Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

United States Department of Agriculture Wildlife Services: Staff Publications

Discipline
Keyword
Publication Year
File Type

Articles 991 - 1020 of 1530

Full-Text Articles in Life Sciences

Reproductive Characteristics Of Double-Crested Cormorants (Phalacrocorax Auritus) In The Eastern United States: Demographic Information For An Intensely Managed Species, Brian S. Dorr, Katie C. Hanson-Dorr, Scott C. Barras, Travis L. Devault Jan 2016

Reproductive Characteristics Of Double-Crested Cormorants (Phalacrocorax Auritus) In The Eastern United States: Demographic Information For An Intensely Managed Species, Brian S. Dorr, Katie C. Hanson-Dorr, Scott C. Barras, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Double-crested Cormorants (Phalacrocorax auritus) are intensely managed through culling in North America to reduce presumed damage to commercial and natural resources. To evaluate this management, there is a critical need to understand the reproductive biology of Double-crested Cormorants. Gonadal development, reproductive potential and breeding status were determined by necropsy for 1,781 Double-crested Cormorants salvaged each month of the year from control programs in their wintering and breeding ranges in seven States in the USA. Gonadal development of males peaked earlier in the year than females. Mean and maximum reproductive potential was five and 13 ovum, respectively. The average …

Go to article

Use Of Predator Hair To Enhance Perceived Risk To White-Tailed Deer In A Foraging Context, Thomas W. Seamans, Bradley F. Blackwell, Kimberly E. Linnell Jan 2016

Use Of Predator Hair To Enhance Perceived Risk To White-Tailed Deer In A Foraging Context, Thomas W. Seamans, Bradley F. Blackwell, Kimberly E. Linnell

United States Department of Agriculture Wildlife Services: Staff Publications

Deer react to predator scent in varying degrees even when exposed to unknown predators. This response could be genetically based and maintained as long as the population is exposed to predation. We tested whether predator scent in the form of hair would enhance perceived risk and serve as a foraging repellent to free-ranging white-tailed deer (Odocoileus virginianus). During the winters of 2013 and 2014, we quantifi ed alert behaviors and consumption of whole-kernel corn in response to current (coyote [Canis latrans]) and extirpated (bobcat [Lynx rufus]; black bear [Ursus americanus]) predator species …

Go to article

Evaluating Wildlife-Cattle Contact Rates To Improve The Understanding Of Dynamics Of Bovine Tuberculosis Transmission In Michigan, Usa, Michael J. Lavelle, Shannon L. Kay, Kim M. Pepin Jan 2016

Evaluating Wildlife-Cattle Contact Rates To Improve The Understanding Of Dynamics Of Bovine Tuberculosis Transmission In Michigan, Usa, Michael J. Lavelle, Shannon L. Kay, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Direct and indirect contacts among individuals drive transmission of infectious disease. When multiple interacting species are susceptible to the same pathogen, risk assessment must include all potential host species. Bovine tuberculosis (bTB) is an example of a disease that can be transmitted among several wildlife species and to cattle, although the potential role of several wildlife species in spillback to cattle remains unclear. To better understand the complex network of contacts and factors driving disease transmission, we fitted proximity logger collars to beef and dairy cattle (n = 37), white-tailed deer (Odocoileus virginianus; n=29), raccoon (Procyon lotor; n=53), and Virginia …

Go to article

Repellent Application Strategy For Wild Rodents And Cottontail Rabbits, Scott J. Werner, Shelagh T. Deliberto, Roger A. Baldwin, Gary W. Witmer Jan 2016

