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Effects Of Crop Type And Harvest On Nest Survival And Productivity Of Dickcissels In Semi-Natural Grasslands, Tara J. Conkling, Jerrold L. Belant, Travis L. Devault, James A. Martin

United States Department of Agriculture Wildlife Services: Staff Publications

Recent focus on climate change and global energy production has increased interest in developing biofuels including perennial native grasses (e.g. switchgrass [Panicum virgatum]) as viable energy commodities while simultaneously maintaining ecosystem function and biodiversity. However, there is limited research examining the effects of biofuel-focused grasslands on grassland bird reproductive success and conservation. In 2011–2013 we studied the effects of vegetation composition and harvest regimens of switchgrass monocultures and native warm-season grass (NWSG) mixtures on nest success, nest density, and productivity for dickcissels (Spiza americana) in Clay Co. MS, USA. There was no effect of vegetation metrics, …

Functional Visual Sensitivity To Ultraviolet Wavelengths In The Pileated Woodpecker (Dryocopus Pileatus), And Its Influence On Foraging Substrate Selection, Sean T. O'Daniels, Dylan C. Kesler, Jeanne D. Mihail, Elisabeth B. Webb, Scott J. Werner

United States Department of Agriculture Wildlife Services: Staff Publications

Most diurnal birds are presumed visually sensitive to near ultraviolet (UV)wavelengths, however, controlled behavioral studies investigating UV sensitivity remain few. Although woodpeckers are important as primary cavity excavators and nuisance animals, published work on their visual systems is limited. We developed a novel foraging-based behavioral assay designed to test UV sensitivity in the Pileated Woodpecker (Dryocopus pileatus). We acclimated 21 wild-caught woodpeckers to foraging for frozen mealworms within 1.2 m sections of peeled cedar (Thuja spp.) poles.We then tested the functional significance of UV cues by placing frozen mealworms behind UV-reflective covers, UV-absorptive covers, or decayed red …

Movement Of Hypophthalmichthys Dna In The Illinois River Watershed By The Double-Crested Cormorant (Phalacrocorax Auritus), Michael P. Guilfoyle, Heather L. Farrington, Richard F. Lance, Katie C. Hanson-Dorr, Brian S. Dorr, Richard A. Fischer

United States Department of Agriculture Wildlife Services: Staff Publications

Paired throat and cloacal swabs, along with feather samples, from nesting Double-crested Cormorants (Phalacrocorax auritus) at two sites in Illinois, USA, were tested for presence of invasive bigheaded carp (Hypophthalmichthys spp.) DNA. We also used DNA from the feather calamus to determine cormorant sex. Throat and cloacal swabs from cormorants at both locations tested positive for DNA from silver carp (H. molitrix), but none tested positive for bighead carp (H. nobilis). Hypophthalmichthys DNA was not detected on feathers. There were no significant differences among positive Hypophthalmichthys DNA detection frequencies between cormorant sexes. To …

Uncovering Behavioural States From Animal Activity And Site Fidelity Patterns, Peter J. Mahoney, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

1. Space use by animals has important implications for individual fitness. However, resource requirements often vary throughout the course of a lifetime and are a reflection of the demands associated with daily tasks or specific life-history phases, from food acquisition to reproduction, and emphasize the need to classify resource selection relative to specific behavioural states. Site fidelity is often indicative of behaviours important for individual maintenance (e.g. foraging), species’ life history (e.g. seasonal site selection), social communication (e.g. scent-marking) and species interactions (e.g. predation, competition). Thus, resolving site fidelity patterns associated with key behaviours is essential to accurately quantify behavioural-dependent …

Temporal Development Of Gut Microbiota In Triclocarban Exposed Pregnant And Neonatal Rats, Rebekah C. Kennedy, Russell R. Fling, Michael S. Robeson, Arnold M. Saxton, Robert L. Donnell, John L. Darcy, David A. Bemis, Jiang Liu, Ling Zhao, Jiangang Chen

United States Department of Agriculture Wildlife Services: Staff Publications

Alteration of gut microbial colonization process may influence susceptibility of the newborn/infant to infectious and chronic disease. Infectious disease risk leads to widespread use of non-prescription antimicrobials in household products such as Triclocarban (TCC), an antimicrobial compound in personal care products. TCC concentrates in and is transferred through the milk to suckling offspring. TCC exposure during gestation and lactation significantly reduced phylogenetic diversity (PD) among exposed dams and neonates. Among dams using weighted UniFrac distances, TCC induced significant dysbiosis of gut microbiota by gestational day (GD) 18, a trend that continued after delivery. Similarly, an overall restructuring of gut microbiota …

