Population Biology Commons^™

Hawaii As A Microcosm: Advancing The Science And Practice Of Managing Introduced And Invasive Species, Liba Pejchar, Christopher A. Lepczyk, Jean E. Fantle-Lepczyk, Steven C. Hess, M. Tracy Johnson, Christina R. Leopold, Michael Marchetti, Katherine M. Mcclure, Aaron B. Shiels

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive species are a leading driver of global change, with consequences for biodiversity and society. Because of extraordinary rates of endemism, introduction, and extinction, Hawaii offers a rich platform for exploring the cross-disciplinary challenges of managing invasive species in a dynamic world. We highlight key successes and shortcomings to share lessons learned and inspire innovation and action in and beyond the archipelago. We then discuss thematic challenges and opportunities of broad relevance to invaded ecosystems and human communities. Important research needs and possible actions include eradicating mammals from mainland island sanctuaries, assessing hidden threats from poorly known introduced species, harnessing …

Deciphering Interactions Between White-Tailed Deer And Approaching Vehicle, Morgan Pfeiffer, Raymond B. Iglay, Thomas W. Seamans, Bradley F. Blackwell, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Deer-vehicle collisions are a major transportation hazard, but factors affecting deer escape decision-making in response to vehicle approach remain poorly characterized. We made opportunistic observations of deer response to vehicle approach during daylight hours on a restricted- access facility in Ohio, USA (vehicle speeds were ≤64 km/h). We hypothesized that animal proximity to the road, group size, vehicle approach, and ambient conditions would affect perceived risk by white-tailed deer (Odocoileus virginianus) to vehicle approach, as measured by flight-initiation distance (FID). We constructed a priori models for FID, as well as road-crossing behavior. Deer responses were variable and did not demonstrate …

Evaluating Moose Alces Alces Population Response To Infestation Level Of Winter Ticks Dermacentor Albipictus, Daniel D. Ellingwood, Peter J. Pekins, Henry Jones, Anthony R. Musante

United States Department of Agriculture Wildlife Services: Staff Publications

Many wildlife populations are experiencing a variety of environmental pressures due to the direct and indirect consequences of a changing climate. In the northeast, USA, moose Alces alces are declining in large part because of the increasing parasitism by winter tick Dermacentor albipictus, facilitated by high host density and optimal environmental conditions. To test this hypothesis, and better understand the influence of this interaction on the stability of the regional population, we constructed a population viability model using data collected through comprehensive survival and productivity studies in 2002–2005 and 2014–2018 in northern New Hampshire. Years of heavy tick infestation (epizootics) …

Spillover Of Sars-Cov-2 Into Novel Wild Hosts In North America: A Conceptual Model For Perpetuation Of The Pathogen, Alan B. Franklin, Sarah N. Bevins

United States Department of Agriculture Wildlife Services: Staff Publications

There is evidence that the current outbreak of the novel coronavirus SARS-CoV-2, which causes COVID-19, is of animal origin. As with a number of zoonotic pathogens, there is a risk of spillover into novel hosts. Here, we propose a hypothesized conceptual model that illustrates the mechanism whereby the SARS-CoV-2 could spillover from infected humans to naive wildlife hosts in North America. This proposed model is premised on transmission of SARS-CoV-2 from human feces through municipal wastewater treatment plants into the natural aquatic environment where potential wildlife hosts become infected. We use the existing literature on human coronaviruses, including SARS CoV, …

Is Anyone Home? Year Round Site Fidelity Vs. Temporal Territories In Estuarine Blennies, Nicholas Govostes

Honors Theses

Temperate oyster reef blennies use articulated oyster shells as nest sites in warmer months during breeding season but little is known about their site fidelity during non-breeding season. Unlike coral reef blennies that occupy territories year-round, rocky intertidal temperate blenny species display temporal territories and seasonally migrate into breeding shelters. Striped blenny (Chasmodes bosquianus) shelter use was described from November 2019 through March 2020 at Oyster Landing, North Inlet estuary, SC to quantify the proportion of daylight hours when fish were in residence and describe potential relationships between shelter occupancy and neighboring fishes. Replicate PVC shelters were monitored …

