season and geographical study location and (2) examine within-home-range resource selection to identify landscape and anthropogenic factors influencing roost and diurnal space use. …

Effect Of Walleye Fry Stocking On Future Gillnet Cpue, Alexander Barker

Journal of Earth and Life Science

Walleye Sanders vitreus for many states, is a key attractant of anglers from around North America. Due to immense popularity, management efforts have been conducted to maintain Walleye populations, especially in the form of stocking. The purpose of this study is to analyze the effect of Walleye fry stocking on gillnet catch per unit effort (CPUE). A total of 90 lakes were analyzed for this study within three defined regions of Minnesota, 30 from each region. The regions chosen for this study are the Minnesota Department of Natural Resources northern pike Esox lucius regulation regions which consist of the Southern, …

Impact Of Road Infrastructures On The Abundance Of Common Chameleon Populations, Pablo García-Quevedo, Francisco Díaz-Ruiz, Antonio Román Muñoz, Jesús Duarte, Adrián Martín-Taboada, José-María García-Carrasco, Miguel Ángel Farfán

Human–Wildlife Interactions

The common chameleon (Chamaeleo chamaeleon) is a threatened species in Spain. The loss and transformation of their traditional habitats are among the main causes of its decline. Linear infrastructures, such as roads and highways, cause direct habitat loss, roadkill, and fragmentation of populations by acting as an artificial barrier. In this study, we investigated the potential effect of 2 high-speed road infrastructures in southern Spain on local populations of common chameleons. A total of 34 grids of 1x1 km were sampled, differentiating between grids without road presence (n = 17) and grids with road presence (n …

Evaluation Of Mitigation Translocation As A Management Tool To Reduce Conflicts Between Humans And American Kestrels, Brian E. Washburn

United States Department of Agriculture Wildlife Services: Staff Publications

Raptor‐aircraft collisions (bird strikes) pose a serious safety risk to civil aircraft. Even smaller raptors, such as American kestrels (Falco sparverius), can be problematic within airport environments. Given widespread declines in kestrel populations, public interest, logistical and financial constraints, and other factors, managing kestrels at airports presents some unique challenges. I conducted a study to determine which biological (e.g., age and sex of the bird) and logistical factors (e.g., month and translocation distance) might influence the return of American kestrels live‐captured and translocated from 42 civil airports and military airbases within the contiguous USA during 2016–2021. American kestrels …

Population Response Of Eastern Wild Turkey To Removal Of Wild Pigs, Matthew T. Mcdonough, Stephen J. Zenas, Robert A. Gitzen, Mark D. Smith, Kurt C. Vercauteren, Stephen S. Ditchkoff

United States Department of Agriculture Wildlife Services: Staff Publications

There is insufficient understanding of interspecific interactions with the eastern wild turkey (Meleagris gallopavo silvestris) and wild pigs (Sus scrofa). Wild pigs compete with wild turkeys and predate nests and adults; however, population‐level effects on wild turkeys are not clear. Using cameras, we assessed responses of wild turkey populations to wild pig removal in central Alabama, USA, from 2018–2021. We compared wild turkey relative abundance and occupancy on 3 large‐scale pigremoval treatment sites (3,407–5,531 ha) relative to a control site (2,510 ha) during 1 pre‐treatment year and 2 posttreatment years, with analyses including a covariate expressing the cumulative …

The Devil You Know And The Devil You Don’T: Current Status And Challenges Of Bovine Tuberculosis Eradication In The United States, Daniel J. O'Brien, Tyler C. Thacker, Liliana C.M. Salvador, Anthony G. Duffiney, Suelee Robbe‑Austerman, Mark S. Camacho, Jason E. Lombard, Mitchell V. Palmer

United States Department of Agriculture Wildlife Services: Staff Publications

Having entered into its second century, the eradication program for bovine tuberculosis (bTB, caused by Mycobacterium bovis) in the United States of America occupies a position both enviable and daunting. Excepting four counties in Michigan comprising only 6109 km2 (0.06% of US land area) classified as Modified Accredited, as of April 2022 the entire country was considered Accredited Free of bTB by the US Department of Agriculture for cattle and bison. On the surface, the now well-described circumstances of endemic bTB in Michigan, where white-tailed deer (Odocoileus virginianus) serve as a free-ranging wildlife maintenance host, may appear to be …

Changes In Wild Pig (Sus Scrofa) Relative Abundance, Crop Damage, And Environmental Impacts In Response To Control Efforts, Joseph W. Treichler, Kurt C. Vercauteren, Charles R. Taylor, James C. Beasley

