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Contact Rates With Nesting Birds Before And After Invasive Snake Removal: Estimating The Effects Of Trap-Based Control, Amy A. Yackel Adams, Melia G. Nafus, Page E. Klug, Björn Lardner, M.J. Mazurek, Julie A. Savidge, Robert N. Reed

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive predators are responsible for almost 60% of all vertebrate extinctions worldwide with the most vulnerable faunas occurring on islands. The brown treesnake (Boiga irregularis) is a notorious invasive predator that caused the extirpation or extinction of most native forest birds on Guam. The success of avian reintroduction efforts on Guam will depend on whether snake-control techniques sufficiently reduce contact rates between brown treesnakes and reintroduced birds. Mouse-lure traps can successfully reduce brown treesnake populations at local scales. Over a 22-week period both with and without active snake removal, we evaluated snake-trap contact rates for mouse- and bird-lure traps. Bird-lure …

An Evaluation Of The Registration And Use Prospects For Four Candidate Toxicants For Controlling Invasive Mongooses (Herpestes Javanicus Auropunctatus), Emily W. Ruell, Chris N. Niebuhr, Robert T. Sugihara, Shane R. Siers

United States Department of Agriculture Wildlife Services: Staff Publications

The eradication or control of invasive small Indian mongooses from islands likely requires toxic baiting when removal by trapping proves insufficient. The one toxic bait currently registered for mongooses in the United States has relatively low palatability and efficacy for mongooses. Developing and registering a new pesticide can be very expensive, while funding for developing toxicants for mongooses is limited. Once registered, use of a toxic bait may be hindered by other factors, such as public opposition to an inhumane toxicant, poorer efficacy than expected, or if the toxic bait is difficult for applicators to apply or store. Therefore, we …

Transmission Dynamics Of Toxoplasma Gondii In Arctic Foxes (Vulpes Lagopus): A Long-Term Mark-Recapture Serologic Study At Karrak Lake, Nunavut, Canada, Emilie Bouchard, Stacey A. Elmore, Ray T. Alisauskas, Gustaf Samelius, Alvin A. Gajadhar, Keaton Schmidt, Sasha Ross, Emily J. Jenkins

United States Department of Agriculture Wildlife Services: Staff Publications

Transmission dynamics of Toxoplasma gondii, a parasite of importance for wildlife and human health, are enigmatic in the Arctic tundra, where free-ranging wild and domestic felid definitive hosts are absent and rarely observed, respectively. Through a multiyear mark-recapture study (2011– 17), serosurveillance was conducted to investigate transmission of T. gondii in Arctic foxes (Vulpes lagopus) in the Karrak Lake region, Nunavut, Canada. Sera from adult foxes and fox pups were tested for antibodies to T. gondii by using serologic methods, including the indirect fluorescent antibody test, direct agglutination test, and modified agglutination test. The overall seroprevalence was 39% in adults …

Not All Surveillance Data Are Created Equal—A Multi‐Method Dynamic Occupancy Approach To Determine Rabies Elimination From Wildlife, Amy J. Davis, Jordona D. Kirby, Richard B. Chipman, Kathleen M. Nelson, Tatiana Xifara, Colleen T. Webb, Ryan Wallace, Amy T. Gilbert, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

1. A necessary component of elimination programmes for wildlife disease is effective surveillance. The ability to distinguish between disease freedom and non‐detection can mean the difference between a successful elimination campaign and new epizootics. Understanding the contribution of different surveillance methods helps to optimize and better allocate effort and develop more effective surveillance programmes.

2. We evaluated the probability of rabies virus elimination (disease freedom) in an enzootic area with active management using dynamic occupancy modelling of 10 years of raccoon rabies virus (RABV) surveillance data (2006–2015) collected from three states in the eastern United States. We estimated detection probability …

Survival, Fidelity, And Dispersal Of Double-Crested Cormorants On Two Lake Michigan Islands, Christopher R. Ayers, Katie C. Hanson-Dorr, Ken Stromborg, Todd W. Arnold, Jacob S. Ivan, Brian S. Dorr

United States Department of Agriculture Wildlife Services: Staff Publications

Colony fidelity and dispersal can have important consequences on the population dynamics of colonial-nesting birds. We studied survival and inter-colony movements of Double-crested Cormorants (Phalacrocorax auritus; cormorants) nesting at Spider and Pilot islands, located 9 km apart in western Lake Michigan, during 2008–2014. We used live resighting and dead recovery data from both colonies, plus dead recoveries from throughout North America, in a multistate live and dead encounter model to estimate annual survival, inter-colony movements, plus temporary and permanent emigration to unmonitored sites. Annual survival averaged 0.37 (annual process variation, ˆ = 0.07) for hatch-year, 0.78 (ˆ= 0.08) for secondyear, …

