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An Evaluation Of Three Statistical Methods Used To Model Resource Selection, David M. Baasch, Andrew J. Tyre, Joshua J. Millspaugh, Scott E. Hygnstrom, Kurt C. Vercauteren 2010 University of Nebraska-Lincoln

An Evaluation Of Three Statistical Methods Used To Model Resource Selection, David M. Baasch, Andrew J. Tyre, Joshua J. Millspaugh, Scott E. Hygnstrom, Kurt C. Vercauteren

USDA National Wildlife Research Center - Staff Publications

The performance of statistical methods for modeling resource selection by animals is difficult to evaluate with field data because true selection patterns are unknown. Simulated data based on a known probability distribution, though, can be used to evaluate statistical methods. Models should estimate true selection patterns if they are to be useful in analyzing and interpreting field data. We used simulation techniques to evaluate the effectiveness of three statistical methods used in modeling resource selection. We generated 25 use locations per animal and included 10, 20, 40, or 80 animals in samples of use locations. To simulate species of different ...


Importance Of Resource Selection And Social Behavior To Partitioning Of Hostile Space By Sympatric Canids, Todd Atwood, Eric Gese 2010 USDA/APHIS/WS National Wildlife Research Center

Importance Of Resource Selection And Social Behavior To Partitioning Of Hostile Space By Sympatric Canids, Todd Atwood, Eric Gese

USDA National Wildlife Research Center - Staff Publications

Investigations into mechanisms of resource partitioning are particularly suited to systems where nascent interactive behaviors are observable. Wolf (Canis lupus) recolonization of the Greater Yellowstone Ecosystem provided such a system, and we were able to identify behaviors influencing the partitioning of resources by coyotes (Canis latrans) and wolves. We observed coyote–wolf interactions immediately after wolf recolonization, when reemergent behaviors mediating the outcome of competitive interactions were detectable and mechanisms of spatial avoidance were identifiable. Although coyotes used the same space as wolves, they likely minimized risk of encounter by making adaptive changes in resource selection based on perception of ...


Comparison Of Endocrine Response To Stress Between Captive-Raised And Wild-Caught Bighorn Sheep, Sarah Coburn, Mo Salman, Jack Rhyan, Thomas Keefe, Matthew McCollum, Keith Aune, Terry Spraker, Lowell Miller 2010 Colorado State University

Comparison Of Endocrine Response To Stress Between Captive-Raised And Wild-Caught Bighorn Sheep, Sarah Coburn, Mo Salman, Jack Rhyan, Thomas Keefe, Matthew Mccollum, Keith Aune, Terry Spraker, Lowell Miller

USDA National Wildlife Research Center - Staff Publications

Stress hormones in Rocky Mountain bighorn sheep (Ovis canadensis canadensis), produced in response to environmental changes, road development, or high population density, may impact their immune systems to a threshold level that predisposes them to periodic, large-scale mortality. We compared the stress response to a novel environmental situation and repeated handling between bighorn sheep born and raised in captivity (CR) and bighorn sheep born in the wild (WC) and brought into captivity. We measured plasma epinephrine, norepinephrine, cortisol, and fecal glucocorticoid metabolites (FGM). Three weeks after each group’s arrival we used a one-time drop-net event to elicit an acute ...


Experimental Infection Of Raccoons (Procyon Lotor) With West Nile Virus, J. Jeffrey Root, Kevin T. Bentler, Nicole M. Nemeth, Thomas Gidlewski, Terry R. Spraker, Alan B. Franklin 2010 USDA/APHIS/WS National Wildlife Research Center

Experimental Infection Of Raccoons (Procyon Lotor) With West Nile Virus, J. Jeffrey Root, Kevin T. Bentler, Nicole M. Nemeth, Thomas Gidlewski, Terry R. Spraker, Alan B. Franklin

USDA National Wildlife Research Center - Staff Publications

To characterize the responses of raccoons to West Nile virus (WNV) infection, we subcutaneously exposed them to WNV. Moderately high viremia titers (≤ 104.6 plaque forming units [PFU]/mL of serum) were noted in select individuals; however, peak viremia titers were variable and viremia was detectable in some individuals as late as 10 days post-inoculation (DPI). In addition, fecal shedding was prolonged in some animals (e.g., between 6 and 13 DPI in one individual), with up to105.0 PFU/fecal swab detected. West Nile virus was not detected in tissues collected on 10 or 16 DPI, and ...