Repellent Application Strategy For Wild Rodents And Cottontail Rabbits, Scott J. Werner, Shelagh T. Deliberto, Roger A. Baldwin, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Effective chemical repellents and repellent application strategies are needed to manage damages caused by wild rodents and rabbits to agricultural resources. For the purpose of comparatively investigating the behavioral response of wild rodents and rabbits to a chemical repellent, we experimentally evaluated the concentration-response relationship of an anthraquinone-based repellent in California voles (Microtus californicus Peale), Richardson’s ground squirrels (Urocitellus richardsonii Sabine), deer mice (Peromyscus maniculatus Wagner) and cottontail rabbits (Sylvilagus audubonii Baird) in captivity. We observed 52–56% feeding repellency for whole oats treated with 10,800ppm anthraquinone or 18,500ppmanthraquinone in mice and squirrels, and 84–85% repellency for …

Go to article

Novel And Current Rodenticides For Pocket Gopher Thomomys Spp. Management In Vineyards: What Works?, Roger A. Baldwin, Ryan Meinerz, Gary W. Witmer Jan 2016

Novel And Current Rodenticides For Pocket Gopher Thomomys Spp. Management In Vineyards: What Works?, Roger A. Baldwin, Ryan Meinerz, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

BACKGROUND: Rodenticides are often included as part of an integrated pest management approach for managing pocket gophers (Thomomys spp.) given that they are relatively quick and inexpensive to apply. Strychnine has historically been the most effective toxicant for pocket gophers, but its use is currently limited in the United States; alternative registered toxicants have not proven effective. Recent research with baits containing cholecalciferol plus anticoagulant toxicants proved effective against pocket gophers in a lab setting. Therefore, we established a field study to compare cholecalciferol plus anticoagulant combinations [0.03% cholecalciferol plus 0.005% diphacinone (C+D), 0.015% cholecalciferol plus 0.0025% brodifacoum (C+B1), …

Go to article

Weak Support For Disappearance And Restricted Emergence/Persistence Of Highly Pathogenic Influenza A In North American Waterfowl, Andrew M. Ramey, Erica Spackman, Mia Kim-Torchetti, Thomas J. Deliberto Jan 2016

Weak Support For Disappearance And Restricted Emergence/Persistence Of Highly Pathogenic Influenza A In North American Waterfowl, Andrew M. Ramey, Erica Spackman, Mia Kim-Torchetti, Thomas J. Deliberto

United States Department of Agriculture Wildlife Services: Staff Publications

Krauss et al. (1) use lack of detection of highly pathogenic (HP) H5 clade 2.3.4.4 (henceforth “H5”) influenza A viruses (IAVs) from >22,000 wild bird samples collected in North America in 2014–2015 to argue that HP H5 IAVs disappeared from waterfowl and that unresolved mechanisms restrict emergence and perpetuation of HP IAVs in natural reservoir species. Here we offer an alternative interpretation.

Go to article

Effects Of Visual Obstruction, Prey Resources, And Satiety On Bird Use Of Simulated Airport Grasslands, Bradley F. Blackwell, Thomas W. Seamans, Kimberly Linnell, Lisa Kutschbach-Brohl, Travis L. Devault Jan 2016

Effects Of Visual Obstruction, Prey Resources, And Satiety On Bird Use Of Simulated Airport Grasslands, Bradley F. Blackwell, Thomas W. Seamans, Kimberly Linnell, Lisa Kutschbach-Brohl, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Grasslands represent 39%–50% of U.S. airport properties, and a recent management framework recommended exploiting both antipredator behaviours and food resources in airport grasslands to curb use by birds considered hazardous to aviation safety. We evaluated framework predictions empirically by exposing unsated and sated brown-headed cowbirds (Molothrus ater) to visually obstructive (∼13-cm vegetation height; tall), higher-risk plots versus unobstructive (height; short) plots, and relative to prey resources. We predicted that 1) unsated birds (unfed since the previous day) would be present in greater numbers and forage more in short than tall vegetation plots 24 h post-mowing because of invertebrate …

Go to article

Inferring Invasive Species Abundance Using Removal Data From Management Actions, Amy J. Davis, Mevin B. Hooten, Ryan S. Miller, Matthew L. Farnsworth, Jesse Lewis, Michael Moxcey, Kim M. Pepin Jan 2016

