Animal Sciences Commons^™

Short Term Safety, Immunogenicity, And Reproductive Effects Of Combined Vaccination With Anti-Gnrh (Gonacon) And Rabies Vaccines In Female Feral Cats, Shiri Novak, Boris Yakobson, Shir Sorek, Liat Morgan, Smadar Tal, Ran Nivy, Roni King, Lauren Jaebker, Douglas C. Eckery, Tal Raz

United States Department of Agriculture Wildlife Services: Staff Publications

Overpopulation of free-roaming cats is a major problem leading to negative impacts on animal health and welfare, public nuisance, transmission of zoonotic diseases, and well-documented harm to wildlife. Surgical sterilization had failed to provide a practical solution to free-roaming cats’ overpopulation under field conditions; therefore, efficient and safe non-surgical immunocontraception methods are aspired. Rabies is a deadly virus that may infect people and animals. However, the safety and efficacy of combined vaccination with anti-GnRH and rabies vaccines in feral cats, which often suffer from disrupted health conditions and experienced high stress level, has never been studied. Therefore, our objective was …

Smallmouth Bass Feeding Dynamics And Growth In Headwater Streams Of The Interior Highlands, Brandon C. Plunkett

ATU Theses and Dissertations 2021 - Present

Smallmouth Bass have been extensively studied, but knowledge of the effects of temperature and hydrologic regime on populations in the Interior Highlands of Arkansas remains lacking. In 2018, I monitored diet characteristics of Smallmouth Bass, located in streams prone to dryness and representing a range of water temperatures, and presence of potential competitors. Diet characteristics of Smallmouth Bass, Green Sunfish, and Creek Chub were studied in the Boston Mountains ecoregion of Arkansas during the summer of 2018. In 2019, I expanded the scope of the project to search for relationships between Smallmouth Bass growth and hydrologic regime. My objectives were …

Climate-Driven Impacts On Himalayan Aquatic Biodiversity: A Case Study Involving Snowtrout (Cyprinidae: Schizothorax), Riri Wiyanti Retnaningtyas

Graduate Theses and Dissertations

Monitoring biodiversity, to include its relative dispersal and contraction, has become a conservation task of great importance, particularly given the catastrophic and ongoing loss of habitat due to climate change. However, the timing, direction, and magnitude of these rates vary across taxa and ecosystems. Predicting specific impacts of climate change can thus be difficult and this, in turn, hampers management action. Metrics are needed to not only quantify contemporary requirements of species, but also predict potential distributions that fluctuate in lockstep with climate.

Montane ecosystems in the Himalayas are highly impacted by climate change, yet remain largely understudied due to …

Population Genomics Of Invasive Rodents On Islands: Genetic Consequences Of Colonization And Prospects For Localized Synthetic Gene Drive, Kevin P. Oh, Aaron B. Shiels, Laura Shiels, Dimitri V. Blondel, Karl J. Campbell, J. Royden Saah, Alun L. Lloyd, Paul Q. Thomas, Fred Gould, Zaid Abdo, John R. Godwin, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Introduced rodent populations pose significant threats worldwide, with particularly severe impacts on islands. Advancements in genome editing have motivated interest in synthetic gene drives that could potentially provide efficient and localized suppression of invasive rodent populations. Application of such technologies will require rigorous population genomic surveys to evaluate population connectivity, taxonomic identification, and to inform design of gene drive localization mechanisms. One proposed approach leverages the predicted shifts in genetic variation that accompany island colonization, wherein founder effects, genetic drift, and island-specific selection are expected to result in locally fixed alleles (LFA) that are variable in neighboring nontarget populations. Engineering …

Impact Of Whitetail Deer Overpopulation With Hunting On The Decline, Matthew J. Lamprinos

English Department: Research for Change - Wicked Problems in Our World

The whitetail deer is a key species for Pennsylvania’s forests, but their ecological balance has been disturbed by unregulated growth and urban sprawl. The deer population in Pennsylvania has exploded since the 1880’s causing a wide range of damage on the ecosystem, and humans. To reduce deer populations to sustainable levels, the Pennsylvania Game Commission relies heavily on hunters to dedicate time in the fall to go out and fill the tags the they issue. Hunter participation all around the world is decreasing for a variety of reasons. Fewer hunters out in the field causes revenue losses for the Game …

