Veterinary Microbiology and Immunobiology Commons^™

Spatially Structured Brown-Headed Cowbird Control Measures And Their Effects On Kirtland’S Warbler Long-Term Population Sustainability, Eric A. Margenau, Nathan W. Cooper, Donald J. Brown, Deahn M. Donner, Peter P. Marra, Pat Ryan

United States Department of Agriculture Wildlife Services: Staff Publications

Context: Brown-headed cowbirds (Molothrus ater), through brood parasitism, can exert extrinsic population growth pressures on North American songbirds. Cowbird removal programs may reduce parasitism rates on host species but can be expensive and difficult to implement throughout a host species’ breeding range.

Aim: We estimated cowbird abundance and nest parasitism rates within Kirtland’s warbler (Setophaga kirtlandii) primary breeding range in Michigan, USA, and determined the maximum sustainable parasitism rate for Kirtland’s warblers under several spatially structured cowbird removal designs.

Methods: We conducted point counts to estimate cowbird abundance and monitored nests to quantify nest parasitism rates …

African Swine Fever, Vienna R. Brown, Julianna B. Lenoch, Courtney F. Bowden

United States Department of Agriculture Wildlife Services: Staff Publications

At the time of writing this chapter, a global pandemic of African swine fever (ASF) is ongoing with the virus having moved from Eastern Europe, Asia, and into the Caribbean—leaving swine production in devastation along the way. Due to the global spread of African swine fever virus (ASFV), the persistence of the virus, and the increasing number of endemic countries, this disease poses an imminent threat of introduction into North America and other countries that are currently ASF free. Throughout the chapter, we reference Eurasian wild boar (Sus scrofa) which are charismatic megafauna that are native to Europe and Asia. …

Factors Affecting The Recovery Of Mexican Wolves In The Southwest United States, Stewart W. Breck, Amy J. Davis, John Oakleaf, David L. Bergman, Jim Devos, J. Paul Greer, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

1. Recovering and maintaining large carnivore populations is a global conservation challenge that requires better knowledge of the factors affecting their populations, particularly in shared landscapes (i.e. non-protected areas where people occupy and or utilize the land).
2. The Mexican wolf (Canis lupus baileyi) is an endangered wolf subspecies being recovered on shared landscapes in the Southwest United States and Mexico. We used data from the U.S. program to model population growth, evaluate the impact of management removal and illegal killing relative to other demographic factors, and test hypotheses about factors influencing rates of management removal and illegal killing.
3. From …

Can Demographic Histories Explain Long-Term Isolation And Recent Pulses Of Asymmetric Gene Flow Between Highly Divergent Grey Fox Lineages?, Sophie Preckler-Quisquater, Elizabeth M. Kierepka, Dawn M. Reding, Antoinette J. Piaggio, Benjamin N. Sacks

United States Department of Agriculture Wildlife Services: Staff Publications

Secondary contact zones between deeply divergent, yet interfertile, lineages provide windows into the speciation process. North American grey foxes (Urocyon cinereoargenteus) are divided into western and eastern lineages that diverged approximately 1 million years ago. These ancient lineages currently hybridize in a relatively narrow zone of contact in the southern Great Plains, a pattern more commonly observed in smaller-bodied taxa, which suggests relatively recent contact after a long period of allopatry. Based on local ancestry inference with whole-genome sequencing (n = 43), we identified two distinct Holocene pulses of admixture. The older pulse (500–3500 YBP) reflected unidirectional …

Role Of Social Structure In Establishment Of An Invasive Large Mammal After Translocation, Lindsay M. Clontz, Anni Yang, Sarah M. Chinn, Kim M. Pepin, Kurt C. Vercauterten, George Wittemyer, Ryan S. Miller, James C. Beasley

United States Department of Agriculture Wildlife Services: Staff Publications

Background

Data on the movement behavior of translocated wild pigs is needed to develop appropriate response strategies for containing and eliminating new source populations following translocation events. We conducted experimental trials to compare the home range establishment and space-use metrics, including the number of days and distance traveled before becoming range residents, for wild pigs translocated with their social group and individually.