Inferring Invasive Species Abundance Using Removal Data From Management Actions, Amy J. Davis, Mevin B. Hooten, Ryan S. Miller, Matthew L. Farnsworth, Jesse Lewis, Michael Moxcey, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Evaluation of the progress of management programs for invasive species is crucial for demonstrating impacts to stakeholders and strategic planning of resource allocation. Estimates of abundance before and after management activities can serve as a useful metric of population management programs. However, many methods of estimating population size are too labor intensive and costly to implement, posing restrictive levels of burden on operational programs. Removal models are a reliable method for estimating abundance before and after management using data from the removal activities exclusively, thus requiring no work in addition to management. We developed a Bayesian hierarchical model to estimate …

Go to article

Pathogen Emergence In The Age Of Pandemics, Sarah N. Bevins Jan 2016

Pathogen Emergence In The Age Of Pandemics, Sarah N. Bevins

United States Department of Agriculture Wildlife Services: Staff Publications

The emergence of novel or previously rare pathogens is not new. Throughout recorded history, catastrophic mortality has followed the arrival of new infectious diseases to areas that had no previous experience with the offending agent. The second plague pandemic, more commonly known as the Black Death, was caused by a bacterium that originated in China but then spread throughout Asia, Europe, and Africa via the Silk Road and other routes of commerce. The emergence of rinderpest in Africa, associated with Asian cattle imported by European colonists, killed millions of domestic livestock and wild animal species in the 1890s. The result …

Go to article

Improving The Odds: Assessing Bait Availability Before Rodent Eradications To Aid In Selecting Bait Application Rates, Madeleine Pott, Alexander S. Wegmann, Richard Griffiths, Araceli Samaniego-Herrera, Richard J. Cuthbert, M. De L. Brooke, William C. Pitt, Are R. Berentsen, Nick D. Holmes, Gregg R. Howald, Karina Ramos-Rendon, James C. Russell Nov 2015

Improving The Odds: Assessing Bait Availability Before Rodent Eradications To Aid In Selecting Bait Application Rates, Madeleine Pott, Alexander S. Wegmann, Richard Griffiths, Araceli Samaniego-Herrera, Richard J. Cuthbert, M. De L. Brooke, William C. Pitt, Are R. Berentsen, Nick D. Holmes, Gregg R. Howald, Karina Ramos-Rendon, James C. Russell

United States Department of Agriculture Wildlife Services: Staff Publications

Rodent eradications undertaken on tropical islands are more likely to fail than eradications undertaken at higher latitudes. We report on 12 independent rodent eradication projects undertaken on tropical islands that utilized the results of an in situ bait availability study prior to eradication to inform, a priori, the bait application rate selected for the eradication. These projects also monitored bait availability during the eradication. The results from our analysis verified the utility of bait availability studies to future rodent eradication campaigns and confirmed the influence of two environmental factors that can affect bait availability over time: precipitation prior to the …

Go to article

Human Disturbance And The Physiological Response Of Elk In Eastern Washington, D. S. Jachowski, S. Mccorquodale, Brian E. Washburn, Joshua J. Millspaugh Jun 2015

Human Disturbance And The Physiological Response Of Elk In Eastern Washington, D. S. Jachowski, S. Mccorquodale, Brian E. Washburn, Joshua J. Millspaugh

United States Department of Agriculture Wildlife Services: Staff Publications

Stress hormone measures have proven useful for assessing effects of human disturbance on wildlife populations. However, most studies are of short duration or limited geographic scope (i.e., without spatial replication), leading to concerns about confounding effects of biotic conditions. Previous research correlated fecal glucocorticoid metabolites (FGMs) of elk (Cervus elaphus) with human disturbance, but this factor also co-varied with seasonal climatic conditions, making it difficult to make broader inference regarding the role of human disturbance. In this study we attempted to simultaneously evaluate the effects of climatic conditions and human disturbance by comparing the year-round physiological stress response …

