Digital Commons Network^™

Land Use And Climate Influences On Waterbirds In The Prairie Potholes, Greg M. Forcey, Wayne E. Thogmartin, George M. Linz, William J. Bleier, Patrick C. Mckann

United States Department of Agriculture Wildlife Services: Staff Publications

Aim We examined the influences of regional climate and land-use variables on mallard (Anas platyrhynchos), blue-winged teal (Anas discors), ruddy duck (Oxyura jamaicensis) and pied-billed grebe (Podilymbus podiceps) abundances to inform conservation planning in the Prairie Pothole Region of the United States.

Location The US portion of Bird Conservation Region 11 (US-BCR11, the Prairie Potholes), which encompasses six states within the United States: Montana, North Dakota, South Dakota, Nebraska, Minnesota and Iowa.

Methods We used data from the North American Breeding Bird Survey (NABBS), the National Land Cover Data Set, and the …

Health Effects Of Gnrh Immunocontraception Of Wild White-Tailed Deer In New Jersey, James P. Gionfriddo, Anthony J. Denicola, Lowell A. Miller, Kathleen A. Fagerstone

United States Department of Agriculture Wildlife Services: Staff Publications

We evaluated the health effects of GonaCon™ Immunocontraceptive Vaccine in individual white-tailed deer (Odocoileus virginianus) on a fully fenced corporate office campus in suburban New Jersey, USA. We captured and vaccinated adult females, fawns of both sexes, and yearling and adult males, and evaluated their health status through field and necropsy observations, assessment of blood chemistry, and histopathological examination of selected tissues. One 1.0-mL intramuscular injection of vaccine was delivered by hand to the hind limb of each GonaCon-treated deer. Control deer received sham injections (ad F) or no injections (yearling and ad M). Mean body-condition scores of …

Silvicultural Attempts To Induce Browse Resistance In Conifer Seedlings, B. A. Kimball, Fred Pfund, Mark Gourley, Doreen L. Griffin, John H. Russell

United States Department of Agriculture Wildlife Services: Staff Publications

A multiyear study was conducted to determine if soil amendment combined with topical application of elemental sulfur could be employed to reduce deer browse damage to four conifer species. Fertilizer and sulfur were applied to conifer seedlings at seven sites near Corvallis, OR. Growth and browse damage data were collected for all seedlings over a period of 17 months. Additionally, foliar concentrations of monoterpenes and simple carbohydrates were assessed in western redcedar (Thuja plicata) seedlings over a period of three years. Fertilization and sulfur treatments had a moderate impact on growth and no influence on browse damage or …

Evaluation Of Fences For Containing Feral Swine Under Simulated Depopulation Conditions, Michael J. Lavelle, Kurt C. Vercauteren, Hefley, Gregory E. Phillips, Scott Hygnstrom, David B. Long, Justin W. Fischer, Seth R. Swafford, Tyler A. Campbell

United States Department of Agriculture Wildlife Services: Staff Publications

Populations of feral swine (Sus scrofa) are estimated to include >2 million animals in the state of Texas, USA, alone. Feral swine damage to property, crops, and livestock exceeds $50 million annually. These figures do not include the increased risks and costs associated with the potential for feral swine to spread disease to domestic livestock. Thus, effective bio-security measures will be needed to quickly isolate affected feral swine populations during disease outbreaks. We evaluated enclosures built of 0.86-m-tall traditional hog panels for containing feral swine during 35 trials, each involving 6 recently caught animals exposed to increasing levels …

Acute Toxicity, Histopathology, And Coagulopathy In American Kestrels (Falco Sparverius) Following Administration Of The Rodenticide Diphacinone, Barnett A. Rattner, Katherine E. Horak, Sarah E. Warner, Daniel D. Day, Carol U. Meteyer, Steven F. Volker, John D. Eisemann, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

