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Utility Of Livestock-Protection Dogs For Deterring Wildlife From Cattle Farms, Thomas M. Gehring, Kurt C. Vercauteren, Megan L. Provost, Anna C. Cellar

USDA Wildlife Services: Staff Publications

Context. Livestock producers worldwide are negatively affected by livestock losses because of predators and wildlife transmitted diseases. In the western Great Lakes Region of the United States, this conflict has increased as grey wolf (Canis lupus) populations have recovered and white-tailed deer (Odocoileus virginianus) have served as a wildlife reservoir for bovine tuberculosis (Myobacterium bovis).

Aims. We conducted field experiments on cattle farms to evaluate the effectiveness of livestock-protection dogs (LPDs) for excluding wolves, coyotes (C. latrans), white-tailed deer and mesopredators from livestock pastures.

Methods. We integrated LPDs on …

Enzymatic Digestion Of Chronic Wasting Disease Prions Bound To Soil, Samuel Saunders, Jason C. Bartz, Kurt C. Vercauteren, Shannon L. Bartelt-Hunt

USDA Wildlife Services: Staff Publications

Chronic wasting disease (CWD) and sheep scrapie can be transmitted via indirect environmental routes, and it is known that soil can serve as a reservoir of prion infectivity. Given the strong interaction between the prion protein (PrP) and soil, we hypothesized that binding to soil enhances prion resistance to enzymatic digestion, thereby facilitating prion longevity in the environment and providing protection from host degradation. We characterized the performance of a commercially available subtilisin enzyme, Prionzyme, to degrade soil-bound and unbound CWD and HY TME PrP as a function of pH, temperature, and treatment time. The subtilisin enzyme effectively degraded PrP …

Identifying Effective Attractants And Rodenticide Baits For Gambian Giant Pouched Rats, Gary W. Witmer, Nathan P. Snow, Rachael Piergross

USDA Wildlife Services: Staff Publications

Following the escape of 8 Gambian giant pouched rats (Gambian rats) from an exotic pet breeder in 1999, Gambian rats became an established invasive species that persists in the wild on Grassy Key, Florida. Because of their large body size, the free-ranging Gambian rats pose a serious threat to native species and agricultural crops, especially if they find their way into mainland Florida. Initiated in 2005, the USDA Wildlife Services has been conducting an eradication and detection program in the Florida Keys. Today however, detecting, baiting, trapping, and removing the now sparse population of Gambian rats are proving difficult. Therefore, …

Sustained Agricitlture: The Need To Manage Rodent Damage, Gary W. Witmer, Grant R. Singleton

USDA Wildlife Services: Staff Publications

The need for sustained agricultural production increases as the world's human population increases, many natural resources grow scarce, and the amount of land devoted to agriculture declines. For example, Vietnam loses 30,000 ha annually of prime lice land to urban development, yet it is the second highest exporter of rice in a world market that reached crisis levels during 2008 (Meerburg et al, 2009b), Between 1960 and 2000, the world's population doubled; in Asia alone the annual population growth until 2020 is estimated at 75 million, which is a lot of new mouths to feed (FAO, 2008). Hence, feeding …

Feral Swine Behavior Relative To Aerial Gunning In Southern Texas, Tyler A. Campbell, David Long, Bruce Leland

USDA Wildlife Services: Staff Publications

Feral swine (Sus scrofa) impact resources through their destructive feeding behavior, competition with native wildlife, and impacts to domestic animal agriculture. We studied aerial gunning on feral swine to determine if aerial gunning altered home range and core area sizes, distances between home range centroids, and distances moved by surviving individuals. We collected data before, during, and after aerial gunning in southern Texas. Using Global Positioning System collars deployed on 25 adult feral swine at 2 study sites, we found home range and core area sizes did not differ before and after aerial gunning. However, feral swine moved …

Contraceptive Efficacy Of A Novel Intrauterine Device (Iud) In White-Tailed Deer, Karl D. Malcolm, Timothy R. Van Deelen, David Drake, Darrel J. Kesler, Kurt C. Vercauteren