Diazacon Reduces Black-Tailed Prairie Dog Reproduction In Colorado, Christi A. Yoder, Richard E. Mauldin, James P. Gionfriddo, Kenneth A. Crane, David A. Goldade, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Context. Black-tailed prairie dogs (Cynomus ludovicianus) often come into conflict with humans in urban natural areas adjacent to private property by destroying plants and denuding the landscape. There is a diversity of attitudes related to urban prairie dog management in Colorado and interest in non-lethal methods is increasing. Therefore, the development of non-lethal methods that allow the existence of prairie dogs and mitigate damage related to population density is needed.

Aims. The efficacy of DiazaCon (20,25-diazacholesterol dihydrochloride, a cholesterol analogue) as an oral contraceptive bait for reducing reproduction in black-tailed prairie dogs was tested. Persistence of DiazaCon in …

Development Of Methods For Avian Oil Toxicity Studies Using The Double Crested Cormorant (Phalacrocorax Auritus), Fred L. Cunningham, Karen Dean, Katie C. Hanson-Dorr, Kendal Harr, Kate Healy, Katherine E. Horak, Jane Link, Susan A. Shriner, Steve J. Bursian, Brian S, Dorr

United States Department of Agriculture Wildlife Services: Staff Publications

Oral and external dosing methods replicating field exposure were developed using the double crested cormorant (DCCO) to test the toxicity of artificially weathered Deepwater Horizon Mississippi Canyon 252 oil. The majority of previous oil dosing studies conducted on wild-caught birds used gavage methods to dose birds with oil and determine toxicity. However, rapid gut transit time of gavaged oil likely reduces oil absorption. In the present studies, dosing relied on injection of oil into live feeder fish for oral dosing of these piscivorous birds, or applying oil to body contour feathers resulting in transdermal oil exposure and oral exposure through …

Dermal Exposure To Weathered Mc252 Crude Oil Results In Echocardiographically Identifiable Systolic Myocardial Dysfunction In Double-Crested Cormorants (Phalacrocorax Auritus), K. E. Harr, M. Rishniw, T. L. Rupp, D. Cacela, K. M. Dean, B. S. Dorr, K. C. Hanson-Dorr, K. Healy, K. E. Horak, J. E. Link, D. Reavill, S. J. Bursian, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

During the Deepwater Horizon Natural Resource Damage Assessment, gross morphologic cardiac abnormalities, including softer, more distensible musculature, were noted upon gross necropsy in hearts from laughing gulls and double-crested cormorants exposed to weathered MC252 crude oil. A species specific, echocardiographic technique was developed for antemortem evaluation of function that was used to evaluate and better characterize cardiac dysfunction. Control (n=12) and treated (n=13) cormorant groups of similar sex-ratio and ages were dermally treated with approximately 13 ml of water or weathered MC252 crude oil, respectively, every 3 days for 6 dosages. This resulted in a low to moderate external exposure. …

Reprint Of: Cyp1a Protein Expression And Catalytic Activity In Double-Crested Cormorants Experimentally Exposed To Deepwater Horizon Mississippi Canyon 252 Oil, Courtney R. Alexander, Michael J. Hooper, Dave Cacela, Kim D. Smelker, Caleshia S. Calvin, Karen M. Dean, Steve J. Bursian, Fred L. Cunningham, Katie C. Hanson-Dorr, Katherine E. Horak, John P. Isanhart, Jane Link, Susan A. Shriner, Céline A.J. Godard-Codding

United States Department of Agriculture Wildlife Services: Staff Publications

Double-crested cormorants (Phalacrocorax auritus, DCCO) were orally exposed to Deepwater Horizon Mississippi Canyon 252 (DWH) oil to investigate oil-induced toxicological impacts. Livers were collected for multiple analyses including cytochrome P4501A (CYP1A) enzymatic activity and protein expression. CYP1A enzymatic activity was measured by alkoxyresorufin O-dealkylase (AROD) assays. Activities specific to the O-dealkylation of four resorufin ethers are reported: benzyloxyresorufin O-debenzylase (BROD), ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), and pentoxyresorufin O-depentylase (PROD). CYP1A protein expression was measured by western blot analysis with a CYP1A1 mouse monoclonal antibody. In study 1, hepatic BROD, EROD, and PROD activities were significantly induced in …