The acute oral toxicity of the anticoagulant rodenticide diphacinone was found to be over 20 times greater in American kestrels (Falco sparverius; median lethal dose 96.8 mg/kg body weight) compared with Northern bobwhite (Colinus virginianus) and mallards (Anas platyrhynchos). Modest evidence of internal bleeding was observed at necropsy, although histological examination of heart, liver, kidney, lung, intestine, and skeletal muscle revealed hemorrhage over a wide range of doses (35.1–675 mg/kg). Residue analysis suggests that the half-life of diphacinone in the liver of kestrels that survived was relatively short, with the majority of the dose …

Reassortant H9n2 Influenza Viruses Containing H5n1- Like Pb1 Genes Isolated From Black-Billed Magpies In Southern China, Guoying Dong, Cong Xu, Chengmin Wang, Bin Wu, Jing Luo, Hong Zhang, Dale L. Nolte, Thomas Jude Deliberto, Mingxing Duan, Guangju Ji, Hongxuan He

United States Department of Agriculture Wildlife Services: Staff Publications

H9N2 influenza A viruses have become endemic in different types of terrestrial poultry and wild birds in Asia, and are occasionally transmitted to humans and pigs. To evaluate the role of black-billed magpies (Pica pica) in the evolution of influenza A virus, we conducted two epidemic surveys on avian influenza viruses in wild black-billed magpies in Guangxi, China in 2005 and characterized three isolated black-billed magpie H9N2 viruses (BbM viruses). Phylogenetic analysis indicated that three BbM viruses were almost identical with 99.7 to 100% nucleotide homology in their whole genomes, and were reassortants containing BJ94-like (Ck/BJ/1/94) HA, NA, …

Long-Term Fertility Control In Female Cats With Gonacon™, A Gnrh Immunocontraceptive, Julie K. Levy, John A. Friary, Lowell A. Miller, Sylvia J. Tucker, Kathleen A. Fagerstone

United States Department of Agriculture Wildlife Services: Staff Publications

The uncontrolled reproduction of free-roaming feral cats contributes to overpopulation and associated concerns regarding their welfare and impact on public health and the environment. Nonsurgical fertility control that could be administered to feral cats in the field would be a powerful tool for cat population control. The objective was to test the efficacy and duration of activity of a single-dose GnRH immunocontraceptive vaccine (GonaCon™) on the fertility of adult female laboratory cats. Vaccinated cats (n = 15) received a single injection of vaccine containing a GnRH-KLH conjugate (200 μg) emulsified in a mycobacterial and oil adjuvant on study Day …

Modeling Parental Provisioning By Red-Winged Blackbirds In North Dakota, George M. Linz, Richard S. Sawin, Mark W. Lutman, William J. Bleier

United States Department of Agriculture Wildlife Services: Staff Publications

Male red-winged blackbirds (Agelaius phoeniceus) exhibit a difference in nest provisioning rates along an east-west gradient, in North America. North Dakota is located in the center of North America and harbors a large population of breeding red-winged blackbirds (RWBL). This location provided an opportunity to compare provisioning rates in the central U.S. with those reported for the eastern and western populations. We placed video cameras at RWBL nests to record male and female feeding trips. Thirty-four nests were located on territories with original males and 30 were on territories where a replacement (floater) male had taken over a …

Life History And Ecology Of Coyotes In The Mid-Atlantic States: A Summary Of The Scientifi C Literature, Lauren L. Mastro

United States Department of Agriculture Wildlife Services: Staff Publications

Relatively little information has been published on Coyotes in the eastern United States, particularly in the mid-Atlantic region, the last area of the contiguous US to be colonized by Coyotes. Increases in eastern Coyote distribution and abundance have been documented, and concerns about their impact on wildlife and livestock are growing. Information from published and unpublished manuscripts, theses, dissertations, and state wildlife agency records in the mid-Atlantic region were examined and synthesized. This review provides a comprehensive summary of Coyote ecology in the mid-Atlantic for natural resource managers and researchers.