United States Department of Agriculture Wildlife Services: Staff Publications

Background

As the population and range of wild pigs (Sus scrofa) continue to grow across North America, there has been an increase in environmental and economic damages caused by this invasive species, and control efforts to reduce damages have increased concomitantly. Despite the expanding impacts and costs associated with population control of wild pigs, the extent to which wild pig control reduces populations and diminishes environmental and agricultural damages are rarely quantified.The goal of this study is to quantify changes in wild pig relative abundance and subsequent changes in damages caused by invasive wild pigs in response to …

Evaluation Of Roost Culling As A Management Strategy For Reducing Invasive Rose‑Ringed Parakeet (Psittacula Krameri) Populations, C. Janes Anderson, Leonard A. Brennan, William P. Bukoski, Steven C. Hess, Clayton D. Hilton, Aaron B. Shiels, Shane Siers, Bryan M. Kluever, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Rose-ringed parakeets (Psittacula krameri) are one of the most widespread invasive avian species worldwide. This species was introduced to the island of Kaua‘i, Hawai‘i, USA, in the 1960s. The rapidly increasing population has caused substantial economic losses in the agricultural and tourism industries. We evaluated the efficacy of a roost culling program conducted by an independent contractor from March 2020 to March 2021. We estimated island-wide minimum abundance was 10,512 parakeets in January 2020 and 7,372 in April 2021. Over 30 nights of culling at four roost sites, approximately 6,030 parakeets were removed via air rifles with 4,415 …

Predator Telemetry Informs Temporal And Spatial Overlap With Stocked Salmonids In Lake Huron, David G. Fielder, Todd A. Hayden, Thomas R. Binder, Brian S. Dorr, Heidi A. Currier

United States Department of Agriculture Wildlife Services: Staff Publications

Double-Crested Cormorants (Phalacrocorax auratus), Walleyes (Sander vitreus), and Lake Trout (Salvelinus namaycush) are migratory predators that undergo extensive movements in Lake Huron. Stocking of juvenile salmonid fish (Oncorhynchus and Salmo sp.) is an important component of fishery management in Lake Huron and assessing the spatial and temporal extent of predator movements is a useful consideration for determining when and where to stock juvenile fish to reduce predation and maximize survival. Previous investigation indicated that some Walleyes migrate to the main basin of Lake Huron in spring from Saginaw Bay. Similarly, telemetry studies of Lake Trout movement in Lake Huron have …

The Links To Cancer: How Golf Became Dangerous And What We Can Do To Save The Game, Meredith Boos

Undergraduate Theses, Professional Papers, and Capstone Artifacts

This study is a comprehensive meta-analysis on health claims linked to exposure to golf courses, more specifically the chemicals used to maintain their appearance. It provides a brief history of the golf industry and how its growth exacerbated the environmental impact as well as an explanation of the legal landscape that will affect golf course management. Golf courses can disrupt local ecologies, contaminate ground water, rivers, lakes and streams with run-off, and be responsible for the bioaccumulation of chemicals which remain dangerous for decades. Despite the adverse effects of golf courses on the environment, there remains an opportunity to transform …

The Influence Of Income And Loss On Hunters' Attitudes Towards Wild Pigs And Their Management, Samantha Leivers, Keith M. Carlisle, Rachel L. Connally, Maureen G. Frank, John M. Tomeček

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are one of the most pervasive invasive species in North America. Wild pigs pose a threat to crops, livestock, and the environment, but also provide recreational hunting opportunities. There are avenues for some stakeholder groups to generate income from wild pigs, however, stakeholders vary in attitudes towards wild pigs and their management. We investigated whether financial loss and income resulting from wild pigs influenced hunter stakeholder attitudes towards their management in Texas. We examined how land use influenced hunting landowner attitudes towards wild pigs. We analyzed 22,176 responses (8,707 landowners, 13,469 nonlandowners) fromTexas hunters …

A Novel Parakeet‐Selective Feeder For Control Of Invasive Psittacines, C. Jane Anderson, Eric A. Tillman, William P. Bukoski, Steven C. Hess, Leonard A. Brennan, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Over 40 species of parrots, members of order Psittaciformes, have established nonnative populations globally. Monk parakeets (Myiopsitta monachus) are among the most invasive bird species worldwide. In their introduced range, populations of monk parakeets have caused negative impacts on native species, habitats, economies, and human safety. Lethal population management has been complicated by the intelligence of monk parakeets, as they quickly alter behavior to avoid risks. Further, lethal control programs have been halted due to public controversy, as parakeets are highly charismatic. The contraceptive DiazaCon has been demonstrated to effectively reduce fertility in monk parakeets and other psittacines. In field …

Impacts Of Sea Ice Loss On Polar Bear Diet, Prey Availability, Foraging Behaviors, And Human-Bear Interactions In The Arctic, Jasmin Chen