Go to article

Fecal Volatile Organic Ccompound Profiles From White-Tailed Deer (Odocoileus Virginianus) As Indicators Of Mycobacterium Bovis Exposure Or Mycobacterium Bovis Bacille Calmette-Guerin (Bcg) Vaccination, Randal S. Stahl, Christine K. Ellis, Pauline Nol, W. Ray Waters, Kurt C. Vercauteren Jun 2015

Fecal Volatile Organic Ccompound Profiles From White-Tailed Deer (Odocoileus Virginianus) As Indicators Of Mycobacterium Bovis Exposure Or Mycobacterium Bovis Bacille Calmette-Guerin (Bcg) Vaccination, Randal S. Stahl, Christine K. Ellis, Pauline Nol, W. Ray Waters, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

White-tailed deer (Odocoileus virginianus) serve as a reservoir for bovine tuberculosis, caused by Mycobacterium bovis, and can be a source of infection in cattle. Vaccination with M. bovis Bacille Calmette Guerin (BCG) is being considered for management of bovine tuberculosis in deer. Presently, no method exists to non-invasively monitor the presence of bovine tuberculosis in deer. In this study, volatile organic compound profiles of BCG-vaccinated and non-vaccinated deer, before and after experimental challenge with M. bovis strain 95–1315, were generated using solid phase microextraction fiber head-space sampling over suspended fecal pellets with analysis by gas chromatography/mass spectrometry. …

Go to article

Cowbird Responses To Aircraft With Lights Tuned To Their Eyes: Implications For Bird–Aircraft Collisions, Megan S. Doppler, Bradley F. Blackwell, Travis L. Devault, Esteban Fernández-Juricic Apr 2015

Cowbird Responses To Aircraft With Lights Tuned To Their Eyes: Implications For Bird–Aircraft Collisions, Megan S. Doppler, Bradley F. Blackwell, Travis L. Devault, Esteban Fernández-Juricic

United States Department of Agriculture Wildlife Services: Staff Publications

Collisions between birds and aircraft (bird strikes) are expensive, risk human lives, and increase bird mortality. Aircraft lighting has been proposed as a potential means of enhancing avian responses to aircraft. Determining the optimal changes to lighting to reduce bird strikes is a complicated problem because avian visual systems differ markedly from that of humans. Icteridae, including Brown-headed Cowbirds (Molothrus ater; hereafter ‘‘cowbirds’’), are involved in bird strikes, have a well-described visual system, and respond to approaching vehicles and lights. Our goal was to assess cowbirds’ responses to a remote-controlled (RC) aircraft fitted with lights tuned to the …

Go to article

Capillaria Hepatica Infection In Black Rats (Rattus Rattus) On Diego Garcia, British Indian Ocean Territory, Are R. Berentsen, Scott Vogt, Antenor N. Guzman, Daniel S. Vice, William C. Pitt, Aaron B. Shiels, Terry R. Spraker Jan 2015

Capillaria Hepatica Infection In Black Rats (Rattus Rattus) On Diego Garcia, British Indian Ocean Territory, Are R. Berentsen, Scott Vogt, Antenor N. Guzman, Daniel S. Vice, William C. Pitt, Aaron B. Shiels, Terry R. Spraker

United States Department of Agriculture Wildlife Services: Staff Publications

Rats (Rattus spp.) are among the most damaging invasive species worldwide. The accidental introduction of rats has caused significant detriment to native flora and fauna, crops, structures, and human livelihoods. Rats are vectors of disease and carriers of various zoonotic parasites. Capillaria hepatica (syn. Callodium hepaticum) is a parasitic nematode found primarily in rodents but is known to infect over 140 mammal species, including human beings and several species of domestic animals. In this case study, the presence of C. hepatica infection in black rats on Diego Garcia, British Indian Ocean Territory, is reported. Liver samples from …

Go to article

Novel Paramyxoviruses In Bats From Sub-Saharan Africa, 2007–2012, Marinda Mortlock, Ivan V. Kuzmin, Jacqueline Weyer, Amy T. Gilbert, Bernard Agwanda, Charles E. Rupprecht, Louis H. Nel, Teresa Kearney, Jean M. Malekani, Wanda Markotter Jan 2015

