Zoology Commons^™

Expanding Cwd Disease Surveillance Options Using Environmental Contamination At Deer Signposts, Miranda Hsiang-Ning Jacobson Huang

United States Department of Agriculture Wildlife Services: Staff Publications

1. Environmental surveillance can allow early detection of diseases, which increases management options and can improve disease trajectories. Chronic wasting disease (CWD) in cervids is a significant prion disease that has been spreading across North America since the 1960s, leading to cervid population declines and concern from hunters and state wildlife agencies. White-tailed deer have a unique breeding season behavior called scraping, where they deposit urine and saliva at shared sites. Since both these fluids can contain CWD prions, scrape sites have the potential to serve as sentinel sites for environmental surveillance of CWD.

2. To examine this potential, we …

Taphonomic Signatures Of Early Scavenging By Black And Turkey Vultures, Marian L. Wahl, Grant N. Burcham, Amanda M. Herbert, Lee A. Humberg, Patrick A. Zollner, Landon R. Jones, Brandon M. Quinby, Bryan M. Kluever

United States Department of Agriculture Wildlife Services: Staff Publications

Scavenging is critical for nutrient cycling and maintenance of healthy ecosystems. While there is substantial research into the identification of taphonomic signatures from facultative mammalian scavengers, early stage scavenging signatures by vultures remain unknown. Further, some vulture species are opportunistic predators, highlighting the need to define signatures observed in the course of normal scavenging behavior. We placed stillborn neonatal calves in an unoccupied pasture and used motion-trigger camera traps to quantify scavenging effort, then conducted necropsies to evaluate the effect of black vulture (Coragyps atratus) and turkey vulture (Cathartes aura) scavenging effort on carcass consumption. We …

Relief Displacement Of Airborne Objects, Esteban Fernández-Juricic, Joe Crumpton, Morgan B. Pfeiffer, Sathishkummar Saiappan, Jared A. Elmore, Landon R. Jones, B. Santhana Krishnan, Raymond B. Iglay, Bradley F. Blackwell

United States Department of Agriculture Wildlife Services: Staff Publications

The increasing availability of unoccupied aircraft systems (UAS, also referred to as drones) has led to their use in taking vertical aerial photographs at relatively small spatial scales. These photographs can be used to measure the distances between objects appearing in the photographs. However, relief displacement can cause an object above or below ground level to appear at a point in a vertical aerial photograph that is not directly in-line with the object’s actual location, causing a measurement error. A UAS was used in this study as a photographed airborne object because its location and altitude could be controlled. We …

Reemergence Of A Big Brown Bat Lyssavirus Rabies Variant In Striped Skunks In Flagstaff, Arizona, Usa, 2021–2023, Amy T. Gilbert, Lolita I. Van Pelt, Lias A. Hastings, Crystal M. Gigante, Lillian A. Orciari, Sabrina Kelley, Kathryn Fitzpatrick, René Edgar Condori, Yu Li, Scott Brunt, April Davis, Matthew W. Hopken, Clara C. P. Mankowski, Ryan M. Wallace, Charles E. Rupprecht, Richard B. Chipman, David L. Bergman

United States Department of Agriculture Wildlife Services: Staff Publications

Background

Throughout the Americas, Lyssavirus rabies (RV) perpetuates as multiple variants among bat and mesocarnivore species. Interspecific RV spillover occurs on occasion, but clusters and viral host shifts are rare. The spillover and host shift of a big brown bat (Eptesicus fuscus) RV variant Ef-W1 into mesocarnivores was reported previously on several occasions during 2001–2009 in Flagstaff, Arizona, USA, and controlled through rabies vaccination of target wildlife. During autumn 2021, a new cluster of Ef-W1 RV cases infecting striped skunks (Mephitis mephitis) was detected from United States Department of Agriculture enhanced rabies surveillance in Flagstaff. The …

Population Response Of Eastern Wild Turkey To Removal Of Wild Pigs, Matthew T. Mcdonough, Stephen J. Zenas, Robert A. Gitzen, Mark D. Smith, Kurt C. Vercauteren, Stephen S. Ditchkoff

United States Department of Agriculture Wildlife Services: Staff Publications

There is insufficient understanding of interspecific interactions with the eastern wild turkey (Meleagris gallopavo silvestris) and wild pigs (Sus scrofa). Wild pigs compete with wild turkeys and predate nests and adults; however, population‐level effects on wild turkeys are not clear. Using cameras, we assessed responses of wild turkey populations to wild pig removal in central Alabama, USA, from 2018–2021. We compared wild turkey relative abundance and occupancy on 3 large‐scale pigremoval treatment sites (3,407–5,531 ha) relative to a control site (2,510 ha) during 1 pre‐treatment year and 2 posttreatment years, with analyses including a covariate expressing the cumulative …

