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Assessment Of Zinc Phosphide Bait Shyness And Tools For Reducing Flavor Aversions, Katherine Horak, N. M. Hofmann, B. A. Kimball

United States Department of Agriculture Wildlife Services: Staff Publications

Prairie voles (Microtus ochrogaster Wagner) cause extensive damage in agricultural, suburban, and urban environments. Control of these animals has historically relied on the use of anticoagulant rodenticides and zinc phosphide. However, shyness to zinc phosphide baits has reduced its efficacy. The aim of this study was to evaluate the factors involved in zinc phosphide bait shyness through preference testing. Baits were made using a rolled oat base and contained various combinations of the components of zinc phosphide baits such as lecithin, magnesium carbonate and known flavor modulators sodium cyclamate and zinc sulfate. Encapsulation of zinc phosphide was also tested …

Efficacy Of Ontario Rabies Vaccine Baits (Onrab) Against Rabies Infection In Raccoons, Amy Gilbert, Shylo Johnson, Nikki Walker, Chad Wickham, Alex Beath, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

In the US, rabies lyssavirus (RABV) only circulates in wildlife species and the most significant reservoir from a public and animal health perspective is the raccoon (Procyon lotor). Management of wildlife rabies relies principally on oral rabies vaccination (ORV) strategies using vaccine-laden bait delivery to freeranging target hosts, in order to reduce the susceptible population to prevent the spread of and eliminate RABV circulation. Our objective was to evaluate efficacy of the Ontario Rabies Vaccine Bait (ONRAB) against a lethal RABV challenge in captive raccoons. Sham or live vaccine baits were offered to 50 raccoons and efficacy was …

Prevalence And Amount Of Feral Swine Damage To Three Row Crops At Planting, Richard M. Engeman, Jason Terry, Leif R. Stephens, Kenneth S. Gruver

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine damage to corn, cotton and peanut crops at planting was assessed for 46 fields in Alabama. Damage was assessed on the basis of prevalence among fields and the quantity lost within each damaged field. Feral swine control by professionals dedicated to that task appeared to greatly reduce the prevalence of damage among fields, as the 14 fields which were within the areas where professional swine control operations took place were not damaged. For the 32 fields not receiving such protection, seven (21.9%) received some level of damage. Of those, 40% (four of 10) peanut fields, 15.4% (two of …

Bad Dog: Feral And Free-Roaming Dogs As Agents Of Conflict, Julie K. Young, D. L. Bergman, M. Ono

United States Department of Agriculture Wildlife Services: Staff Publications

Domestic dogs are ubiquitous where humans reside. While typically considered a companion animal, their ability to thrive as feral and free-roaming animals often results in conflict with wildlife and is an impediment to conservation goals (Gompper, 2013). Home, Bhatnagar & Vanak (2018) provides evidence for this in India, illustrating the role of feral and free-roaming dogs as an invasive species with negative impacts on endemic wildlife, including threatened and endangered species. The authors found that the majority of wildlife attacks by dogs happen when dogs are not with people. It seems that this is the true canine conundrum: humans value …

An Assessment Of The Us Endangered Species Act Recovery Plans: Using Physiology To Support Conservation, Jessica L. Mahoney, Page E. Klug, Wendy L. Reed

United States Department of Agriculture Wildlife Services: Staff Publications

Applying physiology to help solve conservation problems has become increasingly prominent. It is unclear, however, if the increased integration into the scientific community has translated into the application of physiological tools in conservation planning. We completed a review of the use of animal physiology in the US Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) Endangered Species Act (ESA) recovery plans released between 2005 and 2016. Over those 11 years, 135 of the 146 recovery plans mentioned physiology, with 56% including it as background information on the natural history of the species and not as part of …

Modeling The Distributions Of Tegu Lizards In Native And Potential Invasive Ranges, Catherine S. Jarnevich, Mark A. Hayes, Lee A. Fitzgerald, Amy A. Yackel Adams, Bryan G. Falk, Michelle A. M. Collier, Lea R. Bonewell, Page E. Klug, Sergio Naretto, Robert N. Reed

