Population Biology Commons^™

A Coupled Model Of Population, Poaching, And Economic Dynamics To Assess Rhino Conservation Through Legal Trade, Henry Doyle, Kylie Champagne, Ditto Rajpal, Grace Seebeck, David J. Gerberry

Spora: A Journal of Biomathematics

Rhinoceros populations in Africa are in peril largely due to the high value of their horns and the poaching that ensues. The strategy of legalizing the international trade of rhino horn is receiving increased support among both the people and government officials in Africa. Many in the international conservation community remain opposed to the idea. The legalization strategy is straightforward in theory: legalizing the trade of rhino horn will introduce a large quantity of horn to the market, the increased supply will lead to lower prices for rhino horn, and lower prices will reduce the overall poaching pressure these animals …

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

Theses, Dissertations and Capstones

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

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

Theses, Dissertations and Capstones

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

Mark-Recapture Methods In Eastern Diamondback Rattlesnake (Crotalus Adamanteus) Monitoring, Carissa J. Adams

Theses, Dissertations and Capstones

Eastern diamondback rattlesnakes (Crotalus adamanteus; EDB) are an imperiled species native to the Southeastern United States longleaf pine (Pinus palustris) ecosystem. Several markrecapture methods have been used range-wide in hopes of increasing knowledge on their population numbers. I explored the efficacy of two mark-recapture methods (scale cauterization and dorsal head photography) using the Marine Corps Recruit Depot, Parris Island, SC EDB population in this multi-part study. The first method I evaluated was ventral scale branding, which has been widely implemented without knowledge of brand permanence. I classified misidentification errors at capture status (new versus recapture) and …

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

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

Limitations Of Invasive Snake Control Tools In The Context Of A New Invasion On An Island With Abundant Prey, Shane R. Siers, Melia G. Nafus, Jereid E. Calaor, Rachel M. Volsteadt, Matthew S. Grassi, Megan Volsteadt, Aaron F. Collins, Patrick D. Barnhart, Logan T. Huse, Amy A. Yackel Adams, Diane L. Vice

United States Department of Agriculture Wildlife Services: Staff Publications

In October 2020, a new population of invasive brown treesnakes (Boiga irregularis) was discovered on the 33-ha Cocos Island, 2.5 km off the south coast of Guam, United States. Cocos Island is a unique conservation resource, providing refuge for many lizards and birds, including endangered species, which were extirpated from mainland Guam by invasive predators including brown treesnakes. We sought to evaluate the usefulness of toxic baiting with acetaminophen-treated carrion baits and cage trapping, common tools for the control of brown treesnakes on mainland Guam, as potential eradication tools on Cocos Island. We evaluated multiple bait types and …

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. …

Antipredator Blood-Squirting Defense In Horned Lizards (Phrynosoma): Chemical Isolation Of Plasma Component(S), Pogonomyrmex Ant Dietary Origin, And Evolution, Wade C. Sherbrooke, Bruce A. Kimball

United States Department of Agriculture Wildlife Services: Staff Publications

North American horned lizards of the genus Phrynosoma are largely myrmecophagous and squirt systemic blood from circumocular sinuses during encounters with certain mammalian predators. The predators react with distinct revulsion. Using bioassay-guided fractionation of blood plasma, we endeavored to identify the source and characteristics of the active chemical compound(s) responsible for this negative oral response. Our results of coyote bioassays and a series of novel mouse bioassay experiments were largely concordant. The active compound(s) was likely plasma-borne with a molecular weight (mw) of between 800 and 1,600. To identify the source of the active compound(s), we noted bioassay responses …

Eradication Of Feral Swine From A Barrier Island In Florida, Usa: An Examination Of Effort And Multi-Method, Multi-Species Population Indexing, Richard M. Engeman, Eric A. Tillman, Betsy A. Evans, John C. Griffin, Garrison Grobaski, Bradley S. Smith, John Stark, Bryan M. Kluever

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine (Sus scrofa) were targeted for and successfully eradicated from Saint Vincent Island (SVI), a National Wildlife Refuge (NWR) along the coast of Florida’s panhandle to protect its habitats and uncharacteristically high diversity of wildlife species for barrier islands in the region, including federal and state-listed threatened and endangered species. The eradication effort was initiated in early 2015 and concluded in 2019. A total of 438 feral swine were removed from the Island, 417 by federal control experts and 21 by recreational hunters. In general, the amount of effort needed to eradicate each feral swine slowly increased …