Development Of Methods To Track Oyster Movement Under Field Conditions In North Inlet Estuary, South Carolina, Alyssa M. Leclaire

Honors Theses

Eastern oyster (Crassostrea virginica) reefs provide important habitat structure and ecosystem services in saltmarsh tidal creek estuaries. Reef persistence depends on growth of resident individuals and regular recruitment to maintain suitable shell substrate. Boat wakes potentially physically displace oyster clumps. The objective of this research was to develop methods to track oyster clump position and biomass on two natural fringing oyster reefs in North Inlet estuary, South Carolina. Boat traffic (number of boats making wakes per day), oyster clump displacement (cm/d) over time, oyster biomass (g dry tissue), and condition index (biomass/g dry shell weight) were quantified from …

Public Perspectives And Media Reporting Of Wolf Reintroduction In Colorado, Rebecca Niemiec, Richard E.W. Berl, Mireille Gonzalez, Tara Teel, Cassiopeia Camara, Matthew Collins, Jonathan Salerno, Kevin Crooks, Courtney Schultz, Stewart Breck, Dana Hoag

United States Department of Agriculture Wildlife Services: Staff Publications

In the state of Colorado, a citizen ballot initiative to reintroduce gray wolves (Canis lupus) is eliciting polarization and conflict among multiple stakeholder and interest groups. Given this complex social landscape, we examined the social context surrounding wolf reintroduction in Colorado as of 2019. We used an online survey of 734 Coloradans representative in terms of age and gender, and we sampled from different regions across the state, to examine public beliefs and attitudes related to wolf reintroduction and various wolf management options. We also conducted a content analysis of media coverage on potential wolf reintroduction in 10 major daily …

Status Of The Blackstripe (Fundulus Notatus) And Blackspotted (F. Olivaceus) Topminnows In The Ozark Uplands Of Central Missouri, Nathaniel Steffensmeier, Naznin Sultana Remex, Robert Hrabik, David D. Duvernell

Biological Sciences Faculty Research & Creative Works

The topminnow species Fundulus notatus and F. olivaceus have broadly overlapping geographic distributions that extend throughout much of the central and southern United States. In the northern portion of their respective ranges, in Missouri, the regional distributions of the two species coincide largely with recognized ecoregions. In the unglaciated southern half of Missouri, F. olivaceus is distributed throughout Ozark upland habitats while F. notatus is abundant in marginal large river and prairie habitats along the Ozark borders. An exception to this partitioning is the historical report of abundant F. notatus in the Bourbeuse and upper Meramec River drainages within the …

Talking Trash In The Big Apple: Mitigating Bird Strikes Near The North Shore Marine Transfer Station, Stephan J. Beffre, Brian E. Washburn

United States Department of Agriculture Wildlife Services: Staff Publications

Anthropogenic activities that concentrate wildlife near airports increases the risk of wildlife–aircraft collisions. Placing waste management facilities, natural areas, golf courses, and other landscape features near airports have the potential to attract wildlife hazardous to aviation. We conducted a 3-year study (March 2013–February 2016) to determine if the implementation of a Wildlife Hazard Mitigation Program (WHMP) would influence the bird use of a waste transfer station located near LaGuardia Airport, New York City, New York, USA. We conducted wildlife surveys during 3 phases: (1) no mitigation program and no waste transfer station, (2) active mitigation and no waste transfer station, …

Collective Effect Of Landfills And Landscape Composition On Bird–Aircraft Collisions, Morgan Pfeiffer, Bradley F. Blackwell, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Ninety-three percent of all reported bird strikes occur below 1,067 m, which based on the typical approach and departure angles of aircraft is within 8–13 km of an airport. Concomitantly, the Federal Aviation Administration and the International Civil Aviation Organization recommend that any feature that would attract hazardous wildlife to the approach and departure airspace be restricted. Thus, preventing the establishment of wildlife attractants, such as municipal solid waste landfills (MSWLFs) within 8 km or 13 km extents (U.S. and international recommendations, respectively) of airports, has been recommended to mitigate the risk of bird–aircraft collisions (strikes). However, robust evidence linking …