Using Enclosed Y-Mazes To Assess Chemosensory Behavior In Reptiles, M. Rockwell Parker, Andrea F. Currylow, Eric A. Tillman, Charlotte J. Robinson, Jilian M. Josimovich, Isabella M.G. Bukovich, Lauren A. Nazarian, Melia G. Nafus, Bryan M. Kluever, Amy A. Yackel Adams

United States Department of Agriculture Wildlife Services: Staff Publications

Reptiles utilize a variety of environmental cues to inform and drive animal behavior such as chemical scent trails produced by food or conspecifics. Decrypting the scent-trailing behavior of vertebrates, particularly invasive species, enables the discovery of cues that induce exploratory behavior and can aid in the development of valuable basic and applied biological tools. However, pinpointing behaviors dominantly driven by chemical cues versus other competing environmental cues can be challenging. Y-mazes are common tools used in animal behavior research that allow quantification of vertebrate chemosensory behavior across a range of taxa. By reducing external stimuli, Y-mazes remove confounding factors and …

Unprecedented Migratory Bird Die-Off: A Citizen-Based Analysis On The Spatiotemporal Patterns Of Mass Mortality Events In The Western United States, Di Yang, Anni Yang, Jue Yang, Rongting Xu, Han Qiu

United States Department of Agriculture Wildlife Services: Staff Publications

Extensive, severe wildfires, and wildfire-induced smoke occurred across the western and central United States since August 2020. Wildfires resulting in the loss of habitats and emission of particulate matter and volatile organic compounds pose serious threatens to wildlife and human populations, especially for avian species, the respiratory system of which are sensitive to air pollutions. At the same time, the extreme weather (e.g., snowstorms) in late summer may also impact bird migration by cutting off their food supply and promoting their migration before they were physiologically ready. In this study, we investigated the environmental drivers of massive bird die-offs by …

Resource Assessment Report Abrolhos Islands And Mid-West Trawl Managed Fishery Resource, Mervi Kangas, A Chandrapavan, Anne Wilkins, E. A. Fisher, S. Evans

WA Marine Stewardship Council report series

This document provides a cumulative description and assessment of the Abrolhos Islands and Mid-West Trawl Managed Fishery (AIMWTMF) and all of the fishing activities (i.e. fisheries / fishing sectors) affecting this resource in Western Australia (WA). This resource comprises of a single species of scallop, Ylistrum balloti which occurs in inshore waters to around 40 m depth at the Abrolhos Islands. This species is captured exclusively by demersal otter trawl gear in the West Coast Bioregion.

Toxicity Of Sodium Nitrite-Based Vertebrate Pesticides For European Starlings (Sturnus Vulgaris), Scott J. Werner, Shelagh T. Deliberto, Hailey E. Mclean, Katherine E. Horak, Kirt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

In the 21st century, invasive animals rank second only to habitat destruction as the greatest threat to global biodiversity. Socially-acceptable and cost-effective strategies are needed to reduce the negative economic and environmental impacts of invasive animals. We investigated the potential for sodium nitrite (SN; CAS 7632-00-0) to serve as an avian toxicant for European starlings (Sturnus vulgaris L.). We also assessed the non-target hazard of an experimental formulation of SN that is being developed as a toxicant for invasive wild pigs (Sus scrofa L.). In gavage experiments with European starlings, we identified a lowest observed adverse effect level …

Sars-Cov-2 Exposure In Escaped Mink, Utah, Usa, Susan A. Shriner, Jeremy W. Ellis, J. Jeffrey Root, Annette Roug, Scott R. Stopak, Gerald W. Wiscomb, Jared R. Zierenberg, Hon S. Ip, Mia Kim Torchetti, Thomas J. Deliberto

United States Department of Agriculture Wildlife Services: Staff Publications

In August 2020, outbreaks of coronavirus disease were confirmed on mink farms in Utah, USA. We surveyed mammals captured on and around farms for evidence of infection or exposure. Free-ranging mink, presumed domestic escapees, exhibited high antibody titers, suggesting a potential severe acute respiratory syndrome coronavirus 2 transmission pathway to native wildlife.

