Physical Sciences and Mathematics Commons^™

Host Density Dependence And Environmental Factors Affecting Laurel Wilt Disease Incidence, Robin A. Choudhury, H. L. Er, M. Hughes, J. A. Smith, G. E. Pruett, J. Konkol, R. C. Ploetz, J. J. Marois, K. A. Marois, A. H. C. Van Bruggen

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Host size, density, and distribution, in addition to climate, can affect the likelihood a pathogen will invade and saturate landscapes. Laurel wilt, caused by the vector‐borne pathogen Raffaelea lauricola, has devastated populations of native Lauraceae in the Southeastern US, and continues to spread. We surveyed 87 plots in six coastal islands in South Carolina, Georgia, and North Florida, and one inland site (Archbold Biological Station) in South Florida for laurel wilt‐affected and non‐affected individual plants belonging to the genus Persea. The coastal island sites were surveyed once in 2008 or 2009, and the inland site was surveyed eight …

Evaluating Airsoft Electric Guns For Control Of Invasive Brown Treesnakes, Adam J. Knox, Björn Lardner, Amy Yackel Adams, Robert N. Reed

United States Geological Survey: Staff Publications

Firearms are often used in lethal control of invasive vertebrates, but safety and regulatory aspects limit the circumstances under which they can be used. During August 2016 at the Brown Treesnake Project laboratory on Guam, we evaluated hobby‐grade Airsoft Electric Guns (AEGs; a lower powered, less‐hazardous, and less‐regulated alternative to firearms) for capture and control of small animals, with specific emphasis on invasive brown treesnakes (Boiga irregularis). Tests of AEGs differing in power with ammunition (plastic pellets) masses ranging from 0.20 to 0.39 g, fired at gelatin blocks from distances of 4, 8, and 12 m, showed that …

Genetic Biocontrol For Invasive Species, John L. Teem, Luke Alphey, Sarah Descamps, Matt P. Edgington, Owain Edwards, Neil Gemmell, Tim Harvey-Samuel, Rachel L. Melnick, Kevin P. Oh, Antoinette J. Piaggio, J. Royden Saah, Dan Schill, Paul Thomas, Trevor Smith, Andrew Roberts

USDA Wildlife Services: Staff Publications

Invasive species are increasingly affecting agriculture, food, fisheries, and forestry resources throughout the world. As a result of global trade, invasive species are often introduced into new environments where they become established and cause harm to human health, agriculture, and the environment. Prevention of new introductions is a high priority for addressing the harm caused by invasive species, but unfortunately efforts to prevent new introductions do not address the economic harm that is presently manifested where invasive species have already become established. Genetic biocontrol can be defined as the release of organisms with genetic methods designed to disrupt the reproduction …

Photographic Validation Of Target Versus Nontarget Take Of Brown Treesnake Baits, Shane R. Siers, Aaron B. Shiels, Cynthia G. Payne, Francinem M. Chlarson, Craig S. Clark, Stephen M. Mosher

USDA Wildlife Services: Staff Publications

Use of toxic baits or other tools for managing nuisance species must ensure that the species of interest is adequately targeted while exposure to nontarget species is minimized. Nontarget takes of acetaminophen‐laced baits for control of invasive brown treesnakes (Boiga irregularis) on Guam may put those animals at risk of lethal intoxication and render the bait unavailable to the intended target species. We used wildlife cameras to identify species removing toxic and nontoxic baits from brown treesnake bait stations designed to exclude nontarget taxa in 2015 and 2016. Throughout various sites and habitat types, and balanced by season (wet vs. …

Time Allocation To Resources By Three Species Of Rats (Rattus Spp.) In A Radial Arm Maze, Gary Witmer, Nathan P. Snow, Rachael S. Moulton

USDA Wildlife Services: Staff Publications

Context. Introduced rats (Rattus spp.) can pose a serious threat to native flora and fauna, especially on islands where most species have evolved in the absence of terrestrial predators. Effective detection and eradication methods for introduced rats are essential to the maintenance of insular ecosystem integrity. Thus, it is important to better understand the behaviour of rats when they first arrive in a new setting.

Aims. To determine whether rats would find some novel stimuli to be significantly more attractive than other novel stimuli.