A Method For The Improved Detection Of Aerosolized Influenza Viruses And The Male-Specific (F+) Rna Coliphage Ms2, J. C. Chandler, J. W. Schaeffer, M. Davidson, S. L. Magzamen, A. Pérez-Méndez, S. J. Reynolds, L. D. Goodridge, J. Volckens, A. B. Franklin, S. A. Shriner, B. Bisha

United States Department of Agriculture Wildlife Services: Staff Publications

The detection of aerosolized viruses can serve as an important surveillance and control tool in agriculture, human health, and environmental settings. Here, we adapted an anion exchange resin-based method, initially developed to concentrate negatively charged viruses from water, to liquid impingement-based bioaerosol sampling. In this method, aerosolized viruses are collected in a 20 ml liquid sample contained within widely used impingers, BioSamplers (SKC Inc., Eighty Four, PA), and further concentrated via adsorption to an anion exchange resin that is suspended within this liquid. Viral nucleic acids are then extracted from the resin to facilitate molecular analyses through a reduction in …

Weathered Mc252 Crude Oil-Induced Anemia And Abnormal Erythroid Morphology In Double-Crested Cormorants (Phalacrocorax Auritus) With Light Microscopic And Ultrastructural Description Of Heinz Bodies, K. E. Harr, Fred L. Cunningham, Chris A. Pritsos, Karen L. Pritsos, Thivanka Muthumalage, Brian S. Dorr, Katherine E. Horak, Katie C. Hanson-Dorr, Karen M. Dean, Dave Cacela, Andrew K. Mcfadden, Jane E. Link, Katherine A. Healy, Pete Tuttle, Steven J. Bursian

United States Department of Agriculture Wildlife Services: Staff Publications

Injury assessment of birds following the Deepwater Horizon (DWH) oil spill in 2010 was part of the Natural Resource Damage Assessment. One reported effect was hemolytic anemia with the presence of Heinz bodies (HB) in birds, however, the role of route and magnitude of exposure to oil is unknown. The purpose of the present study was to determine if double-crested cormorants (Phalacocorax auritis; DCCO) exposed orally and dermally to artificially weathered crude oil would develop hemolytic anemia including HB and reticulocytosis. In the oral experiment, sub-adult, mixed-sex DCCOs were fed control (n = 8) or oil–injected fish with …

Organ Weights And Histopathology Of Double-Crested Cormorants (Phalacrocorax Auritus) Dosed Orally Or Dermally With Artificially Weathered Mississippi Canyon 252 Crude Oil, K. E. Harr, Drury R. Reavill, Steven J. Bursian, Dave Cacela, Fred L. Cunningham, Karen M. Dean, Brian S. Dorr, Katie C. Hanson-Dorr, Kate Healy, Katherine E. Horak, Jane E. Link, Susan A. Shriner, Robert E. Schmidt

United States Department of Agriculture Wildlife Services: Staff Publications

A series of toxicity tests were conducted to assess the effects of low to moderate exposure to artificially weathered Deepwater Horizon Mississippi Canyon 252 crude oil on representative avian species as part of the Natural Resource Damage Assessment. The present report summarizes effects of oral exposure (n=26) of double crested cormorants (DCCO; Phalacrocorax auritus) to 5 or 10 ml oil kg⁻¹ day⁻¹ for up to 21 days or dermal application (n=25) of 13 ml oil to breast and back feathers every three days totaling 6 applications in 21 days on organ weights and histopathology. Absolute and relative …

Ecological Potential For Rabies Virus Transmission Via Scavenging Of Dead Bats By Mesocarnivores, Tad C. Theimer, Annie C. Dyer, Brian W. Keeley, Amy T. Gilbert, David L. Bergman

United States Department of Agriculture Wildlife Services: Staff Publications

Multiple species of bats are reservoirs of rabies virus in the Americas and are occasionally the source of spillover infections into mesocarnivore species. Although rabies transmission generally is assumed to occur via bite, laboratory studies have demonstrated the potential for rabies transmission via ingestion of rabid animals. We investigated the ecological potential for this mode of transmission by assessing mesocarnivore scavenging behavior of dead bats in suburban habitats of Flagstaff, Arizona, US. In autumn 2013, summer 2014, and autumn 2015, we placed 104 rabies-negative bat carcasses either near buildings, in wildland areas, or in residential yards and then monitored them …

Towards Canine Rabies Elimination In Cebu, Philippines: Assessment Of Health Economic Data, L. M. Miranda, M. E. Miranda, B. Hatch, R. Deray, S. A. Shwiff, M. C. Roces, C. E. Rupprecht