Use Of Unmanned Aircraft Systems (Uas) And Multispectral Imagery For Quantifying Agricultural Areas Damaged By Wild Pigs, Justin W. Fischer, Kelsey Greiner, Mark W. Lutman, Bryson L. Webber, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) cause extensive damage to agricultural crops, resulting in lost production and income. A major challenge associated with assessing damage to crops is locating and quantifying damaged areas within agricultural fields. We evaluated a novel method using multispectral high-resolution aerial imagery, collected from sensors mounted on unmanned aircraft systems (UAS), and feature extraction techniques to detect and map areas of corn fields damaged by wild pigs in southern Missouri, USA. Damaged areas were extracted from orthomosaics using visible and near-infrared band combinations, an object-based classification approach, and hierarchical learning cycles. To validate estimates we also collected ground …

Confronting Models With Data: The Challenges Of Estimating Disease Spillover, Paul C. Cross, Diann J. Prosser, Andrew M. Ramey, Ephraim M. Hanks, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

For pathogens known to transmit across host species, strategic investment in disease control requires knowledge about where and when spillover transmission is likely. One approach to estimating spillover is to directly correlate observed spillover events with covariates. An alternative is to mechanistically combine information on host density, distribution and pathogen prevalence to predict where and when spillover events are expected to occur. We use several case studies at the wildlife–livestock disease interface to highlight the challenges, and potential solutions, to estimating spatiotemporal variation in spillover risk. Datasets on multiple host species often do not align in space, time or resolution, …

Typha (Cattail) Invasion In North American Wetlands: Biology, Regional Problems, Impacts, Ecosystem Services, And Management, Sheel Bansal, Shane C. Lishawa, Sue Newman, Brian A. Tangen, Douglas Wilcox, Dennis Albert, Michael J. Anteau, Michael J. Chimney, Ryann L. Cressey, Edward Dekeyser, Kenneth J. Elgersma, Sarah A. Finkelstein, Joanna Freeland, Richard Grosshans, Page E. Klug, Daniel J. Larkin, Beth A. Lawrence, George Linz, Joy Marburger, Gregory Noe, Clint Otto, Nicholas Reo, Jennifer Richards, Curtis Richardson, Leroy Rodgers, Amy J. Schrank, Dan Svedarsky, Steven Travis, Nancy Tuchman, Lisamarie Windham-Myers

United States Department of Agriculture Wildlife Services: Staff Publications

Typha is an iconic wetland plant found worldwide. Hybridization and anthropogenic disturbances have resulted in large increases in Typha abundance in wetland ecosystems throughout North America at a cost to native floral and faunal biodiversity. As demonstrated by three regional case studies, Typha is capable of rapidly colonizing habitats and forming monodominant vegetation stands due to traits such as robust size, rapid growth rate, and rhizomatic expansion. Increased nutrient inputs into wetlands and altered hydrologic regimes are among the principal anthropogenic drivers of Typha invasion. Typha is associated with a wide range of negative ecological impacts to wetland and agricultural …

Extreme Site Fidelity As An Optimal Strategy In An Unpredictable And Homogeneous Environment, 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

1. Animal site fidelity structures space use, population demography and ultimately gene flow. Understanding the adaptive selection for site fidelity patterns provides a mechanistic understanding to both spatial and population processes. This can be achieved by linking space use with environmental variability (spatial and temporal) and demographic parameters. However, rarely is the environmental context that drives the selection for site fidelity behaviour fully considered.

2. We use ecological theory to understand whether the spatial and temporal variability in breeding site quality can explain the site fidelity behaviour and demographic patterns of Gunnison sage‐grouse (Centrocercus minimus). We examined female site fidelity …

Ecological Interventions To Prevent And Manage Zoonotic Pathogen Spillover, Susanne H. Sokolow, Nicole Nova, Kim M. Pepin, Alison J. Peel, Juliet R.C. Pulliam, Kezia Manlove, Paul C. Cross, Daniel J. Becker, Raina K. Plowright, Hamish Mccallum, Giulio A. De Leo

United States Department of Agriculture Wildlife Services: Staff Publications

Spillover of a pathogen from awildlife reservoir into a human or livestock host requires the pathogen to overcome a hierarchical series of barriers. Interventions aimed at one or more of these barriers may be able to prevent the occurrence of spillover. Here, we demonstrate how interventions that target the ecological context in which spillover occurs (i.e. ecological interventions) can complement conventional approaches like vaccination, treatment, disinfection and chemical control. Accelerating spillover owing to environmental change requires effective, affordable, durable and scalable solutions that fully harness the complex processes involved in cross-species pathogen spillover.