Methods. An eight-arm radial maze was used to study the behaviour of three species of Rattus …

An Analysis Of Temperate Deciduous Shrub Phenology In Downer Woods, University Of Wisconsin-Milwaukee, Wisconsin, Usa, Chloe Rehberg

Theses and Dissertations

Shrub species, both native and non-native, are an important component of temperate deciduous forest ecosystems but are an often-overlooked and under-studied functional group. Shrubs tend to leaf-out earlier than trees in spring and retain their leaves later in autumn thus extending the overall growing season and the carbon uptake period of the forest ecosystem. In this study, a range of 5- native and 3- non-native shrub species were identified in a deciduous urban woodlot, and the phenology was monitored over a 3-year period on the University of Wisconsin-Milwaukee campus. The aim of this work was to determine any variation in …

Biogeography Of Biological Control: Spatial Variation In Agent-Host Interactions, Nathan Harms

LSU Doctoral Dissertations

Management of plant invasions using biological control has the potential to generate spatial patterns which reflect geographic or genetic variation in invader or control agents. Despite its rarity in practice, investigations into the biogeography of interacting species (i.e., plant invader and control agent) in the context of biological control can lend insights into species distribution-abundance patterns and provide predictions for spatial variation in control success. I explored spatial variability in biological control agent-plant interactions using two wetland weed study systems with large geographic distributions: flowering rush (Butomus umbellatus L.) and alligatorweed (Alternanthera philoxeroides (Mart.) Griseb). Through literature and …

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

USDA 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 …

Effects Of Culling White-Tailed Deer On Tree Regeneration And Microstegium Vimineum, An Invasive Grass, John Paul Schmit, Elizabeth R. Matthews, Andrejs Brolis

United States National Park Service: Publications

Reduction of forest regeneration due to overbrowsing by white-tailed deer is a growing concern for land managers. Abundant deer can impede forest regeneration through direct predation on tree seedlings. Additionally high deer density can facilitate the establishment of a dense understory of browse tolerant plant species that shades seedlings and persists even in the absence of deer. In response to these challenges, land managers have sought to reduce deer herds to restore tree regeneration, but few studies have evaluated the effectiveness of this management. Our study took place in Catoctin Mountain Park, a US National Park Service unit with a …

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

USDA 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 …

Automated Aerial Baiting For Invasive Brown Treesnake Control: System Overview And Program Status, Shane R. Siers, John D. Eisemann, William C. Pitt, Larry Clark, Scott M. Goetz, Robert J. Gosnell, Aaron F. Collins, Eric T. Hileman, Melia G. Nafus, Amy A. Yackel Adams, Michael C. Messaros, William G.N. Coon

Proceedings of the Twenty-Ninth Vertebrate Pest Conference (2020)

The economically and ecologically catastrophic introduction of invasive brown treesnakes to the Pacific Island of Guam has long served as a cautionary tale about the dangers of invasive species and the seeming impossibility of their management on a landscape scale. USDA Wildlife Services and federal and private partners have engineered a system for the automated manufacture and aerial delivery of toxic baits for landscape-scale suppression of brown treesnakes in large and remote forest plots. The helicopter-borne dispensing module can launch four bait cartridges per second, and a single payload of 3,600 cartridges can treat 30 ha of forest at 120 …

Development And Testing Of A Matrix For Mongoose Toxic Bait: Nontoxic Bait Acceptance Cage Trials, Shane Siers, Robert T. Sugihara, Israel Leinbach, Daniel Sedgwick, Chris N. Niebuhr, Emily W. Ruell

Proceedings of the Twenty-Ninth Vertebrate Pest Conference (2020)

The only pesticide currently registered for mongoose control is a product developed for rats that consists of a hard-cereal bait block. Although the active ingredient (diphacinone) is known to be highly effective for mongoose, previous studies indicate that carnivorous and omnivorous mongooses do not readily consume the hard bait matrix designed for gnawing rodents. A palatable bait matrix with a consistency more appropriate to mongoose dentition and feeding behavior will be required to develop a more effective mongoose pesticide. We evaluated the acceptance and consumption of nontoxic versions of four candidate bait matrices: FOXECUTE® and FOXSHIELD® (Animal Control Technologies, Australia; …

