Population Biology Commons^™

High Winds And Melting Sea Ice Trigger Landward Movement In A Polar Bear Population Of Concern, Annie Kellner, Todd C. Atwood, David C. Douglas, Stewart W. Breck, Colorado State University - Fort Collins

United States Department of Agriculture Wildlife Services: Staff Publications

Some animal species are responding to climate change by altering the timing of events like mating and migration. Such behavioral plasticity can be adaptive, but it is not always. Polar bears (Ursus maritimus) from the southern Beaufort Sea subpopulation have mostly remained on ice year-round, but as the climate warms and summer sea ice declines, a growing proportion of the subpopulation is summering ashore. The triggers of this novel behavior are not well understood. Our study uses a parametric time-to-event model to test whether biological and/or time-varying environmental variables thought to influence polar bear movement and habitat selection …

Space Use And Movements Of Southeastern Breeding Double-Crested Cormorants (Nannopterum Auritum) In The United States, Leah L.K. Moran, Brian S. Dorr, Katie C. Hanson-Dorr, R. J. Moore, Scott A. Rush

United States Department of Agriculture Wildlife Services: Staff Publications

Abstract: Seasonal movements of Double-crested Cormorants (Nannopterum auritum) have been studied at breeding and wintering sites in the southeastern United States, but little information exists on the movements of these birds within and from their southern breeding sites in lacustrine systems. Since 2001, cormorants have established nesting colonies on islands in Guntersville Reservoir in Alabama, USA. Following the movements of tagged cormorants using satellite telemetry, we found that the mean home range during the 2017 breeding season (May–August) was 41.76 km², with a core use area of 6.36 km². The mean home range used …

Behavior Of Wild Pigs Toward Conspecific Carcasses: Implications For Disease Transmission In A Hot, Semiarid Climate, Samantha Leivers, Tyler Campbell, Michael J. Bodenchuk, John Tomeĉek

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are a prolific, invasive species in the United States of America and act as vectors for many pathogens. An emerging pathogen of concern to the USA is African swine fever (ASF), a deadly viral disease affecting swine that is endemic to Africa and has spread to parts of Europe, Asia, and the Caribbean. ASF affects both wild and domesticated pigs and can be transmitted via several avenues, including interactions between and consumption of dead pigs by their live conspecifics. As wild pigs are considered a serious threat in the transmission of ASF, understanding the …

Deriving Spatially Explicit Direct And Indirect Interaction Networks From Animal Movement Data, Anni Yang, Mark Q. Wilber, Kezia R. Manlove, Ryan S. Miller, Raoul Boughton, James Beasley, Joseph Northrup, Kurt C. Vercauteren, George Wittemyer, Kim Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Quantifying spatiotemporally explicit interactions within animal populations facilitates the understanding of social structure and its relationship with ecological processes. Data from animal tracking technologies (Global Positioning Systems [“GPS”]) can circumvent longstanding challenges in the estimation of spatiotemporally explicit interactions, but the discrete nature and coarse temporal resolution of data mean that ephemeral interactions that occur between consecutive GPS locations go undetected. Here, we developed a method to quantify individual and spatial patterns of interaction using continuous-time movement models (CTMMs) fit to GPS tracking data. We first applied CTMMs to infer the full movement trajectories at an arbitrarily fine temporal scale …

Long Term Changes In Aquaculture Influence Migration, Regional Abundance, And Distribution Of An Avian Species, Paul C. Burr, Brian S. Dorr, Jimmy L. Avery, Garrett M. Street, Bronson K. Strickland

United States Department of Agriculture Wildlife Services: Staff Publications

Agricultural development has been causing changes to the environment and the abundance and distribution of avian species. Agriculture is dynamic with changes in products occurring at large scales over relatively short time periods. The catfish aquaculture industry is one such agriculture industry that has undergone dramatic changes over the last 25 years. The double-crested cormorant (Nannopterum auritum) is a piscivorous bird that has an extensive history with the aquaculture industry of Mississippi due to its depredation of cultured catfish. A large-scale monitoring program began in 1989 to estimate the abundance and location of cormorants at every known roost in the …

Disease Progression And Serological Assay Performance In Heritage Breed Pigs Following Brucella Suis Experimental Challenge As A Model For Naturally Infected Feral Swine, Vienna R. Brown, Ryan S. Miller, Courtney F. Bowden, Timothy J. Smyser, Nicholas A. Ledesma, Aim E. Hartwig, Paul Gordy, Aaron M. Anderson, Stephanie M. Porter, Kate Alexander, Zane Gouker, Tom Gidlewski, Richard A. Bowen, Angela M. Bosco-Lauth

