Natural Resources and Conservation Commons^™

Improving Animal Monitoring Using Small Unmanned Aircraft Systems (Suas) And Deep Learning Networks, Meilun Zhou, Jared A. Elmore, Sathishkumar Samiappan, Kristine O. Evans, Morgan Pfeiffer, Bradley F. Blackwell, Raymond B. Iglay

United States Department of Agriculture Wildlife Services: Staff Publications

In recent years, small unmanned aircraft systems (sUAS) have been used widely to monitor animals because of their customizability, ease of operating, ability to access difficult to navigate places, and potential to minimize disturbance to animals. Automatic identification and classification of animals through images acquired using a sUAS may solve critical problems such as monitoring large areas with high vehicle traffic for animals to prevent collisions, such as animal-aircraft collisions on airports. In this research we demonstrate automated identification of four animal species using deep learning animal classification models trained on sUAS collected images. We used a sUAS mounted with …

Spatial Variation In Direct And Indirect Contact Rates At The Wildlife-Livestock Interface For Informing Disease Management, Anni Yang, Raoul K. Boughton, Ryan S. Miller, Bethany Wight, Wesley M. Anderson, James C. Beasley, Kurt C. Vercauteren, Kim M. Pepin, George Wittemyer

United States Department of Agriculture Wildlife Services: Staff Publications

Little is known about disease transmission relevant contact rates at the wildlife-livestock interface and the factors shaping them. Indirect contact via shared resources is thought to be important but remains unquantified in most systems, making it challenging to evaluate the impact of livestock management practices on contact networks. Free-ranging wild pigs (Sus scrofa) in North America are an invasive, socially-structured species with an expanding distribution that pose a threat to livestock health given their potential to transmit numerous livestock diseases, such as pseudorabies, brucellosis, trichinellosis, and echinococcosis, among many others. Our objective in this study was to quantify …

Plague Exposure In Mammalian Wildlife Across The Western United States, Sarah N. Bevins, Jeffrey C. Chandler, Nicole Barrett, Brandon S. Schmit, Gerald W. Wiscomb, Susan A. Shriner

United States Department of Agriculture Wildlife Services: Staff Publications

Plague is caused by a bacterial pathogen (Yersinia pestis) that can infect a wide range of mammal species, but its presence in wildlife is often underappreciated. Using a large-scale data set (n = 44,857) that details the extent of Y. pestis exposure in wildlife, we document exposure in 18 wildlife species, including coyotes (Canis latrans), bobcats (Lynx rufus), and black bears (Ursus americanus). Evidence of plague activity is widespread, with seropositive animals detected in every western state in the contiguous United States. Pathogen monitoring systems in wildlife that are both large scale …

Data-Driven Management—A Dynamic Occupancy Approach To Enhanced Rabies Surveillance Prioritization, Amy J. Davis, Jordana D. Kirby, Richard B. Chipman, Kathleen M. Nelson, Amy T. Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

Rabies lyssavirus (RABV) is enzootic in raccoons across the eastern United States. Intensive management of RABV by oral rabies vaccination (ORV) has prevented its spread westward and shown evidence of local elimination in raccoon populations of the northeastern US. The USDA, Wildlife Services, National Rabies Management Program (NRMP) collaborates with other agencies to implement broad-scale ORV and conducts extensive monitoring to measure the effectiveness of the management. Enhanced Rabies Surveillance (ERS) was initiated during 2005 and updated in 2016 to direct surveillance efforts toward higher-value specimens by assigning points to different methods of encountering specimens for collection (strange-acting, roadkill, surveillance-trapped, …

Sources And Aftermaths Of Pipeline Related Leaks And Spills, Justin Smith

Symposium of Student Scholars

The escape of oil and other hazardous materials have been shown to pollute and destroy ecosystems. As an aspiring chemist, I am adamant about the secure handling and transportation of oil and other hazardous materials. In the past, researchers have concentrated on oil’s high viscosity. Oil’s high viscosity physically smothers wildlife, affecting their ability to continue critical functions such as respiration, feeding, and thermoregulation. My research focuses on the source of these oil spills, as well as natural gas leaks, for the purpose of risk assessment. In addition, I compare recovery efforts based on the cause of the leak/spill, the …