United States Department of Agriculture Wildlife Services: Staff Publications

Rabies is endemic in the Philippines. In 2010, with support from the Bill and Melinda Gates Foundation, a canine rabies elimination project was initiated in the Philippine Archipelago of Visayan. We conducted an analysis of dog vaccination and human PEP costs for dog bite patients in a highly urbanized area and a low-income rural municipality in Cebu Province, Philippines, from 2010 to 2012. Our findings indicated that eliminating rabies in dogs through mass vaccination is more cost-effective than treating rabies exposures in humans. The average costs (in USD) per human life saved through PEP were $1620.28 in Cebu City and …

Diversity And Phylogenetic Relationships Among Bartonella Strains From Thai Bats, Clifton D. Mckee, Michael Y. Kosoy, Ying Bai, Lynn M. Osikowicz, Richard Franka, Amy T. Gilbert, Sumalee Boonmar, Charles E. Rupprecht, Leonard Peruski

United States Department of Agriculture Wildlife Services: Staff Publications

Bartonellae are phylogenetically diverse, intracellular bacteria commonly found in mammals. Previous studies have demonstrated that bats have a high prevalence and diversity of Bartonella infections globally. Isolates (n = 42) were obtained from five bat species in four provinces of Thailand and analyzed using sequences of the citrate synthase gene (gltA). Sequences clustered into seven distinct genogroups; four of these genogroups displayed similarity with Bartonella spp. sequences from other bats in Southeast Asia, Africa, and Eastern Europe. Thirty of the isolates representing these seven genogroups were further characterized by sequencing four additional loci (ftsZ, nuoG, rpoB, …

An Assessment Of Radiative Heating As A Thermal Treatment For Invasive Snakes In Cargo, Fred Kraus, Randal S. Stahl, William Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

The brown tree snake (Boiga irregularis) is invasive in Guam and presents a continuous threat of accidental export to new islands in outbound cargo. Current attempts to avoid that scenario rely primarily on canine teams to inspect outbound cargo and vehicles. In prior work, we showed that thermal fumigation could effectively elicit snake exit of cargo under conditions when free flow of air streams is feasible, but this method cannot work with tightly packed cargo. Here we show radiative heating can effectively induce snake exit from cargo refuges at temperatures of 44–48 C; however, we find passive solar …

Fine-Scale Assessment Of Home Ranges And Activity Patterns For Resident Black Vultures (Coragyps Atratus) And Turkey Vultures (Cathartes Aura), Amanda E. Holland, Michael E. Byrne, A. Lawrence Bryan, Travis L. Devault, Olin E. Rhodes Jr., James C. Beasley

United States Department of Agriculture Wildlife Services: Staff Publications

Knowledge of black vulture (Coragyps atratus) and turkey vulture (Cathartes aura) spatial ecology is surprisingly limited despite their vital ecological roles. Fine-scale assessments of space use patterns and resource selection are particularly lacking, although development of tracking technologies has allowed data collection at finer temporal and spatial resolution. Objectives of this study were to conduct the first assessment of monthly home range and core area sizes of resident black and turkey vultures with consideration to sex, as well as elucidate differences in monthly, seasonal, and annual activity patterns based on fine-scale movement data analyses. We collected …

Use Of Fecal Volatile Organic Compound Analysis To Discriminate Between Nonvaccinated And Bcg-Vaccinated Cattle Prior To And After Mycobacterium Bovis Challenge, Christine K. Ellis, Somchai Rice, Devin Maurer, Randal S. Stahl, W. Ray Waters, Mitchell V. Palmer, Pauline Nol, Jack C. Rhyan, Kurt C. Vercauteren, Jacek A. Koziel

United States Department of Agriculture Wildlife Services: Staff Publications

Bovine tuberculosis is a zoonotic disease of global public health concern. Development of diagnostic tools to improve test accuracy and efficiency in domestic livestock and enable surveillance of wildlife reservoirs would improve disease management and eradication efforts. Use of volatile organic compound analysis in breath and fecal samples is being developed and optimized as a means to detect disease in humans and animals. In this study we demonstrate that VOCs present in fecal samples can be used to discriminate between non-vaccinated and BCG-vaccinated cattle prior to and after Mycobacterium bovis challenge.

