Ungulates

Posters

 
Movement Patterns of American Pronghorn Near Large-Scale Disturbance
Megan Osterhout, Kelley M Stewart, Cody Schroeder, brian wakeling
Pronghorn antelope (Antelocapra americana) are a native species in the Great Basin that occupy open habitats, such as sagebrush steppe and grasslands. Resource selection and movements of pronghorn are likely driven, in part, by water sources and open terrain that allows for escape from coursing predators. Large-scale mineral extraction such as open-pit mining, causes large-scale disturbance of landscapes occupied by pronghorn. The Cortez Mountains in the central region of Nevada are impacted by an active open pit mine located at the base of the mountain; an area used extensively by a resident population of pronghorn.  Our objective was to evaluate how open-pit gold mining affected movement patterns and selection of resources by pronghorn.  We captured 12 female pronghorn in the Cortez Range in January 2018.  Each animal was fitted with a Vectronic GPS collar that emitted six location points per day. 35,000 locations were recorded over two years, with an average distance from the mining boundary of 4,653 meters and 42% of the locations fall within the boundary. Pronghorn do not appear to avoid habitat near the mine, suggesting they may have adapted to living in a high-disturbance environment.
 
Exploring Auditory Thresholds for Reindeer, Rangifer Tarandus
Megan Perra, Todd Brinkman, Sarah Barcalow, Peter Scheifele
Current and proposed human development throughout high northern latitudes must assess and try to mitigate impacts on caribou and reindeer (Rangifer tarandus) herds. Sound created by development can be far-reaching, and determining the potential impacts of noise on wildlife can inform landscape use. To advance our understanding of Rangifer’s potential response to anthropogenic noise, we must first understand what they can hear. Using domestic reindeer from the Large Animal Research Station (LARS) at the University of Alaska Fairbanks, we performed a Brainstem Auditory Evoked Response to estimate auditory thresholds of the species.  We assessed the central auditory response and tested the sensitivity in six female reindeer of various ages.  Prior to our work, the lowest audible frequency for the species was reported to be 63 Hz in previous studies.  We identified auditory threshold lower limit of 30 Hz in our study subjects and quantified reindeer sensitivity thresholds (dB peSPL) to frequencies ranging from 30-16,000 Hz.  Our results indicate that anthropogenic sounds previously thought to be beyond the hearing range of Rangifer—such as seismic exploration—are likely to be audible to the species, and therefore have the potential to affect their soundscape.  We compare our findings on Rangifer hearing with new measurements of anthropogenic sounds recorded on passive acoustic monitors distributed throughout northern Alaska, as well as biological sounds produced by the Rangifer themselves (e.g., vocalizations and sesamoid clicks produced by the ankles).  All classes of anthropogenic sound fall within the threshold range that we identified for Rangifer.  Our findings have important implications for the assessment of environmental impacts within Rangifer range and will inform future soundscape ecology research.  
 
Movements and Resource Selection of Wild Pigs in Relation to Crop Growth Stages
Humberto Perotto-Baldivieso, Kurt VerCauteren, Nathan Snow, Michael Cherry, Bethany Friesenhahn, Randy W. DeYoung
Wild pigs (Sus scrofa) are an invasive species first introduced to North America in the 1500s. Due to their high reproductive rate and omnivorous diet, populations of wild pigs present an increasing management challenge throughout much of North America. Wild pigs annually cause billions of dollars in damage to agriculture in the USA, with the most severe damage reported to corn. Our objective was to quantify movements, space use, and resource selection of wild pigs in an agricultural landscape in relation to growth stages of corn. We monitored hourly movements of adult wild pigs using GPS collars (n = 34 in 2019 and n = 34 in 2020) during the growing season (Feb–Sept) in Delta County, Texas, USA. We conducted separate analyses during the pre-planting, establishment, vegetative, blister/milk, and dent/mature growth stages of corn. We generated home ranges using the dynamic Brownian Bridge movement model and calculated home range centroid distance to nearest corn field.  We then conducted step selection functions to quantify selection during each growth stage. We found that mean centroid distance to corn was closest during the blister/milk stage and farthest away in the vegetative stage, when the plant provides no nutritional value to pigs. Wild pigs consistently selected for corn fields during the blister and mature stages but displayed no preference or avoidance during earlier growth stages. Our results indicate that pig damage is sustained to corn during latter growth stages.  Because pigs changed space use during the growing season, management efforts timed before the milk stage would be best to protect agricultural resources. Our study provides a better understanding of wild pig spatial ecology and can inform management strategies aimed at the alleviation of crop damage. 
 