USDA Wildlife Services: Staff Publications

Overabundant white-tailed deer (Odocoileus virginianus) pose risks to property, health, and safety of human beings. Public concerns about lethal management can impair efforts to address these issues, particularly in urban settings. Several techniques developed for reducing reproductive output of deer have limited utility because they require repeated dosing to achieve permanent effect and face uncertain regulatory approval for use beyond experimentation. From 10 August 2006 through 30 December 2007, we evaluated the contraceptive efficacy of copper-containing intrauterine devices (IUDs) implanted trans-cervically in white-tailed deer at the E.S. George Reserve in Pinckney, Michigan. Intrauterine devices were implanted before (n …

Seeking A Second Opinion: Uncertainty In Disease Ecology, Brett T. Mcclintock, James D. Nichols, Larissa L. Bailey, Darryl I. Mackenzie, William. L. Kendall, Alan B. Franklin

USDA Wildlife Services: Staff Publications

Analytical methods accounting for imperfect detection are often used to facilitate reliable inference in population and community ecology. We contend that similar approaches are needed in disease ecology because these complicated systems are inherently difficult to observe without error. For example, wildlife disease studies often designate individuals, populations, or spatial units to states (e.g., susceptible, infected, post-infected), but the uncertainty associated with these state assignments remains largely ignored or unaccounted for. We demonstrate how recent developments incorporating observation error through repeated sampling extend quite naturally to hierarchical spatial models of disease effects, prevalence, and dynamics in natural systems. A highly …

A Silent Enzootic Of An Orthopoxvirus In Ghana, West Africa: Evidence For Multi-Species Involvement In The Absence Of Widespread Human Disease, Mary G. Reynolds, Darin S. Carroll, Victoria A. Olson, Christine Hughes, Jack Galley, Anna Likos, Joel M. Montgomery, Richard Suu-Ire, Mubarak O. Kwasi, J. Jeffrey Root, Zach Braden, Jason Abel, Cody Clemmons, Russell Regnery, Kevin Karem, Inger K. Damon

USDA Wildlife Services: Staff Publications

Human monkeypox has never been reported in Ghana, but rodents captured in forested areas of southern Ghana were the source of the monkeypox virus introduced into the United States in 2003. Subsequent to the outbreak in the United States, 204 animals were collected from two commercial trapping sites in Ghana. Animal tissues were examined for the presence of orthopoxvirus (OPXV) DNA using a real-time polymerase chain reaction, and sera were assayed for antibodies against OPXV. Animals from five genera (Cricetomys , Graphiurus , Funiscirus, and Heliosciurus ) had antibodies against OPXV, and three genera (Cricetomys , Graphiurus …

Review Of Issues Concerning The Use Of Reproductive Inhibitors, With Particular Emphasis On Resolving Human-Wildlife Conflicts In North America, Kathleen A. Fagerstone, Lowell A. Miller, Gary Killian, Christi A. Yoder

USDA Wildlife Services: Staff Publications

This manuscript provides an overview of past wildlife contraception efforts and discusses the current state of research. Two fertility control agents, an avian reproductive inhibitor containing the active ingredient nicarbazin and an immunocontraceptive vaccine, have received regulatory approval with the Environmental Protection Agency and are commercially available in the USA. OvoControl G Contraceptive Bait for Canada Geese and Ovo Control for pigeons are delivered as oral baits. An injectable immunocontraceptive vaccine (GonaCon Immunocontraceptive Vaccine) was registered with the Environmental Protection Agency for use in female white-tailed deer in September 2009. An injectable product (GonaCon Immunocontraceptive Vaccine) is registered for use …

Synchronous Monitoring Of Vulture Movements With Satellite Telemetry And Avian Radar, Robert C. Beason, J. S. Humphrey, N. E. Myers, Michael L. Avery

USDA Wildlife Services: Staff Publications

Radar and satellite global positioning system-platform transmitter terminal (GPSPTT) transmitters provide complementary information on the movements and behaviors of individual birds. The GPS-PTT tag provides a snapshot of altitude and location of a specific individual of an identified species at predefined intervals. The history of the individual is known because each transmitter has a unique identification code. The radar cannot identify individuals or even species but it provides continuous position reports (altitude and location) of birds within its detection range. By integrating data from the two sources, the behavior and movements of identified individuals (not possible with radar) can be …