Testing A Key Assumption Of Using Drones As Frightening Devices: Do Birds Perceive Drones As Risky?, Conor C. Egan, Bradley Blackwell, Esteban Fernández-Juricic, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife managers have recently suggested the use of unmanned aircraft systems or drones as nonlethal hazing tools to deter birds from areas of human-wildlife conflict. However, it remains unclear if birds perceive common drone platforms as threatening. Based on field studies assessing behavioral and physiological responses, it is generally assumed that birds perceive less risk from drones than from predators. However, studies controlling for multiple confounding effects have not been conducted. Our goal was to establish the degree to which the perception of risk by birds would vary between common drone platforms relative to a predator model when flown at …

Factors Affecting Bait Site Visitation: Area Of Influence Of Baits, Jacquelyn E. Mcrae, Peter E. Schlichting, Nathan P. Snow, Amy J. Davis, Kurt C. Vercautern, John C. Kilgo, David A. Keiter, James C. Beasley, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

ABSTRACT Baiting is a fundamental strategy for the global management of wild pigs (Sus scrofa); however, little information exists on how anthropogenic bait affects wild pig movements on a landscape. We investigated factors that are important in determining the spatial area of attraction for wild pigs to bait (‘area of influence’ of a bait site) using data from Global Positioning System (GPS) collars and locations of bait sites. We monitored movements of wild pigs in 2 distinct study areas in the United States from February to September 2016 and used locational data using GPS collars to analyze the influence of …

A Rapid Population Assessment Method For Wild Pigs Using Baited Cameras At 3 Study Site, Peter E. Schlichting, James C. Beasley, Raoul K. Boughton, Amy J. Davis, Kim M. Pepin, Michael P. Glow, Ryan S. Miller, Kurt C. Vercautern, Jesse S. Lewis

United States Department of Agriculture Wildlife Services: Staff Publications

Reliable and efficient population estimates are a critical need for effective management of invasive wild pigs (Sus scrofa). We evaluated the use of 10‐day camera grids for rapid population assessment (RPA) of wild pigs at 3 study sites that varied in vegetation communities and wild pig densities. Study areas included Buck Island Ranch, Florida; Tejon Ranch, California; and the Savannah River Site, South Carolina, USA, during 2016–2018. Rapid population assessments grids were composed of baited camera traps spaced approximately 500 or 750 m apart. Two RPA grids were deployed per study site and each grid was deployed twice (4–6 months …

Relationships Between Survival And Habitat Suitability Of Semi- Aquatic Mammals, Isidro Barela, Leslie M. Burger, Jimmy Taylor, Kristine O. Evans, Ryo Ogawa, Lance Mcclintic, Guiming Wang

United States Department of Agriculture Wildlife Services: Staff Publications

Spatial distribution and habitat selection are integral to the study of animal ecology. Habitat selection may optimize the fitness of individuals. Hutchinsonian niche theory posits the fundamental niche of species would support the persistence or growth of populations. Although niche-based species distribution models (SDMs) and habitat suitability models (HSMs) such as maximum entropy (Maxent) have demonstrated fair to excellent predictive power, few studies have linked the prediction of HSMs to demographic rates. We aimed to test the prediction of Hutchinsonian niche theory that habitat suitability (i.e., likelihood of occurrence) would be positively related to survival of American beaver (Castor canadensis), …

The Nebraska Bird Review, 2020 Annual Color Section

Nebraska Bird Review

Our theme this year is Odd Couples: two or more different species captured in the same photo frame. Examples appear on the first three pages of photos.

Blue Jay with Great Horned Owl in Plum Creek SRA, Dawson Co., 23 Dec. 2019. Photo by Elizabeth Winter.

Green Heron with Baltimore Oriole on Dark Island Trail, Merrick Co., June 2020. Photo by Colleen Childers.

Wilson’s Phalarope surrounded by Longbilled Dowitchers and Stilt Sandpipers along highway 30 east of North Platte, Lincoln Co., 12 May 2020. Photo by Boni Edwards.

