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Estimates Of Small Indian Mongoose Densities: Implications For Rabies Management, Shylo R. Johnson, Are R. Berentsen, Christine Ellis, Amy Davis, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

The small Indian mongoose (Herpestes auropunctatus) is an invasive species and rabies reservoir in Puerto Rico. In the continental United States, terrestrial wildlife rabies is primarily managed by the National Rabies Management Program (NRMP) of the United States Department of Agriculture through oral rabies vaccination (ORV); the distribution of the vaccine baits is influenced by the population density of the target species. TheNRMPuses a density index for estimating raccoon (Procyon lotor) population density to guide bait distribution. In Puerto Rico, a wildlife rabies vaccination program does not exist and vaccination of domestic animals is limited and not compulsory. …

Bait Preference Of Free-Ranging Feral Swine For Delivery Of A Novel Toxicant, Nathan P. Snow, Joseph M. Halseth, Michael J. Lavelle, Thomas E. Hanson, Chad R. Blass, Justin A. Foster, Simon T. Humphrys, Linton D. Staples, David G. Hewitt, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive feral swine (Sus scrofa) cause extensive damage to agricultural and wildlife resources throughout the United States. Development of sodium nitrite as a new, orally delivered toxicant is underway to provide an additional tool to curtail growth and expansion of feral swine populations. A micro-encapsulation coating around sodium nitrite is used to minimize detection by feral swine and maximize stability for the reactive molecule. To maximize uptake of this toxicant by feral swine, development a bait matrix is needed to 1) protect the micro-encapsulation coating so that sodium nitrite remains undetectable to feral swine, 2) achieve a high …

Evaluation Of Harvest Indices For Monitoring Cougar Survival And Abundance, Michael L. Wolfe, Eric M. Gese, Pat Terletzky, David C. Stoner, Lise M. Aubry

United States Department of Agriculture Wildlife Services: Staff Publications

Harvest indices are used by state wildlife management agencies to monitor population trends and set harvest quotas for furbearer species. Although harvest indices may be readily collected from hunters, the reliability of harvest indices for monitoring demography and abundance of the harvested species is rarely examined, particularly amongst large carnivores. The overall objective of this study was to assess whether cougar (Puma concolor) harvest statistics collected by wildlife managers were correlated with changes in cougar demography, mainly survival rates and abundance. We estimated key demographic parameters for 2 cougar populations in Utah over 17 years during which we monitored 235 …

Cholecalciferol Plus Diphacinone Baits For Vole Control: A Novel Approach To A Historic Problem, Roger A. Baldwin, Ryan Meinerz, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Combination baits containing cholecalciferol plus an anticoagulant are effective against commensal rodents resistant to anticoagulants, and they likely pose less risk than anticoagulant-only rodenticides due to lower concentrations of active ingredients and shorter time to death. However, these combination baits have not been tested for agricultural rodent pests. Therefore, we established a study to test the efficacy of cholecalciferol plus diphacinone artichoke bract and pellet baits to determine their ability to manage California voles Microtus californicus in artichokes, where resistance to anticoagulants is known to occur. Field tests using radiocollared voles indicated that bract baits were highly efficacious (85 %), …

Defending Against Disparate Marine Turtle Nest Predators: Nesting Success Benefits From Eradicating Invasive Feral Swine And Caging Nests From Raccoons, Richard M. Engeman, David Addison, J. C. Griffin

United States Department of Agriculture Wildlife Services: Staff Publications

Nest predation can threaten marine turtle nesting success, and having to address dissimilar predator species complicates nest protection efforts. On Florida’s Keewaydin Island predation by raccoons Procyon lotor and invasive feral swine Sus scrofa are disparate, significant threats tomarine turtle nests. Using 6 years of nesting data (mostly for loggerhead marine turtles Caretta caretta) we examined the impacts of swine predation on nests and the benefits of swine eradication, caging nests to protect them from raccoon predation, and the effects of nest caging on swine predation. Nest predation by swine began in mid nesting season 2007, after which swine …