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive feral swine (Sus scrofa) are one of the most important wildlife species for disease surveillance in the United States, serving as a reservoir for various diseases of concern for the health of humans and domestic animals. Brucella suis, the causative agent of swine brucellosis, is one such pathogen carried and transmitted by feral swine. Serology assays are the preferred field diagnostic for B. suis infection, as whole blood can be readily collected and antibodies are highly stable. However, serological assays frequently have lower sensitivity and specificity, and few studies have validated serological assays for B. suis in feral swine. …

Evaluation Of The Effect Of Hydrated Lime On The Scavenging Of Feral Swine (Sus Scrofa) Carcasses And Implications For Managing Carcass-Based Transmission Of African Swine Fever Virus, Courtney F. Bowden, James Grinolds, Gregory Franckowiak, Loma Mccallister, Joe M. Halseth, Matthew Cleland, Travis Guerrant, Michael J. Bodenchuk, Robert Miknis, Michael C. Marlow, Vienna R. Brown

United States Department of Agriculture Wildlife Services: Staff Publications

African swine fever (ASF) is a devastating hemorrhagic disease marked by extensive morbidity and mortality in infected swine. The recent global movement of African swine fever virus (ASFV) in domestic and wild swine (Sus scrofa) populations has initiated preparedness and response planning activities within many ASF-free countries. Within the US, feral swine are of utmost concern because they are susceptible to infection, are wide-spread, and are known to interact with domestic swine populations. African swine fever virus is particularly hardy and can remain viable in contaminated carcasses for weeks to months; therefore, carcass-based transmission plays an important role in the …

H7n9 Influenza A Virus Transmission In A Multispecies Barnyard Model, Angela M. Bosco-Lauth, Anna Rodriguez, Rachel M. Maison, Stephanie M. Porter, J. Jeffrey Root

United States Department of Agriculture Wildlife Services: Staff Publications

Influenza A viruses are a diverse group of pathogens that have been responsible for millions of human and avian deaths throughout history. Here, we illustrate the transmission potential of H7N9 influenza A virus between Coturnix quail (Coturnix sp.), domestic ducks (Anas platyrhynchos domesticus), chickens (Gallus gallus domesticus), and house sparrows (Passer domesticus) co-housed in an artificial barnyard setting. In each of four replicates, individuals from a single species were infected with the virus. Quail shed virus orally and were a source of infection for both chickens and ducks. Infected chickens transmitted the virus to quail but not to ducks or …

Raccoon Rabies Control And Elimination In The Northeastern Usa And Southern Québec, Canada, Amy J. Davis, Marianne Gagnier, Ariane Massé, Kathleen M. Nelson, Jordona D. Kirby, Ryan Wallace, Xiaoyue Ma, Christine Fehlner-Gardiner, Richard B. Chipman, Amy Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

Rabies virus (RABV) is a deadly zoonosis that circulates in wild carnivore populations in North America. Intensive management within the USA and Canada has been conducted to control the spread of the raccoon (Procyon lotor) variant of RABV and work towards elimination. We examined RABV occurrence across the northeastern USA and southeastern Québec, Canada during 2008–2018 using a multi-method, dynamic occupancy model. Using a 10 km× 10 km grid overlaid on the landscape, we examined the probability that a grid cell was occupied with RABV and relationships with management activities (oral rabies vaccination (ORV) and trap-vaccinate-release efforts), habitat, neighbour effects …

Validation Of A Nutria (Myocastor Coypus) Environmental Dna Assay Highlights Considerations For Sampling Methodology, Anna M. Mangan, John A. Kronenberger, Ian H. Plummer

United States Department of Agriculture Wildlife Services: Staff Publications

Nutria (Myocastor coypus) is a semiaquatic rodent species that is invasive across multiple regions within the United States. Here, we evaluated a qPCR assay previously described for use in Japan for application across invasive populations in the United States. We also compared two environmental DNA sampling methodologies for this assay: field filtration of large volumes of water passed through filters versus direct sampling of small volumes of water. We validated assay specificity, generality, and sensitivity, compared assay performance between two independent laboratories, and successfully tested the assay in situ on a known wild population. The filtration method required …