Genomic Characterization Of Highly Pathogenic H5 Avian Influenza Viruses From Alaska During 2022 Provides Evidence For Genotype-Specific Trends Of Spatiotemporal And Interspecies Dissemination, Christina A. Ahlstrom, Mia Kim Torchetti, Julianna Lenoch, Kimberlee Beckmen, Megan Boldenow, Evan J. Buck, Bryan Daniels, Krista Dilione, Robert Gerlach, Kristina Lantz, Angela Matz, Rebecca L. Poulson, Laura C. Scott, Gay Sheffield, David Sinnett, David E. Stallknecht, Raphaela Stimmelmayr, Eric Taylor, Alison R. Williams, Andrew M. Ramey

United States Department of Agriculture Wildlife Services: Staff Publications

The ongoing panzootic of highly pathogenic H5 clade 2.3.4.4b avian influenza (HPAI) spread to North America in late 2021, with detections of HPAI viruses in Alaska beginning in April 2022. HPAI viruses have since spread across the state, affecting many species of wild birds as well as domestic poultry and wild mammals. To better understand the dissemination of HPAI viruses spatiotemporally and among hosts in Alaska and adjacent regions, we compared the genomes of 177 confirmed HPAI viruses detected in Alaska during April–December 2022. Results suggest multiple viral introductions into Alaska between November 2021 and August or September 2022, as …

Wildlife Monitoring With Drones: A Survey Of End Users, Raymond B. Iglay, Landon R. Jones, Jared E. Elmore, Kristine O. Evans, Sathish Samiappan, Morgan B. Pfeiffer, Brad F. Blackwell

United States Department of Agriculture Wildlife Services: Staff Publications

Rapid advancements in technology often yield research inquiry into novel applications and drone (i.e., unoccupied aircraft systems or UAS) applications in wildlife management are no exception. We questioned the time lag between drone‐related research and end‐user assessments. We implemented an online, cross‐sectional survey of wildlife professionals to better understand current drone use and benefits or concerns, complemented by a review of contemporary peer‐reviewed and gray literature. We found little disparity between scientific inquiry and end‐user experiences (i.e., similar trends among concerns in published literature and survey results). Exploring new (i.e., advancements in computer vision) and refining original drone applications (i.e., …

Comparing Efficiencies Of Population Control Methods For Responding To Introductions Of Transboundary Animal Diseases In Wild Pigs, Nathan P. Snow, Benjamin Smith, Michael J. Lavelle, Michael P. Glow, Kayleigh Chalkowski, Bruce R. Leland, Sarah Sherburne, Justin W. Fischer, Keely J. Kohen, Seth M. Cook, Hatton Smith, Kurt C. Vercauteren, Ryan S. Miller, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Introductions of transboundary animal diseases (TADs) into free-ranging wildlife can be difficult to control and devastating for domestic livestock trade. Combating a new TAD introduction in wildlife with an emergency response requires quickly limiting spread of the disease by intensely removing wild animals within a contiguous area. In the case of African swine fever virus (ASFv) in wild pigs (Sus scrofa), which has been spreading in many regions of the world, there is little information on the time- and cost-efficiency of methods for intensively and consistently culling wild pigs and recovering carcasses in an emergency response scenario. We compared the …

Temporal And Spatial Influences On Fawn Summer Survival In Pronghorn Populations: Management Implications From Noninvasive Monitoring, Cole A. Bleke, Eric M. Gese, Juan J. Villalba, Shane B. Roberts, Susannah S. French

United States Department of Agriculture Wildlife Services: Staff Publications

Monitoring vital rates allowsmanagers to estimate trends in growth rates of ungulate populations. However, connecting the influence of nutrition on ungulate demography is challenging. Noninvasive sampling offers a low-cost, low-effort alternative for measuring nutritional indices, allowing for an increased understanding of the mechanistic relationships between environmental factors, nutrition, and specific population vital rates. We examined the temporal influence of intrinsic and extrinsic factors on pronghorn (Antilocapra americana) fawn recruitment. We collected fresh fecal samples from adult female pronghorn in five subpopulations spanning three sampling periods associated with critical maternal life-history stages (late gestation, early lactation, breeding season) for …