Monitoring Agroecosystem Productivity And Phenology At A National Scale: A Metric Assessment Framework, Dawn M. Browning, Eric S. Russell, Guillermo E. Ponce-Campos, Nicole Kaplan, Andrew D. Richardson, Bijan Seyednasrollah, Sheri Spiegal, Nicanor Saliendra, Joseph G. Alfieri, John Baker, Carl Bernacchi, Brandon T. Bestelmeyer, David Bosch, Elizabeth H. Boughton, Raoul K. Boughton, Pat Clark, Gerald Flerchinger, Nuria Gomez-Casanovas, Sarah Goslee, Nick M. Haddad, David Hoover, Abdullah Jaradat, Marguerite Mauritz, Gregory W. Mccarty, Gretchen R. Miller, John Sadler, Amartya Saha, Russell L. Scott, Andrew Suyker, Craig Tweedie, Jeffrey D. Wood, Xukai Zhang, Shawn D. Taylor

School of Natural Resources: Faculty Publications

Effective measurement of seasonal variations in the timing and amount of production is critical to managing spatially heterogeneous agroecosystems in a changing climate. Although numerous technologies for such measurements are available, their relationships to one another at a continental extent are unknown. Using data collected from across the Long-Term Agroecosystem Research (LTAR) network and other networks, we investigated correlations among key metrics representing primary production, phenology, and carbon fluxes in croplands, grazing lands, and crop-grazing integrated systems across the continental U.S. Metrics we examined included gross primary productivity (GPP) estimated from eddy covariance (EC) towers and modelled from the Landsat …

Patterns And Drivers Of Introgression In Louisiana's Largemouth Bass (Micropterus Salmoides) Stocks, Colleen E. Walsh

LSU Master's Theses

In the southeastern U.S., populations of the popular sportfish Largemouth Bass (Micropterus salmoides; LMB) are often stocked with Florida Largemouth Bass (Micropterus salmoides floridanus; FLMB) to develop FLMB ancestry in systems north of its native peninsular Florida range, with the ultimate goal of creating trophy fisheries. Stock enhancement through introgression of FLMB ancestry can increase maximum potential size and growth in receiving populations, potentially through hybrid vigor of intergrade subspecies. We collected 60 fish and habitat data from six Louisiana lakes from 2018-2020 (N=360), quantified level of introgression of FLMB with fragment analysis at 12 microsatellite loci confirmed for subspecific …

Effects Of Hunter Movement And Habitat Use On Observation Rate Of White-Tailed Deer (Odocoileus Virginianus), Alyssa N. Meier

Biology Theses, Dissertations, and Student Creative Activity

Hunting by humans is the primary tool for population control for many ungulate species across the United States, including white-tailed deer (Odocoileus virginianus). Previous research has focused primarily on the effects of hunting on prey behavior while neglecting the potential effects hunter behavior has on the probability of harvest success. I examined the influence of hunter movement and habitat use across the landscape on observation rate of white-tailed deer. During the 2008 and 2009 Oklahoma hunting seasons, we recorded GPS and observation data of 83 individual hunters over 487 total hunts. Hunters that moved non-linearly through forested cover at a …

Essays On The Designs And Benefits Of Land Conservation Programs, Badri Khanal

Department of Agricultural Economics: Dissertations, Theses, and Student Research

This dissertation analyzes the policy designs and economic benefits of a land conservation practice called prairie strips. The first chapter investigates the impact of policy designs on individual household preferences. The study measures the value that Iowa residents place on the ecosystem services of prairie strips and determines if that value changes under different policy designs. The policy design treatment varies in who runs the program and who has enrollment priority. The willingness to pay (WTP) for ecosystem services is estimated using stated preferences from a choice experiment. Results indicate significant public support for expanding and funding the prairie strips …