Results

We found wild pigs translocated with their social group made less extensive movements away from the release location and established a stable home range ~5 days faster than those translocated individually. We also examined how habitat quality …

Investigation Of Risk Factors For Introduction Of Highly Pathogenic Avian Influenza H5n1 Infection Among Commercial Turkey Operations In The United States, 2022: A Case-Control Study, Kelly A. Patyk, Victoria L. Fields, Andrea L. Beam, Matthew A. Branan, Rachel E. Mcguigan, Alice Green, Mia K. Torchetti, Kristina Lantz, Alexis Freifeld, Katherine Marshall, Amy H. Delgado

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction: The 2022–2023 highly pathogenic avian influenza (HPAI) H5N1 outbreak in the United States (U.S.) is the largest and most costly animal health event in U.S. history. Approximately 70% of commercial farms affected during this outbreak have been turkey farms. Methods: We conducted a case-control study to identify potential risk factors for introduction of HPAI virus onto commercial meat turkey operations. Data were collected from 66 case farms and 59 control farms in 12 states. Univariate and multivariable analyses were conducted to compare management and biosecurity factors on case and control farms. Results: Factors associated with increased risk of infection …

Outbreak Of Epizootic Hemorrhagic Disease In Captive Reindeer (Rangifer Tarandus), Emma H. Torii, Arno Wünschmann, Mia Kim Torchetti, Leo Koster, Albert Van Geelen, Randy Atchison, Anne Rivas

United States Department of Agriculture Wildlife Services: Staff Publications

In September 2020, an outbreak of epizootic hemorrhagic disease occurred in captive reindeer (Rangifer tarandus) and was associated with neurological signs and mortality. Four reindeer died or were euthanized after acute illness over a 12-day period. Affected reindeer displayed abnormal behavior, neurologic signs, lethargy, and/or lameness. The most consistent gross finding was dark red streaks throughout the adrenal gland cortices (4/4). One animal had acute hemorrhage involving the subcutis and skeletal muscles over the ventrolateral body wall and back, and abomasal serosa. Histologically, the most common lesions were adrenal gland cortical hemorrhage (4/4) with necrosis (3/4) and lymphoplasmacytic meningoencephalitis with …

Investigation Of Risk Factors For Introduction Of Highly Pathogenic Avian Influenza H5n1 Virus Onto Table Egg Farms In The United States, 2022: A Case–Control Study, Alice L. Green, Matthew Branan, Victoria L. Fields, Kelly Patyk, Stephanie K. Kolar, Andrea Beam, Katherine Marshall, Rachel Mcguigan, Matthew Vuolo, Alexis Freifeld, Mia Kim Torchetti, Kristina Lantz, Amy H. Delgado

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction: The 2022–2023 highly pathogenic avian influenza (HPAI) H5N1 outbreak in the United States (U.S.) is the most geographically extensive and costly animal health event in U.S. history. In 2022 alone, over 57 million commercial and backyard poultry in 47 U.S. states were affected. Over 75% of affected poultry were part of the commercial table egg production sector. Methods: We conducted a case–control study to identify potential risk factors for introduction of HPAI virus onto commercial table egg operations. Univariate and multivariable analyses were conducted to compare farm characteristics, management, and biosecurity factors on case and control farms. Results: Factors …

Raccoons (Procyon Lotor) Show Higher Trypanosoma Cruzi Detection Rates Than Virginia Opossums (Didelphis Virginiana) In South Carolina, Usa, David A. Bernasconi, Madison L. Miller, Jacob E. Hill, Pooja Gupta, Richard Chipman, Amy Gilbert, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

Chagas disease, a significant public health concern in the Americas, is caused by a protozoan parasite, Trypanosoma cruzi. The life cycle of T. cruzi involves kissing bugs (Triatoma spp.) functioning as vectors and mammalian species serving as hosts. Raccoons (Procyon lotor) and opossums (Didelphis virginiana) have been identified as important reservoir species in the life cycle of T. cruzi, but prevalence in both species in the southeastern United States is currently understudied. We quantified T. cruzi prevalence in these two key reservoir species across our study area in South Carolina, USA, and …

Rabies Virus Serosurvey Of The Small Indian Mongoose (Urva Auropunctata) Across Multiple Habitats In Puerto Rico, 2014–21, Are R. Berentsen, Mel J. Rivera-Rodriguez, Fabiola B. Torres-Toledo, Amy J. Davis, Richard Chipman, Amy Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

The small Indian mongoose (Urva auropuncata) is a rabies reservoir in Puerto Rico and accounts for over 70% of reported animal rabies cases annually. The presence of rabies virus-neutralizing antibodies (RVNA) is often used as a tool to measure exposure to rabies virus in wildlife populations. We conducted a serosurvey of mongooses at 11 sites representing six habitat types across Puerto Rico. We collected a serum sample from 464 individual mongooses during 2014–2021. Overall, 80/464 (17.0%; 95% confidence interval, 14.1–20.9%; 55 male, 23 female, and two sexes not recorded) of individual mongooses sampled across all habitats were RVNA …