Downy Woodpecker with Carolina Wren on suet feeder in photographer’s yard, La …

Winter Field Report, December 2019-February 2020, W. Ross Silcock

Nebraska Bird Review

As with any of these Seasonal Reports, there was plenty to entertain us and to contemplate this winter. The most obvious feature of this winter’s reports was the taxonomically widespread incidence of midwinter occurrences of species normally absent at that time. Snow, Ross’s, and Greater White-fronted Geese occurred in good numbers, and Jan to early Feb reports of dabbling and diving ducks often far from expected winter occurrence locations were notable. Among passerines, notable midwinter reports were of Gray Catbird, Brown Thrasher, and Northern Mockingbird, Nebraska’s first record for Feb of American Pipit, and 6th winter record of Lesser Goldfinch. …

2019-2020 Christmas Bird Counts, Don Paseka

Nebraska Bird Review

Mergansers reached a new high of 104 counted in nine circles, which topped the count of 97 from 2017. A single Surf Scoter was found in the Lower Platte circle, which was only the fourth time that this species has been found on a Nebraska CBC. Lone birds were also found at Lake McConaughy in 1999, 2010 and 2015. A good North Platte find were two Barrow’s Goldeneye. Several species, however, were counted in numbers much below the norm. The lone Wood Duck found at Branched Oak was the lowest count for that species since 2004, when they were missed …

Effects Of Inactivated Mycobacterium Bovis Vaccination On Molokai-Origin Wild Pigs Experimentally Infected With Virulent M. Bovis, Pauline Nol, Morgan Wehte, Richard A. Bowen, Suelee Robbe-Austerman, Tyler Thacker, Kristina Lantz, Jack Rhyan, Laurie A. Baeten, Ramón A. Juste, Iker A. Sevilla, Christian Gortazar, Joaquín Vicente

United States Department of Agriculture Wildlife Services: Staff Publications

The wild pig population on Molokai, Hawaii, USA is a possible reservoir for bovine tuberculosis, caused by Mycobacterium bovis, and has been implicated in decades past as the source of disease for the island’s domestic cattle. Heat-inactivated vaccines have been effective for reducing disease prevalence in wild boar in Spain and could prove useful for managing M. bovis in Molokai wild pigs. We designed an experiment to test this vaccine in wild pigs of Molokai genetics. Fifteen 3–4-month-old pigs were orally administered 10⁶–10⁷ colony forming units (cfu) of heat-inactivated M. bovis (Vaccinates; n = 8; 0.2 …

Rabies Management Implications Based On Raccoon Population Density Indexes, Dennis Slate, Brandi D. Saidy, Ashlee Simmons, Kathleen M. Nelson, Amy Davis, Timothy P. Algeo, Stacey A. Elmore, Richard B. Chipman

United States Department of Agriculture Wildlife Services: Staff Publications

An estimate or index of target species density is important in determining oral rabies vaccination (ORV) bait densities to control and eliminate specific rabies variants. From 1997–2011, we indexed raccoon (Procyon lotor) densities 253 times based on cumulative captures on 163 sites from Maine to Alabama, USA, near ORV zones created to prevent raccoon rabies from spreading to new areas. We conducted indexing under a common cage trapping protocol near the time of annual ORV to aid in bait density decisions. Unique raccoons (n = 8,415) accounted for 68.0% of captures (n = 12,367). We recaptured raccoons 2,669 times. We …

Economic Estimates Of Invasive Wild Pig Damage To Crops In 12 Us States, Sophie Mckee, Aaron Anderson, Keith Carlisle, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

We report the results of a survey on invasive wild pig (Sus scrofa L.) damage and control in 12 US states (Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, and Texas). The crops chosen for this study represent the “second-tier” in terms of economic importance after the six crops that were the subject of Anderson et al. (2016). The survey was distributed by the USDA National Agricultural Statistical Service (NASS) in the summer of 2019 to a sample of producers in each of the states (except California) of the following six crops: hay, pecans (Carya …