Estimating Population Density For Disease Risk Assessment: The Importance Of Understanding The Area Of Influence Of Traps Using Wild Pigs As An Example, Amy J. Davis, Bruce Leland, Michael J. Bodenchuk, Kurt C. Vercauteren, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Population density is a key driver of disease dynamics in wildlife populations. Accurate disease risk assessment and determination of management impacts on wildlife populations requires an ability to estimate population density alongside management actions. A common management technique for controlling wildlife populations to monitor and mitigate disease transmission risk is trapping (e.g., box traps, corral traps, drop nets). Although abundance can be estimated from trapping actions using a variety of analytical approaches, inference is limited by the spatial extent to which a trap attracts animals on the landscape. If the “area of influence” were known, abundance estimates could be converted …

Control Of Invasive Rats On Islands And Priorities For Future Action, Quiterie Duron, Aaron B. Shiels, Eric Vidal

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive rats are one of the world’s most successful animal groups that cause native species extinctions and ecosystem change, particularly on islands. On large islands, rat eradication is often impossible and population control, defined as the local limitation of rat abundance, is now routinely performed on many of the world’s islands as an alternative management tool. However, a synthesis of the motivations, techniques, costs, and outcomes of such rat-control projects is lacking. We reviewed the literature, searched relevant websites, and conducted a survey via a questionnaire to synthesize the available information on rat-control projects in island natural areas worldwide to …

Studies Of Wolf X Coyote Hybridization Via Artificial Insemination, L. David Mech, Cheryl S. Asa, Margaret Callahan, Bruce W. Christensen, Fran Smith, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Following the production of western gray wolf (Canis lupus) x western coyote (Canis latrans) hybrids via artificial insemination (AI), the present article documents that the hybrids survived in captivity for at least 4 years and successfully bred with each other. It further reports that backcrossing one of the hybrids to a male gray wolf by AI also resulted in the birth of live pups that have survived for at least 10 months. All male hybrids (F₁ and F₂) produced sperm by about 10 months of age, and sperm quality of the F_{1 …}

Differential Impacts Of Wildfire On The Population Dynamics Of An Old-Forest Species, Jeremy T. Rockweit, Alan B. Franklin, Peter C. Carlson

United States Department of Agriculture Wildlife Services: Staff Publications

Ecological disturbances shape and maintain natural communities, but climate change and human land use can alter disturbance regimes and affect population persistence and vital rates in unpredictable ways. Species inhabiting landscapes shaped by wildfire have evolved mechanisms allowing them to persist under this dynamic disturbance type, which creates habitats of varying quality for these species. We utilized data from a 26-yr demographic study of northern spotted owls to analyze the influence of wildfire on apparent survival and recruitment rates. Wildfires occurred across different years and affected different spotted owl territories, which allowed us to implement a retrospective Before-After-Control-Impact (BACI) analysis …

Transmission Of H6n2 Wild Bird-Origin Influenza A Virus Among Multiple Bird Species In A Stacked-Cage Setting, J. Jeffrey Root, Susan A. Shriner, Jeremy W. Ellis, Kaci K. Vandalen, Alan B. Franklin

United States Department of Agriculture Wildlife Services: Staff Publications

Live bird markets are common in certain regions of the U.S. and in other regions of the world. We experimentally tested the ability of a wild bird influenza A virus to transmit from index animals to naive animals at varying animal densities in stacked cages in a simulated live bird market. Two and six mallards, five and twelve quail, and six and nine pheasants were used in the low-density and high-density stacks of cages, respectively. Transmission did not occur in the high-density stack of cages likely due to the short duration and relatively low levels of shedding, a dominance of …

Investigation Of Techniques To Measure Cortisol And Testosterone Concentrations In Coyote Hair, Christopher J. Schell, Julie K. Young, Elizabeth V. Lonsdorf, Jill M. Mateo, Rachel M. Santymire

United States Department of Agriculture Wildlife Services: Staff Publications

Long-term noninvasive sampling for endangered or elusive species is particularly difficult due to the challenge of collecting fecal samples before hormone metabolite desiccation, as well as the difficulty in collecting a large enough sample size from all individuals. Hair samples may provide an environmentally stable alternative that provides a long-term assessment of stress and reproductive hormone profiles for captive, zoo, and wild mammals. Here, we extracted and analyzed both cortisol and testosterone in coyote (Canis latrans) hair for the first time. We collected samples from 5-week old coyote pups (six female, six male) housed at the USDA-NWRC Predator …

Different Prey Resources Suggest Little Competition Between Non-Native Frogs And Insectivorous Birds Despite Isotopic Niche Overlap, Robyn L. Smith, Karen H. Beard, Aaron B. Shiels