Susceptibilities And Viral Shedding Of Peridomestic Wildlife Infected With Clade 2.3.4.4b Highly Pathogenic Avian Influenza Virus (H5n1), J. Jeffrey Root, Stephanie M. Porter, Julianna B. Lenoch, Jeremy W. Ellis, Angela M. Bosco-Lauth

United States Department of Agriculture Wildlife Services: Staff Publications

We tested the ability of six peridomestic wildlife species to replicate a highly pathogenic (HP) clade 2.3.4.4b AIV (H5N1) isolated in the United States during 2022. All tested species replicated and shed virus, at least to some degree. Of the six species evaluated (house sparrows (Passer domesticus), European starlings (Sturnus vulgaris), feral pigeons (Columba livia), striped skunks (Mephitis mephitis), Virginia opossums (Didelphis virginiana), and cottontails (Sylvilagus sp.)), striped skunks and Virginia opossums shed the highest viral titers of 106.3 PFU/mL and 105.0 PFU/mL, respectively. Overall, the results of this …

Chronic Wasting Disease Effects On A Breeding Season Behavior In White-Tailed Deer (Odocoileus Virginianus), Miranda Hsiang-Ning Jacobson Huang, Stephen Demarais, Bronson K. Strickland, Allan Houston, Alejandro Banda, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife disease outbreaks can lead to population declines, which are usually attributed to increased direct or indirect mortality. Alternatively, behavior associated with sickness can lead to social isolation, potentially decreasing fitness of affected individuals. A useful case study to examine this dynamic is chronic wasting disease (CWD), a neurological disease of cervids, known to affect behavior and movement. In this study, we monitored scraping, a White-tailed Deer (Odocoileus virginianus; WTD) breeding season behavior, in an area of high CWD prevalence to determine if this reproductive behavior is affected by CWD. At 107 scrape sites, we detected 3,063 scrape interactions and …

Trichinella Murrelli Identified In Red Foxes (Vulpes Vulpes) In Pennsylvania, Usa, Jitender Dubey, Peter C. Thompson, Larissa S. De Araujo, Aditya Gupta, Sasha Kay, Oliver C. H. Kwok, Jaquin Battle, Kyle R. Van Why, Justin D. Brown, Benjamin Rosenthal

United States Department of Agriculture Wildlife Services: Staff Publications

Trichinella infections have been eliminated from pork where pigs are raised in biosecure facilities, but wildlife infections persist. Trichinella murrelli is the primary zoonotic species in wild carnivores in the United States, having been identified in several species of omnivores and carnivores. Here, we document its occurrence in seven of 21 (33.3%) red foxes (Vulpes vulpes) from six counties in Pennsylvania. Encysted Trichinella juveniles were detected in muscle squashes (< 5 g samples) of all seven foxes, and in histological sections of the tongue and limb muscle of three. Juveniles from muscle squashes were pooled and tested in a multiplex PCR capable of differentiating all Trichinella species native to the USA; all samples contained only T. murrelli. This is the first identification of T. murrelli in red foxes from Pennsylvania, …

Efficacy Of Gonacon Fertility Control Against Prairie Dogs And Potential For Uses On Other Rodent Species, Aaron B. Shiels, Emily W. Ruell, Jason E. Bruemmer

United States Department of Agriculture Wildlife Services: Staff Publications

Use of a contraceptive (i.e., fertility control) is attractive for rodent management where lethal control is unwanted. Although population reduction is generally unachievable with small-scale, short-term contraceptive use, reduced juvenile recruitment is achievable. The injectable immunocontraceptive vaccine GonaCon (active ingredient: gonadotropin releasing hormone [GnRH]) was registered in 2022 by the United States Environmental Protection Agency (EPA) for controlling fertility of female prairie dogs (Cynomys, a type of ground squirrel) in urban/suburban settings. Here we: 1) describe past research, including a replicated field study in Colorado (GonaCon treatment vs. control sites) testing efficacy of GonaCon in prairie dogs, which …

The Influence Of Social And Spatial Processes On The Epidemiology Of Environmentally Transmitted Pathogens In Wildlife: Implications For Management, Aakash Pandey, Chris Wojan, Abigail Feuka, Meggan E. Craft, Kezia Manlove, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Social and spatial structures of host populations play important roles in pathogen transmission. For environmentally transmitted pathogens, the host space use interacts with both the host social structure and the pathogen’s environmental persistence (which determines the timelag across which two hosts can transmit). Together, these factors shape the epidemiological dynamics of environmentally transmitted pathogens. While the importance of both social and spatial structures and environmental pathogen persistence has long been recognized in epidemiology, they are often considered separately. A better understanding of how these factors interact to determine disease dynamics is required for developing robust surveillance and management strategies. Here, …