Response Of Captive Skunks To Microencapsulated Tetracycline, Brandon S. Schmit, Thomas M. Primus, Jerome C. Hurley, Dennis J. Kohler, Shawna F. Graves 2010 USDA/APHIS/WS National Wildlife Research Center

Response Of Captive Skunks To Microencapsulated Tetracycline, Brandon S. Schmit, Thomas M. Primus, Jerome C. Hurley, Dennis J. Kohler, Shawna F. Graves

USDA National Wildlife Research Center - Staff Publications

A captive striped skunk (Mephitis mephitis) study was conducted between February and June 2004 at the United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services National Wildlife Research Center, Fort Collins, Colorado, USA. The main objective was to determine the percentage of adult striped skunks that were marked after consuming placebo oral rabies vaccine (ORV) baits containing 100 mg of an experimental microencapsulated (coated microparticle) tetracycline hydrochloride biomarker. Biomarkers were identified in the canine teeth and mandibles of five of five skunks that consumed an ORV bait. A second objective was to determine if the microencapsulated ...


Mite-Filled Cyst On A Brown-Headed Cowbird (Molothrus Ater) In Florida, Usa, Marilyn G. Spalding, James W. Mertins, Matthew J. Reetz, Kandy L. Keacher, Michael L. Avery, Ellis C. Greiner 2010 University of Florida

Mite-Filled Cyst On A Brown-Headed Cowbird (Molothrus Ater) In Florida, Usa, Marilyn G. Spalding, James W. Mertins, Matthew J. Reetz, Kandy L. Keacher, Michael L. Avery, Ellis C. Greiner

USDA National Wildlife Research Center - Staff Publications

A large, partly pedunculated mass on the scapular area of a wild-caught captive Brown-headed Cowbird (Molothrus ater) consisted of a multiloculated keratin cyst inhabited by a new species of harpirhynchid mite (Harpirhynchus quasimodo). The mass did not interfere with flight or behavior. This is the first record of such an infestation of cowbirds in Florida.


Foot-And-Mouth Disease In Feral Swine: Susceptibility And Transmission, F. Mohamed, S. Swafford, H. Petrowski, A. Bracht, B. S. Schmit, A. Fabian, J. M. Pacheco, E. Hartwig, M. Berninger, C. Carrillo, G. Mayr, K. Moran, D. Kavanaugh, H. Leibrecht, W. White, S. Metwally 2010 USDA, APHIS

Foot-And-Mouth Disease In Feral Swine: Susceptibility And Transmission, F. Mohamed, S. Swafford, H. Petrowski, A. Bracht, B. S. Schmit, A. Fabian, J. M. Pacheco, E. Hartwig, M. Berninger, C. Carrillo, G. Mayr, K. Moran, D. Kavanaugh, H. Leibrecht, W. White, S. Metwally

USDA National Wildlife Research Center - Staff Publications

Experimental studies of foot-and-mouth disease (FMD) in feral swine are limited, and data for clinical manifestations and disease transmissibility are lacking. In this report, feral and domestic swine were experimentally infected with FMDV (A24-Cruzeiro), and susceptibility and virus transmission were studied. Feral swine were proved to be highly susceptible to A-24 Cruzeiro FMD virus by intradermal inoculation and by contact with infected domestic and feral swine. Typical clinical signs in feral swine included transient fever, lameness and vesicular lesions in the coronary bands, heel bulbs, tip of the tongue and snout. Domestic swine exhibited clinical signs of the disease within ...


Evaluating Commercially Available Rodenticide Baits For Invasive Gambian Giant Pouched Rats (Cricetomys Gambianus), Gary W. Witmer, Nathan P. Snow, Patrick W. Burke 2010 USDA-APHIS-Wildlife Services

Evaluating Commercially Available Rodenticide Baits For Invasive Gambian Giant Pouched Rats (Cricetomys Gambianus), Gary W. Witmer, Nathan P. Snow, Patrick W. Burke

USDA National Wildlife Research Center - Staff Publications

Gambian giant pouched rats (Cricetomys gambianus) are native to Africa, but they are popular in the pet industry in the United States. They were reservoir hosts during a monkeypox outbreak in the Midwestern United States in 2003. A free-ranging population became established on Grassy Key in the Florida Keys, apparently because of a release by a pet breeder. These rodents could cause significant damage to agricultural crops should they reach the mainland. Research under controlled conditions was needed to identify effective rodenticides for Grassy Key or other cases where an invasion of Gambian rats might occur. We tested 2 formulations ...