United States Department of Agriculture Wildlife Services: Staff Publications

Non-native amphibians often compete with native amphibians in their introduced range, but their competitive effects on other vertebrates are less well known. The Puerto Rican coqui frog (Eleutherodactylus coqui) has colonized the island of Hawaii, and has been hypothesized to compete with insectivorous birds and bats. To address if the coqui could compete with these vertebrates, we used stable isotope analyses to compare the trophic position and isotopic niche overlap between the coqui, three insectivorous bird species, and the Hawaiian hoary bat. Coquis shared similar trophic position to Hawaii amakihi, Japanese white-eye, and red-billed leiothrix. Coquis were about …

Anthropogenic Factors Predict Movement Of An Invasive Species, Michael A. Tabak, Antoinette J. Piaggio, Ryan S. Miller, Rick A. Sweitzer, Holly B. Ernest

United States Department of Agriculture Wildlife Services: Staff Publications

Humans are playing an increasingly large role in the expansion of invasive species’ distributions, but few (if any) studies have evaluated anthropogenic factors associated with intentional translocation of invasives. The wild pig (Sus scrofa) is an extremely destructive and rapidly expanding invasive species whose movement is thought to be facilitated by humans.We sought to (1) identify a suite of genetic markers that can be applied to population genetic analyses of wild pigs, (2) find quantitative evidence of human-mediated dispersal of wild pigs, and (3) determine which anthropogenic factors were associated with their translocation. We identified 43 polymorphic microsatellite …

Greater Sage-Grouse Nest Survival In Northwestern Wyoming, Jimmy D. Taylor Ii, R. Douglas Holt, Elizabeth K. Orning, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Nest survival, along with female survival and chick survival, is the most important vital rates to population growth of greater sage-grouse (Centrocercus urophasianus; sage-grouse). We used global positioning system and very high-frequency transmitters on female sage-grouse to identify 204 nests and monitor incubation on 5 sites in the Bighorn Basin, Wyoming from 2011 to 2014; we determined nest fate and identified predators with camera traps. We used an information-theoretic approach to compare 6 a priori nest survival models. Nest survival was best described by a model that included differences across study sites and ranged from 0.20±0.01 (SE) to …

Den Use And Heterothermy During Winter In Free-Living, Suburban Striped Skunks, Tad C. Theimer, Cory T. Williams, Shylo R. Johnson, Amy T. Gilbert, David L. Bergman, C. Loren Buck

United States Department of Agriculture Wildlife Services: Staff Publications

Many mammals use heterothermy to meet challenges of reduced food availability and low temperatures, but little is known about the prevalence of heterothermy in wild mesocarnivores. We monitored body temperature (T_b) in free-living striped skunks (Mephitis mephitis) through winter 2015–2016 in suburban Flagstaff, Arizona, a high-elevation site that experiences temperate winters. Subcutaneous T_b and heterothermy index (HI) were significantly affected by ambient temperature, and varied significantly across 7 skunks in midwinter. Twenty-one of 36 (58%) unique diurnal dens used by skunks were associated with human structures, and although females were found in dens under houses …

Shifts In An Invasive Rodent Community Favoring Black Rats (Rattus Rattus) Following Restoration Of Native Forest, Aaron B. Shiels, Arthur Medeiros, Erica I. Von Allmen

United States Department of Agriculture Wildlife Services: Staff Publications

One potential, unintended ecological consequence accompanying forest restoration is a shift in invasive animal populations, potentially impacting conservation targets. Eighteen years after initial restoration (ungulate exclusion, invasive plant control, and out planting native species) at a 4 ha site on Maui, Hawai‘i, we compared invasive rodent communities in a restored native dry forest and adjacent non-native grassland. Quarterly for 1 year, we trapped rodents on three replicate transects (107 rodent traps) in each habitat type for three consecutive nights. While repeated trapping may have reduced the rat (Black rat, Rattus rattus) population in the forest, it did not appear …

Comment On: ‘Blood Does Not Buy Goodwill: Allowing Culling Increases Poaching Of A Large Carnivore’, Kim M. Pepin, Shannon L. Kay, Amy J. Davis

United States Department of Agriculture Wildlife Services: Staff Publications

Chapron & Treves [1] present a framework for examining effects of wolf culling policies on wolf population growth rate. They develop a population growth model that estimates an effect of the amount of time per year legal culling is allowed (‘policy effect’) on wolf population growth rates, separate from an effect of culling. They infer that there is substantial evidence for a negative relationship between the proportion of the year that the culling policy is in effect and the population growth rate because 83% of the posterior distribution for the policy effect parameter was negative. They conclude that when it …