Capture Of Ungulates In Central Asia Using Drive Nets: Advantages And Pitfalls Illustrated By The Endangered Mongolian Saiga Saiga Tatarica Mongolica, Joel Berger, Kim M. Murray, Bayarbaatar Buuveibaatar, Mike R. Dunbar, Badamjav Lkhagvasuren

USDA Wildlife Services: Staff Publications

The study of mammals suffering intense poaching in remote areas poses an increasingly difficult conservation challenge, in part because the extreme flightiness of such species complicates safe capture. The benefits of handling (an opportunity to obtain biological information and attach radio collars) must be weighed against stress to the animals and potential capture-related mortality. In parts of Central Asia this problem is not trivial, as populations have been heavily harvested and opportunities for restraint are often limited. Mongolian saiga Saiga tatarica mongolica, being both Endangered and poached, typifies these issues. Here we describe capture protocols for adult females handled …

Acute Toxicity Of Diphacinone In Northern Bobwhite: Effects On Survival And Blood Clotting, Barnett A. Rattner, Katherine E. Horak, Sarah E. Warner, John J. Johnston

USDA Wildlife Services: Staff Publications

The anticoagulant rodenticide diphacinone was slightly toxic (acuteoralLD₅₀ 2014 mg/kg) to Northern bobwhite (Colinus virginianus) in a 14-day acute toxicity trial. Precise and sensitive assays of blood clotting (prothrombin time, Russell’s Viper venom time, and thrombin clotting time) were adapted for use in quail, and this combination of assays is recommended to measure the effects of anticoagulant rodenticides. A single oral sub lethal dose of diphacinone (434mg/kg body weight) prolonged clotting time at 48 h post-dose compared to controls. At 783 mg/kg (approximate LD₀₂), clotting time was prolonged at both 24 and 48 h post-dose. …

Habitat Succession, Hardwood Encroachment And Raccoons As Limiting Factors For Lower Keys Marsh Rabbits, Paige M. Schmidt, Robert A. Mccleery, Roel R. Lopez, Nova J. Silvy, Jason A. Schmidt

USDA Wildlife Services: Staff Publications

The Lower Keys marsh rabbit (LKMR, Sylvilagus palustris hefneri), a marsh rabbit subspecies endemic to the Lower Keys, Florida was protected in 1990, however, populations continue to decline despite recovery efforts. We hypothesized on-going habitat loss and fragmentation due to succession and hardwood encroachment has led to increased edge, reduced habitat quality, and increased activity by native raccoons (Procyon lotor). These factors reduce the suitability of patches in a later successional state, thus threatening LKMR recovery and metapopulation persistence. We surveyed 150 LKMR patches in 2008, tallying adult and juvenile rabbit pellets, estimating measures of habitat succession …

Evolving Analyses Of The Shoshone River Skunk Rabies Epizootic In Wyoming, Craig A. Ramey, Kenneth H. Mills, Justin W. Fischer

USDA Wildlife Services: Staff Publications

A rabies epizootic occurred in striped skunks from 1988-1993 in a previously rabies-free area of northwestern Wyoming. USDA APHIS Wildlife Services (WS) cooperated with state and local officials by providing a rabies monitoring and depopulation program starting in 1990. Wyoming WS asked for assistance in 1991 from the National Wildlife Research Center (NWRC) to analyze the epizootic’s movements. The goal was to address the public’s concerns about their health and safety and that of their domestic animals and livestock. All rabid skunks were diagnosed by the Wyoming State Veterinary Laboratory (WSVL) using standardized fluorescent antibody testing of brain tissues. The …

Rodent Outbreaks In North America, Gary W. Witmer, Gilbert Proulx

USDA Wildlife Services: Staff Publications

Fluctuations in rodent population densities in North America are a reality. Our understanding of the factors causing such fluctuations is incomplete; therefore, it is important to monitor populations to increase our understanding of natural wildlife communities so as to avoid substantial damage to agriculture, forestry, and urban infrastructures, and to prevent rodent-borne disease transmission to humans. There is a need to establish integrated pest management programs in which monitoring, preventive cultural practices, and various control methods (mechanical, physical, biological, and chemical) are strategically coordinated to maintain rodent population densities at acceptable pest levels.