This article is part of the theme …

Scavenging In The Anthropocene: Human Impact Drives Vertebrate Scavenger Species Richness At A Global Scale, Esther Sebastián‐González, Jomar Magalhães Barbosa, Juan M. Pérez‐García, Zebensui Morales‐Reyes, Francisco Botella, Pedro P. Olea, Patricia Mateo‐Tomás, Marcos Moleón, Fernando Hiraldo, Eneko Arrondo, José A. Donázar, Ainara Cortés‐Avizanda, Nuria Selva, Sergio A. Lambertucci, Aishwarya Bhattacharjee, Alexis Brewer, Erin Abernethy, Olin E. Rhodes Jr., Kelsey Turner, James C. Beasley, Travis L. Devault, Andrés Ordiz, Camilla Wikenros, Barbara Zimmermann, Petter Wabakken, Christopher C. Wilmers, Justine A. Smith, Corinne J. Kendall, Darcy Ogada, Evan R. Buechley, Ethan Frehner, Maximilian L. Allen, Heiko U. Wittmer, James R.A. Butler, Johan T. Du Toit, John Read, David Wilson, Klemen Jerina, Miha Krofel, Rich Kostecke, Richard Inger, Arockianathan Samson, Lara Naves‐Alegre, José A. Sánchez‐Zapata

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding the distribution of biodiversity across the Earth is one of the most challenging questions in biology. Much research has been directed at explaining the species latitudinal pattern showing that communities are richer in tropical areas; however, despite decades of research, a general consensus has not yet emerged. In addition, global biodiversity patterns are being rapidly altered by human activities. Here, we aim to describe large‐scale patterns of species richness and diversity in terrestrial vertebrate scavenger (carrion‐consuming) assemblages, which provide key ecosystem functions and services. We used a worldwide dataset comprising 43 sites, where vertebrate scavenger assemblages were identified using …

The Economic Impacts Of Blackbird (Icteridae) Damage To Sunflower In The Usa, Karina Ernst, Julie Elser, George Linz, Hans Kandel, Jason Holderieath, Samantha Degroot, Steven Shwiff, Stephanie Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

BACKGROUND: Blackbird (Icteridae) damage to ripening sunflower (Helianthus annuus L.) has been a persistent economic issue in the USA for the last five decades. To quantify losses, we surveyed blackbird damage from 2001 to 2013 (excluding 2004) to physiologically mature sunflower in eight states: North Dakota, South Dakota, Texas, Nebraska, Minnesota, Colorado, Kansas, and Vermont.

RESULTS:We pooled data gathered during the most recent 5 years (2009 to 2013) of the survey and found losses averaged $US2.5 million and $US11.3 million for confectionery and oilseed hybrids, respectively. Three states, North Dakota, South Dakota, and Nebraska, had sufficient acreage and bird damage …

Habitat Selection By American Beaverat Multiple Spatial Scales, Guiming Wang, Lance F. Mcclintic, Jimmy D. Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Semiaquatic mammals require both aquatic and terrestrial habitats, particularly interfaces between the two habitats. As ecosystem engineers, American beaver (Castor canadensis) consume and fell a great amount of deciduous trees. We tested the prediction that open water and amounts of food resources, including hardwood forests (i.e., deciduous trees as the dominant form of vegetation), herbaceous and woody wetlands, and shrubs, would influence the second-order habitat selection (i.e., placing home ranges on the landscape) by American beaver, whereas the third-order habitat selection of American beaver would be associated with woody wetland and shrub edges. We investigated hierarchical habitat selection by …

Epidemic Growth Rates And Host Movement Patterns Shape Management Performance For Pathogen Spillover At The Wildlife–Livestock Interface, Kezia R. Manlove, Laura M. Sampson, Benny Borremans, E. Frances Cassirer, Ryan S. Miller, Kim M. Pepin, Thomas E. Besser, Paul C. Cross