Individual And Population Fitness Consequences Associated With Large Carnivore Use Of Residential Development, Heather Johnson, David L. Lewis, Stewart W. Breck

United States Department of Agriculture Wildlife Services: Staff Publications

Large carnivores are negotiating increasingly developed landscapes, but little is known about how such behavioral plasticity influences their demographic rates and population trends. Some investigators have suggested that the ability of carnivores to behaviorally adapt to human development will enable their persistence, and yet, others have suggested that such landscapes are likely to serve as population sinks or ecological traps. To understand how plasticity in black bear (Ursus americanus) use of residential development influences their population dynamics, we conducted a 6-yr study near Durango, Colorado, USA. Using space-use data on individual bears, we examined the influence of use of residential …

Effects Of Deepwater Horizon Oil On Feather Structure And Thermoregulation In Gulls: Does Rehabilitation Work?, Katherine Horak, Nicole L. Barrett, Jeremy W. Ellis, Emma M. Campbell, Nicholas G. Dannemiller, Susan A. Shriner

United States Department of Agriculture Wildlife Services: Staff Publications

Impacts of large-scale oil spills on avian species are far-reaching.While media attention often focuses on lethal impacts, sub-lethal effects and the impacts of rehabilitation receive less attention. The objective of our study was to characterize effects of moderate external oiling and subsequent rehabilitation on feather structure and thermoregulation in gulls. We captured 30 wild ring-billed gulls (Larus delawarensis) and randomly assigned each individual to an experimental group: 1) controls, 2) rehabilitated birds (externally oiled, rehabilitated by washing), or 3) oiled birds (externally oiled, not rehabilitated). We externally oiled birds with weathered MC252 Deepwater Horizon oil (water for controls) …

Migratory Flyways May Affect Population Structure In Double‐Crested Cormorants, Steven J.A. Kimble, Brian S. Dorr, Katie C. Hanson-Dorr, Olin E. Rhodes Jr., Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Double‐crested cormorants (Phalacrocorax auritus) recovered from a demographic bottleneck so well that they are now considered a nuisance species at breeding and wintering grounds across the United States and Canada. Management of this species could be improved by refining genetic population boundaries and assigning individuals to their natal population. Further, recent radio‐telemetry data suggest the existence of Interior and Atlantic migratory flyways, which could reduce gene flow and result in substantial genetic isolation. In this study, we used 1,784 individuals collected across the eastern United States, a large panel of microsatellite markers developed for this species, and individuals banded as …

Optimal Bait Density For Delivery Of Acute Toxicants To Vertebrate Pests, Kim M. Pepin, Nathan P. Snow, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Oral baiting is a fundamental method for delivering toxicants to pest species. Planning baiting strategies is challenging because bait-consumption rates depend on dynamic processes including space use and demographics of the target species. To determine cost-effective strategies for optimizing baiting, we developed a spatially explicit model of population dynamics using field-based measures of wild-pig (Sus scrofa) space use, bait consumption, and mortality probabilities. The most cost-effective baiting strategy depended strongly on the population reduction objective and initial density. A wide range of baiting strategies were cost-effective when the objective was 80% population reduction. In contrast, only a narrow range of …

Brodifacoum Residues In Fish Three Years After An Island-Wide Rat Eradication Attempt In The Tropical Pacific, Shane R. Siers, Aaron B. Shiels, Steven F. Volker, Kristen Rex, William C. Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive rats are known to threaten natural resources and human health and safety. Island-wide rat eradication attempts have been increasing in number and scale during the past several decades, as has the frequency of eradication success. The most common method to remove all rats from an island is to broadcast anticoagulant rodenticide bait into every rat’s home range on the island. Broadcast of toxicants can put humans and other nontarget species in marine and terrestrial environments at risk of exposure. The persistence of anticoagulant residues is somewhat unknown, particularly in marine environments. Three years after ~ 18,000 kg of 25 …

Local Adaptation Constrains Drought Tolerance In A Tropical Foundation Tree, Kasey E. Barton, Casey Jones, Kyle F. Edwards, Aaron B. Shiels, Tiffany Knight