Master's Projects and Capstones

Anthropogenic-induced climate change has warmed the Arctic 2-3 times faster than the rest of the world, causing sea ice declines that introduce challenges for specialist species, such as polar bears, in adapting to rapid environmental changes. Comparative and quantitative analyses of three Hudson Bay polar bear subpopulations were used to determine the impacts of sea ice loss on polar bear diet, prey availability, foraging behaviors, and human-bear interactions in the Arctic. The study reveal that Hudson Bay polar bears experience the most severe impacts from sea ice declines, resulting in a 30% population decline. Due to their smaller body size, …

Spatiotemporal Factors Affecting The Occupancy And Phenology Of A Declining Songbird (Bachman's Sparrow - Peucaea Aestivalis) At The Western Extent Of Its Range, Liam G. Wolff

Electronic Theses and Dissertations

The Bachman’s Sparrow (Peucaea aestivalis) is a declining songbird that occurs throughout the southeastern United States. Bachman’s Sparrow is a Species of Greatest Conservation Need in Texas, but information crucial to management efforts, such as factors affecting their detectability and occupancy, is lacking. I investigated the predictors of Bachman’s Sparrow occupancy and phenology in Texas using detections from autonomous recording units coupled with site characteristics and weather data. My results indicate that Bachman’s Sparrow occupancy is associated with increasing herbaceous ground cover and decreasing basal area, distance to the nearest source population, and basal area when canopy height …

Western Prairie Fringed Orchid Management, Ecology, And Decline At Mormon Island, Andrew J. Caven

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The western prairie fringed orchid (Platanthera praeclara Sheviak & M. L. Bowles; WPFO) was first detected in a vegetative state on Mormon Island in 1978 and identification was confirmed following a mass flowering event in 1982. From a high count of ~60 plants the WPFO slowly declined and has not been observed since 2000 despite flowering season surveys conducted in 15 of the last 20 years. We explore the natural history of the WPFO in the contexts of Mormon Island to establish potential causes for its apparent disappearance and evaluate the possibility it persists in some capacity. Our investigation …

Optimizing Management Of Invasions In An Uncertain World Using Dynamic Spatial Models, Kim M. Pepin, Amy J. Davis, Rebecca S. Epanchin-Niell, Andrew M. Gormley, Joslin L. Moore, Timothy J. Smyser, H. Bradley Shaffer, William L. Kendall, Katriona Shea, Michael C. Runge, Sophie Mckee

United States Department of Agriculture Wildlife Services: Staff Publications

Dispersal drives invasion dynamics of nonnative species and pathogens. Applying knowledge of dispersal to optimize the management of invasions can mean the difference between a failed and a successful control program and dramatically improve the return on investment of control efforts. A common approach to identifying optimal management solutions for invasions is to optimize dynamic spatial models that incorporate dispersal. Optimizing these spatial models can be very challenging because the interaction of time, space, and uncertainty rapidly amplifies the number of dimensions being considered. Addressing such problems requires advances in and the integration of techniques from multiple fields, including ecology, …

Evaluating Avian Use Of Cover Crops In The Corn Belt, Megan Figura

Electronic Theses and Dissertations

The tallgrass prairie of North America has changed drastically since colonial settlement, with up to 99% of this region converted for agriculture and other land-uses. Concurrent with grassland conversion, grassland birds have experienced the most extreme, consistent, and widespread population declines of any avian guild. Agricultural lands in the U.S. Midwest were able to provide adequate habitat for several bird species until the 1950’s; however, altered and intensified management practices have degraded much of remaining suitable habitat and undermined ecosystem functions. Consequently, many grassland birds have been identified as Species of Greatest Conservation Need (SGCN) in many State Wildlife Action …

Rodents In Agriculture: A Broad Perspective, Gary Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

The largest taxonomic group of mammals is rodents, with over 2200 species known around the world [1]. More recently, it was stated that over 2500 species exist [2]. Many species exist on all continents, with the exception of Antarctica. Rodents have adapted to all ecosystems of the world, including tundra, alpine, temperate forests, grasslands, arid regions, and aquatic systems. They provide many ecosystem functions, including soil aeration and mixing, seed and spore dispersal, vegetation succession, and being an important food source for predatory animals. Some species of rodents are even consumed by people in some parts of the world. Most …

Joint Management Of Upland & Aquatic Habitat For The California Red-Legged Frog & California Tiger Salamander, Kyle E. Verblaauw

Master's Projects and Capstones

As federally and state protected amphibians, the California tiger salamander (Ambystoma californiense) and the California red-legged frog (Rana draytonii) are recipients of ample management focus. Both species face a variety of threats, including habitat loss and alteration, introduction of non-native species, spread of disease, and effects of climate change. While management plans for the California tiger salamander and California red-legged frog exist, they frequently do not consider both species in tandem and often contain multiple shortcomings. This document aims to address the shortfalls of current management by providing practical recommendations for jointly managing the upland and …