Temporal and Spatial Distribution of Ticks Collected from Feral Swine in Northern and Central Florida, and Implications for Tick-Borne Disease Surveillance – SRIP
Sarah Mays Maestas, Lindsay Campbell, Michael Milleson, Phillip Kaufman, Samantha Wisely
Vector-borne pathogen surveillance reveals information about the presence, prevalence, and distribution of vectors and pathogens that can aid in outbreak prediction and prevention efforts. Feral swine are distributed across much of the United States, and are hosts to multiple tick species associated with human disease. Due to the environmental damage caused by feral swine, control measures are regularly undertaken by state and federal agencies and private landowners. The purpose of this project was to collect ticks from feral swine during routine control measures as a method of tick-borne disease surveillance. Adult ticks were collected from 137 adult feral swine in 21 northern and central Florida counties from August of 2019 through September of 2020 by USDA Wildlife Services personnel and submitted to the University of Florida Veterinary Entomology Laboratory. A total of 1,268 adult ticks were collected: 1,001 Amblyomma americanum, 32 A. maculatum, 132 Dermacentor variabilis, 69 Ixodes scapularis, and 34 damaged specimens identified as Ixodes sp. The diversity of tick species collected from feral swine is comparable to collections made throughout the state with conventional surveillance methods such as dragging and flagging, and all tick species collected have implications for pathogen transmission to humans and other animals. These results suggest that tick collection from feral swine is a suitable means of surveillance for potential pathogen vectors. Further spatiotemporal analyses of tick distributions in relation to landscape variables as well as pathogen screening of collected ticks will contribute additional information toward tick-borne disease surveillance. The results of this study will provide useful information about the suitability of tick collection from feral swine as a method of tick-borne disease surveillance, and about the distribution of ticks and tick-borne pathogens in the state to better understand the implications for human and animal health.  
 
Spatiotemporal Activity Overlap between Invasive Wild Pigs and Other Wildlife on Private Land in South Carolina – SRIP
Elizabeth Saldo, Alex Jensen, Mike Muthersbaugh, Jay Butfiloski, Jay Cantrell, John Kilgo, Charles Ruth, David Jachowski
Biological invasions are a burgeoning concern due to the suite of impacts they have on ecosystems, communities, and species. The wild pig (Sus scrofa) has considerably expanded its range, achieving a global distribution. By consuming shared foods or destroying vegetation by rooting, wild pigs indirectly compete with other species through resource exploitation, while interference competition, such as wild pig aggression, might further reduce the ability of other animals to obtain resources. Supplemental feeding of deer for hunting, which is prevalent on private lands in South Carolina, could exacerbate such competitive interactions while also expediting the spread of wild pigs, increasing prey exposure to predators, facilitating disease transmission, and lowering hunting success. Our objectives were to (1) examine patterns of spatiotemporal overlap between wild pigs and other wildlife and (2) use a field experiment to investigate wild pig, white-tailed deer (Odocoileus virginianus), and coyote (Canis latrans) spatiotemporal activity responses to supplemental feeding. We deployed 93 unbaited wildlife cameras (spring 2019-summer 2021) in a grid and 15 baited cameras (spring-summer 2021) in a stratified random design across our study area. As of April 2021, unbaited cameras captured over 2.5 million photographs, 318,644 of which were classified to species. Preliminary analyses of temporal overlap between wild pigs and deer, eastern gray squirrel (Sciurus carolinensis), and eastern wild turkey (Meleagris gallopavo) showed lower overlap in fall than spring for all three wild pig and native mast consumer pairings. Future analyses will compare activity at unbaited and baited cameras, thus providing further insight into wild pig competition with other species. We also GPS-collared 24 coyotes and 23 female deer in winter 2021, implanting the latter with birthing transmitters to assist with fawn GPS-collaring. Data from collars will be used to examine deer and coyote space use in relation to supplemental feeding and wild pig activity.
 