Excluding Nontarget Species From Brown Tree Snake, Boiga Irregularis (Reptilia: Colubridae), Bait Stations: Experimental Tests Of Station Design And Placement, Tom Mathies, Russell Scarpino, Brenna A. Levine, Craig S. Clark, Julie A. Savidge

United States Department of Agriculture Wildlife Services: Staff Publications

Bait stations with toxic baits are an emerging technology for eradication of the invasive brown tree snake (Boiga irregularis) on Guam, yet potential interferences by nontarget species are largely unknown. We tested the efficacies of three bait station designs together with three commonly used station support structures to exclude nonnative rats (roof rat, Rattus rattus; Norway rat, Rattus norvegicus; Polynesian rat, Rattus exulans) and native coconut crabs (Birgus latro). When directly presented, all species readily consumed the dead neonatal mouse baits (nontoxic) including those replicating decomposing baits in the field. When bait stations …

Phylogenetic And Population Genetic Assessment Of Rafinesque’S Big-Eared Bat (Corynorhinus Rafinesquii), Antoinette J. Piaggio, David A. Saugey, D. Blake Sasse

United States Department of Agriculture Wildlife Services: Staff Publications

Rafinesque’s big-eared bat (Corynorhinus rafinesquii) is distributed across the Southeastern United States. Due to habitat loss and low population numbers, this species is a Federal species of concern and protected by every State within its range. Effective management of any species of concern is dependent on an unambiguous understanding of taxonomic relationships. However, for this species, there are discordant inferences about subspecific designations from previous studies. Further, there have been no assessments of population genetic status for this species. Such assessments could provide information on genetic diversity and population connectivity and increase our understanding of the need for …

Effects Of Seasons And Hunting On Space Use By Female White-Tailed Deer In A Developed Landscape In Southeastern Nebraska, Scott E. Hygnstrom, Kurt C. Vercauteren, Scott R. Groepper, Gary W. Garabrandt, Joseph A. Gubanyi

United States Department of Agriculture Wildlife Services: Staff Publications

White-tailed deer (Odocoileus virginianus) were extirpated from a 1,800-ha natural area along the Missouri River near Omaha, Nebraska, USA shortly after settlement in the mid-1800s, but they recolonized the area in the early 1960s. In absence of hunting and predators, the population of deer became overabundant in the 1980s and 1990s. Deer impacted plant communities at Fontenelle Forest (FF) and Gifford Point (GP) and a 200–300% increase in deer–vehicle collisions was observed in the area. We radiocollared female white-tailed deer in this region during February 1995–March 1996 to determine the effects of phenological seasons and archery and muzzleloader …

Population Estimation And Monitoring Of An Endangered Lagomorph, Jason A. Schmidt, Robert A. Mccleery, Paige M. Schmidt, Nova. J. Silvy, Roel Lopez

United States Department of Agriculture Wildlife Services: Staff Publications

We conducted the most intensive estimate of the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) metapopulation to date using pellet surveys and capture–recapture methodology. We live trapped 83 rabbits, evaluated 5 closed population models, and selected the model that best represented the data. We considered the variation in behavioral response model the best model and correlated (r² = 0.913) its patch population estimates to patch pellet densities. From the prediction equation, we generated a range-wide metapopulation estimate of 317 rabbits, a western clade population of 257 rabbits, an eastern clade population of 25 rabbits, and translocated …

Electric Shock Strips As Bird Deterrents: Does Experience Count?, Thomas W. Seamans, Bradley F. Blackwelll

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding how birds detect and react to deterrent methods which are employed to protect structures is important both for the effective control of property damage, and to ensure that human health and safety are not compromised. One such device is a shock strip that causes slight pain to birds when they use a perch. Our aims were to determine: (1) the efficacy of a shock strip to flocks of Brown-headed Cowbirds (Molothrus ater), and Rock Pigeons (Columba livia); (2) the length of time to extinction of effect; (3) whether members of a flock show a behavioural …

Immunocontraception In Eastern Gray Squirrels (Sciurus Carolinensis): Morphologic Changes In Reproductive Organs, Murali Pai, R. Bruner, Donald H. Schlafer, Greg K. Yarrow, C. A. Yoder, Lowell A. Miller