Feasibility Of A Successful Rat Eradication On Wake Atoll Following Initial Partial Failure: Potential Causes, Remedial Actions, And Remaining Knowledge Gaps, Chad Hanson, Kristen Rex, Peter J. Kappes, Shane R. Siers

Proceedings of the Twenty-Ninth Vertebrate Pest Conference (2020)

A 2012 attempt to remove two rat species (Rattus tanezumi and R. exulans) from Wake Atoll was partially successful. R. tanezumi was eradicated from all three islands (Wake, Wilkes, and Peale), and R. exulans was eradicated from Peale. However, R. exulans remained on Wake and Wilkes and have since recovered to very high densities. In 2013, a panel of experts reviewed the eradication operation and offered a list of possible causes of the partial failure. Since that time, further research has been conducted to address several of the issues identified in the review. In this paper, we conduct a current …

Placebo Bait Uptake Trial To Test Feasibility Of Polynesian Rat (Rattus Exulans) Eradication On Wake Atoll, Chris N. Niebuhr, Israel Leinbach, Thomas W. Mcauliffe, Dean K. Foster, Shane R. Siers

Proceedings of the Twenty-Ninth Vertebrate Pest Conference (2020)

Rodent eradications have contributed to the recovery of many threatened species, but challenges often exist for campaigns that occur on tropical islands when compared to more temperate regions. A post-operational review of a rat eradication operation on Wake Atoll indicated that certain areas, such as those with high alternative food abundance, may have contributed to the failure to remove all Polynesian rats. We conducted a nontoxic bait uptake trial to evaluate whether the maximum prescribed bait application rate for Brodifacoum-25W rodenticide pellets was sufficient to expose all rats to a lethal dose at three sites on Wake Atoll, including around …

Mixed Ancestry From Wild And Domestic Lineages Contributes To The Rapid Expansion Of Invasive Feral Swine, Timothy J. Smyser, Michael A. Tabak, Chris Slootmaker, Michael S. Robeson Ii, Ryan S. Miller, Mirte Bosse, Hendrik-Jan Megens, Martien A.M. Groenen, Samuel Rezende Paiva, Danielle Assis De Faria, Harvey D. Blackburn, Brandon S. Schmit, Antoinette J. Piaggio

USDA Wildlife Services: Staff Publications

Invasive alien species are a significant threat to both economic and ecological systems. Identifying the processes that give rise to invasive populations is essential for implementing effective control strategies. We conducted an ancestry analysis of invasive feral swine (Sus scrofa, Linnaeus, 1758), a highly destructive ungulate that is widely distributed throughout the contiguous United States, to describe introduction pathways, sources of newly emergent populations and processes contributing to an ongoing invasion. Comparisons of high-density single nucleotide polymorphism genotypes for 6,566 invasive feral swine to a comprehensive reference set of S. scrofa revealed that the vast majority of feral swine were …

Movement Behavior Of Radio-Tagged European Starlings In Urban, Rural, And Exurban Landscapes, Page E. Klug, H. Jeffrey Homan

USDA Wildlife Services: Staff Publications

Since their intentional introduction into the United States in the 1800s, European starlings (Sturnus vulgaris) have become the fourth most common bird species and a nuisance bird pest in both urban and rural areas. Managers require better information about starling movement and habit-use patterns to effectively manage starling populations and the damage they cause. Thus, we revisited 6 radio-telemetry studies conducted during fall or winter between 2005 and 2010 to compare starling movements (n = 63 birds) and habitat use in 3 landscapes. Switching of roosting and foraging sites in habitat-sparse rural landscapes caused daytime (0900–1500 hours) …

Optimal Spatial Prioritization Of Control Resources For Elimination Of Invasive Species Under Demographic Uncertainty, Kim M. Pepin, Timothy J. Smyser, Amy J. Davis, Ryan S. Miller, Sophie Mckee, Kurt C. Vercauteren, William Kendall, Chris Slootmaker