Predicting Dispersal And Conflict Risk For Wolf Recolonization In Colorado, Mark A. Ditmer, George Wittemyer, Katherine A. Zeller, Stewart W. Breck, Robert J. Fletcher Jr., Kevin R. Crooks

United States Department of Agriculture Wildlife Services: Staff Publications

1. The colonization of suitable yet unoccupied habitat due to natural dispersal or human introduction can benefit recovery of threatened species. Predicting habitat suitability and conflict potential of colonization areas can facilitate conservation planning.

2. Planning for reintroduction of gray wolves (Canis lupus) to the United States state of Colorado is underway. Assessing which occupancy sites minimize the likelihood of human-wolf conflict during dispersal events and seasonal movements is critical to the success of this initiative.

3. We used a spatial absorbing Markov chain (SAMC) framework, which extends random walk theory and probabilistically accounts for both movement behavior …

Straight From The Coyote’S Mouth: Genetic Identification Of Prey Through Oral Swabs Of Predators, Julie K. Young, Amanda M. Mast, James A. Walton, Torrey Rodgers, Antionette J. Piaggio, Daniel R. Taylor, Karen E. Mock

United States Department of Agriculture Wildlife Services: Staff Publications

Human-carnivore conflicts often involve the depredation of domestic livestock. These depredation events are rarely observed, yet mitigation typically involves identifying the species or individual involved for removal or relocation. We tested a molecular method to identify individuals involved in depredation events using mouth swabs to determine if prey DNA could be detected, and for how long. We fed mule deer Odocoileus hemionus meat to captive coyotes Canis latrans and swabbed their mouths at five predetermined intervals between 2–72 h after consumption of the deer meat. We assessed two different molecular forensic methods to analyze the saliva swabs: qPCR for species …

Development And Evaluation Of Prototype Toxicant-Delivery Bait Stations For The Control Of The Small Indian Mongoose, Carmen C. Antaky, Robert T. Sugihara, Israel L. Leinbach, Shane R. Siers, Emily W. Ruell, Steven C. Hess

United States Department of Agriculture Wildlife Services: Staff Publications

We conducted research to develop a safe and effective toxic bait to control the small Indian mongoose (Urva auropunctata), an invasive vertebrate predator impacting the survival of native species in Hawai‘i (United States) and in other parts of the world. A preserved fish-based bait product was found to be highly palatable to mongooses in cage trials and subsequent formulations with diphacinone (0.005%) showed promise as an efficacious toxic bait for mongooses. This product is intended for future use to control mongooses in conservation and urban areas, and as a biosecurity tool at ports of entry to address accidental …

Environmental Transmission Of Influenza A Virus In Mallards, Kim M. Pepin, Clinton B. Leach, Nicole L. Barrett, Jeremy W. Ellis, Kaci K. Vandalen, Colleen T. Webb, Susan A. Shriner

United States Department of Agriculture Wildlife Services: Staff Publications

Abstract

Influenza A viruses present a major challenge for animal and human health. They circulate widely in wild waterfowl and frequently spillover into poultry, emphasizing the need for risk-based surveillance in wild birds and an understanding of the relative importance of different transmission mechanisms. We addressed this objective with a replicated (N = 6) experimental infection study in which we serially exposed eight cohorts of four naïve contact mallards to an experimentally infected mallard and a shared water pool. Viral concentration in the water was a better predictor of transmission than several direct measures of viral shedding in the …

Genomic Regions Associated With Pseudorabies Virus Infection Status In Naturally Infected Feral Swine (Sus Scrofa), Courtney F. Bowden, Jennifer N. Kiser, Ryan S. Miller, Alexandra C. Buckley, Paola M. Boggiatto, Rachael M. Giglio, Vienna R. Brown, Dorian Garrick, Holly L. Neibergs, Antoinette J. Piaggio, Scott E. Speidel, Timothy J. Smyser

United States Department of Agriculture Wildlife Services: Staff Publications

Pseudorabies virus (PRV)—the causative agent of Aujeszky’s disease—was eliminated from commercial pig production herds in the United States (US) in 2004; however, PRV remains endemic among invasive feral swine (Sus scrofa). The circulation of PRV among abundant, widespread feral swine populations poses a sustained risk for disease spillover to production herds. Risk–based surveillance has been successfully implemented for PRV in feral swine populations in the US. However, understanding the role of host genetics in infection status may offer new insights into the epidemiology and disease dynamics of PRV that can be applied to management strategies. Genetic mechanisms underlying …