United States Department of Agriculture Wildlife Services: Staff Publications

Managing pathogen spillover at the wildlife–livestock interface is a key step towards improving global animal health, food security and wildlife conservation. However, predicting the effectiveness of management actions across host–pathogen systems with different life histories is an on-going challenge since data on intervention effectiveness are expensive to collect and results are system-specific.We developed a simulation model to explore how the efficacies of different management strategies vary according to host movement patterns and epidemic growth rates. The model suggested that fast-growing, fast-moving epidemics like avian influenza were best-managed with actions like biosecurity or containment, which limited and localized overall spillover risk. …

Board Invited Review: Prospects For Improving Management Of Animal Disease Introductions Using Disease-Dynamic Models, Ryan S. Miller, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Management and policy decisions are continually made to mitigate disease introductions in animal populations despite often limited surveillance data or knowledge of disease transmission processes. Science-based management is broadly recognized as leading to more effective decisions yet application of models to actively guide disease surveillance and mitigate risks remains limited. Disease-dynamic models are an efficient method of providing information for management decisions because of their ability to integrate and evaluate multiple, complex processes simultaneously while accounting for uncertainty common in animal diseases. Here we review disease introduction pathways and transmission processes crucial for informing disease management and models at the …

Improving Risk Assessment Of The Emergence Of Novel Influenza A Viruses By Incorporating Environmental Surveillance, Kim M. Pepin, Matthew W. Hopken, Susan A. Shriner, Erica Spackman, Zaid Abdo, Colin Parrish, Steven Steven, James O. Lloyd-Smith, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Reassortment is an evolutionary mechanism by which influenza A viruses (IAV) generate genetic novelty. Reassortment is an important driver of host jumps and is widespread according to retrospective surveillance studies.However, predicting the epidemiological risk of reassortant emergence in novel hosts from surveillance data remains challenging. IAV strains persist and cooccur in the environment, promoting co-infection during environmental transmission. These conditions offer opportunity to understand reassortant emergence in reservoir and spillover hosts. Specifically, environmental RNA could provide rich information for understanding the evolutionary ecology of segmented viruses, and transform our ability to quantify epidemiological risk to spillover hosts. However, significant challenges …

Injury Scores And Spatial Responses Of Wolves Following Capture: Cable Restraints Versus Foothold Traps, Eric M. Gese, Patricia A. Terletzky, John D. Erb, Kevin C. Fuller, Jeffery P. Grabarkewitz, John P. Hart, Carolin Humpal, Barry A. Sampson, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Wolves (Canis lupus) have been captured with foothold traps for several decades to equip them with radiocollars for population monitoring. However, trapping in most areas is limited to spring, summer, and autumn as cold winter temperatures can lead to frozen appendages in trapped animals. In addition, conflicts arise when domestic dogs encounter these traps in nonwinter seasons. An alternative capture method is the use of cable restraint devices (modified neck snares) in the winter. We evaluated injury scores, movement patterns, and space use of wolves captured in cable restraint devices and foothold traps in north central Minnesota, USA, during 2012–2016. …

Assessing Public Support For Restrictions On Transport Of Invasive Wild Pigs (Sus Scrofa) In The United States, Meredith J. Grady, Erin E. Harper, Keith M. Carlisle, Karina H. Ernst, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are a non-native invasive species in the United States that cause significant economic loss, transmit disease, and inflict damage upon natural resources, agriculture, livestock, and property. Geographic distribution of wild pigs in the United States has nearly tripled since 1982, with anthropogenic influences playing a significant role in the expansion. In this regard, there is speculation that a driver of the expansion may be human-mediated movement of wild pigs to new areas for the purpose of sport hunting. In response, states have implemented a variety of wild pig control policies, including legal restrictions on their transport. …

Invasive Feral Swine Damage To Globally Imperiled Steephead Ravine Habitats And Influences From Changes In Population Control Effort, Climate, And Land Use, Richard M. Engeman, Erica Laine, John Allen, Jeremy Preston, William Pizzolato, Brett Williams, Amanda Stevens Kreider, Dennis Teague

United States Department of Agriculture Wildlife Services: Staff Publications

Steephead ravines are unusual geological features primarily occurring in Florida’s panhandle, a biodiversity hotspot. The unique habitats formed by steepheads are extremely valuable biodiversity resources within this larger area of great biodiversity. Eglin Air Force Base (EAFB) is essential for global conservation of steepheads because this vast area holds the greatest number under single ownership. Steepheads are significantly threatened by feral swine rooting damage. A decade-long investigation of EAFB’s steepheads assessed the following: (1) severity of swine damage to steepheads, (2) changing levels of swine control on swine population and damage, (3) changing climatic conditions on damage, (4) changing military …