We report a wildlife epidemiologic investigation of mammals captured on or near properties in Utah, USA, where outbreaks of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection occurred in farmed mink. Mink farms are relatively common in the United States, and most are small family farms. The US …

Great Expectations: Deconstructing The Process Pathways Underlying Beaver-Related Restoration, Caroline S. Nash, Gordon E. Grant, Susan Charnley, Jason B. Dunham, Hannah Gosnell, Mark B. Hausner, David S. Pilliod, Jimmy Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Beaver-related restoration is a process-based strategy that seeks to address wide-ranging ecological objectives by reestablishing dam building in degraded stream systems. Although the beaver-related restoration has broad appeal, especially in water-limited systems, its effectiveness is not yet well documented. In this article, we present a process-expectation framework that links beaver-related restoration tactics to commonly expected outcomes by identifying the set of process pathways that must occur to achieve those expected outcomes. We explore the contingency implicit within this framework using social and biophysical data from project and research sites. This analysis reveals that outcomes are often predicated on complex process …

Avian Visual Ecologists Should Consider Uv Absorbance And All Sensory Modalities: A Response To Wisenden Et Al. (2020), Sean T. O'Daniels, Scott J. Werner, Ken Yasukawa

United States Department of Agriculture Wildlife Services: Staff Publications

In a recent publication, Wisenden et al. (2020) examined responses of territorial male Red-winged Blackbirds (Agelaius phoeniceus) to models constructed with ultraviolet (UV)-reflective red epaulets for the purpose of determining if the addition of UV reflectance to epaulets ("UV+") changed the effectiveness of signals to receivers relative to "control" epaulets under field conditions. The authors hypothesized that "UV+epaulet coloration represents a visual signal with increased efficacy in territorial interactions." They presented behavioral data but no visual modeling data. Our aims in this commentary are to suggest alternative terms to those used by the authors, to express concern about the use …

Factors Leading To Successful Island Rodent Eradications Following Initial Failure, Araceli Samaniego, Peter Kappes, Keith Broome, Steve Cranwell, Richard Griffiths, Grant Harper, Pete Mcclelland, Russell Palmer, Gerard Rocamora, Keith Springer, David Will, Shane Siers

United States Department of Agriculture Wildlife Services: Staff Publications

Island rodent eradications are increasingly conducted to eliminate the negative impacts of invasive rodents. The success rate in the tropics has been lower than in temperate regions, triggering research and reviews. Environmental factors unique to the tropics (e.g., land crabs and year-round rodent breeding) have been associated with eradication failure. Operational factors have also been important, but these have not been comprehensively assessed. The environmental and operational factors using global cases where rodent eradication initially failed and subsequent attempts occurred were compared. It was determined whether operational factors explained the initial failures, whether operational improvements explained subsequent successes, and whether …

Production Of Embryos And A Live Offspring Using Post Mortem Reproductive Material From Bison (Bison Bison Bison) Originating In Yellowstone National Park, Usa, Hayley M. Benham, Matthew P. Mccollum, Pauline Nol, Rebecca K. Frey, P. Ryan Clarke, Jack C. Rhyan, Jennifer P. Barfield

United States Department of Agriculture Wildlife Services: Staff Publications

Bison from Yellowstone National Park (YNP) have an important genetic history. As one of the few wild herds of bison with no evidence of cattle DNA introgression and a large enough population to maintain genetic diversity, they are considered a conservation priority for the species. Unfortunately, there is a high prevalence of the zoonotic disease brucellosis in the herd. Part of the management strategy for controlling the disease and herd size in YNP is to remove bison from the population during the winter migration out of the park. This interagency management cull provides an opportunity to collect a large number …