Novel Paramyxoviruses In Bats From Sub-Saharan Africa, 2007–2012, Marinda Mortlock, Ivan V. Kuzmin, Jacqueline Weyer, Amy T. Gilbert, Bernard Agwanda, Charles E. Rupprecht, Louis H. Nel, Teresa Kearney, Jean M. Malekani, Wanda Markotter

United States Department of Agriculture Wildlife Services: Staff Publications

As part of a larger survey for detection of pathogens among wildlife in sub-Saharan Africa conducted during 2007–2012, multiple diverse paramyxovirus sequences were detected in renal tissues of bats. Phylogenetic analysis supports the presence of at least 2 major viral lineages and suggests that paramyxoviruses are strongly associated with several bat genera.

Go to article

Underreporting Of Wildlife-Vehicle Collisions Does Not Hinder Predictive Models For Large Ungulates, Nathan P. Snow, William F. Porter, David M. Williams Jan 2015

Underreporting Of Wildlife-Vehicle Collisions Does Not Hinder Predictive Models For Large Ungulates, Nathan P. Snow, William F. Porter, David M. Williams

United States Department of Agriculture Wildlife Services: Staff Publications

Conflicts from wildlife–vehicle collisions (WVCs) pose serious challenges for managing and conserving large ungulates throughout the world. However, underreporting of large proportions of WVCs (i.e., two-thirds of WVCs in some cases) creates concern for relying on governmental databases to inform management strategies of WVCs. Our objective was to test the sensitivity of WVC studies to underreporting using 2 species of large ungulates that experience substantial incidences of collisions but exist in different environmental settings: white-tailed deer (Odocoileus virginianus) in agricultural-dominated central Illinois and moose (Alces alces) in forest-dominated western Maine, USA. We estimated baseline relationships between …

Go to article

Seasonal Shifts In Diet And Gut Microbiota Of The American Bison (Bison Bison), Gaddy T. Bergmann, Joseph Craine, Michael S. Robeson, Noah Fierer Jan 2015

Seasonal Shifts In Diet And Gut Microbiota Of The American Bison (Bison Bison), Gaddy T. Bergmann, Joseph Craine, Michael S. Robeson, Noah Fierer

United States Department of Agriculture Wildlife Services: Staff Publications

North American bison (Bison bison) are becoming increasingly important to both grassland management and commercial ranching. However, a lack of quantitative data on their diet constrains conservation efforts and the ability to predict bison effects on grasslands. In particular, we know little about the seasonality of the bison diet, the degree to which bison supplement their diet with eudicots, and how changes in diet influence gut microbial communities, all of which play important roles in ungulate performance. To address these knowledge gaps, we quantified seasonal patterns in bison diet and gut microbial community composition for a bison herd in …

Go to article

Spatiotemporal Dynamics In Identification Of Aircraft–Bird Strikes, Tara J. Conkling, James A. Martin, Jerrold L. Belant, Travis L. Devault Jan 2015

Spatiotemporal Dynamics In Identification Of Aircraft–Bird Strikes, Tara J. Conkling, James A. Martin, Jerrold L. Belant, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

A primary concern for human–wildlife interactions is the potential impacts resulting from wildlife (primarily birds) collisions with aircraft. The identification of species responsible for collisions with aircraft is necessary so that airport management can develop effective strategies to reduce strikes with those species. Of particular importance in developing such strategies is the identification of regional, seasonal, and temporal patterns in collisions with unidentified bird species that may limit the effectiveness of regional habitat management to reduce bird strikes. The authors analyzed 105,529 U.S. civil aviation strike records from 1990 to 2012 in the FAA’s National Wildlife Strike Database to examine …

Go to article

Managing Hybridization Of A Recovering Endangered Species: The Red Wolf Canis Rufus As A Case Study, Eric M. Gese, Fred F. Knowlton, Jennifer R. Adams, Karen Beck, Todd K. Fuller, Dennis L. Murray, Todd D. Steury, Michael K. Stoskopf, Will T. Waddell, Lisette P. Waits Jan 2015