Genetic Breed Association of the Feral Horses of Theodore Roosevelt National Park – SRIP
Melissa Thompson
Theodore Roosevelt National Park is home to a wide variety of large ungulate species, including a herd of feral horses (Equus caballus). The free-roaming horses were present on the landscape prior to 1956, when the park perimeter was fenced and the population was closed in. The herd is now maintained for education of the public as a cultural demonstration herd, representative of the livestock seen in the 1880s when Theodore Roosevelt was ranching in the area. Management of the feral horses takes more time and energy than any other species in the park, due to their rapid population growth and the politically charged atmosphere around the subject of their welfare. The origin and genetic health of the herd is a contentious topic in considering management strategies. I am using a genome-wide approach to compare these horses to established horse breeds and help clarify the origins of the herd. Hair or tissue samples were collected from 118 park horses and genotyped using the Illumina Equine 70k BeadChip. These genotypes were then compared with a publicly available dataset of horses from thirty-five different breeds. I am using principal components analysis (PCA), Bayesian clustering analysis, and tree-based methods to examine the genetic population structure of the combined dataset. Preliminary results of Bayesian clustering analysis show the park horses clustering into their own population distinct from other breeds (K=10), likely due to isolation and repeated bottleneck events. On a PCA plot, the park horses fall nearest to some American, Swiss, and Spanish breeds. Evidence for population structure within the park itself is also present. This study will aid the park’s management team in the creation of their new Horse Management Plan. Genetic breed association and ancestry information will help resolve the speculation surrounding the origins of the herd and inform conservation priority.
 
Investigating the Role of Climate Change in An Expanding Moose Population in Southwest Alaska – SRIP
Sebastian Zavoico, Shawn Crimmins, Joe Eisaguirre, Andy Aderman, Graham Frye, Mark Lindberg
Climate change is altering the ecosystem structure across the Arctic and sub-Arctic. One of the fastest-changing regions is southwest Alaska, where a combination of shrubification, decreasing winter sea-ice concentration, and increasingly inconsistent winter snowpack have already dramatically changed the area ecology. Another potential result – and, in turn, driving force – of this change is the rapid colonization of moose (Alces alces gigas) across the region into areas in which moose intermittently inhabited, and then only in low densities. This study’s main objective is to directly link the expanding moose population with the changing landscape, and aims to meet this objective by including various environmental covariates into an Integrated Population Model (IPM) that brings together long-term telemetry and count data into one model. The IPM will thus correlate covariates with estimated survival parameters, population counts, and emigration dynamics. Environmental covariates to be incorporated into the IPM include vegetation productivity, shrub cover change, and a winter severity index, which will be collected using various remote sensing techniques. If climate change has an impact on the moose colonization, increasing shrub productivity and decreasing snowpack should both be correlated with higher survival and population, and moose should be emigrating into areas undergoing the greatest rates of shrub cover and productivity increase.
 
Movements, Genetics, and Early Detection: A Three-Pronged Approach to Effective Wild Pig Management in a Bottomland and Upland Forested Landscape – SRIP
Tyler Evans, Melanie Boudreau, Bronson Strickland, Garrett Street, Raymond Iglay
Wild pigs (Sus scrofa) have been in the southeastern United States for centuries. However, invasions into previously uninhabited areas still occur and present novel opportunities to investigate wild pig activities to improve detection, monitoring, and rapid response actions. The Sam D. Hamilton Noxubee National Wildlife Refuge (hereafter Noxubee NWR) has an emerging wild pig invasion beginning to noticeably impact other wildlife resources in bottomland and upland forests. Our objectives are to 1) identify landscape and temperature influences on wild pig movement, space use, and behavior in relation to time of day and season; 2) design and implement non-invasive genetic sampling for wild pigs to estimate abundance; and 3) implement and evaluate a rapid assessment tool for detecting and mapping wild pig activity. Movement, space use, and behavior will be investigated at coarse (e.g., home range) and fine (e.g., location-specific behaviors) scales using GPS collars, accelerometers, and magnetometers on adult sows (n = 10) to understand how sounders use the forested landscape (e.g., foraging hotspots). For genetic sampling, a non-grain attractant that maximizes wild pig visitation will be used to bait hair snares (n > 4) to collect DNA samples for amplification, genotyping, and analysis in a capture-recapture framework to determine wild pig abundance. Finally, 20-m x 500-m line transects (n = 184) will be distributed across Noxubee NWR and serve as a census of wild pig activity (i.e., wallowing and rooting areas along and between transects). Using the census as a baseline representation of activity, sub-sampling approaches will be simulated and field-validated to determine if sub-sampling can be used as a rapid assessment tool for future monitoring efforts. Our findings will be used to better inform wild pig management on Noxubee NWR and other bottomland and upland forested landscapes experiencing wild pig invasions in the southeastern United States.
 