Writing Statistical Methods For Ecologists, Amy J. Davis, Shannon Kay

United States Department of Agriculture Wildlife Services: Staff Publications

The Methods section is a key component of any ecology research publication containing detailed information on how the data were collected and analyzed. However, descriptions of which statistical methods were used and how they were applied can substantially vary and may not provide enough information for the analyses to be reproducible. Computational and statistical programming advances have allowed ecological researchers without a strong statistical or mathematical background to access and use increasingly complex statistical methods. Thus, statistical methods are written by and need to be accessible to researchers across a range of quantitative expertise. Poorly written Methods sections can incorrectly …

Variance In Offspring Sex Ratio And Maternal Allocation In A Highly Invasive Mammal, Sarah M. Chinn, Timothy J. Smyser, James C. Beasley

United States Department of Agriculture Wildlife Services: Staff Publications

Skewed sex ratios at birth are widely reported in wild populations, however, the extent to which parents are able to modulate the sex ratio of offspring to maximize their own fitness remains unclear. This is particularly true for highly polytocous species as maximizing fitness may include trade-offs between sex ratio and the size and number of offspring in litters. In such cases, it may be adaptive for mothers to adjust both the number of offspring per litter and offspring sex to maximize individual fitness. Investigating maternal sex allocation in wild pigs (Sus scrofa) under stochastic environmental conditions, we predicted that …

Genomic Analyses Of Gray Fox Lineages Suggest Ancient Divergence And Secondary Contact In The Southern Great Plains, Elizabeth M. Kierepka, Sophie Preckler-Quisquater, Dawn M. Reding, Antoinette Piaggio, Seth P.D. Riley, Benjamin N. Sacks

United States Department of Agriculture Wildlife Services: Staff Publications

The gray fox (Urocyon cinereoargenteus) lineage diverged from all other extant canids at their most basal node and is restricted to the Americas. Previous mitochondrial analysis from coastal populations identified deeply divergent (up to 1 Mya) eastern and western lineages that predate most intraspecific splits in carnivores. We conducted genotyping by sequencing and mitochondrial analysis on gray foxes sampled across North America to determine geographic concordance between nuclear and mitochondrial contact zones and divergence times. We also estimated the admixture within the contact zone between eastern and western gray foxes based on nuclear DNA. Both datasets confirmed that …

The Past, Present, And Future Of Equine Science, Sarah H. White-Springer, Jason E. Bruemmer, Robert J. Coleman

United States Department of Agriculture Wildlife Services: Staff Publications

A core group of 27 equine nutritionists and physiologists joined together in the late 1960s to formally address and enhance the direction of equine research, creating the Equine Nutrition and Physiology Soci- ety. In 2003, that growing society transformed into the Equine Science Society, which now serves as the preeminent, internationally recognized scientific equine organization. In recent years, it has been appre- ciated that equine science encompasses a wide range of focus areas, including exercise science, nutrition, genetics, reproductive physiology, teaching and extension, production and management, and mix of other specialties, qualified as biosciences. Additionally, trainees are highly valued in …

Invasive Frogs Show Persistent Physiological Differences To Elevation And Acclimate To Colder Temperatures, Jack R. Marchetti, Karen H. Beard, Emily E. Virgin, Erin L. Lewis, Steven C. Hess, Kwanho C. Ki, Layne O. Sermersheim, Adriana P. Furtado, Susannah S. French

United States Department of Agriculture Wildlife Services: Staff Publications

The coqui frog (Eleutherodactylus coqui) was introduced to the island of Hawai’i in the 1980s and has spread across much of the island. Concern remains that this frog will continue to expand its range and invade higher elevation habitats where much of the island’s endemic species are found. We determined whether coqui thermal tolerance and physiology change along Hawai’i’s elevational gradients. We measured physiological responses using a short-term experiment to determine baseline tolerance and physiology by elevation, and a long-term experiment to determine the coqui’s ability to acclimate to different temperatures. We collected frogs from low, medium, and …

Perturbations Highlight Importance Of Social History In Parakeet Rank Dynamics, Annemarie Van Der Marel, Xavier Francis, Claire L. O'Connell, Cesar O. Estien, Chelsea Carminito, Virginia Darby Moore, Nickolas Lormand, Bryan M. Kluever, Elizabeth A. Hobson