Invader Removal Triggers Competitive Release In A Threatened Avian Predator, J. David Wiens, Katie M. Dugger, J. Mark Higley, Damon B. Lesmeister, Alan B. Franklin, Keith A. Hamm, Gary C. White, Krista E. Dilione, David C. Simon, Robin R. Bown, Peter C. Carlson, Charles B. Yackulic, James D. Nichols, James E. Hines, Raymond J. Davis, David W. Lamphear, Christopher Mccafferty, Trent L. Mcdonald, Stan G. Sovern

United States Department of Agriculture Wildlife Services: Staff Publications

Changes in the distribution and abundance of invasive species can have far-reaching ecological consequences. Programs to control invaders are common but gauging the effectiveness of such programs using carefully controlled, large-scale field experiments is rare, especially at higher trophic levels. Experimental manipulations coupled with long-term demographic monitoring can reveal the mechanistic underpinnings of interspecific competition among apex predators and suggest mitigation options for invasive species. We used a large-scale before-after control-impact removal experiment to investigate the effects of an invasive competitor, the barred owl (Strix varia), on the population dynamics of an iconic old-forest native species, the northern spotted owl …

Social And Ecological Correlates Of Avian Infection By Haemosporidian Blood Parasites, Ian R. Hoppe

School of Natural Resources: Dissertations, Theses, and Student Research

Haemosporidian parasites are a significant source of morbidity and mortality for birds. There is growing recognition of the negative consequences of haemosporidian infections for wild birds at individual and population levels. Avian haemosporidians are geographically widespread, have been detected from a phylogenetically diverse array of hosts, and have been the focus of extensive research due to their impacts on birds and their similarity to vector-borne diseases of humans. However, factors influencing haemosporidian transmission, especially transmission between species, are poorly understood. To better understand these influences, we compared prevalence and diversity of haemosporidian blood parasite infections among species in a behaviorally …

Nicarbazin As An Oral Contraceptive In Eared Doves, Lourdes Olivera, Silvia Pereyra, Georgget Banchero, Guillermo Tellechea, Jorge Sawchik, Michael L. Avery, Ethel Rodríguez

United States Department of Agriculture Wildlife Services: Staff Publications

Eared doves (Zenaida auriculata) are responsible for substantial losses in cereal and oil crops as well as in dairy and feedlot production in the southern cone of South America. Various strategies have been shown to be effective in reducing damage at the farm scale, but in some scenarios, it is necessary to also incorporate population control methods due to excessive bird population size. An alternative approach to reduce pest bird populations is the use of contraceptive methods, minimizing the impact on the environment and non-target populations. Nicarbazin is registered in the United States as a contraceptive for Branta …

Avian Influenza A Virus Susceptibility, Infection, Transmission, And Antibody Kinetics In European Starlings, Jeremy W. Ellis, J. Jeffrey Root, Loredana M. Mccurdy, Kevin T. Bentler, Nicole L. Barrett, Kaci K. Vandalen, Katherine L. Dirsmith, Susan A. Shriner

United States Department of Agriculture Wildlife Services: Staff Publications

Avian influenza A viruses (IAVs) pose risks to public, agricultural, and wildlife health. Bridge hosts are spillover hosts that share habitat with both maintenance hosts (e.g., mallards) and target hosts (e.g., poultry). We conducted a comprehensive assessment of European starlings (Sturnus vulgaris), a common visitor to both urban and agricultural environments, to assess whether this species might act as a potential maintenance or bridge host for IAVs. First, we experimentally inoculated starlings with a wild bird IAV to investigate susceptibility and replication kinetics. Next, we evaluated whether IAV might spill over to starlings from sharing resources with a …