Evaluation Of An Avian Radar System In A Midwestern Landscape, Michael B. Gerringer, Steven L. Lima, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Bird strikes in aviation are an increasing threat to both aircraft and human safety. Management efforts have focused largely on the immediate airport environment. Avian radar systems could potentially be useful in assessing bird strike threats at greater distances from the airport, at higher altitudes, and at night, but few studies have been conducted to assess the capabilities of avian radar systems. Thus, our goal was to assess the detection and tracking abilities of a commercially available avian radar system in an airport environment in Indiana, USA, during October 2011–March 2012. Transits by free-flying birds allowed us to assess radar …

Development Of Artificial Bait For Brown Treesnake Suppression, Bruce A. Kimball, Scott A. Sterling, Thomas W. Mcauliffe, Randal S. Stahl, Rafael A. Garcia, William C. Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

The brown treesnake (Boiga irregularis) was accidentally introduced to Guam in the 1940s from the Admiralty Islands. A native of Australia, Papua New Guinea, and the Solomon Islands, the brown treesnake (BTS) continues to threaten the economy and ecology of Guam and is currently the subject of a cooperative program to control snake populations on the island and prevent its spread throughout the Pacific Rim. Delivery of toxic baits is a primary component of population suppression efforts. While many food items tested as baits for toxicant delivery provide relevant food prey cues leading to investigatory behaviors in BTS, …

Retention Time Of Chlorophacinone In Black-Tailed Prairie Dogs Informs Secondary Hazards From A Prairie Dog Rodenticide Bait, Gary W. Witmer, Nathan P. Snow, Rachael S. Moulton

United States Department of Agriculture Wildlife Services: Staff Publications

BACKGROUND: Secondary toxicity in mammals and birds that consume animals containing residues of anticoagulant rodenticides represents a persistent conflict between conservation, agriculture and environmental contamination. Chlorophacinone residues in black-tailed prairie dogs (Cynomys ludovicianus) represent a secondary exposure hazard to predatory and scavenging avian and mammalian species in the Central Plains of the United States, especially considering efforts to re-establish black-footed ferrets (Mustela nigripes). Rozol® Prairie Dog Bait (chlorophacinone 0.005%) is registered to control black-tailed prairie dogs in ten states throughout themidwestern and western United States.

RESULTS:We fed Rozol Prairie Dog Bait to captive black-tailed prairie dogs …

Susceptibility Of Rock Doves To Low-Pathogenic Avian Influenza A Viruses, Susan A. Shriner, J. Jeffrey Root, Nicole L. Mooers, Jeremy W. Ellis, Scott R. Stopak, Heather J. Sullivan, Kaci K. Vandalen, Alan B. Franklin

United States Department of Agriculture Wildlife Services: Staff Publications

Following a 2008 outbreak of North American low-pathogenic H5N8 influenza A virus at an upland gamebird farm, we sero-sampled rock doves (pigeons, Columba livia) at the outbreak site and conducted experimental inoculations of wild-caught pigeons using the H5N8 virus and another low-pathogenic virus (H4N6). While 13 % of pigeons at the outbreak site were seropositive, none were positive for exposure to H5, and one was positive for N8. Challenged pigeons exhibited low susceptibility and limited viral RNA excretion for both viruses tested, but at least one individual had RNA loads indicative of the potential for viral transmission to other …

Fishing Diseased Abalone To Promote Yield And Conservation, Tal Ben-Horin, Kevin D. Lafferty, Gorka Bidegain, Hunter S. Lenihan

United States Geological Survey: Staff Publications

Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease- fishing models, we modelled targeting (culling) infected individuals,which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to …

Supplementary Feeding And Endangered Avian Scavengers: Benefits, Caveats, And Controversies, Ainara Cortés- Avizanda, Guillermo Blanco, Travis L. Devault, Anil Markandya, Munir Z Virani, Joseph Brandt, José A Donázar