Downed Wood Removal Effects On Survival And Site Fidelity Of Woodrats In A California Oak Woodland, Timothy J. Smyser, Michael A. Hardy, Amy J. Davis, William L. Preston, William D. Tietje

United States Department of Agriculture Wildlife Services: Staff Publications

Owing to the increasing intensity and frequency of wildfires in the western United States, the removal of woody debris (downed dead wood and snags) from fire‐prone landscapes is being evaluated for wildfire mitigation. Consequently, the study of the ecological value of coarse woody debris to sustain dependent species has become of foremost importance. From 2004–2009, we used a before‐after control‐impact (BACI) study design to assess the effects of downed wood removal on a population of big‐eared woodrats (Neotoma macrotis) in an oak woodland (Quercus spp.) in coastal‐central California, USA. Using Pollock's robust design mark‐recapture analyses (with 12 …

High Thermal Quality Rookeries Facilitate High Thermoregulatory Accuracy In Pregnant Female Rattlesnakes, Haley A. Moniz, Jack Henry Buck, Hayley L. Crowell, Scott M. Goetz, Trevor D. Ruiz, Emily N. Taylor, Scott M. Bobacks

United States Department of Agriculture Wildlife Services: Staff Publications

Temperature is a primary factor influencing organismal development, and the fluctuating daily and seasonal thermal regimes of temperate climates may challenge the ability of viviparous reptiles to optimize body temperatures during gestation. Testing how viviparous reptiles navigate highly variable thermal conditions (e.g., relatively cold nights and/or highly fluctuating temperatures) is a powerful way to understand how they use microhabitats for thermoregulatory benefits. We assessed the thermal ecology of pregnant and non-pregnant female prairie rattlesnakes (Crotalus viridis) inhabiting a high-elevation, montane shrubland in northwest Colorado throughout their short summer active season, addressing the thermal consequences of microhabitat selection with …

Characterizing Feral Swine Movement Across The Contiguous United States Using Neural Networks And Genetic Data, Rachael M. Giglio, Courtney F. Bowden, Ryan K. Brook, Antoinette J. Piaggio, Timothy J. Smyser

United States Department of Agriculture Wildlife Services: Staff Publications

Globalization has led to the frequent movement of species out of their native habitat. Some of these species become highly invasive and capable of profoundly altering invaded ecosystems. Feral swine (Sus scrofa × domesticus) are recognized as being among the most destructive invasive species, with populations established on all continents except Antarctica. Within the United States (US), feral swine are responsible for extensive crop damage, the destruction of native ecosystems, and the spread of disease. Purposeful human-mediated movement of feral swine has contributed to their rapid range expansion over the past 30 years. Patterns of deliberate introduction of …

Bayesian Integrated Species Distribution Models For Hierarchical Resource Selection By A Soaring Bird, Ryo Ogawa, Guiming Wang, L. Wes Burger, Bronson Strickland, J. Brian Davis, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Migratory birds exhibit seasonal geographic range (hereafter, range) dynamics during the annual cycle. Few studies have examined how migratory birds select their habitats for range occupancy at the species level and space use at the individual level simultaneously. We hypothesized that environmental variables directly related to fitness components would affect the range occupancy probabilities of migrants, whereas environment variables related to movements and flights would affect the space use intensities of migrants. We built Bayesian integrated species distribution models (ISDMs) to evaluate the effects of climate conditions, wind conditions, and landcover compositions on the seasonal range dynamics of American white …

Raccoon Density Estimation From Camera Traps For Raccoon Rabies Management, Amy J. Davis, Wesley C. Dixon, Richard B. Chipman, Amy T. Gilbert, Jacob E. Hill, James C. Beasley, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

Density estimation for unmarked animals is particularly challenging, yet density estimates are often necessary for effective wildlife management. Raccoons (Procyon lotor) are the primary terrestrial wildlife reservoir for Lyssavirus rabies within the United States. The raccoon rabies variant (RRVV) is actively managed at landscape scales using oral rabies vaccination (ORV) within the eastern United States. To effectively manage RRVV, it is important to know the density of raccoons to appropriately scale the density of ORV baits distributed on the landscape. We compared methods to estimate raccoon densities from camera‐trap data versus more intensive capture‐mark‐recapture (CMR) estimates across 2 …

Exploring Ecological Drivers Of Evolution Of The Brain, Cognition, And Behavior, Meghan Korte