Managing Hybridization Of A Recovering Endangered Species: The Red Wolf Canis Rufus As A Case Study, Eric M. Gese, Fred F. Knowlton, Jennifer R. Adams, Karen Beck, Todd K. Fuller, Dennis L. Murray, Todd D. Steury, Michael K. Stoskopf, Will T. Waddell, Lisette P. Waits

United States Department of Agriculture Wildlife Services: Staff Publications

Hybridization presents a unique challenge for conservation biologists and managers. While hybridization is an important evolutionary process, hybridization is also a threat formany native species. The endangered species recovery effort for the red wolf Canis rufus is a classic system for understanding and addressing the challenges of hybridization. From 1987‒1993, 63 red wolves were released from captivity in eastern North Carolina, USA, to establish a free-ranging, non-essential experimental population. By 1999, managers recognized hybridization with invasive coyotes Canis latrans was the single greatest threat to successful recovery, and an adaptive management plan was adopted with innovative approaches for managing the …

Go to article

Thermal Fumigation Provides A Simple And Effective Solution For Sanitizing Cargo From Invasive Snakes, Fred Kraus, Randal S. Stahl, William Pitt Jan 2015

Thermal Fumigation Provides A Simple And Effective Solution For Sanitizing Cargo From Invasive Snakes, Fred Kraus, Randal S. Stahl, William Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

The Brown Treesnake (Boiga irregularis) is invasive in Guam and threatens to be dispersed by military and civilian transportation activities to other islands in the Pacific, where it could be expected to inflict similar damages. Prevention of inadvertent export of snakes in cargo and vehicles currently relies on trained canine detection teams, which are expensive to use and unable to detect all snakes. Hence, there has long been interest in developing effective and cheaper means of fumigating cargo to remove snakes. A companion study has shown that chemical fumigation is unlikely to be readily developed into a practical …

Go to article

Tropical Forest Responses To Large-Scale Experiments, Aaron B. Shiels, Grizelle Gonzalez Jan 2015

Tropical Forest Responses To Large-Scale Experiments, Aaron B. Shiels, Grizelle Gonzalez

United States Department of Agriculture Wildlife Services: Staff Publications

Although artificial by nature, experiments are a necessary part of ecology if we are to understand key mechanisms driving ecosystem structure and function. Experiments range in scale from microscopic to landscape; large-scale experiments are typically more logistically challenging than are small-scale experiments or observational studies. Recently, researchers have been interested in utilizing large-scale experiments to determine how forests respond to environmental change. Large-scale experiments have been more common in temperate than in tropical forests, yet tropical forests contain over half of the world’s species in just 7 percent of the world’s land area. Key threats to tropical biodiversity, such as …

Go to article

Human–Carnivore Interactions: Lessons Learned From Communities In The American West, Julie K. Young, Zhao Ma, Ann Laudati, Joel Berger Jan 2015

Human–Carnivore Interactions: Lessons Learned From Communities In The American West, Julie K. Young, Zhao Ma, Ann Laudati, Joel Berger

United States Department of Agriculture Wildlife Services: Staff Publications

Types, causes, and intensity of human–carnivore interactions are related to historical context, management policy, and human perception. We used four rural communities in the American West with varying histories and management policies to assess the complexities of human–carnivore interactions and to determine factors influencing individual willingness to coexist with carnivores. By analyzing focus group and interview data from 49 community members, we found that human perceptions towards carnivores and their management were influenced by self-perceived knowledge about carnivores, ability to be heard and have a voice in management decisions, and economic concerns rather than ecological factors. Willingness to coexist with …

Go to article

Cascading Effects Of Canopy Opening And Debris Deposition From A Large-Scale Hurricane Experiment In A Tropical Rain Forest, Aaron B. Shiels, Grizelle Gonzalez, D. Jean Lodge, Michael R. Willig, Jess K. Zimmerman Jan 2015