Behavioral Flexibility Of A Generalist Carnivore, Sarah E. Daniels, Rachel E. Fanelli, Amy Gilbert, Sarah Sarah Benson‑Amram

United States Department of Agriculture Wildlife Services: Staff Publications

Innovative problem solving, repeated innovation, learning, and inhibitory control are cognitive abilities commonly regarded as important components of behaviorally flexible species. Animals exhibiting these cognitive abilities may be more likely to adapt to the unique demands of living in novel and rapidly changing environments, such as urbanized landscapes. Raccoons

(Procyon lotor) are an abundant, generalist species frequently found in urban habitats, and are capable of innovative problem solving, which makes them an ideal species to assess their behavioral flexibility. We gave 20 captive raccoons a multi-access puzzle box to investigate which behavioral and cognitive mechanisms enable the generation …

The Past And Future Roles Of Competition And Habitat In The Range-Wide Occupancy Dynamics Of Northern Spotted Owls, Charles B. Yackulic, Larissa L. Bailey, Katie M. Dugger, Raymond J. Davis, Alan B. Franklin, Eric D. Forsman, Steven H. Ackers, Lawrence S. Andrews, Lowell V. Diller, Scott A. Gremel, Keith A. Hamm, Dale R. Herter, J. Mark Higley, Rob B. Horn, Christopher Mccafferty, Janice A. Reid, Jeremy T. Rockweit, Stan G. Sovern

United States Department of Agriculture Wildlife Services: Staff Publications

Slow ecological processes challenge conservation. Short-term variability can obscure the importance of slower processes that may ultimately determine the state of a system. Furthermore, management actions with slow responses can be hard to justify. One response to slow processes is to explicitly concentrate analysis on state dynamics. Here, we focus on identifying drivers of Northern Spotted Owl (Strix occidentalis caurina) territorial occupancy dynamics across 11 study areas spanning their geographic range and forecasting response to potential management actions. Competition with Barred Owls (Strix varia) has increased Spotted Owl territory extinction probabilities across all study areas and driven recent declines in …

Individual-Level Antibody Dynamics Reveal Potential Drivers Of Influenza A Seasonality In Wild Pig Populations, Kim M. Pepin, Kerri Pedersen, Xiu-Feng Wan, Fred L. Cunningham, Colleen T. Webb, Mark Q. Wilber

United States Department of Agriculture Wildlife Services: Staff Publications

Swine are important in the ecology of influenza A virus (IAV) globally. Understanding the ecological role of wild pigs in IAV ecology has been limited because surveillance in wild pigs is often for antibodies (serosurveillance) rather than IAVs, as in humans and domestic swine. As IAV antibodies can persist long after an infection, serosurveillance data are not necessarily indicative of current infection risk. However, antibody responses to IAV infections cause a predictable antibody response, thus time of infection can be inferred from antibody levels in serological samples, enabling identification of risk factors of infection at estimated times of infection. Recent …

Evaluation Of Two Unmanned Aircraft Systems As Tools For Protecting Crops From Blackbird Damage, Lucas J. Wandrie, Page E. Klug, Mark E. Clark

United States Department of Agriculture Wildlife Services: Staff Publications

In response to a need for mitigating blackbird damage to crops, we evaluated the effectiveness of two unmanned aircraft systems (UAS or drones) to protect crops from blackbird damage. UAS are known to elicit behavioral and physiological responses in wildlife and have been proposed as a means to protect row crop agriculture from avian pest depredation. We evaluated the behavioral responses of captive and free-ranging red-winged blackbirds to a fixed-wing and a rotary-wing (multi-rotor, quadcopter) UAS by comparing preflight behaviors to behaviors during UAS approach. Due to the flight limitations of the respective UAS, the fixed-wing and rotarywing were evaluated …

Locating And Eliminating Feral Swine From A Large Area Of Fragmented Mixed Forest And Agriculture Habitats In North-Central Usa, Richard M. Engeman, Bradley E. Wilson, Scott F. Beckerman, Justin W. Fischer, Doug Dufford, James Bryan Cobban

United States Department of Agriculture Wildlife Services: Staff Publications

Illinois is one of the US states where elimination of feral swine (Sus scrofa) was determined practical, as only a few isolated populations were established. A particularly important step towards feral swine elimination from Illinois was to eliminate the population in Fulton County. We describe the approaches applied to systematically detect, locate, and eliminate feral swine in a successful county-wide elimination. Detecting and locating feral swine was facilitated by extensive outreach activities, aerial surveys to locate crop damage, and use of camera traps placed over bait in areas where reports, sign, or crop damage occurred. The population was …