United States Department of Agriculture Wildlife Services: Staff Publications

Large avian scavengers are among the most vulnerable vertebrates, and many of their populations have declined severely in recent decades. To help mitigate this marked reduction in abundance, supplementary feeding stations (SFS; colloquially termed “vulture restaurants”) have been created worldwide, often without consideration of the scientific evidence supporting the suitability of the practice. SFS have been effective and important tools for conservation and reintroduction of avian scavengers. However, negative consequences can result from large aggregations of individual birds, disrupting intraguild processes and promoting density-dependent decreases in productivity. At the community level, SFS favor the congregation of predators (ie facultative scavengers), …

American Robins (Turdus Migratorius) And Cedar Waxwings (Bombycilla Cedrorum) Vary In Use Of Cultivated Cherry Orchards, Rachael A. Eaton, Catherine A. Lindell, Jeffrey Homan, George M. Linz, Brian A. Maurer

United States Department of Agriculture Wildlife Services: Staff Publications

Some fruit-eating bird species commonly consume cultivated fruit. Species-specific variation in diet preferences could result in varying use of orchards and impacts on the fruit-producing industry. However, species specific studies of avian orchard use are lacking, particularly throughout the fruit-growing season. Our objectives were to quantify the frequency of daily bird visits to orchards and the amount of time birds spent visiting orchards each day over the fruit-ripening season. Birds are well-documented consumers of cultivated sweet cherries (Prunus avium), which are relatively high in sugar and low in proteins and lipids. American Robins (Turdus migratorius) and …

Disease-Emergence Dynamics And Control In A Socially-Structured Wildlife Species, Kim M. Pepin, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Once a pathogen is introduced in a population, key factors governing rate of spread include contact structure, supply of susceptible individuals and pathogen life-history. We examined the interplay of these factors on emergence dynamics and efficacy of disease prevention and response. We contrasted transmission dynamics of livestock viruses with different life-histories in hypothetical populations of feral swine with different contact structures (homogenous, metapopulation, spatial and network). Persistence probability was near 0 for the FMDV-like case under a wide range of parameter values and contact structures, while persistence was probable for the CSFV-like case. There were no sets of conditions where …

Limited Transmission Of Emergent H7n9 Influenza A Virus In A Simulated Live Animal Market: Do Chickens Pose The Principal Transmission Threat?, Angela Bosco-Lauth, Richard A. Bowen, J. Jeffrey Root

United States Department of Agriculture Wildlife Services: Staff Publications

Emergent H7N9 influenza A virus has caused multiple public health and financial hardships. While some epidemiological studies have recognized infected chickens as an important bridge for human infections, the generality of this observation, the minimum infectious dose, and the shedding potential of chickens have received conflicting results. We experimentally tested the ability of domestic chickens (Gallus gallus domesticus) to transmit H7N9 to co-housed chickens and to several other animal species in an experimental live animal market. Results indicated that an infected chicken failed to initiate viral shedding of H7N9 to naIve co-housed chickens. The infected chicken did, however, …

High Rates Of Detection Of Clade 2.3.4.4 Highly Pathogenic Avian Influenza H5 Viruses In Wild Birds In The Pacific Northwest During The Winter Of 2014–15, Hon S. Ip, Robert J. Dusek, Barbara Bodenstein, Mia Kim Torchetti, Paul Debruyn, Kristin Mansfield, Thomas J. Deliberto, Jonathan M. Sleeman

United States Department of Agriculture Wildlife Services: Staff Publications

SUMMARY. In 2014, clade 2.3.4.4 H5N8 highly pathogenic avian influenza (HPAI) viruses spread across the Republic of Korea and ultimately were reported in China, Japan, Russia, and Europe. Mortality associated with a reassortant HPAI H5N2 virus was detected in poultry farms in western Canada at the end of November. The same strain (with identical genetic structure) was then detected in free-living wild birds that had died prior to December 8, 2014, of unrelated causes in Whatcom County, Washington, U. S. A., in an area contiguous with the index Canadian location. A gyrfalcon (Falco rusticolus) that had hunted and …

Outbreak Of H7n8 Low Pathogenic Avian Influenza In Commercial Turkeys With Spontaneous Mutation To Highly Pathogenic Avian Influenza, Mary Lea Killian, Mia Kim Torchetti, Nichole Hines, Sam Yingst, Thomas J. Deliberto, Dong-Hun Lee

United States Department of Agriculture Wildlife Services: Staff Publications

Highly pathogenic avian influenza (HPAI) subtype H7N8 was detected in commercial turkeys in January 2016. Control zone surveillance discovered a progenitor low pathogenic avian influenza (LPAI) virus in surrounding turkey flocks. Data analysis supports a single LPAI virus introduction followed by spontaneous mutation to HPAI on a single premises.