New Evidence Suggests Southern China As A Common Source Of Multiple Clusters Of Highly Pathogenic H5n1 Avian Influenza Virus, Bin Wu, Chengmin Wang, Guoying Dong, Yunhai Guo, Dale L. Nolte, Thomas Jude Deliberto, Jianguo Xu, Mingxing Duan, Hongxuan He 2010 Institute of Zoology

New Evidence Suggests Southern China As A Common Source Of Multiple Clusters Of Highly Pathogenic H5n1 Avian Influenza Virus, Bin Wu, Chengmin Wang, Guoying Dong, Yunhai Guo, Dale L. Nolte, Thomas Jude Deliberto, Jianguo Xu, Mingxing Duan, Hongxuan He

USDA National Wildlife Research Center - Staff Publications

Highly pathogenic H5N1 avian influenza is considered an avian disease, although there is some evidence of limited human-to-human transmission of the virus. A global effort is underway to control or eradicate the highly pathogenic H5N1 avian influenza virus in poultry and prevent human exposure, both of which may also reduce the risk of pandemic emergence. Hemagglutinin gene sequences from 215 human H5N1 influenza viruses were used to trace the source and dispersal pattern of human H5N1 influenza viruses on a global scale. A mutation network and phylogenetic analyses of the hemagglutinin gene show that human H5N1 influenza viruses can be ...


Kill Rates And Predation Patterns Of Jaguars (Panthera Onca) In The Southern Pantanal, Brazil, Sandra M. C. Cavalcanti, Eric M. Gese 2010 Utah State University, Logan, Department of Wildland Resources,

Kill Rates And Predation Patterns Of Jaguars (Panthera Onca) In The Southern Pantanal, Brazil, Sandra M. C. Cavalcanti, Eric M. Gese

USDA National Wildlife Research Center - Staff Publications

Jaguars (Panthera onca) often prey on livestock, resulting in conflicts with humans. To date, kill rates and predation patterns by jaguars have not been well documented. We studied the foraging ecology of jaguars in an area with both livestock and native prey and documented kill rates, characteristics of prey killed, patterns of predation, and the influence of prey size on the duration at kill sites and the time interval between kills. Between October 2001 and April 2004 we monitored 10 jaguars equipped with global positioning system (GPS) collars. We collected 11,787 GPS locations and identified 1,105 clusters of ...


Using A Cost-Effectiveness Model To Determine The Applicability Of Ovocontrol G To Manage Nuisance Canada Geese, Joe Caudell, Stephanie A. Shwiff, Michael Slater 2010 USDA-APHIS-Wildlife Services

Using A Cost-Effectiveness Model To Determine The Applicability Of Ovocontrol G To Manage Nuisance Canada Geese, Joe Caudell, Stephanie A. Shwiff, Michael Slater

USDA National Wildlife Research Center - Staff Publications

OvoControl G is a relatively new product that reduces hatchability of Canada goose (Branta canadensis) eggs, and few data are available on its cost effectiveness. Variables such as presence of nontargets, alternative foods, and public support can affect cost efficacy. We present a model that uses these and other factors to estimate the cost of application of OvoControl G for managing nuisance Canada geese. We found that at low goose densities (<35 pairs of geese), fixed labor was a significant portion of costs. As goose densities increase, OvoControl G becomes more cost effective than other methods, such as egg oiling or addling. Managers can use this model to determine whether OvoControl G will provide a successful and cost-effective treatment for population control of Canada geese in specific management areas.