Mesopredator Frugivory Has No Effect On Seed Viability And Emergence Under Experimental Conditions, John P. Draper, Trisha B. Atwood, Noelle G. Beckman, Karin M. Kettenring, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Members of the order Carnivora are a unique and important seed disperser who consume and deposit undamaged seeds while providing regular long-distance seed dispersal opportunities. Some members of Carnivora, such as coyotes (Canis latrans), are undergoing range expansions which may help the plant species they consume colonize new locations or replace dispersal services provided by recently extirpated species. In this study, we evaluated aspects of the seed dispersal effectiveness of coyotes and gut passage time to determine the potential dispersal distances for three commonly consumed and commonly occurring plant species (Amelanchier alnifolia, Celtis ehrenbergiana, and Juniperus osteosperma). We also investigated …

Climate Adaptation And Water Conservation Decision-Making In Paso Robles, California Vineyards, Christopher R. Klier

Master's Theses

This paper examines vineyard perceptions and adoption of climate change adaptation and water conservation measures in the Paso Robles American Viticultural Area (AVA). A survey was distributed to all 220 vineyards and vineyard management companies that operate in the AVA, with a 53.64% response rate. The objective of the survey was to determine vineyard manager and owner attitudes towards climate change and adaptation, as well as their perceptions of how these threats would impact their operation. A second objective was to document the current level of water conservation and climate adaptation while identifying the barriers and opportunities for further adoption …

Right Side Up: Payment For Ecosystem Services On Privately Owned Grasslands In Nebraska, Kyle Martens

School of Natural Resources: Dissertations, Theses, and Student Research

Grasslands are an important ecological and economic resource in the United States. As part of a natural system, these landscapes can provide income for ranching operations and employment in rural communities; habitat for grassland plants, animals, and migratory species; and offer other services not always readily observed such as improved soil health, clean water, and carbon sequestration. Despite the overarching benefits, the conversion of grasslands to other uses remains widespread throughout much of the remaining Great Plains ecosystem.

Shifting from livestock ranching to another land use often reflects a tipping point. This occurs when the alternative land use is perceived …

Downscaling Of Far-Red Solar-Induced Chlorophyll Fluorescence Of Different Crops From Canopy To Leaf Level Using A Diurnal Data Set Acquired By The Airborne Imaging Spectrometer Hyplant, Bastian Siegmann, Maria Pilar Cendrero-Mateo, Sergio Cogliati, Alexander Damm, John Gamon, David Herrera, Christopehr Jedmowski, Laura Verena Junker-Frohn, Thorsten Kraska, Onno Muller, Patrick Rademske, Christiaan Van Der Tol, Juan Quiros-Vargas, Peiqi Yang, Uwe Rascher

School of Natural Resources: Faculty Publications

Remote sensing-based measurements of solar-induced chlorophyll fluorescence (SIF) are useful for assessing plant functioning at different spatial and temporal scales. SIF is the most direct measure of photosynthesis and is therefore considered important to advance capacity for the monitoring of gross primary production (GPP) while it has also been suggested that its yield facilitates the early detection of vegetation stress. However, due to the influence of different confounding effects, the apparent SIF signal measured at canopy level differs from the fluorescence emitted at leaf level, which makes its physiological interpretation challenging. One of these effects is the scattering of SIF …

The Future Of Wildlife Conservation Funding: What Options Do U.S. College Students Support?, Lincoln R. Larson, Markus Nils Peterson, Richard Von Furstenberg, Victoria R. Vayer, Kangjae Jerry Lee, Daniel Y. Choi, Kathryn Stevenson, Adam A. Ahlers, Christine Anhalt-Depies, Taniya Bethke, Jeremy T. Bruskotter, Christopher J. Chizinski, Brian Clark, Ashley A. Dayer, Kelly Heber Dunning, Benjamin Ghasemi, Larry Gigliotti, Alan Graefe, Kris Irwin, Samuel J. Keith, Matt Kelly, Gerard Kyle, Elizabeth Metcalf, Wayde Morse, Mark D. Needham, Neelam C. Poudyal, Michael Quartuch, Shari Rodriguez, Chelsie Romulo, Ryan L. Sharp, William Siemer, Matthew T. Springer, Brett Stayton, Richard Stedman, Taylor Stein, Timothy R. Van Deelen, Jason Whiting, Richelle L. Winkler, Kyle Maurice Woosnam