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive reptilian predators can have substantial impacts on native species and ecosystems. Tegu lizards are widely distributed in South America east of the Andes, and are popular in the international live animal trade. Two species are established in Florida (U.S.A.) - Salvator merianae (Argentine black and white tegu) and Tupinambis teguixin sensu lato (gold tegu) – and a third has been recorded there—S. rufescens (red tegu). We built species distribution models (SDMs) using 5 approaches (logistic regression, multivariate adaptive regression splines, boosted regression trees, random forest, and maximum entropy) based on data from the native ranges. We then projected …

Accounting For Location Uncertainty In Azimuthal Telemetry Data Improves Ecological Inference, Brian D. Gerber, Mevin B. Hooten, Christopher P. Peck, Mindy B. Rice, James H. Gammonley, Anthony D. Apa, Amy J. Davis

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Characterizing animal space use is critical for understanding ecological relationships. Animal telemetry technology has revolutionized the fields of ecology and conservation biology by providing high quality spatial data on animal movement. Radio-telemetry with very high frequency (VHF) radio signals continues to be a useful technology because of its low cost, miniaturization, and low battery requirements. Despite a number of statistical developments synthetically integrating animal location estimation and uncertainty with spatial process models using satellite telemetry data, we are unaware of similar developments for azimuthal telemetry data. As such, there are few statistical options to handle these unique data and …

Reimmunization Increases Contraceptive Effectiveness Of Gonadotropin-Releasing Hormone Vaccine (Gonacon-Equine) In Freeranging Horses (Equus Caballus): Limitations And Side Effects, Dan L. Baker, Jenny G. Powers, Jason I. Ransom, Blake E. Mccann, Michael W. Oehler, Jason E. Bruemmer, Nathan L. Galloway, Douglas C. Eckery, Terry M. Nett

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife and humans are increasingly competing for resources worldwide, and a diverse, innovative, and effective set of management tools is needed. Controlling abundance of wildlife species that are simultaneously protected, abundant, competitive for resources, and in conflict with some stakeholders but beloved by others, is a daunting challenge. Free-ranging horses (Equus caballus) present such a conundrum and managers struggle for effective tools for regulating their abundance. Controlling reproduction of female horses presents a potential alternative. During 2009±2017, we determined the long-term effectiveness of GnRH vaccine (GonaCon-Equine) both as a single immunization and subsequent reimmunization on reproduction and side …

Evolutionary Pathway For The 2017 Emergence Of A Novel Highly Pathogenic Avian Influenza A(H7n9) Virus Among Domestic Poultry In Tennessee, United States, Lei Li, Thomas J. Deliberto, Mary L. Killian, Mia K. Torchetti, Xiu-Feng Wan

United States Department of Agriculture Wildlife Services: Staff Publications

In March 2017, a novel highly pathogenic avian influenza A(H7N9) virus was detected at two commercial broiler breeder facilities in Tennessee, United States. In this study, a wild bird low pathogenic avian influenza A virus, A/blue-winged teal/Wyoming/AH0099021/2016(H7N9), was shown to be the probable precursor of the novel H7N9 virus; this low pathogenic virus has eight possible progenitor genes sharing> 99% sequence identity with the novel H7N9 virus. Phylogeographic analyses showed that viral gene constellations that formed and circulated among dabbling ducks contributed to the emergence of the novel H7N9 virus. This is in contrast to the virus that caused the …

Sharing An Environment With Sick Conspecifics Alters Odors Of Healthy Animals, Stephanie S. Gervasi, Maryanne Opiekun, Talia Martin, Gary K. Beauchamp, Bruce A. Kimball

United States Department of Agriculture Wildlife Services: Staff Publications

Body odors change with health status and the odors of sick animals can induce avoidance behaviors in healthy conspecifics. Exposure to sickness odors might also alter the physiology of healthy conspecifics and modify the odors they produce. We hypothesized that exposure to odors of sick (but non-infectious) animals would alter the odors of healthy cagemates. To induce sickness, we injected mice with a bacterial endotoxin, lipopolysaccharide. We used behavioral odor discrimination assays and analytical chemistry techniques followed by predictive classification modeling to ask about differences in volatile odorants produced by two types of healthy mice: those cohoused with healthy conspecifics …

Nutritional Depletion Of Total Mixed Rations By Red-Winged Blackbirds And Projected Impacts On Dairy Cow Performance, James C. Carlson, Randal S. Stahl, John J. Wagner, Terry E. Engle, Shelagh T. Deliberto, Dustin A. Reid, Scott J. Werner