Estimating Northern Spotted Owl (Strix Occidentalis Caurina) Pair Detection Probabilities Based On Call-Back Surveys Associated With Long-Term Mark-Recapture Studies, 1993–2018, Katie M. Dugger, Alan B. Franklin, Damon B. Lesmeister, Raymond J. Davis, J. David Wiens, Gary C. White, James D. Nichols, James E. Hines, Charles B. Yackulic, Carl J. Schwarz, Steven A. Ackers, L. Steven Andrews, Larissa L. Bailey, Robin Bown, Jesse Burgher, Kenneth P. Burnham, Peter C. Carlson, Tara Chestnut, Mary M. Conner, Krista E. Dilione, Eric D. Forsman, Scott A. Gremel, Keith A. Hamm, Dale R. Herter, J. Mark Higley, Rob B. Horn, Julianna M. Jenkins, William L. Kendall, David W. Lapmphear, Christopher Mccafferty, Trent L. Mcdonald, Janice A. Reid, Jeremy T. Rockweit, David C. Simon, Stan G. Sovern, James K. Swingle, Heather Wise

United States Department of Agriculture Wildlife Services: Staff Publications

The northern spotted owl (Strix occidentalis caurina; hereinafter NSO) was listed as “threatened” under the Endangered Species Act in 1990 and population declines have continued since that listing. Given the species’ protected status, any proposed activities on Federal lands that might impact NSO require consultation with U.S. Fish and Wildlife Service and part of that consultation often includes surveys to determine presence and occupancy status of the species in the proposed activity area. The objective of this report is to present study-area specific estimates of the probability of detection for NSO pairs from twelve 2-week seasonal survey periods …

Light Wavelength And Pulsing Frequency Affect Avoidance Responses Of Canada Geese, Ryan B. Lunn, Patrice E. Baumhardt, Bradley F. Blackwell, Jean Paul Freyssinier, Esteban Fernández-Juricic

United States Department of Agriculture Wildlife Services: Staff Publications

Collisions between birds and aircraft cause bird mortality, economic damage, and aviation safety hazards. One proposed solution to increasing the distance at which birds detect and move away from an approaching aircraft, ultimately mitigating the probability of collision, is through onboard lighting systems. Lights in vehicles have been shown to lead to earlier reactions in some bird species but they could also generate attraction, potentially increasing the probability of collision. Using information on the visual system of the Canada goose (Branta canadensis), we developed light stimuli of high chromatic contrast to their eyes. We then conducted a controlled …

Assessment Of Spilled Toxic Bait By Wild Pigs And Potential Risk To Non-Target Species, John C. Kinsey, Justin A. Foster, Nathan P. Snow, Jason D. Wishart, Linton D. Staples, Janis K. Bush, Kurt V. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Background

In 2018, a sodium nitrite (SN)-based toxic bait for invasive wild pigs (hereafter wild pigs; Sus scrofa), was evaluated to determine its effectiveness in reducing local wild pig populations in Texas. Localized population reductions of > 70% were achieved, but spillage of bait outside wild pig-specific feeders (bait stations) caused by feeding wild pigs resulted in the deaths of non-target animals. To evaluate risks to non-target animals, we tested whether bait presentation influenced the total amount of bait spilled by wild pigs and estimated the associated risk to non-target species.

Results

We found that bait spilled outside bait stations …

Population Density Of The Small Indian Mongoose (Urva Auropunctata) Across Multiple Habitat Types And Seasons In Puerto Rico, Are R. Berentsen, Caroline C. Sauvé, Mel J. Rivera-Rodriguez, Fabiola B. Torres-Toledo, Richard B. Chipman, Amy T. Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

The small Indian mongoose (Urva auropunctata) is a rabies reservoir on several Caribbean Islands including Puerto Rico. In the continental United States, oral rabies vaccination (ORV) has been used to control and locally eliminate rabies viruses targeting meso-carnivores including raccoons (Procyon lotor), grey foxes (Urocyon cinereoargenteus), and coyotes (Canis latrans), and has more recently been proposed to mitigate and control mongoose rabies in Puerto Rico. A fundamental understanding of the population density of the target species is an important factor in planning bait application rates prior to ORV operations. In Puerto Rico, …

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 …