Dispersal And Land Cover Contribute To Pseudorabies Virus Exposure In Invasive Wild Pigs, Felipe A. Hernandez, Amanda N. Carr, Michael P. Milleson, Hunter R. Merrill, Michael L. Avery, Brandon M. Parker, Cortney L. Pylant, James D. Austin, Samantha M. Wisely

United States Department of Agriculture Wildlife Services: Staff Publications

We investigated the landscape epidemiology of a globally distributed mammal, the wild pig (Sus scrofa), in Florida (U.S.), where it is considered an invasive species and reservoir to pathogens that impact the health of people, domestic animals, and wildlife. Specifically, we tested the hypothesis that two commonly cited factors in disease transmission, connectivity among populations and abundant resources, would increase the likelihood of exposure to both pseudorabies virus (PrV) and Brucella spp. (bacterial agent of brucellosis) in wild pigs across the Kissimmee Valley of Florida. Using DNA from 348 wild pigs and sera from 320 individuals at 24 sites, we …

Temporal Invariance Of Social-Ecological Catchments, Mark A. Kaemingk, Christine N. Bender, Chris Chizinski, Aaron J. Bunch, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Natural resources such as waterbodies, public parks, and wildlife refuges attract people from varying distances on the landscape, creating “social-ecological catchments.” Catchments have provided great utility for understanding physical and social relationships within specific disciplines. Yet, catchments are rarely used across disciplines, such as its application to understand complex spatiotemporal dynamics between mobile human users and patchily distributed natural resources. We collected residence ZIP codes from 19,983 angler parties during 2014–2017 to construct seven angler–waterbody catchments in Nebraska, USA. We predicted that sizes of dense (10% utilization distribution) and dispersed (95% utilization distribution) angler–waterbody catchments would change across seasons and …

Roost Use And Movements Of Northern Long-Eared Bats In A Southeast Nebraska Agricultural Landscape, Christopher Fill, Craig R. Allen, John F. Benson, Dirac Twidwell

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Bats are important bio-indicators of ecosystem health and provide a number of ecosystem services. White-nose Syndrome and habitat loss have led to the decline of many bat species in eastern North America, including the federally threatened northern long-eared bat, Myotis septentrionalis. White-nose Syndrome was only recently found in Nebraska, which lies on the western extent of this species geographic range. To better understand how this forest-dependent species persists in an agriculturally dominated landscape amid a growing number of pressures, we investigated the roosting habits of this bat at the Homestead National Monument of America, located in southeast Nebraska. We …

Phylogenomics Reveals Ancient And Contemporary Gene Flow Contributing To The Evolutionary History Of Sea Ducks (Tribe Mergini), Philip Lavretsky, Robert E. Wilson, Sandra L. Talbot, Sarah A. Sonsthagen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Insight into complex evolutionary histories continues to build through broad comparative phylogenomic and population genomic studies. In particular, there is a need to understand the extent and scale that gene flow contributes to standing genomic diversity and the role introgression has played in evolutionary processes such as hybrid speciation. Here, we investigate the evolutionary history of the Mergini tribe (sea ducks) by coupling multi-species comparisons with phylogenomic analyses of thousands of nuclear ddRAD-seq loci, including Z-sex chromosome and autosomal linked loci, and the mitogenome assayed across all extant sea duck species in North America. All sea duck species are strongly …

No Ape Left Behind: Orangutan Conservation Education Project, Danna Boshak

All Graduate Projects

Orangutans are critically endangered and if action is not taken, their extinction is imminent. Zoological institutions worldwide serve as an educational means to engage the broader public in conservation awareness and action behaviors. The Association of Zoos and Aquariums (AZA) created the Saving Animals From Extinction (SAFE) initiative to provide zoos with a platform to expand conservation efforts beyond their institutions. In collaboration with the Orangutan SAFE (OSAFE) education committee, the No Ape Left Behind: Orangutan Conservation Education Project develops educational activity resources that provide information about orangutan behavior and ecology as well as action items that individuals can take …