United States Department of Agriculture Wildlife Services: Staff Publications

This Research Communication describes an investigation of the nutritional depletion of total mixed rations (TMR) by pest birds. We hypothesized that species-specific bird depredation of TMR can alter the nutritional composition of the ration and that these changes can negatively impact the performance of dairy cows. Blackbirds selected the high energy fraction of the TMR (i.e., flaked corn) and reduced starch, crude fat and total digestible nutrients during controlled feeding experiments. For Holsteins producing 37·1 kg of milk/d, dairy production modeling illustrated that total required net energy intake (NEI) was 35·8 Mcal/d. For the reference TMR unexposed to blackbirds and …

Falcons Using Orchard Nest Boxes Reduce Fruit-Eating Bird Abundances And Provide Economic Benefits For A Fruit-Growing Region, Megan E. Shave, Stephanie A. Shwiff, Julie L. Elser, Catherine A. Lindell

United States Department of Agriculture Wildlife Services: Staff Publications

1. Suppression of pest species via a native predator is a regulating ecosystem service that has the potential to limit crop damage and produce economic benefits. American kestrels Falco sparverius are widespread, highly mobile, generalist predators that hunt in human-dominated habitats and have the potential to provide previously undocumented ecosystem services in agricultural landscapes.

2. We hypothesized that kestrel activity associated with nest boxes and artificial perches acts to increase perceived predation risk that, in combination with direct predation, can reduce fruit-eating bird abundances in orchards. We used counts and observations of fruit-eating birds from fixed-width transect surveys to investigate …

Detection Of Viruses From Bioaerosols Using Anion Exchange Resin, Joshua W. Schaeffer, Jeffrey C. Chandler, Margaret Davidson, Sheryl L. Magzamen, Alma Perez-Mendez, Stephen J. Reynolds, Lawrence D. Goodridge, John Volckens, Alan B. Franklin, Susan A. Shriner, Bledar Bisha

United States Department of Agriculture Wildlife Services: Staff Publications

This protocol demonstrates a customized bioaerosol sampling method for viruses. In this system, anion exchange resin is coupled with liquid impingement-based air sampling devices for efficacious concentration of negatively-charged viruses from bioaerosols. Thus, the resin serves as an additional concentration step in the bioaerosol sampling workflow. Nucleic acid extraction of the viral particles is then performed directly from the anion exchange resin, with the resulting sample suitable for molecular analyses. Further, this protocol describes a custom-built bioaerosol chamber capable of generating virus-laden bioaerosols under a variety of environmental conditions and allowing for continuous monitoring of environmental variables such as temperature, …

Raccoon (Procyon Lotor) Biomarker And Rabies Antibody Response To Varying Oral Rabies Vaccine Bait Densities In Northwestern Pennsylvania, Kerri Pedersen, Brandon S. Schmit, Thomas J. Deliberto, Jason R. Suckow, Amy J. Davis, Dennis Slate, Richard B. Chipman, Robert L. Hale, Amy T. Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

Distribution of oral rabies vaccine baits has been used as a strategy for managing rabies in the United States since the 1990s. Since that time, efforts have been made to improve baiting strategies with a focus on bait density to maximize both efficiency and cost effectiveness. An optimal rabies management strategy includes a vaccine bait preferred by the target species that is distributed at the minimal density needed to achieve population immunity to prevent rabies spread. The purpose of our pilot study was to examine the effect of 75, 150, and 300 baits/km2 vaccine bait densities on rabies virus neutralizing …

Evaluation Of Movement Behaviors To Inform Toxic Baiting Strategies For Invasive Wild Pigs (Sus Scrofa), Michael Lavelle, Nathan P. Snow, Joseph M. Halseth, Eric H. Vannatta, Heather N. Sanders, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

BACKGROUND: Invasive wild pigs damage agriculture, property, and natural ecosystems. To curtail damage, an effective and humane toxic bait containing microencapsulated sodium nitrite is under development. Strategies for delivering the toxic bait are needed to establish adequate spacing of bait sites, and for simultaneously accustoming wild pigs to the novel bait and wild pig-specific bait stations designed to exclude non-target species.