United States Department of Agriculture Wildlife Services: Staff Publications

1. Plant species with broad climatic ranges might be more vulnerable to climate change than previously appreciated due to intraspecific variation in climatic stress tolerance. In tropical forests, drought is increasingly frequent and severe, causing widespread declines and altering community dynamics. Yet, little is known about whether foundation tropical trees vary in drought tolerance throughout their distributions, and how intraspecific variation in drought tolerance might contribute to their vulnerability to climate changE.
2. We tested for local adaptation in seedling emergence and establishment with a full-factorial reciprocal transplant experiment including 27 populations and 109,350 seeds along a 3,500 mm precipitation gradient for …

Gulls As Sources Of Environmental Contamination By Colistin-Resistant Bacteria, Alan B. Franklin, Andrew M. Ramey, Kevin T. Bentler, Nicole L. Barrett, Loredana M. Mccurdy, Christina A. Ahlstrom, Jonas Bonnedahl, Susan A. Shriner, Jeffrey C. Chandler

United States Department of Agriculture Wildlife Services: Staff Publications

In 2015, the mcr-1 gene was discovered in Escherichia coli in domestic swine in China that conferred resistance to colistin, an antibiotic of last resort used in treating multi-drug resistant bacterial infections in humans. Since then, mcr-1 was found in other human and animal populations, including wild gulls. Because gulls could disseminate the mcr-1 gene, we conducted an experiment to assess whether gulls are readily colonized with mcr-1 positive E. coli, their shedding patterns, transmission among conspecifics, and environmental deposition. Shedding of mcr-1 E. coli by small gull flocks followed a lognormal curve and gulls shed one strain >101 …

Piscivorous Bird Use Of Aquaculture And Natural Water Bodies In Mississippi, Paul C. Burr, Jimmy I. Avery, Garrett M. Street, Bronson K. Strickland, Brian S. Dorr

United States Department of Agriculture Wildlife Services: Staff Publications

Double crested cormorants (Phalacrocorax auritus) and great egrets (Ardea alba) have an extensive history of human wildlife conflict with the aquaculture industry of western Mississippi, USA, due to

their depredation of cultured catfish (Ictalurus spp.). Although aquaculture is abundant, western Mississippi also contains naturally occurring water bodies that offer alternative forage opportunities to these species. How cormorants or egrets distribute themselves among these 2 foraging options is unknown, but it has been generally assumed each species uses aquaculture disproportionately more because of the high density of available prey. To test this assumption, we surveyed these …

Control Or Eradication: Problems In The Management Of Invasive Birds, Michael L. Avery, Chris J. Feare

United States Department of Agriculture Wildlife Services: Staff Publications

Humans have captured, transported and intentionally released wild birds for centuries (Blackburn et al., 2009). Motivations for such purposeful introductions include food (West and Zhou, 2007), religion (Agoramoorthy and Hsu, 2007), sport (McDowall, 1994), biocontrol (Bennett and Hughes, 1959; Kurdila, 1995) and aesthetics (Ryan, 1906; Thomson, 1922). Many purposeful bird introductions were the work of acclimatization societies, particularly in North America, New Zealand and Australia. These societies were formed in the 19th century by European settlers to transport bird species from their homelands in efforts to establish them in the newly settled regions (Thomson, 1922; Dunlap, 1997). As a result …

Spring Field Report, March-May 2020, W. Ross Silcock

Nebraska Bird Review

Although there were numerous early arrival dates, most were in the range of historically earliest expected dates; notable, however, was a lone record-early Whiterumped Sandpiper, nicely photographed. Record late by a month was a juvenile Redtailed (Harlan’s) Hawk, also confirmed by photo. Perhaps most prominent this spring were the large numbers of several species. Most eye-popping were record spring totals of 22 Glossy Ibises, 11 Yellow-bellied Flycatchers, 14 Veeries, including five in the Panhandle, 48 Gray-cheeked Thrushes, 20 Bay-breasted Warblers, not long ago a rare bird in spring, 45 Golden-winged Warblers and 27 Canada Warblers, both of which were about …