United States Department of Agriculture Wildlife Services: Staff Publications

Eastern gray squirrels (EGS) (Sciurus carolinensis) damage trees through bark stripping or gnawing due to territorial marking or agonistic gnawing behavior in concert with higher densities. This study was conducted to determine the effects of a contraceptive vaccine on EGS and its reproductive organ histology. Free ranging urban EGS were vaccinated with the immunocontraceptive GonaCon™. All EGS were ≥6 mo. of age as determined by a combination of pelage characteristics and body weights. The vaccine was administered by injection at a dosage rate of 0.4 ml containing 400 μg of GnRH-mollusk protein conjugate i.m. in the thigh to …

A Retrospective Economic Analysis Of The Ontario Red Fox Oral Rabies Vaccination Programme, S. A. Shwiff, C. P. Nunan, Katy N. Kirkpatrick, S. S. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

Ontario initiated a red fox (Vulpes vulpes) oral rabies vaccination (ORV) programme in 1989. This study utilized a benefit-cost analysis to determine if this ORV programme was economically worthwhile. Between 1979 and 1989, prior to ORV baiting, the average annual human post-exposure treatments, positive red fox rabies diagnostic tests and indemnity payments for livestock lost to rabies were 2248, 1861 and $246 809, respectively. After baiting, from 1990 to 2000, a 35%, 66% and 41% decrease in post-exposure treatments, animal rabies tests and indemnity payments was observed, respectively. These reductions were viewed as benefits of the ORV programme, …

Identifying And Managing For Wildlife Damage During Stand Initiation, Jimmy D. Taylor Ii

United States Department of Agriculture Wildlife Services: Staff Publications

Trees in the Pacific Northwest (PNW) are susceptible to wildlife damage throughout their life cycles, and many industrial and nonindustrial forest landowners spend a good deal of money attempting to prevent or lessen this damage. Several species of animals affect forest regeneration and their damage can generally be broken into categories based on when damage occurs. During stand initiation, damage is seen with seeds, seedlings, and saplings. While some animals may cause damage only at one particular time, others damage trees at various intervals and in different ways. Methods of lethal and non-lethal control to reduce wildlife damage have been …

Evaluation Of Sonic Dissuader® To Reduce Damage By Pileated Woodpeckers, Shelagh K. Tupper, John L. Cummings, William F. Andelt, Scott Werner, Richard Harness

United States Department of Agriculture Wildlife Services: Staff Publications

Woodpecker damage to utility poles results in significant monetary losses to utility companies worldwide. Most techniques for repelling woodpeckers from utility poles are costly, difficult to install, effective for a limited time, or ineffective. We evaluated the Sonic Dissuader for detecting and deterring pileated woodpecker (Dryocopus pileatus) damage to wooden utility poles in controlled flight pens. The Sonic Dissuader emits pileated woodpecker and avian predator calls contingent upon pecking by woodpeckers. Ratios of departure were lower and woodpeckers spent more time after a pecking event on the pole with the Sonic Dissuader compared to the control pole (paired …

Regulated Commercial Harvest To Manage Overabundant White-Tailed Deer: An Idea To Consider?, Kurt C. Vercauteren, Charles W. Anderson, Timothy R. Van Deelen, David Drake, W. David Walter, Stephen Vantassel, Scott E. Hygnstrom

United States Department of Agriculture Wildlife Services: Staff Publications

Declines in hunter recruitment coupled with dramatic growth in numbers of white-tailed deer (Odocoileus virginianus) have challenged our ability to manage deer populations through regulated hunting. We review the efficacy of current regulated hunting methods and explain how they are unable to reduce deer numbers sufficiently in some environments. Regulated commercial harvest would provide an additional tool to help state wildlife agencies manage overabundant populations of white-tailed deer. We outline potential means to govern regulated commercial deer harvest and explain how it is compatible with the North American Model of Wildlife Conservation. We identified several benefits, including reduced …

What Is The Proper Method To Delineate Home Range Of An Animal Using Today’S Advanced Gps Telemetry Systems: The Initial Step, W. David Walter, Justin W. Fischer, Sharon Baruch-Mordo, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

The formal concept of an animal’s home range, or derivations thereof, has been around for over half a century (Burt 1943). Within this time frame there have been countless published studies reporting home range estimators with no consensus for any single technique (Withey et al., 2001; Laver & Kelly 2008). Recent advances in global positioning system (GPS) technology for monitoring home range and movements of wildlife have resulted in locations that are numerous, more precise than very high frequency (VHF) systems, and often are auto correlated in space and time. Along with these advances, researchers are challenged with understanding the …