RESULTS: We monitored movements of 32 Global Positioning System (GPS)-collared wild pigs relative to 41 bait sites containing placebo bait. Among the bait sites,we compared three experimental baiting strategies (and a control) to evaluate which strategy led to the …

Feral Swine Sus Scrofa: A New Threat To The Remaining Breeding Wetlands Of The Vulnerable Reticulated Flatwoods Salamander Ambystoma Bishopi, Kelly C. Jones, Thomas A. Gorman, Brandon K. Rincon, John Allen, Carola A. Haas, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine Sus scrofa have been implicated as a major threat to sensitive habitats and ecosystems as well as threatened wildlife. Nevertheless, direct and indirect impacts on threatened species (especially small, fossorial species) are not well documented. The decline of the U.S. federally endangered reticulated flatwoods salamander Ambystoma bishopi, categorized as Vulnerable on the IUCN Red List, has been rapid and there are few remaining breeding locations for this species. The flatwoods salamander depends on complex herbaceous vegetation in all life stages, including eggs, larvae and adults. Historically sets of hog tracks have been observed only occasionally in the …

Assessing Bird Avoidance Of High-Contrast Lights Using A Choice Test Approach: Implications For Reducing Human-Induced Avian Mortality, Benjamin Goller, Bradley F. Blackwell, Travis L. Devault, Patrice E. Baumhardt, Esteban Fernandez-Juricic

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Avian collisions with man-made objects and vehicles (e.g., buildings, cars, airplanes, power lines) have increased recently. Lights have been proposed to alert birds and minimize the chances of collisions, but it is challenging to choose lights that are tuned to the avian eye and can also lead to avoidance given the differences between human and avian vision. We propose a choice test to address this problem by first identifying wavelengths of light that would over-stimulate the retina using species-specific perceptual models and by then assessing the avoidance/attraction responses of brown-headed cowbirds to these lights during daytime using a behavioral …

Field Trials Of Ontario Rabies Vaccine Bait In The Northeastern Usa, 2012–14, Amy Gilbert, Shylo R. Johnson, Kathleen M. Nelson, Richard B. Chipman, Kurt C. Vercauteren, Timothy P. Algeo, Charles E. Rupprecht, Dennis Slate

United States Department of Agriculture Wildlife Services: Staff Publications

In the US, rabies virus (RV) has been enzootic in raccoons (Procyon lotor) since the late 1940s. Oral rabies vaccination (ORV) was implemented in the 1990s to halt the spread of raccoon RV and continues to be used as a wildlife management tool. Our objective was to evaluate a recombinant human adenovirus–rabies virus glycoprotein vaccine in northern New York, Vermont, and New Hampshire over a 3-yr period, using changes in RV neutralizing antibody (RVNA) seroprevalence in raccoon populations as an immunologic index of ORV impact. Vaccine baits were distributed at 75 baits/km² and 750-m flight-line spacing in …

Diverse Examples From Managing Invasive Vertebrate Species On Inhabited Islands Of The United States, Richard M. Engeman, Michael L. Avery, Aaron B. Shiels, Are R. Berentsen, Kurt C. Vercauteren, Robert T. Sugihara, Anthony G. Duffiney, Craig S. Clark, John D. Eisemann

United States Department of Agriculture Wildlife Services: Staff Publications

A wide array of sizes, ecosystems, cultures, and invasive wildlife are represented among inhabited islands. Here, six cases from the United States of America (US) are selected to illustrate the high diversity of invasive animal management issues and objectives. We outline the background, define the problems and management objectives. We identify the management approaches and discuss the results and influences as they specifically relate to inhabited islands. The examples are: (1) Gambian giant pouched rats on Grassy Key, Florida; (2) coqui frogs on Kaua’i, Hawai’i; (3) feral swine on Cayo Costa Island, Florida; (4) rodents and monitor lizards on Cocos …

How Behavior Of Nontarget Species Affects Perceived Accuracy Of Scat Detection Dog Surveys, Karen E. Dematteo, Linsey W. Blake, Julie K. Young, Barbara Davenport

United States Department of Agriculture Wildlife Services: Staff Publications

Detection dogs, specially trained domestic dogs (Canis familiaris), have become a valuable, noninvasive, conservation tool because they remove the dependence of attracting species to a particular location. Further, detection dogs locate samples independent of appearance, composition, or visibility allowing researchers to collect large sets of unbiased samples that can be used in complex ecological queries. One question not fully addressed is why samples from nontarget species are inadvertently collected during detection dog surveys. While a common explanation has been incomplete handler or dog training, our study aimed to explore alternative explanations. Our trials demonstrate that a scat’s genetic …