Highly Pathogenic Avian Influenza Viruses And Generation Of Novel Reassortants, United States, 2014–2015, Dong-Hun Lee, Justin Bahl, Mia Kim Torchetti, Mary Lea Killian, Hon S. Ip, Thomas J. Deliberto, David E. Swayne

United States Department of Agriculture Wildlife Services: Staff Publications

Asian highly pathogenic avian influenza A(H5N8) viruses spread into North America in 2014 during autumn bird migration. Complete genome sequencing and phylogenetic analysis of 32 H5 viruses identified novel H5N1, H5N2, and H5N8 viruses that emerged in late 2014 through reassortment with North American low-pathogenicity avian influenza viruses.

A Noninvasive Method To Detect Mexican Wolves And Estimate Abundance, Antoinette J. Piaggio, Chip.A. Cariappa, Dyan J. Straughan, Melissa Neubaum, Margaret Dwire, Paul R. Krausman, Warren B. Ballard, David L. Bergman, Stewart W. Breck

United States Department of Agriculture Wildlife Services: Staff Publications

Monitoring wolf abundance is important for recovery efforts of Mexican wolves (Canis lupus baileyi) in the Blue Range Wolf Recovery Area in Arizona and New Mexico, USA. Although radiotelemetry has been a reliable method, collaring and tracking wolves in an expanding population will be prohibitively expensive and alternative methods to estimate abundance will become necessary. We applied 10 canid microsatellite loci to 235 Mexican wolf samples, 48 coyote (C. latrans) samples, and 14 domestic dog (C. lupus familiaris) samples to identify alleles that provide reliable separation of these species. We then evaluated an approach …

Ecosystem Services Provided By Avian Scavengers, Travis L. Devault, James C. Beasley, Zachary H. Olson, Marcos Moleón, Martina Carrete, Antoni Margalida, José Antonio Sánchez-Zapata

United States Department of Agriculture Wildlife Services: Staff Publications

Food webs developed under classical theoretical models often depict simplistic interactions among trophic levels linked by predation (Hairston et al. 1960). As a result, extensive research efforts have been devoted to studying predator-prey interactions, often ignoring the contribution of scavenging in food-web dynamics. However, recent advancements in food-web theory have recognized the widespread and critical role that scavenging plays in stabilizing food webs in ecosystems throughout the world, thus suggesting that previous models may have greatly underestimated the importance of scavenging in food web research ( Wilson and Wolkovich 2011; Barton et al. 2013). Such disregard for the importance of …

Evaluation Of A Food Bait Block For Potential Chemical Delivery To Black-Tailed Prairie Dogs (Cynomys Ludovicianus), Gary W. Witmer, Rachael S. Moulton, Jenna L. Swartz

United States Department of Agriculture Wildlife Services: Staff Publications

Fertility control is a potential method to control prairie dog populations in the urban/suburban environment. However, an effective, oral delivery system is needed. We tested a food bait block delivery system that could make baits available to prairie dogs over a number of days which would make this method more cost-effective than placing food bait by hand near burrows every day. Prairie dogs readily consumed the bait blocks stacked on vertical metal poles during the day. We found, however, that rabbits and mice also consumed the food bait blocks, mainly at night. Over the course of the study, the mean …

Resource Selection By Cougars: Influence Of Behavioral State And Season, Linsey W. Blake, Eric M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