Anthraquinone Repellent To Reduce Take Of Non-Target Birds From Zinc Phosphide Rodenticide Applications, Scott J. Werner, Shelagh K. Tupper, Susan E. Pettit, James C. Carlson, George M. Linz

United States Department of Agriculture Wildlife Services: Staff Publications

We evaluated anthraquinone as an avian repellent to reduce take of non-target birds from zinc phosphide rodenticide applications. We observed zero mortalities and no overt signs of zinc phosphide toxicosis among 20 Canada geese (Branta canadensis), 24 horned larks (Eremophila alpestris), and 47 ring-necked pheasants (Phasianus colchicus) offered baits treated with 1% or 2% anthraquinone and 2% zinc phosphide (target concentrations; wt/wt) during laboratory performance experiments. Thus, anthraquinone successfully prevented consumption of 2% zinc phosphide baits among non-target birds in captivity. We observed 10% mortality among black-tailed prairie dogs (i.e., target rodent; Cynomys ludovicianus …

Coyote Capture Vulnerability Relative To Space Use And Trap Density, Ryan R. Wilson, Julie K. Young, John Shivik

United States Department of Agriculture Wildlife Services: Staff Publications

Coyotes (Canis latrans) are reported to be less vulnerable to capture in familiar areas of territories, however, most studies do not control for trap density across the territory. We determined if accounting for trap density provided a better explanation of observed capture rates. Based on a sample of 24 captured coyotes (6 inside core areas and 18 on peripheries of occupied areas) the best fitting model describing capture location only accounted for trap density and not relative time spent in each region. Our results suggest that coyote capture rates are a function of trap density in an area …

Eradication Of Invasive Rodents On Islands Of The United States, Gary W. Witmer, J. Pierce, William C. Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

Many invasive rodents have become established in the United States and its territories. The species include several species of Rattus, house mice (Mus musculus), Gambian giant pouched rats (Cricetomys gambianus), ground squirrels (Spermophilus parryii), nutria (Myocastor coypus) and marmots (Marmota caligata). These rodents have caused serious impacts to native flora and fauna, agriculture, and other resources. Since the early 1990s, agencies have been eradicating rodents from various islands, primarily for conservation purposes. Of about 40 eradication attempts, 22 (55%) appear to have succeeded. For several islands, however, it is …

Attempting To Eradicate Invasive Gambian Giant Pouched Rats (Cricetomys Gambianus) In The United States: Lessons Learned, Gary W. Witmer, P. Hall

United States Department of Agriculture Wildlife Services: Staff Publications

Gambian giant pouched rats (Cricetomys gambianus) are native to Africa, but they are popular pets in the United States. They caused a monkeypox outbreak in the Midwestern United States in 2003 in which 72 people were infected. A free-ranging population became established on the 400 ha Grassy Key in the Florida Keys, apparently after a release by a pet breeder. This rodent species is known to cause extensive crop damage in Africa and if it reaches the mainland US, many impacts, especially to the agriculture industry of Florida, can be expected. An apparently successful inter-agency eradication effort has …

Feeding Of Grey Squirrels (Sciurus Carolinensis) With The Contraceptive Agent Diazacontm: Effect On Cholesterol, Hematology, And Blood Chemistry, C. A. A. Yoder, Brenda A. Mayle, Carol A. Furcolow, David N. Cowan, Kathleen A. Fagerstone

United States Department of Agriculture Wildlife Services: Staff Publications

Grey squirrels (Sciurus carolinensis) are an invasive species in Britain and Italy. They have replaced native red squirrels (Sciurus vulgaris) throughout most of Britain, and cause damage to trees. Currently, lethal control is used to manage grey squirrel populations in Britain, but nonlethal methods might be more acceptable to the public. One such method is contraception with 20,25-diazacholesterol dihydrochloride (DiazaCon^TM). DiazaCon^TM inhibits the conversion of desmosterol to cholesterol, resulting in increasing desmosterol concentrations and decreasing cholesterol concentrations. Because cholesterol is needed for the synthesis of steroid reproductive hormones, such as progesterone and testosterone, …