Cascading Effects Of Canopy Opening And Debris Deposition From A Large-Scale Hurricane Experiment In A Tropical Rain Forest, Aaron B. Shiels, Grizelle Gonzalez, D. Jean Lodge, Michael R. Willig, Jess K. Zimmerman

United States Department of Agriculture Wildlife Services: Staff Publications

Intense hurricanes disturb many tropical forests, but the key mechanisms driving post-hurricane forest changes are not fully understood. In Puerto Rico, we used a replicated factorial experiment to determine the mechanisms of forest change associated with canopy openness and organic matter (debris) addition. Cascading effects from canopy openness accounted for most of the shifts in the forest biota and biotic processes, which included increased plant recruitment and richness, as well as the decreased abundance and diversity of several animal groups. Canopy opening decreased litterfall and litter moisture, thereby inhibiting lignin-degrading fungi, which slowed decomposition. Debris addition temporarily increased tree basal …

Go to article

Ecological Role Of Vertebrate Scavengers, James C. Beasley, Zach H. Olson, Travis L. Devault Jan 2015

Ecological Role Of Vertebrate Scavengers, James C. Beasley, Zach H. Olson, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Scavenging, or the consumption of dead animal matter, has been documented for a wide array of vertebrate taxa by naturalists and researchers for centuries. Yet, until recently, the importance of scavenging-derived nutrients to many vertebrate species has been largely unknown (DeVault et a1. 2003; Beasley et al. 2012b; Barton et al. 2013). As a result, the role vertebrate scavenging plays in food-web dynamics relative to that of microbes and invertebrates has been greatly underestimated (Wilson and Wolkovich 2011) and has thus become an important area of research. Indeed, in some ecosystems, vertebrates have been documented to assimilate as much as …

Go to article

Efficacy Of Potential Chemical Control Compounds For Removing Invasive American Bullfrogs (Rana Catesbeiana), Gary W. Witmer, Nathan P. Snow, Rachael S. Moulton Jan 2015

Efficacy Of Potential Chemical Control Compounds For Removing Invasive American Bullfrogs (Rana Catesbeiana), Gary W. Witmer, Nathan P. Snow, Rachael S. Moulton

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive American bullfrogs [Rana catesbeiana (Lithobates catesbeianus)] are outcompeting and predating on native biota and contributing to reductions in biodiversity worldwide. Current methods for controlling American bullfrogs are incapable of stopping their expansion, thus more cost-effective and broadly applicable methods are needed. Although chemical control compounds have been identified as effective for removing other invasive amphibians, none have been tested for American bullfrogs. Our objective was to expand on previous research and test the efficacy of 10 potential chemical control compounds for removing invasive American bullfrogs. After a dermal spray-application of 4 ml, we found 3 compounds (i.e., chloroxylenol, rotenone …

Go to article

Flight Feather Molt In Yellow-Headed Blackbirds (Xanthocephalus Xanthocephalus) In North Dakota, Daniel J. Twedt, George M. Linz Jan 2015

Flight Feather Molt In Yellow-Headed Blackbirds (Xanthocephalus Xanthocephalus) In North Dakota, Daniel J. Twedt, George M. Linz

United States Department of Agriculture Wildlife Services: Staff Publications

Yellow-headed Blackbirds (Xanthocephalus xanthocephalus) in central North Dakota undergo prebasic molt or prejuvenile molt during late summer. Nestling Yellow-headed Blackbirds initiate a complete prejuvenile molt, grow their primary and secondary regimes in about 40 days, completing molt after they leave the nest by the first week in August. Remiges are not replaced during the subsequent preformative molt, being retained until the second prebasic molt. Nonlinear (logistic) regression of primary remex growth during definitive prebasic molts of Yellow-headed Blackbirds indicated 38 days were required to complete the linear phase of growth (between 10% and 90% of total primary length). Males added …