Plumage Changes In Double-Crested Cormorants (Phalacrocorax Auritus) Within The Breeding Season: The Risks Of Aging By Plumage, Jennifer E. Chastant, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

Scant attention has been given to the molting patterns of known-age Double-crested Cormorants (Phalacrocorax auritus). In general, subadult individuals are identified with a tan, buffy or mottled chest, and adults are identified with a black chest. While studying Double-crested Cormorant population dynamics in Ontario, Canada, with known-age birds, it was noted that the plumage of many (> 75%) breeding adults changed from black to heavily mottled during the course of the breeding season. No pattern with age was observed; plumage changed in equal proportions for all ages from 2-year-olds to 7-year-olds. A similar but reverse pattern has been …

State Management Of Human– Wildlife Conflicts, Kurt C. Vercauteren, Daniel Hirchert, Scott Hygnstrom

United States Department of Agriculture Wildlife Services: Staff Publications

Many positive experiences are associated with wildlife, from passively watching animals in our backyards to actively hunting in publicly owned forests. Unfortunately, wildlife can be a double- edged sword. Human– wildlife conflicts are pervasive in society, and nearly all segments—wealthy and in need, urban and rural, east and west—can experience problems with wildlife. Agricultural producers lose an estimated $45 billion each year as a result of crop and livestock damage caused by big game, predators, waterfowl, and other wildlife species (Conover 2002). Row crops, forages, rangeland, fruits, vegetables, ornamentals, turf, and livestock are susceptible to damage by wildlife at various …

Behavioral Differences Following Ingestion Of Large Meals And Consequences For Management Of A Harmful Invasive Snake: A Field Experiment, Shane R. Siers, Amy A. Yackel Adams, Robert N. Reed

United States Department of Agriculture Wildlife Services: Staff Publications

Many snakes are uniquely adapted to ingest large prey at infrequent intervals. Digestion of large prey is metabolically and aerobically costly, and large prey boluses can impair snake locomotion, increasing vulnerability to predation. Cessation of foraging and use of refugia with microclimates facilitating digestion are expected to be strategies employed by free-ranging snakes to cope with the demands of digestion while minimizing risk of predation. However, empirical observations of such submergent behavior from field experiments are limited. The brown treesnake (Serpentes: Colubridae: Boiga irregularis) is a nocturnal, arboreal, colubrid snake that was accidentally introduced to the island of Guam, …

Estimating The Economic Impact Of Canine Rabies To Viet Nam 2005–2014, Stephanie A. Shwiff, Vienna R. Brown, Thu Trang Dao, Julie Elser, Hoang Xuan Trung, Nguyen Ngoc Tien, Nguyen Thi Huong, Nguyen Thi Thanh Huong, Arthorn Riewpaiboon, Karina Ernst, Steven Shwiff, David Payne

United States Department of Agriculture Wildlife Services: Staff Publications

The global economic impact of canine rabies has been estimated by several studies. Asia bears a disproportionate burden of this zoonosis due to high levels of human deaths and rates of post-exposure prophylaxis (PEP), but low investment in preventative dog vaccination. The same factors that cause rabies to burden much of Asia are also present in Viet Nam. This study estimated the economic burden of canine rabies in a societal perspective including direct and indirect cost of rabies in dogs, livestock, and humans. Using data collected from personal interviews, published literature, published and supplementary reports, and primary data collection, we …

Quantification Of Avian Hazards To Military Aircraft And Implications For Wildlife Management, Morgan Pfeiffer, Bradley F. Blackwell, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Collisions between birds and military aircraft are common and can have catastrophic effects. Knowledge of relative wildlife hazards to aircraft (the likelihood of aircraft damage when a species is struck) is needed before estimating wildlife strike risk (combined frequency and severity component) at military airfields. Despite annual reviews of wildlife strike trends with civil aviation since the 1990s, little is known about wildlife strike trends for military aircraft. We hypothesized that species relative hazard scores would correlate positively with aircraft type and avian body mass. Only strike records identified to species that occurred within the U.S. (n = 36,979) …

Fertility Control For Managing Free-Roaming Feral Cattle In Hong Kong, Giovanna Massei, Ka-Kei Koon, Siu-Iun Law, Matt Gomm, Darcy S. O. Mora, Rebecca Callaby, Kate Palphramand, Douglas C. Eckery