School of Natural Resources: Faculty Publications

Insufficient funding is a major impediment to conservation efforts around the world. In the United States, a decline in hunting participation threatens sustainability of the “user-pay, public benefit” model that has supported wildlife conservation for nearly 100 years, forcing wildlife management agencies to contemplate alternative funding strategies. We investigated support for potential funding options among diverse college students, a rapidly expanding and politically active voting bloc with a potentially powerful influence on the future of conservation. From 2018 to 2020, we surveyed 17,203 undergraduate students at public universities across 22 states. Students preferred innovative approaches to conservation funding, with 72% …

Performance Evaluation And Comparison Of Satellite-Derived Rainfall Datasets Over The Ziway Lake Basin, Ethiopia, Aster Tesfaye Hordofa, Olkeba Tolessa Leta, Tena Alamirew, Nafyad Serre Kawo, Abebe Demissie Chukalla

School of Natural Resources: Faculty Publications

Consistent time series rainfall datasets are important in performing climate trend analyses and agro-hydrological modeling. However, temporally consistent ground-based and long-term observed rainfall data are usually lacking for such analyses, especially in mountainous and developing countries. In the absence of such data, satellite-derived rainfall products, such as the Climate Hazard Infrared Precipitations with Stations (CHIRPS) and Global Precipitation Measurement Integrated Multi-SatellitE Retrieval (GPM-IMERG) can be used. However, as their performance varies from region to region, it is of interest to evaluate the accuracy of satellite-derived rainfall products at the basin scale using ground-based observations. In this study, we evaluated and …

Distilling Professional Opinion To Gauge Vulnerability Of Guam Avifauna To Brown Treesnake Predation, Robert M. Mcelderry, Eben H. Paxton, Andre V. Nguyen, Shane R. Siers

United States Department of Agriculture Wildlife Services: Staff Publications

The avifauna of Guam was devastated by the introduction of the Brown Treesnake, and the restoration of native birds would need to address the problem with eradication or suppression of BTS. With eradication of the snake unlikely in the near term, and suppression capabilities limited to specific finite areas, key information for reintroductions is how low BTS abundance will likely need to be for each bird species to be re-established based on their vulnerability to BTS predation. Here, we estimate vulnerability, which can no longer be measured directly, so biologists who are familiar with one or more of seven Guam …

Mapping Heat Vulnerability Index Based On Different Urbanization Levels In Nebraska, Usa, Babak J. Fard, Rezaul Mahmood, Michael Hayes, Clinton M. Rowe, Azar M Abadi, Martha Shulski, Sharon Medcalf, Rachel Lookadoo, Jesse E. Bell

School of Natural Resources: Faculty Publications

Despite similar incidence rates, Heat Vulnerability Index (HVI) in rural areas is under- studied in comparison to urban areas. • The environmental vulnerability variables in rural areas are dissimilar to urban areas, so we applied different variables to calculate them. • We found different organization of socioeconomic variables in calculated HVIs, suggesting separate heat strategies for urbanization levels.

Heatwaves cause excess mortality and physiological impacts on humans throughout the world, and climate change will intensify and increase the frequency of heat events. Many adaptation and mitigation studies use spatial distribution of highly vulnerable local populations to inform heat reduction and …

Diverse University Students Across The United States Reveal Promising Pathways To Hunter Recruitment And Retention, Victoria R. Vayer, Lincoln R. Larson, M. Nils Peterson, Kangjae Jerry Lee, Richard Von Furstenberg, Daniel Y. Choi, Kathryn Stevenson, Adam A. Ahlers, Christine Anhalt-Depies, Taniya Bethke, Jeremy Bruskotter, Christopher J. Chizinski, Brian Clark, Ashley A. Dayer, Benjamin Ghasemi, Larry Gigliotti, Alan Graefe, Kris Irwin, Samuel J. Keith, Matt Kelly, Gerard Kyle, Elizabeth Metcalf, Wayde Morse, Mark D. Needham, Neelam Poudyal, Michael Quartuch, Shari Rodriguez, Chelsie Romulo, Ryan L. Sharp, William Siemer, Matt Springer, Richard Stedman, Taylor Stein, Tim Van Deelen, Jason Whiting, Richelle L. Winkler, Kyle Maurice Woosnam