The Effects of Hunting on the Iconic Plains Bison: Insights from Captive Populations – SRIP
Katherine Jamer, Ronald Sarno, Melissa Grigione
The American bison (Bison bison) has become a flagship species for conservation due to its successful recovery. However, the species is still at risk.  Habitat contraction and disease transmission to livestock have resulted in a loss of large-scale movements and panmixia, resulting in isolated populations containing contracted gene pools. Historically sought for their meat and hide, bison were overhunted during the western expansion of the United States. Bison are still subject to extensive hunting, causing major effects on age structure, sex ratios, and land use. Furthermore, changes in male mating behavior associated with hunting could reduce genetic diversity by altering mating dynamics, because reproductive success of bull bison is determined by their ability to maintain dominance through bellowing and fighting. Animal behavior can be altered when exposed to a stressor such as hunting. Responses to stress can be studied using fecal hormone analysis. Therefore, our objective is to investigate the relationship between human hunting of bison and fecal corticosterone levels in bison. Corticosterone is a hormone commonly studied to identify stress and is linked to behavior changes. Fecal samples from free-ranging hunted and non-hunted populations of bison will be collected and analyzed. Samples will also be collected from captive populations of bison to use as a baseline for corticosterone levels in the absence of hunting. We hypothesize that bison will have higher levels of corticosterone in populations exposed to hunting. Results of this study will provide insight into the effects hunting has on bison populations.
 
The Past Is the Key to the Present: The Paleoecology of Bison From High Elevation Ice Patches in the Greater Yellowstone Ecosystem, and Implications for Modern Bison Conservation – SRIP
Darian Bouvier
Modern American bison (Bison bison) of the Yellowstone area are iconic and well-studied. However, it is unclear how the ecology and behavior of these herds have evolved through time in response to changes in climate, land use, and human disruption. Pre-bottleneck records of bison behavior and land-use are rare and the historical records that do exist, arguably, reflect a bison population that was under stress and may not represent ‘typical’ behaviors. Analyses of preserved bison keratinous horn sheaths recovered from melting ice patches in high-elevation areas of the Greybull River Basin have the potential to address key questions surrounding historical variability in the ecology and behavior of bison populations in the region.  Bison behavior is determined by intrinsic factors such as age and sex, as well as extrinsic factors such as local forage conditions. To monitor intrinsic factors, thin sections were taken to view keratinous layers under microscopic imaging. Examination and imaging exhibit incremental growth of bison horn sheath through time as these annually produced layers are stacked. Extrinsic factors were reconstructed using a MaxEnt model which displays a prediction distribution with increasing dispersal in the Rocky Mountain front range. This model additionally displays localities that support the common occurrence of bison in high elevation areas.  Stable isotopes from prehistoric bison horn sheaths will also be used to reconstruct animal diet and movement patterns during the period of growth. I will examine the seasonally resolved records of these animals’ life history through analyses of multiple stable isotope systems in horn sheath keratin. Carbon (δ13C), oxygen (δ18O), and nitrogen (δ15N) isotopes will be used to examine dietary, migratory, and local climatic patterns of these Bison bison specimens.

Posters
Location: Virtual Date: November 4, 2021 Time: 11:00 am - 12:00 pm