United States Department of Agriculture Wildlife Services: Staff Publications

Human-wildlife conflicts are increasing worldwide. For instance, growing numbers of free-roaming feral cattle in Hong Kong are causing traffic accidents and damaging crops. Public antipathy towards lethal methods to manage wildlife has promoted research into alternative options, such as fertility control. The aims of this study were to assess the potential side effects and effectiveness of the injectable immunocontraceptive vaccine GonaCon on free-roaming feral cattle in Hong Kong. Sixty female cattle were captured and randomly assigned to treatment or control groups. Treatment animals were administered one dose of GonaCon, followed by a booster dose 3–6 months later. Control animals were …

Roads Do Not Increase Carrion Use By A Vertebrate Scavenging Community, Jacob E. Hill, Travis L. Devault, James C. Beasley, Olin E. Rhodes Jr., Jerrold L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife-vehicle collisions introduce a considerable amount of carrion into the environment, but scavenger use of this resource has not been extensively investigated. Scavengers may use roads for reliable foraging opportunities, but might also use roads for other purposes and encounter carrion opportunistically. We examined scavenging of carrion along linear features by placing 52 rabbit carcasses in each of three treatments in forested habitat during winter (Dec 2016-Mar 2017) in South Carolina, USA: roads, power line clearings (linear feature with fewer carcasses than roads due to lack of road kill), and forest interior. We used motion-activated cameras to compare arrival times …

Evaluating An Alleged Mimic Of The Monarch Butterfly: Neophasia (Lepidoptera: Pieridae) Butterflies Are Palatable To Avian Predators, Dale A. Halbritter, Johnalyn M. Gordon, Kandy L. Keacher, Michael L. Avery, Jaret C. Daniels

United States Department of Agriculture Wildlife Services: Staff Publications

Some taxa have adopted the strategy of mimicry to protect themselves from predation. Butterflies are some of the best representatives used to study mimicry, with the monarch butterfly, Danaus plexippus (Lepidoptera: Nymphalidae) a well-known model. We are the first to empirically investigate a proposed mimic of the monarch butterfly: Neophasia terlooii, the Mexican pine white butterfly (Lepidoptera: Pieridae). We used captive birds to assess the palatability of N. terlooii and its sister species, N. menapia, to determine the mimicry category that would best fit this system. The birds readily consumed both species of Neophasia and a palatable control species but …

Cross-Fostering As A Conservation Tool To Augment Endangered Carnivore Populations, Eric M. Gese, William T. Waddell, Patricia A. Terletzky, Chris F. Lucash, Scott R. Mclellan, Susan K. Behrns

United States Department of Agriculture Wildlife Services: Staff Publications

Cross-fostering offspring with nonbiological parents could prove useful to augment populations of endangered carnivores. We used cross-fostering to augment captive-born and wild-born litters for the endangered red wolf (Canis rufus). Between 1987 and 2016, 23 cross-fostering events occurred involving captive-born pups fostered into captive litters (n = 8 events) and captive-born pups fostered into wild recipient litters (n = 15 events). Percentage of pups surviving 3 and 12 months was 91.7% for captive-born pups fostered into captive recipient litters. For pups fostered into wild litters, percentage of pups surviving 5 months was > 94% among fostered pups …

Persistence Of Maternal Antibodies To Influenza A Virus Among Captive Mallards (Anas Platyrhynchos), Katherine L. Dirsmith, J. Jeffrey Root, Kevin T. Bentler, Heather J. Sullivan, Andrea B. Liebowitz, Lauren H. Petersen, Hailey E. Mclean, Susan A. Shriner

United States Department of Agriculture Wildlife Services: Staff Publications

Wild waterfowl are maintenance hosts of most influenza A virus (IAV) subtypes and are often the subjects of IAV surveillance and transmission models. While maternal antibodies have been detected in yolks and in nestlings for a variety of wild bird species and pathogens, the persistence of maternal antibodies to IAVs in mallard ducklings (Anas platyrhynchos) has not been previously investigated. Nonetheless, this information is important for a full understanding of IAV transmission dynamics because ducklings protected by maternal antibodies may not be susceptible to infection. In this study, we examined the transfer of IAV-specific maternal antibodies to ducklings. …