Diseases And Parasites [Of White-Tailed Deer], Tyler A. Campbell, K. C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife biologists have long pursued understanding the ecology of diseases and parasites impacting white-tailed deer (e.g., see Whitlock, 1939), an important field of study because they can detrimentally affect deer populations, other wildlife, livestock, and humans (Davidson et aI., 1981). Diseases and parasites of white-tailed deer, perhaps more than any other North American large mammal species, have received much attention in the literature and complete treatises have been devoted to the subject (e.g., see Davidson et aI., 1981). In the last 20 years it has become necessary for wildlife biologists to incorporate disease concerns into the management of white-tailed deer …

Characteristics Of Road-Kill Locations Of San Clemente Island Foxes, Nathan P. Snow, William F. Andelt, Nicholas P. Gould

United States Department of Agriculture Wildlife Services: Staff Publications

Mortalities from collisions with vehicles have created concern for the welfare of the San Clemente Island fox (Urocyon littoralis clementae); 1 of only 6 genetically distinct subspecies of island fox. To find possible solutions for minimizing these mortalities, we compared 9 characteristics of roads and roadsides at kill-sites and control-sites to ascertain whether certain features were associated with risk of collisions. We found that kill-sites were positively associated with the volume of traffic, and negatively associated with the distance of motorists’ visibility, which had not been previously identified for island foxes. Additionally, visual obstructions along roadsides (i.e., steep …

A Field Evaluation Of A Trap For Invasive American Bullfrogs, Nathan P. Snow, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Native to the eastern United States, American bullfrogs (Rana catesbeiana [Lithobates catesbeianus]) have been introduced in many countries throughout the world. There have been relatively few effective and efficient control methods developed to manage bullfrogs. Particularly in the Hawaiian Islands, Pacific coast of North America, and Japan, finding effective methods for controlling invasive bullfrogs is needed with special emphasis on low impacts for sensitive native species. We conducted a field study to examine the efficacy of a newly designed live trap for capturing invasive bullfrogs. We found that our trap was successful at capturing bullfrogs because we …

Activity Patterns Of Wild Boars (Sus Scrofa) In Southern Texas, Tyler A. Campbell, David B. Long

United States Department of Agriculture Wildlife Services: Staff Publications

ABSTRACT—Wild boars (Sus scrofa) are increasing in abundance and geographic distribution throughout North America. Our objectives were to determine daily and hourly activity patterns. We placed global-positioning-system collars on 25 wild boars from two sites in southern Texas. Wild boars at both sites displayed highly nocturnal activity patterns, and during the dormant and early growing season, activity increased with rising temperatures.

RESUMEN—Los jabalı´s (Sus scrofa) esta´n incrementando su abundancia y distribucio´n geogra´fica en toda Norteame´rica. Nuestros objetivos fueron determinar los patrones de actividad por dı´a y por hora. Colocamos collares con sistemas de posicionamiento …

Ganadería Y Fauna Silvestre Del Noreste De México Y Sur De Texas E Implicaciones De La Garrapata Boophilus: Opción De Los Ganaderos, Eduardo A. González-V, David G. Hewitt, J. Alfonso Ortega-Santos, Randy W. Deyoung, Tyler A. Campbell, Fred C. Bryant

United States Department of Agriculture Wildlife Services: Staff Publications

La ganaderia de bovinos de came en sistemas de pastoreo extensivo es una de las actividades económicas mas importantes en el sur de Texas (Turner y Ducoing 1998) y noreste de México (Rodriguez et al. 1998; González y Hanselka 2002). Sin embargo, debido a la abundancia de fauna silvestre, en especial del venado cola blanca (Odocoileus virginianus), la caceria y actividades recreativas al aire libre, se han convertido en años recientes en empresas importantes (Hanselka et al. 1991, Fulbright y Ortega 2006).

Durante los últimos 50 años ha cambiado la visión de los dueños de la tierra de …