An understanding of how a predator uses the landscape can assist in developing management plans. We modeled resource selection by cougars (Puma concolor) during 2 behavioral states (moving and killing) and 2 seasons (summer and winter) with respect to landscape characteristics using locations from global positioning system (GPS)-collared cougars in the Pryor Mountains, Montana and Wyoming, USA. Furthermore, we examined predation-specific resource selection at 2 scales (fine and coarse). When possible, we backtracked from cache sites to kill sites and used a fine-scale analysis to examine landscape characteristics of confirmed kills. At this fine scale, kill sites had …

Proportions Of Bird Damage In Tree Fruits Are Higher In Low-Fruit-Abundance Contexts, Catherine A. Lindell, Karen M.M. Steensma, Paul D. Curtis, Jason R. Boulanger, Juliet E. Carroll, Colleen Burrows, David P. Lusch, Nikki L. Rothwell, Shayna L. Wieferich, Heidi M. Henrichs, Deanna K. Leigh, Rachael A. Eaton, George M. Linz

United States Department of Agriculture Wildlife Services: Staff Publications

Frugivorous birds impose significant costs on tree fruit growers through direct consumption of fruit and grower efforts to manage birds.We documented factors that influenced tree fruit bird damage from 2012 through 2014 with a coordinated field study in Michigan, New York, and Washington. For sweet cherries, percent bird damage was higher in 2012 compared to 2013 and 2014, in Michigan and New York compared toWashington, and in blocks with more edges adjacent to non-sweet cherry land-cover types. These patterns appeared to be associated with fruit abundance patterns; 2012 was a particularly lowyield year for tree fruits in Michigan and New …

Identification Of Robust Microsatellite Markers For Wild Pig Fecal Dna, Elizabeth M. Kierepka, Shem D. Unger, David A. Keiter, James C. Beasley, Olin E. Rhodes Jr., Fred L. Cunningham, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Collection of fecal samples for use in a genetic capture-mark-recapture framework has become popular as a noninvasive method of monitoring wildlife populations. A major caveat to this process, however, is that fecal samples often yield low quality DNA that is prone to genotyping errors, potentially leading to biases in population parameter estimation. Therefore, considerable care is required to identify robust genetic markers, especially in hot or humid conditions that may accelerate DNA degradation. We identified microsatellite loci in wild pig (Sus scrofa) fecal samples that were robust and informative within warm, humid ecosystems. To examine how degradation affected …

Feral Swine Damage To Globally Imperiled Wetland Plant Communities In A Significant Biodiversity Hotspot In Florida, Richard M. Engeman, Steve L. Orzell, Rodney K. Felix, Eric A. Tillman, Gary Killian, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

We studied rooting damage during five-years of feral swine control at Avon Park Air Force Range, a significant botanical biodiversity hotspot in peninsular Florida with many globally imperiled plant species and communities. While control reduced swine abundance, remaining animals consistently rooted the 49 studied sites in both middle-dry season (MDS) and late-dry season (LDS) each year. At each study site, we measured rooting with sub-meter accuracy. Neither total nor proportional area rooted differed in either season, across study years, or among plant community types: herbaceous seepage slopes, wet pine savannas, wet grasslands. The proportion of sites with damage during MDS …

Olfactory Attractants And Parity Affect Prenatal Androgens And Territoriality Of Coyote Breeding Pairs, Christopher J. Schell, Julie K. Young, Elizabeth V. Lonsdorf, Jill M. Mateo, Rachel M. Santymire

United States Department of Agriculture Wildlife Services: Staff Publications

Hormones are fundamental mediators of personality traits intimately linked with reproductive success. Hence, alterations to endocrine factors may dramatically affect individual behavior that has subsequent fitness consequences. Yet it is unclear how hormonal or behavioral traits change with environmental stressors or over multiple reproductive opportunities, particularly for biparental fauna. To simulate an environmental stressor, we exposed captive coyote (Canis latrans) pairs to novel coyote odor attractants (i.e. commercial scent lures) midgestation to influence territorial behaviors, fecal glucocorticoid (FGMs) and fecal androgen metabolites (FAMs). In addition, we observed coyote pairs as first-time and experienced breeders to assess the influence …