Road Hogs: Implications From Gps Collared Feral Swine In Pastureland Habitat On The General Utility Of Road-Based Observation Techniques For Assessing Abundance, Raoul K. Boughton, Benjamin L. Allen, Eric A. Tillman, Samantha M. Wisely, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine are among the world’s most destructive invasive species, and monitoring their populations is essential for research and management purposes. Observation stations located along primitive roads have been an efficient and effective means to intercept the daily activities of many animal species for collecting data from which abundance indices can be validly calculated. Feral swine are among the many species documented to use primitive (dirt), low-use roads as routes to easily traverse surrounding habitats and thus be well-monitored in various habitats globally by using road-based observation stations such as camera traps or tracking plots. However, there are relatively few …

Using Dna To Identify The Source Of Invasive Mongooses, Herpestes Auropunctatus (Carnivora: Herpestidae) Captured On Kaua‘I, Hawaiian Islands, Darren J. Wostenberg, Matthew W. Hopken, Aaron B. Shiels, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Two small Indian mongooses (Herpestes auropunctatus) were live-captured in 2012 at separate locations on the Hawaiian Island of Kaua'i, which was previously considered to be free of this invasive species. Genotypes from these two individuals were compared to genotypes of H. auropunctatus from the islands of Hawai'i (n =39), O'ahu (n =91), Maui (n = 39), and Moloka'i (n = 19) to determine the island of origin of the Kaua'i individuals. Genotypes were generated from each individual using five microsatellite loci. Genetic clustering was estimated by Bayesian inference of spatial clustering of individuals and …

Reducing Prairie Dog Populations And Damage By Castration Of Dominant Males, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Black-tailed prairie dogs (Cynomys ludovicianus) occur widely across the prairie states of North America. They compete with livestock for forage, transmit plague, and damage lawns, landscaping, and property. Interest in non-lethal methods, such as immunocontraception, is growing; however, reductions in the population due to contraception may be offset by increases in survival because adults and yearlings are not subject to the energetic demands of reproduction, and lower densities may increase the amount of resources available to growing offspring. Surgical sterilization provides a means for modeling these effects. Thus, we castrated males prior to the 1998 breeding season to simulate the …

Parasitism, Host Behavior, And Invasive Species, Sarah N. Bevins

United States Department of Agriculture Wildlife Services: Staff Publications

Animal behavior and parasitism are inextricable linked. In many cases, host behavior can affect what parasites are encountered. In other cases, parasites can manipulate the behavior of the host in an attempt to maximize their own transmission. These long-standing interactions are now further complicated by species movement around the globe. The list of introduced species that have become invasive includes parasites that have adapted to new hosts in areas of introduction, as well as invasive hosts that alter the association between existing parasite–host assemblages. Researchers have documented differences in rates of parasitism and in the consequences of parasite infection between …

Necrobiome Framework For Bridging Decomposition Ecology Of Autotrophically And Heterotrophically Derived Organic Matter, Mark Eric Benbow, Philip S. Barton, Michael D. Ulyshen, James C. Beasley, Travis L. Devault, Michael S. Strickland, Jeffery K. Tomberlin, Heather R. Jordan, Jennifer L. Pechal

United States Department of Agriculture Wildlife Services: Staff Publications

Life arises from death through species that decompose dead biomass or necromass. This paper provides a synthesis of the species responsible for dead plant and animal decomposition and describes a conceptual perspective—the “necrobiome”— that defines the diverse and complex communities that interact to recycle necromass. The concept brings unification to the previously disparate fields of plant and animal decomposition by discussing the universal processes occurring across all forms of necromass. It highlights the factors that make each form of dead biomass different in a way that defines how unique necrobiomes drive decomposition and ultimately shape ecosystem structure and function.

Allowable Take Of Black Vultures In The Eastern United States, Guthrie Zimmerman, Brian A. Millsap, Michael L. Avery, John R. Sauer, Michael C. Runge, Kenneth D. Richkus

United States Department of Agriculture Wildlife Services: Staff Publications

Black vultures (Coragyps atratus) have been increasing in density and expanding their range in the eastern United States since at least the 1960s. In many areas, their densities have increased to the level where they are causing damage to property and livestock and the number of requests for allowable take permits has increased throughout these areas. The United States Fish and Wildlife Service (USFWS) requires updated information to help inform the number of take permits that could reduce conflicts while meeting obligations under the Migratory Bird Treaty Act.We expanded analyses used to estimate allowable take in Virginia to …