Biology Dissertations - Archive

Evolutionary theory proposes that increases in brain size confer cognitive and behavioral benefits that offset the expensive investment in brain tissue. However, few studies have examined the relationship between brain size, cognition, and behavior within species. The majority of research has focused on cross-species comparisons, thus there is a need for empirical research within species examining how contrasting ecological pressures select for cognitive and behavioral benefits and how these may evolve in tandem with changes in brain size. My dissertation addresses this gap by examining: 1) Whether selection on brain size is linked to improvements in cognitive ability; 2) How …

Demographics And Recruitment Patterns In A Reintroduced Population Of Alligator Snapping Turtles (Macrochelys Temminckii), Melisa P. Blasky

Graduate Theses/Dissertations

Reintroductions have increasingly become a useful tool for managing wildlife populations, but post-reintroduction studies to evaluate the success of these efforts are often lacking. In 2007, 265 Alligator Snapping Turtles (Macrochelys temminckii) were released into several semi-impounded wetlands in the Washita River drainage basin in southeastern Oklahoma, where surveys in the late 1990s suggested that the species was functionally extirpated. I conducted turtle trapping surveys using baited hoop nets to assess demographics and recruitment patterns in the population 11–12 years after the initial reintroduction. I estimated the age of juveniles by counting scute annuli and compared the data …

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, …

Landscape-Scale Epidemiological Dynamics Of Sars-Cov-2 In White-Tailed Deer, Joshua Hewitt, Grete Wilson-Henjum, Derek T. Collins, Timothy J. Linder, Julianna B. Lenoch, Jonathan D. Heale, Christopher A. Quintanal, Robert Pleszewski, Dillon S. Mcbride, Andrew S. Bowman, Jeffrey C. Chandler, Susan A. Shriner, Sarah N. Bevins, Dennis J. Kohler, Richard B. Chipman, Allen L. Gosser, David L. Bergman, Thomas J. Deliberto, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding pathogen emergence in new host species is fundamental for developing prevention and response plans for human and animal health. We leveraged a large-scale surveillance dataset coordinated by United States Department of Agriculture, Animal and Plant Health Inspection Service and State Natural Resources Agencies to quantify the outbreak dynamics of SARS-CoV-2 in North American white-tailed deer (Odocoileus virginianus; WTD) throughout its range in the United States. Local epidemics in WTD were well approximated by a single-outbreak peak followed by fade out. Outbreaks peaked early in the northeast and mid- Atlantic. Local effective reproduction ratios of SARS-CoV-2 were between …

What Is Known, Unknown, And Needed To Be Known About Damage Caused By Wild Pigs, Kurt C. Vercauteren, Kim M. Pepin, Seth M. Cook, Sophie Mckee, Abigail Pagels, Keely J. Kohen, Ingrid A. Messner, Michael P. Glow, Nathan P. Snow

United States Department of Agriculture Wildlife Services: Staff Publications

Damage assessments provide evidence for initiating and evaluating management programs that protect natural resources and human livelihoods against invasive species. Wild pigs (Sus scrofa) cause extensive damage in their native and non-native ranges, but the extent of current damage and efficacy of management of the damage (i.e., population control of wild pigs, exclusion fencing, etc.) remains poorly described. We conducted a systematic review of physical damage caused by wild pigs to summarize what is known and identify knowledge gaps for damage assessment. Wild pig damage assessments have been overwhelmingly qualitative (84% of studies) and measured differently across studies, …

Tracking Sero-Molecular Trends Of Swine Brucellosis In Hawai'i And The Central Pacific, Thi Hai Au La, Ian A. Mcmillan, Prashant Dahal, Andrew H. Burger, Mahdi Belcaid, Darrin M. Phelps, Samuel M. Goldstein, Vienna R. Brown, Michael H. Norris

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction

Brucellosis is a zoonotic disease of mammals caused by bacterial species of the Brucella genus. The reservoir for disease is typically mammals, with species of Brucella found infecting amphibians, bats, and marine mammals. Brucella spp. can pass directly to humans through contact with infected animals or their products. Brucella spp. can cause chronic debilitating infections in mammals, including humans, and is associated with spontaneous abortions in infected animals, causing reduced fecundity. In Hawai‘i, terrestrial species that could harbor Brucella spp. include swine, cattle, horses, and axis deer among others. The numerous feral swine in Hawai‘i are known to carry …