Evaluation Of Boldness Assays And Associated Behavioral Measures In A Social Parrot, Monk Parakeet (Myiopsitta Monachus), Kaan Kerman, Kathryn E. Sieving, Colette S. Mary, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

Boldness reflects consistent individual differences in risk-taking behavior across various contexts. However, evaluating this basic assumption has largely been neglected in birds. In a captive monk parakeet population (Myiopsitta monachus; N = 33), we undertook an analysis of 7 measures across 3 commonly used boldness assays (i.e., novel object, emergence, and predator-exposure tests). Using principal component analysis, we derived 3 components (PCs). PC-2 loaded strongly with measures from emergence and predator-exposure tests; we interpreted it as the closest approximation of boldness. PC-1 and PC-3 described different aspects of feeding such as foraging activity and rate, respectively. Finally, we …

Winter And Summer Home Ranges Of American White Pelicans (Pelecanus Erythrorhynchos) Captured At Loafing Sites In The Southeastern United States, D. Tommy King, Justin W. Fischer, Bronson Strickland, W. David Walter, Fred L. Cunningham, Guiming Wang

United States Department of Agriculture Wildlife Services: Staff Publications

Satellite telemetry was used to investigate summer and winter home ranges for resident and migrant American White Pelicans (Pelecanus erythrorhynchos) captured in the southeastern United States between 2002 and 2007. Home range utilization distributions were calculated using 50% and 95% kernel density estimators with the plug-in bandwidth selector. Mean summer home ranges (95%) varied from 177 to 4,710 km2 and mean winter home ranges (95%) ranged from 185 to 916 km2. Mean 50% and 95% home ranges of adult American White Pelicans during summer tended to be larger than those during winter, whereas mean 50% and 95% home …

Environmental Factors Influencing The Occurrence Of Coyotes And Conflicts In Urban Areas, Sharon A. Poessel, Eric M. Gese, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

The increase of global urbanization can have effects on wildlife species, including carnivores such as coyotes (Canis latrans). As coyotes continue to settle in more urban areas, reports of human-coyote conflicts, such as attacks on humans or pets, may also increase. Understanding environmental variables that might influence whether or not coyotes and human-coyote conflicts will occur in certain urban areas may assist wildlife officials in creating management plans for urban wildlife.We conducted a survey of 105 urban areas in the United States requesting information on the occurrence of coyotes and human-coyote conflicts. We analyzed the responses with data …

Speed Kills: Effects Of Vehicle Speed On Avian Escape Behavior, Travis L. Devault, Bradley F. Blackwell, Thomas W. Seamans, Steven L. Lima, Esteban Fernández-Juricic

United States Department of Agriculture Wildlife Services: Staff Publications

The avoidance of vehicles is a common challenge for birds in the modern world. Birds generally rely on antipredator behaviors to avoid vehicles, but modern vehicles are faster than predators. We predicted that birds may be unable to accurately estimate the speed of approaching vehicles, which could contribute to miscalculations in avoidance behaviors and cause collisions. We tested our prediction in two studies. In the first (DeVault et al. 2014), we baited turkey vultures (Cathartes aura) to roads with animal carcasses and measured flight initiation distance (FID) when driving a truck towards them at 30, 60, or 90 …

Morphometric Variation During Chick Development In Interior Double-Crested Cormorants (Phalacrocorax Auritus), Jennifer E. Chastant, Corey T. Callaghan, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

In numerous avian species, egg size is correlated to female body condition, hatchling size and nestling growth. Recent demography studies of Interior Double-crested Cormorants (Phalacrocorax auritus) suggest a migratory divide across the Great Lakes; western populations winter in the Gulf of Mexico region of the southeastern United States (Alabama, Arkansas, Louisiana, and Mississippi) with extensive catfish (Ictalurus punctatus) aquaculture, and eastern populations winter in Florida, where catfish aquaculture is not pervasive. If Double-crested Cormorants have improved their overall body condition through catfish exploitation, then egg and chick sizes should also be affected. Three breeding areas in Ontario (east, central, and …