Impacts Of Extreme Environmental Disturbances On Piping Plover Survival Are Partially Moderated By Migratory Connectivity, Kristen S. Ellis, Michael J. Anteau, Francesca J. Cuthbert, Cheri L. Gratto-Trevor, Joel G. Jorgensen, David J. Newstead, Larkin Powell, Megan M. Ring, Mark H. Sherfy, Rose J. Swift, Dustin L. Toy, David N. Koons

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Effective conservation for listed migratory species requires an understanding of how drivers of population decline vary spatially and temporally, as well as knowledge of range-wide connectivity between breeding and nonbreeding areas. Environmental conditions distant from breeding areas can have lasting effects on the demography of migratory species, yet these consequences are often the least understood. Our objectives were to 1) evaluate associations between survival and extreme environmental disturbances at nonbreeding areas, including hurricanes, harmful algal blooms, and oil spills, and 2) estimate migratory connectivity between breeding and nonbreeding areas of midcontinental piping plovers (Charadrius melodus). We used capture …

Factors Influencing Aquatic Invertebrate Diversity In Mine Pit Lakes Along The Mesabi Iron Range, Jeremy Laurich

Journal of Earth and Life Science

Restoration of mine pit lakes for recreation is going to be very important for the future of Minnesota’s Mesabi Iron Range area. As many as 250 lakes will need to be restored in the future along this 100-kilometer-long swath of mining country. Information regarding the organisms that currently inhabit these lakes is important for future restorations to be a success. The focus of this study was to identify the types of aquatic invertebrates present in pit lakes and to identify some of the factors that influence their abundance and diversity. During this study, invertebrate samples were taken along the shore …

Potential Solar Replacement Of Hydroelectricity To Reopen Rivers: Maine As A Case Example, Shailesh Sharma, John Waldman

Publications and Research

Hydroelectricity provides 6% of U.S. electrical power needs, but hydro-dams also cause environmental harm, including the retardation or complete blockage of spawning runs of anadromous fishes. To facilitate fish movements, engineered-fishways have long been used but many have performed poorly. Dam-removal is the most effective way of restoring dwindling migratory fish populations by allowing unrestricted pathways to their spawning areas and for the downstream migrations of post-spawning adults and juveniles. However, removals of hydro-dams result in a loss of electricity production. For the replacement of energy foregone from hydro-dam removals, various alternative energy installations are now feasible. We present one-to-one …

Soil Response Of Helicopter Liming In The Monongahela National Forest, Jarrett Douglas Fowler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Soils in the Monongahela National Forest (MNF) are acidic due to sandstone parent material, acid deposition, uptake of base cations by vegetation, and release of organic acids by organic matter (OM) decomposition. Increases in soil acidity have caused declines in forest health and changed species composition and nutrient status. Liming can neutralize soil acidity, but no large-scale liming projects have been done on acid forest soils in the USA. In anticipation of acquiring funding for a proposed liming project in the MNF, in 2007 and 2009 10 sites were selected to sample and analyze soils before lime was applied. In …

Surveys For Ticks On Wildlife Hosts And In The Environment At Asian Longhorned Tick (Haemaphysalis Longicornis)-Positive Sites In Virginia And New Jersey, 2018, Seth A. White, Sarah N. Bevins, Mark G. Ruder, David Shaw, Stacey L. Vigil, Adam Randall, Thomas J. Deliberto, Kristen Dominguez, Alec T. Thompson, James W. Mertins, Jeffrey T. Alfred, Michael J. Yabsley

United States Department of Agriculture Wildlife Services: Staff Publications

Haemaphysalis longicornis, the Asian longhorned tick (ALT), is native to eastern Asia, but it has become invasive in several countries, including Australia, New Zealand and recently in the eastern United States (US). To identify wild mammal and avian host species in the US, we conducted active wildlife surveillance in two states with known ALT infestations (Virginia and New Jersey). In addition, we conducted environmental surveys in both states. These surveillance efforts resulted in detection of 51 ALTinfested individuals from seven wildlife species, including raccoon (Procyon lotor), Virginia opossum (Didelphis virginiana), red fox (Vulpes vulpes …

Estimating Wildlife Strike Costs At Us Airports: A Machine Learning Approach, Levi Altringer, Jordan Navin, Michael J. Begier, Stephanie A. Shwiff, Aaron M. Anderson