United States Department of Agriculture Wildlife Services: Staff Publications

Dominance hierarchies can provide many benefits to individuals, such as access to resources or mates, depending on their ranks. In some species, rank can emerge as a product of a group’s history of social interactions. However, it can be difficult to determine whether social history is critical to rank in observation-based studies. Here, we investigated rank dynamics in three captive groups of monk parakeets (Myiopsitta monachus). We used experimental social perturbations to test whether social history shapes rank emergence in these groups. Using targeted removals and reintroductions, we tested whether differently ranked individuals could re-take their ranks in hierarchies after …

Distribution Of The Misfolded Isoform Of The Prion Protein In Peripheral Tissues And Spinal Cord Of Rocky Mountain Elk (Cervus Elaphus Nelsoni) With Naturally Occurring Chronic Wasting Disease, Terry R. Spraker, Thomas Gidlewski, J. G. Powers, T. A. Nichols, M. A. Wild

United States Department of Agriculture Wildlife Services: Staff Publications

Chronic wasting disease (CWD) is an infectious transmissible spongiform encephalopathy of cervids associated with the presence of a misfolded prion protein (PrPCWD). Progression of PrPCWD distribution has been described using immunohistochemistry and histologic changes in a single section of brain stem at the level of the obex resulting in scores from 0 (early) to 10 (terminal) in elk with naturally occurring CWD. Here we describe the spread and distribution of PrPCWD in peripheral tissues and spinal cord in 16 wild and 17 farmed Rocky Mountain elk (Cervus elaphus nelsoni) with naturally occurring CWD and correlate these findings with obex scores. …

Producers’ Perceptions Of Large Carnivores And Nonlethal Methods To Protect Livestock From Depredation: Findings From A Multistate Federal Initiative, Keith M. Carlisle, Hailey E. Ellis, Colorado State University, Alan D. Bright

United States Department of Agriculture Wildlife Services: Staff Publications

We examined livestock producers’ perceptions of wolves, grizzly bears, black bears, and mountain lions, as well as their experiences with using nonlethal methods to protect livestock from depredation. All producers in the study received nonlethal predator management assistance in 2020 from USDA-APHIS-Wildlife Services (“WS”) pursuant to a federally funded initiative focused on the use of nonlethal methods to protect livestock. Such methods included assistance from range riders (i.e., individuals who monitor livestock and carnivores), fladry (i.e., flags hung from rope that serve as a repellent), and other audio/visual deterrents (e.g., Foxlights). The producers did not specifically seek nonlethal assistance from …

Integrating Robotics Into Wildlife Conservation: Testing Improvements To Predator Deterrents Through Movement, Stewart W. Breck, Jeffrey T. Schultz, David Prause, Cameron Krebs, Anthony J. Giordano, Byron Boots

United States Department of Agriculture Wildlife Services: Staff Publications

Background Agricultural and pastoral landscapes can provide important habitat for wildlife conservation, but sharing these landscapes with wildlife can create conflict that is costly and requires managing. Livestock predation is a good example of the challenges involving coexistence with wildlife across shared landscapes. Integrating new technology into agricultural practices could help minimize human-wildlife conflict. In this study, we used concepts from the fields of robotics (i.e., automated movement and adaptiveness) and agricultural practices (i.e., managing livestock risk to predation) to explore how integration of these concepts could aid the development of more effective predator deterrents.

Methods …

Distribution Of Baylisascaris Procyonis In Raccoons (Procyon Lotor) In Florida, Usa, Mark W. Cunningham, Daniel P. Wolf, Katherine A. Sayler, Michael Milleson, Brittany Bankovich, Paul Schueller, Betsy S. Haley, Savannah Stura, Michael J. Yabsley

United States Department of Agriculture Wildlife Services: Staff Publications

Baylisascaris procyonis, or raccoon roundworm, is an intestinal nematode parasite of raccoons (Procyon lotor) that is important to public and wildlife health. Historically, the parasite was uncommon in the southeastern US; however, the range of B. procyonis has expanded to include Florida, US. From 2010 to 2016, we opportunistically sampled 1,030 raccoons statewide. The overall prevalence was 3.7% (95% confidence interval=2.5–4.8%) of sampled individuals, and infection intensity ranged from 1 to 48 (mean±standard deviation 9.9±4.0). We found raccoon roundworm in 9/56 (16%) counties sampled, and the percent positive ranged from 1.1% to 13.3% of specimens collected per …