Integrity Of Mating Behaviors And Seasonal Reproduction In Coyotes (Canis Latrans) Following Treatment With Estradiol Benzoate, Debra A. Carlson, Eric M. Gese 2010 Utah State University, Logan, Department of Wildland Resources

Integrity Of Mating Behaviors And Seasonal Reproduction In Coyotes (Canis Latrans) Following Treatment With Estradiol Benzoate, Debra A. Carlson, Eric M. Gese

USDA National Wildlife Research Center - Staff Publications

Coyotes (Canis latrans) are seasonally monestrous and form perennial pair-bonds. Breeding is dominated by each pack’s alpha male and female, and both sexes share responsibility for territory defense and pup-rearing. They are also opportunistic predators on domestic livestock and pets. But while dominant adults have been implicated as primary killers, depredation is reduced when coyotes are without pups. Contraception, therefore, may represent a non-lethal solution for conflicts between coyotes and humans. Steroid hormones successfully control fertility in some species, but have been considered contraindicated in wildlife and canids in particular; specific concerns include possible induction of aberrant behavior, or ...


Feral Swine Behavior Relative To Aerial Gunning In Southern Texas, Tyler A. Campbell, David Long, Bruce Leland 2010 USDA-APHIS-Wildlife Services

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

USDA National Wildlife Research Center - Staff Publications

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


The Effect Of Enclosure Type On The Behavior And Heart Rate Of Captive Coyotes, Stacey P. Brummer, Eric M. Gese, John A. Shivik 2010 USDA-APHIS-Wildlife Services

The Effect Of Enclosure Type On The Behavior And Heart Rate Of Captive Coyotes, Stacey P. Brummer, Eric M. Gese, John A. Shivik

USDA National Wildlife Research Center - Staff Publications

The potential for captivity to elicit changes in animal behavior and physiology is well known. Recent research on captive populations has examined the effect of feeding protocols, enclosure types, and enrichment programs on indices of stress and displays of species-typical behaviors. We investigated the impact of enclosure type upon captive coyotes (Canis latrans) by examining differences in coyote behavior and heart rate, among 3.3m2 kennels (K), 65.5m2 small pens (S), and 1000m2 large pens (L). Time budgets and repertoire of species-specific behaviors were compared among each enclosure type and to a sample of wild (W ...


Review Of Issues Concerning The Use Of Reproductive Inhibitors, With Particular Emphasis On Resolving Human-Wildlife Conflicts In North America, Kathleen A. Fagerstone, Lowell A. Miller, Gary Killian, Christi A. Yoder 2010 USDA-APHIS-Wildlife Services

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

USDA National Wildlife Research Center - Staff Publications

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


The Economic Impacts To Commercial Farms From Invasive Monkeys In Puerto Rico, Richard M. Engeman, Jose´ E. Laborde, Bernice U. Constantin, Stephanie A. Shwiff, Parker Hall, Anthony Duffiney, Freddie Luciano 2010 USDA-APHIS-Wildlife Services

The Economic Impacts To Commercial Farms From Invasive Monkeys In Puerto Rico, Richard M. Engeman, Jose´ E. Laborde, Bernice U. Constantin, Stephanie A. Shwiff, Parker Hall, Anthony Duffiney, Freddie Luciano

USDA National Wildlife Research Center - Staff Publications

Beginning in the 1930s and continuing through the 1970s, rhesus macaques and patas monkeys were introduced to presumed secure locations, primarily coastal islets, in Puerto Rico. Escapes into the wild began almost immediately after introduction. Today the combined range of the two species covers approximately 600 km2 of southwestern Puerto Rico, where serious conflicts with agricultural interests have resulted. The Puerto Rico Department of Agriculture surveyed about 90% of commercial farmers in the range of the monkeys to begin quantifying damage by monkeys and the associated economic losses during the years 2002–2006. During that time, total economic losses ...


Evaluation Of Harassment Of Migrating Double-Crested Cormorants To Limit Depredation On Selected Sport Fisheries In Michigan, Brian S. Dorr, Ashley Moerke, Michael Bur, Chuck Bassett, Tony Aderman, Dan Traynor, Russell D. Singleton, Peter H. Butchko, Jimmy D. Taylor II 2010 USDA/APHIS/WS National Wildlife Research Center

Evaluation Of Harassment Of Migrating Double-Crested Cormorants To Limit Depredation On Selected Sport Fisheries In Michigan, Brian S. Dorr, Ashley Moerke, Michael Bur, Chuck Bassett, Tony Aderman, Dan Traynor, Russell D. Singleton, Peter H. Butchko, Jimmy D. Taylor Ii