Surveillance Of Highly Pathogenic Avian Influenza Virus In Wild Canids From Pennsylvania, Usa, Kevin D. Niedringhaus, Taylor C. Chan, Ashley Mcdowell, Lauren Mxwell, Madison Stevens, Lane Potts, Erica Miller, Eman Anis, Kyle Van Why, Thomas Keller, David Stallknecht, Rebecca L. Poulson, Kaitlyn Bahrs, Justin D. Brown

United States Department of Agriculture Wildlife Services: Staff Publications

The avian influenza virus is a global pathogen with significant health and economic implications. While primarily a pathogen of wild and domestic birds, recent outbreaks of the H5N1 highly pathogenic avian influenza virus (HPAIV) clade 2.3.4.4b have caused mortality in a wide variety of mammals, including members of the Canidae family, on multiple continents. Despite sporadic mortality events globally, the epidemiology and pathobiology of H5N1 HPAIV in wild canids remains poorly defined. During 2022–2024, 41 wild canid carcasses (diagnostic cases), including 23 red foxes and 18 gray foxes, were tested for the influenza A virus (IAV) via PCR, with five …

Rabies, Amy T. Gilbert, Christine Ellis

United States Department of Agriculture Wildlife Services: Staff Publications

Illustrated fact sheet on rabies.

An Effective Method For Long-Term Control Of American Bullfrogs Syntopic With Special-Status Native Amphibians In California, Usa, Jeff A. Alvarez, Jeffery T. Wilcox

Human–Wildlife Interactions

American bullfrogs (Lithobates catesbeianus) are invasive in western North America and are well established in California, USA, where they are widespread. This invasive species has been implicated in the decrease of native amphibian populations and is believed to have contributed to the decline of threatened and endangered amphibians regionally. We utilized air rifles, tin alloy pellets, and 2 shooters to systematically control L. catesbeianus in both lentic and lotic habitat types within 2 counties in California. We visited sites monthly (April through November) for approximately 8 and 14 years to lethally target and remove L. catesbeianus …

Quantifying Wild Pig Disturbance In Pastures And Wetlands Using Unmanned Aerial Vehicle-Derived Imagery, Wesley M. Anderson, Bethany Wight, Raoul K. Boughton

Human–Wildlife Interactions

The use of unmanned aerial vehicles (UAVs) for agricultural and environmental research has increased markedly in recent years, and a key application has been to conduct damage assessments. Invasive wild pigs (Sus scrofa) cause both agricultural and environmental damage, and past studies have utilized UAVs to quantify this damage. Each methodology has advantages, but they also have drawbacks such as high rates of damage omission or reliance upon a near-infrared camera, which may be prohibitively expensive for some land managers and scientists. Our objective was to develop a methodology that could be easily implemented to conduct wild pig …

Is Mitigation Translocation An Effective Method For Reducing Laysan Albatross–Military Aircraft Collisions?, Brian E. Washburn, Katherine D. Rubiano, William P. Bukoski

Human–Wildlife Interactions

Wildlife–aircraft collisions (wildlife strikes) pose a serious risk to civil and military aircraft. Each year, Laysan albatrosses (Phoebastria immutabilis) attempt to establish a breeding colony on the airfield at the U.S. Navy’s Pacific Missile Range Facility (PMRF) located on the island of Kaua‘i, Hawai‘i, USA, resulting in a hazard to safe military aircraft operations at this facility. A long-term management program, with an emphasis on mitigation translocation (e.g., live-capture and translocation away from the area) of problematic individuals, has been conducted by the U.S. Department of Agriculture, Wildlife Services. However, the efficacy of mitigation translocation as a nonlethal …

Comparing Alternative Developmental Modes: Structure And Gene Expression In The Olfactory System Of Plethodontid Salamanders, Giuseppina S. Lanzilli

Cal Poly Humboldt theses and projects

The olfactory system of extant amphibians changes as the animal transitions from a fully aquatic to a terrestrial lifestyle at metamorphosis. Cellular morphology of the nose and expression patterns of olfactory genes in the nasal cavity have been examined for a variety of frogs and salamanders, but among plethodontid salamanders, molecular data are available only for Plethodon shermani. Using standard histology and micro-CT reconstruction, I investigated the structure of the olfactory organs of larvae, juveniles, and adults of six plethodontid species, with terrestrial, streamside, semiaquatic, and aquatic adults. The overall structure of the olfactory cavity was generally similar across …