School of Natural Resources: Faculty Publications

Declining participation in hunting, especially among young adult hunters, affects the ability of state and federal agencies to achieve goals for wildlife management and decreases revenue for conservation. For wildlife agencies hoping to engage diverse audiences in hunter recruitment, retention, and reactivation (R3) efforts, university settings provide unique advantages: they contain millions of young adults who are developmentally primed to explore new activities, and they cultivate a social atmosphere where new identities can flourish. From 2018 to 2020, we surveyed 17,203 undergraduate students at public universities across 22 states in the United States to explore R3 potential on college campuses …

Droughtscape, Summer 2021, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

DroughtScape, Summer 2021

Soil Morphology And Carbon Stocks Of Deflation Basin Wetlands In Eastern Nebraska, Usa, Aubrey Grace Kemper

School of Natural Resources: Dissertations, Theses, and Student Research

Wetlands contribute important ecosystem services such as water filtration and storage, wildlife habitat, and carbon sequestration. The objective of this study is to compare the soil morphology and the carbon and nitrogen stocks between the upland, basin edge, and basin floor in playa wetlands of eastern Nebraska. This work was conducted in three deflation basin wetlands in the Todd Valley, a loess-mantled, former course of the Platte River, in eastern Nebraska. Soil morphological descriptions were evaluated to two meters’ depth using cores collected along three transects from the upland to the basin floor in three basins, carbon and nitrogen stocks …

Understanding And Contextualizing Foraging Among Recreational Opportunities In The North Central United States, Iris I. Mcfarlin

School of Natural Resources: Dissertations, Theses, and Student Research

Over the past few decades, there has been a resurgence in popularity and recognition of foraging for wild products and foods. Despite the cultural importance and ubiquity of foraging, there have been relatively few scientific investigations (as compared to other consumptive outdoor activities such as hunting and fishing) of the social factors influencing foraging behavior, landscape preferences, and the types of materials foraged in the United States. As such, there is a fundamental need to understand more about the practice and about those who participate. We conducted two surveys to gather information on foragers’ motivations and demographic characteristics and to …

Range-Wide Declines Of Northern Spotted Owl Populations In The Pacific Northwest: A Meta-Analysis, Alan B. Franklin, Katie M. Dugger, Damon B. Lesmeister, Raymond J. Davis, J. David Wiens, Gary C. White, James D. Nichols, James E. Hines, Charles B. Yackulic, Carl J. Schwarz, Steven H. Ackers, L. Steven Andrews, Larissa L. Bailey, Robin Bown, Jesse Burgher, Kenneth P. Burnham, Peter C. Carlson, Tara Chestnut, Mary M. Conner, Krista E. Dilione, Eric D. Forsman, Elizabeth M. Glenn, Scott A. Gremel, Keith A. Hamm, Dale R. Herter, J. Mark Higley, Rob B. Horn, Julianna M. Jenkins, William L. Kendall, David W. Lamphear, Christopher Mccafferty, Trent L. Mcdonald, Janice A. Reid, Jeremy T. Rockweit, David C. Simon, Stan G. Sovern, James K. Swingle, Heather Wise

United States Department of Agriculture Wildlife Services: Staff Publications

The northern spotted owl (Strix occidentalis caurina) inhabits older coniferous forests in the Pacific Northwest and has been at the center of forest management issues in this region. The immediate threats to this federally listed species include habitat loss and competition with barred owls (Strix varia), which invaded from eastern North America. We conducted a prospective meta-analysis to assess population trends and factors affecting those trends in northern spotted owls using 26 years of survey and capture-recapture data from 11 study areas across the owls' geographic range to analyze demographic traits, rates of population change, and occupancy parameters for spotted …