USDA National Wildlife Research Center - Staff Publications

Diverse management techniques have been used to mitigate conflicts between humans and double-crested cormorants (Phalacrocorax auritus) including harassment methods supplemented by lethal take. In this study we evaluated impacts or programs to harass spring migrating cormorants on the walleye (Sander vitreus) fishery in Brevoort Lake and the yellow perch (Perca flavescens ) and walleye fisheries at Drummond Island. Cormorant foraging declined significantly (p < 0.05) at both locations subsequent to initiation of harassment programs. Overall harassment deteired 90% of cormorant foraging attempts while taking less than 6% lethally on average at each site. Yellow perch were a predominate prey item in number and biomass at both locations. Walleye made up a small proportion of the diet at both locations. However, both walleye and yellow perch abundance increased significantly (p<0.05) at Drummond Island. Walleye abundance at age 3 increased to record levels in 2008 following 3 years of cormorant management at Brevoort Lake. The estimated cormorant consumption of age 1 walleye in the absence of management at Brevoort Lake during 2005 would account for 55% of the record 2006 age 1 walleye population. These results support the hypothesis, that cormorant predation on spawning aggregations of sportfish was a significant mortality factor and cormorant management reduced sportfish mortality and increased abundance at both locations. Continuation of harassment programs and .fishery assessments will determine whether improvement of targeted sport fisheries through control of spring migrating cormorants is sustainable.


Jaguars, Livestock, And People In Brazil: Realities And Perceptions Behind The Conflict, Sandra C. Cavalcanti, Silvio Marchini, Alexandra Zimmermann, Eric M. Gese, David W. Macdonald 2010 USDA/APHIS/WS National Wildlife Research Center

Jaguars, Livestock, And People In Brazil: Realities And Perceptions Behind The Conflict, Sandra C. Cavalcanti, Silvio Marchini, Alexandra Zimmermann, Eric M. Gese, David W. Macdonald

USDA National Wildlife Research Center - Staff Publications

The jaguar (Panthera onca) is the largest predator in the Neotropics and is arguably the most charismatic species for .conservation in Central and South America. Regrettably, the jaguar is also the carnivore that is least compatible with humans in twenty-first century Brazil. This fundamental incompatibility is due to the jaguar's need for abundant, large prey, as well as extensive, undisturbed habitat. Humans (also large, top predators) have competed directly with jaguars for food (i.e. native and domestic ungulates) for as long as they have coexisted (Jorgenson and Redford 1993), and lately threaten them directly and indirectly through deforestation ...


An Evaluation Of Diazacon As A Potential Contraceptive In Non-Native Rose-Ringed Parakeets, Mark Lambert, Giovanna Massel, Christi Yoder, David Cowan 2010 Food and Environment Research Agency, United Kingdom

An Evaluation Of Diazacon As A Potential Contraceptive In Non-Native Rose-Ringed Parakeets, Mark Lambert, Giovanna Massel, Christi Yoder, David Cowan

USDA National Wildlife Research Center - Staff Publications

Rose-ringed parakeets (Psittacula krameri) have become widely established outside their native range through accidental or deliberate release. Potential economic impacts on agriculture, conservation concerns, and mixed public opinion regarding the species have highlighted the need to develop effective but humane management options. Fertility control might provide such a solution if a safe and environmentally benign contraceptive was available. The chemical 20,25-diazacholesterol dihydrochloride (diazacon) has previously been used to reduce reproductive output in avian species through reduction of blood cholesterol and cholesterol-dependent reproductive hormones. We orally dosed captive rose-ringed parakeets with a solution of either 9 mg/kg or 18 ...


Implications Of Stunting On Morphology Of Freshwater Fishes, Christopher J. Chizinski, Kevin L. Pope, G.R. Wilde, R.E. Strauss 2010 Texas Tech University

Implications Of Stunting On Morphology Of Freshwater Fishes, Christopher J. Chizinski, Kevin L. Pope, G.R. Wilde, R.E. Strauss

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

The purpose of this study was to assess morphological differences between stunted and non-stunted white perch Morone americana and green sunfish Lepomis cyanellus. Few female M. americana were captured; thus, morphological differences between adult males and juveniles were assessed for M. americana. Similarly, few immature (juvenile) L. cyanellus were captured for the stunted morphotype; thus, male and female morphological differences were assessed for L. cyanellus. Features of the head tended to be relatively larger in stunted fish of both species, whereas the mid-body tended to be relatively larger in non-stunted M. americana, but not in non-stunted L. cyanellus. Adult and ...


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