Go to article

Invaded Invaders: Infection Of Invasive Brown Treesnakes On Guam By An Exotic Larval Cestode With A Life Cycle Comprised Of Non-Native Hosts, Elden T. Holldorf, Shane R. Siers, Jonathan Q. Richmond, Page E. Klug, Robert N. Reed Jan 2015

Invaded Invaders: Infection Of Invasive Brown Treesnakes On Guam By An Exotic Larval Cestode With A Life Cycle Comprised Of Non-Native Hosts, Elden T. Holldorf, Shane R. Siers, Jonathan Q. Richmond, Page E. Klug, Robert N. Reed

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Multiple host introductions to the same non-native environment have the potential to complete life cycles of parasites incidentally transported with them. Our goal was to identify a recently detected parasitic flatworm in the invasive Brown Treesnake (Boiga irregularis) on the remote Pacific island of Guam. We considered possible factors influencing parasite transmission, and tested for correlations between infection status and potential indicators of host fitness. We used genetic data from the parasite and information about the native ranges of other possible non-native hosts to hypothesize how it arrived on Guam and how its life cycle may be …

Go to article

Impact Of Capture And Transportation Methods On Survival Of Small Rodents During Relocation Events, Roger A. Baldwin, Ryan Meinerz, Holly E. Jantz, Gary W. Witmer Jan 2015

Impact Of Capture And Transportation Methods On Survival Of Small Rodents During Relocation Events, Roger A. Baldwin, Ryan Meinerz, Holly E. Jantz, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Capture and transportation of wild rodents is needed to supply study animals for laboratory or enclosure studies and for translocation of threatened and endangered species. Stress of captured rodents must be minimized to maximize survival. Methods to limit stress include minimizing capture and transportation durations, providing sufficiently sized housing with adequate nesting materials and foods, and ensuring that animals are maintained in comfortable environmental conditions. We utilized these techniques to capture and transport California voles (Microtus californicus) and pocket gophers (Thomomys bottae) from California to Colorado to determine their rate of survival during this process. We …

Go to article

Evaluation Of Rhodamine B As A Biomarker For Assessing Bait Acceptance In Wild Pigs, James Beasley, Sarah C. Webster, Olin E. Rhodes Jr., Fred L. Cunningham Jan 2015

Evaluation Of Rhodamine B As A Biomarker For Assessing Bait Acceptance In Wild Pigs, James Beasley, Sarah C. Webster, Olin E. Rhodes Jr., Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Worldwide, there is growing interest in the use of pharmaceutical baits to control populations of wild pigs (Sus scrofa). In this study we evaluated the utility of Rhodamine B (RB), a chemical marker commonly used in wildlife research and management, as a potential biomarker for quantifying bait uptake in wild pigs. Thirty wild pigs were live-trapped, transported to a captive facility on the Department of Energy’s Savannah River Site located in South Carolina, USA, during autumn 2013, and administered RB orally at a dosage of 30mg/kg. Eight vibrissae and guard hairs were collected pre- and post-RB exposure (7 …

Go to article

Cwd Prions Remain Infectious After Passage Through The Digestive System Of Coyotes (Canis Latrans), Tracy A. Nichols, Justin W. Fischer, Terry R. Spraker, Qingzhong Kong, Kurt C. Vercauteren Jan 2015

Cwd Prions Remain Infectious After Passage Through The Digestive System Of Coyotes (Canis Latrans), Tracy A. Nichols, Justin W. Fischer, Terry R. Spraker, Qingzhong Kong, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Chronic wasting disease (CWD) is a geographically expanding prion disease of wild and captive cervids in North America. Disease can be transmitted directly, animal to animal, or indirectly via the environment. CWD contamination can occur residually in the environment via soil, water, and forage following deposition of bodily fluids such as urine, saliva, and feces, or by the decomposition of carcasses. Recent work has indicated that plants may even take up prions into the stems and leaves. When a carcass or gut pile is present in the environment, a large number of avian and mammalian species visit and consume the …

Go to article

First Prev Next Last