Determination Of Freedom-From-Rabies For Small Indian Mongoose Populations In The United States Virgin Islands, 2019–2020, A. Springer Browne, Hannah M. Cranford, Clint N. Morgan, James A. Ellison, Are Berentsen, Nicholas Wiese, Alexandra Medley, John Rossow, Leanne Jankelunas, Alan S. Mckinley, Claudia D. Lombard, Nicole F. Angeli, Thomas Kelley, Jennifer Valiulus, Bethany Bradford, Valicia J. Burke-France, Cosme J. Harrison, Irene Guendel, Marissa Taylor, Gerard L. Blanchard, Jeffrey B. Doty, David J. Worthington, David Horner, Keith R. Garcia, Joseph Roth, Brett R. Ellis, Kristine M. Bisgard, Ryan Wallace, Esther M. Ellis

United States Department of Agriculture Wildlife Services: Staff Publications

Mongooses, a nonnative species, are a known reservoir of rabies virus in the Caribbean region. A cross-sectional study of mongooses at 41 field sites on the US Virgin Islands of St. Croix, St. John, and St. Thomas captured 312 mongooses (32% capture rate). We determined the absence of rabies virus by antigen testing and rabies virus exposure by antibody testing in mongoose populations on all three islands. USVI is the first Caribbean state to determine freedom-from-rabies for its mongoose populations with a scientifically-led robust cross-sectional study. Ongoing surveillance activities will determine if other domestic and wildlife populations in USVI are …

Testing A Bite-Shortened Hook To Minimize Fish Handling In A Recreational Fishery, Holden E. Harris, Brian K. Whalen, Andrew G. Gude, Michael S. Allen

United States Department of Agriculture Wildlife Services: Staff Publications

Discard mortality can make fishing unsustainable, even in catch-and-release or highly regulated fisheries. However, fishing practices and gears that minimize hook injury, handling, and air exposure can considerably improve fitness and survival in released fish. This study tested whether modified hooks could allow anglers to successfully land and then release fish in the water and without handling. Standard, barbless, and bite-shortened hooks were used to catch Spotted Seatrout Cynoscion nebulosus (n > 75 per hook type), and logistic models were used to assess the differences in landing success and hook self-release success by hook type and categorical fish size. Average landing …

Landscape Of Stress: Tree Mortality Influences Physiological Stress And Survival In A Native Mesocarnivore, Jennifer R. Kordosky, Eric M. Gese, Craig M. Thompson, Patricia A. Terletzky, Lorin A. Neuman-Lee, Jon D. Schneiderman, Kathryn L. Purcell, Susannah S. French

United States Department of Agriculture Wildlife Services: Staff Publications

Climate change and anthropogenic modifications to the landscape can have both positive and negative effects on an animal. Linking landscape change to physiological stress and fitness of an animal is a fundamental tenet to be examined in applied ecology. Cortisol is a glucocorticoid hormone that can be used to indicate an animal’s physiological stress response. In the Sierra Nevada Mountains of California, fishers (Pekania pennanti) are a threatened mesocarnivore that have been subjected to rapid landscape changes due to anthropogenic modifications and tree mortality related to a 4-year drought. We measured cortisol concentrations in the hair of 64 …

Risks Of Introduction And Economic Consequences Associated With African Swine Fever, Classical Swine Fever And Foot-And-Mouth Disease: A Review Of The Literature, Vienna Brown, Ryan S. Miller, Sophie C. Mckee, Karina H. Ernst, Nicole M. Didero, Rachel M. Maison, Meredith J. Grady, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

African swine fever (ASF), classical swine fever (CSF) and foot-and-mouth disease (FMD) are considered to be three of the most detrimental animal diseases and are currently foreign to the U.S. Emerging and re-emerging pathogens can have tremendous impacts in terms of livestock morbidity and mortality events, production losses, forced trade restrictions, and costs associated with treatment and control. The United States is the world's top producer of beef for domestic and export use and the world's third-largest producer and consumer of pork and pork products; it has also recently been either the world's largest or second largest exporter of pork …