Implications Of Condition Shifts On Shallow Lakes, Alicia Skolte

Biology Graduate Theses

Shallow lakes have undergone condition shifts throughout time by natural causes, management actions, or a combination of the two. Because shallow lakes are especially vulnerable to shifts towards turbid conditions, management actions on shallow lakes have focused on water level/retainment, biomanipulations, the management/removal of non-native species, and land-use changes. This review compiles a summary on ecosystem shifts including a discussion on the frequency of shifts historically and the importance and causes of those shifts, trophic cascades, and the influence of introduced species in shallow lakes. This review will then examine case-studies of management-linked shifts and explain current shift theory. Next, …

Comparing Management Programs To Reduce Red–Tailed Hawk Collisions With Aircraft, Brian Washburn, Craig K. Pullins, Travis L. Guerrant, Gregory J. Martinelli, Scott F. Beckerman

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife-aircraft collisions (wildlife strikes) pose a serious safety risk to aircraft. Raptors (i.e., hawks and owls) are one of the most frequently struck guilds of birds within North America. Although raptors (most notably red-tailed hawks [Buteo jamaicensis]) are commonly managed at most airports and military bases, there is no scientific information available regarding comparisons of the efficacy of raptor management programs for reducing raptor-aircraft collisions. Therefore, we conducted a study to examine the efficacy of 2 raptor hazard management programs implemented at Chicago's O'Hare International Airport (ORD). The first raptor management program (Phase I) occurred during January 2010–June 2013 and …

Understanding Metrics Of Stress In The Context Of Invasion History: The Case Of The Brown Treesnake (Boiga Irregularis), Natalie Claunch, Ignacio Moore, Heather L. Waye, Laura Schoenle, Samantha J. Oakey, Robert N. Reed, Christina Romagosa

Biology Publications

Invasive species can exert rapid depletion of resources after introduction and, in turn, affect their own population density. Additionally, management actions can have direct and indirect effects on demography. Physiological variables can predict demographic change but are often restricted to snapshots-in-time and delayed confirmation of changes in population density reduces their utility. To evaluate the relationships between physiology and demography, we assessed metrics of individual and demographic stress (baseline and 1-h corticosterone (CORT), body condition and bacterial killing ability) in the invasive snake Boiga irregularis on Guam collected in intervals of 10–15 years. We also assessed potential discrepancies between different …

Effects Of Social Structure And Management On Risk Of Disease Establishment In Wild Pigs, Anni Yang, Peter E. Schlichting, Bethany Wight, Wesley M. Anderson, Sarah M. Chinn, Mark Q. Wilber, Ryan S. Miller, James C. Beasley, Raoul Boughton, Kurt C. Vercauteren, George Wittemyer, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

1. Contact heterogeneity among hosts determines invasion and spreading dynamics of infectious disease, thus its characterization is essential for identifying effective disease control strategies. Yet, little is known about the factors shaping contact networks in many wildlife species and how wildlife management actions might affect contact networks.

2. Wild pigs in North America are an invasive, socially structured species that pose a health concern for domestic swine given their ability to transmit numerous devastating diseases such as African swine fever (ASF). Using proximity loggers and GPS data from 48 wild pigs in Florida and South Carolina, USA, we employed a …

Black Bear, Jimmy D. Taylor, James P. Phillips

Wildlife Damage Management Technical Series

The American black bear (Ursus americanus, Figure 1) is a challenging species for wildlife agencies to manage due to its size, intelligence, extensive range, food habits, and adaptability, as well as societal views. In North America alone, agencies receive more than 40,000 complaints about black bear annually. Black bears are known as ‘food-driven’ animals, meaning most conflicts result from a bear’s drive to meet its nutritional needs. Not surprisingly, an overwhelming proportion of conflicts are related to their use of anthropogenic (human) food sources, such as garbage, bird food, and crops. Understanding what drives human-bear conflict is the first part …

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …

Effect Of Beaver On Brook Trout Habitat In North Shore, Lake Superior Streams, Kathryn Renik

Biology Graduate Theses

In Minnesota, North American Beavers Castor canadensis (hereafter Beaver) are considered to have an overall negative affect on native Brook Trout Salvelinus fontinalis. Brook Trout provide a valued and productive sport fishery to the North Shore streams of Lake Superior and since revival of the Beaver population from past trapping and timber harvest, a reexamination of the complex ecological relationship where the two taxa interact is imperative. Suitable Brook Trout habitat is characterized by cold, spring- fed water with silt-free rocky substrate and abundant cover, all of which Beaver may directly, or indirectly, affect. Data collection occurred on 79 (200 …