United States Department of Agriculture Wildlife Services: Staff Publications

Current lower bound estimates of the economic burden of wildlife strikes make use of mean cost assignment to impute missing values in the National Wildlife Strike Database (NWSD). The accuracy of these estimates, however, are undermined by the skewed nature of reported cost data and fail to account for differences in observed strike characteristics—e.g., type of aircraft, size of aircraft, type of damage, size of animal struck, etc. This paper makes use of modern machine learning techniques to provide a more accurate measure of the strike-related costs that accrue to the US civil aviation industry. We estimate that wildlife strikes …

First Record Of Blacknape Large-Eye Bream Gymnocranius Satoi (Perciformes: Lethrinidae) In The Philippines, Nicko Amor Flores, Jade Tifany Rey, Jeffrey T. Williams, Kent Carpenter, Mudjekeewis Santos

Biological Sciences Faculty Publications

The Philippines has been regarded as the center of the center of marine shorefish biodiversity, having the highest number of fish species per square area in the world. The blacknape large-eye bream, Gymnocranius satoi, has been reported to occur from Southern Japan, Taiwan to Northwestern Australia and to the Coral Sea, but has not previously been recorded from the Philippines. From 2011 – 2019, the National Fisheries Research and Development Institute (NFRDI) collaborated with the National Museum of Natural History of the Smithsonian Institution (NMNH/SI), USA, and the Old Dominion University (ODU), Virgina, USA, to inventory all commercial fish …

Effects Of Large Wood Restoration On Coho Salmon In A Northern California Watershed: A Before-After-Control-Impact Experiment, Natalie B. Okun

Cal Poly Humboldt theses and projects

Substantial time, money, and effort are invested in river and stream restoration projects to aid in the recovery of imperiled salmonid populations, but there is little evidence that these efforts have had lasting positive impacts on juvenile fish growth and survival. To assess the effectiveness of large woody debris (LWD) restoration, which is one of the most common restoration practices, I evaluated the growth and survival response of endangered Central California Coast coho salmon (Oncorhynchus kisutch) in a paired watershed before-after impact-control (BACI) study. To determine if LWD supplementation influenced coho salmon growth and survival, two neighboring, similar …

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 …

Evidence On The Effectiveness Of Small Unmanned Aircraft Systems (Suas) As A Survey Tool For North American Terrestrial, Vertebrate Animals: A Systematic Map Protocol, Jared A. Elmore, Michael F. Curran, Kristine O. Evans, Sathishkumar Samiappan, Meilun Zhou, Morgan B. Pfeiffer, Bradley F. Blackwell, Raymond B. Iglay

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Small unmanned aircraft systems (sUAS) are replacing or supplementing manned aircraft and groundbased surveys in many animal monitoring situations due to better coverage at finer spatial and temporal resolutions, access, cost, bias, impacts, safety, efficiency, and logistical benefits. Various sUAS models and sensors are available with varying features and usefulness depending on survey goals. However, justification for selection of sUAS and sensors are not typically offered in published literature and existing reviews do not adequately cover past and current sUAS applications for animal monitoring nor their associated sUAS model and sensor technologies, taxonomic and geographic scope, flight conditions and …

Recolonizing Carnivores: Is Cougar Predation Behaviorally Mediated By Bears?, Kristin N. Engebretsen, Jon P. Beckmann, Carl W. Lackey, Alyson M. Andreasen, Cody Schroeder, Pat Jackson, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Conservation and management efforts have resulted in population increases and range expansions for some apex predators, potentially changing trophic cascades and foraging behavior. Changes in sympatric carnivore and dominant scavenger populations provide opportunities to assess how carnivores affect one another. Cougars (Puma concolor) were the apex predator in the Great Basin of Nevada, USA, for over 80 years. Black bears (Ursus americanus) have recently recolonized the area and are known to heavily scavenge on cougar kills. To evaluate the impacts of sympatric, recolonizing bears on cougar foraging behavior in the Great Basin, we investigated kill sites of 31 cougars between …