USDA Wildlife Services: Staff Publications

Populations of invasive species often spread heterogeneously across a landscape, consisting of local populations that cluster in space but are connected by dispersal. A fundamental dilemma for invasive species control is how to optimally allocate limited fiscal resources across local populations. Theoretical work based on perfect knowledge of demographic connectivity suggests that targeting local populations from which migrants originate (sources) can be optimal. However, demographic processes such as abundance and dispersal can be highly uncertain, and the relationship between local population density and damage costs (damage function) is rarely known. We used a metapopulation model to understand how budget and …

One Step Closer To A Better Starling Trap, James R. Thiele

USDA Wildlife Services: Staff Publications

European starlings (Sturnus vulgaris) are an invasive species in the United States that damage agriculture, personal property, and threaten human health and safety. The U.S. Department of Agriculture Wildlife Services provides technical support to mitigate damage by controlling starling populations at concentrated animal feeding operations, landfills, utilities, and urban areas. Wildlife Services uses DRC-1339, a registered toxicant, to reduce starling populations. Trapping can also be an effective tool but requires more time at a higher cost than DRC-1339. Trapping starlings, however, may be needed to provide a viable alternative to mitigate damage in areas where toxicant use may …

Plant Invasion Impacts On Fungal Community Structure And Function Depends On Soil Warming And Nitrogen Enrichment, M. A. Anthony, K. A. Stinson, J. A. M. Moore, S. D. Frey

Environmental Conservation Faculty Publication Series

The impacts of invasive species on biodiversity may be mitigated or exacerbated by abiotic environmental changes. Invasive plants can restructure soil fungal communities with important implications for native biodiversity and nutrient cycling, yet fungal responses to invasion may depend on numerous anthropogenic stressors. In this study, we experimentally invaded a long-term soil warming and simulated nitrogen deposition experiment with the widespread invasive plant Alliaria petiolata (garlic mustard) and tested the responses of soil fungal communities to invasion, abiotic factors, and their interaction. We focused on the phytotoxic garlic mustard because it suppresses native mycorrhizae across forests of North America. We …

Effects Of Wild Pig Disturbance On Forest Vegetation And Soils, Steven M. Gray, Gary J. Roloff, Daniel B. Kramer, Dwayne R. Etter, Kurt C. Vercauteren, Robert A. Montgomery

USDA Wildlife Services: Staff Publications

In North America, wild pigs (Sus scrofa; feral pigs, feral swine, wild boars) are a widespread exotic species capable of creating large‐scale biotic and abiotic landscape perturbations. Quantification of wild pig environmental effects has been particularly problematic in northern climates, where they occur only recently as localized populations at low densities. Between 2016 and 2017, we assessed short‐term (within ~2 yrs of disturbance) effects of a low‐density wild pig population on forest features in the central Lower Peninsula of Michigan, USA. We identified 16 8‐ha sites using global positioning system locations from 7 radio‐collared wild pigs for sampling.Within each …

Vegetation Surveys In Southern Minnesota Prairies: Management, Invasive Species And Future Directions, Ainsley Peterson

All Graduate Theses, Dissertations, and Other Capstone Projects

This paper is formatted into two chapters: a general introduction on prairies, management, and this study (Chapter 1), and the study formatted for submission to a journal for publication (Chapter 2). To manage habitat loss in Southern Minnesota prairies, and subsequent ecological damage, private and public individuals have responded with restoration. This study investigated the use of an accepted vegetation monitoring tool to survey prairies (N=31) in Southern Minnesota during June/July (2019), targeting peak growing season to see whether restored prairies had lower invasive species richness, and relatively greater native richness. We hypothesized that restored prairies would have higher species …

An Investigation Into The Spatial Distribution, Habitat Selection And Resource Usage Of The Red Fox (Vulpes Vulpes) Inhabiting Urban Reserves Within Perth, Western Australia, Michael Thomas Main

Theses: Doctorates and Masters

I attempted to track a population of urban foxes in Kings Park, but due to collar failure, only one collar was retrieved. The GPS telemetry data from this fox produced home range estimates for minimum convex polygon (MCP) and kernel density (KD) of 0.302 km² and 0.331 km², respectively. The fox was predominantly active at night, with a ten-fold increase in movement during nocturnal periods when compared to daytime movements. Roads and man-made tracks were important for facilitating movement of the fox through its home range, with almost 97% of location fixes recorded within 100m of these features. The fox …