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Full-Text Articles in Physical Sciences and Mathematics

Movements And Resource Selection Of Wild Pigs Associated With Growth Stages Of Corn, Bethany A. Friesenhahn, Randall W. Deyoung, Michael J. Cherry, Humberto L. Perotto-Baldivieso, Kurt C. Vercauteren, Nathan P. Snow Jan 2023

Movements And Resource Selection Of Wild Pigs Associated With Growth Stages Of Corn, Bethany A. Friesenhahn, Randall W. Deyoung, Michael J. Cherry, Humberto L. Perotto-Baldivieso, Kurt C. Vercauteren, Nathan P. Snow

USDA Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are one of the most successful invasive species globally and are often implicated in agricultural damage. This damage is expected to increase as ranges of wild pigs expand, impacting the human food supply and increasing costs of food production. Our objective was to evaluate movement behaviors of wild pigs relative to resource availability and landscape features in an agriculture-dominated landscape, with a goal of informing management practices for reducing damage to corn. We monitored hourly movements of adult wild pigs relative to corn crops using GPS collars during the 2019 and 2020 growing seasons (Feb–Sept) in …


Using Drones To Detect And Quantify Wild Pig Damage And Yield Loss In Corn Fields Throughout Plant Growth Stages, Bethany A. Friesenhahn, Lori D. Massey, Randy W. Deyoung, Michael J. Cherry, Justin W. Fischer, Nathan P. Snow, Kurt C. Vercauteren, Humberto L. Perotto‐Baldivieso Jan 2023

Using Drones To Detect And Quantify Wild Pig Damage And Yield Loss In Corn Fields Throughout Plant Growth Stages, Bethany A. Friesenhahn, Lori D. Massey, Randy W. Deyoung, Michael J. Cherry, Justin W. Fischer, Nathan P. Snow, Kurt C. Vercauteren, Humberto L. Perotto‐Baldivieso

USDA Wildlife Services: Staff Publications

Presently, there are an estimated 6.9 million wild pigs (Sus scrofa) in the U.S., which cause over US$1 billion in damage to agriculture, environmental impacts, and control costs. However, estimates of damage have varied widely, creating a need for standardized monitoring and a method to accurately estimate the economic costs of direct wild pig damage to agriculture. The goal of our study was to integrate remotely sensed imagery from drones and crop harvest data to quantify wild pig damage in corn fields. We used drones with natural color (red, green, blue) cameras to monitor corn fields at different …


Investigating Nocturnal Uas Treatments In An Applied Context To Prevent Gulls From Nesting On Rooftops, Morgan Pfeiffer, Craig K. Pullins, Scott F. Beckerman, Joshua L. Hoblet, Brad Blackwell Jan 2023

Investigating Nocturnal Uas Treatments In An Applied Context To Prevent Gulls From Nesting On Rooftops, Morgan Pfeiffer, Craig K. Pullins, Scott F. Beckerman, Joshua L. Hoblet, Brad Blackwell

USDA Wildlife Services: Staff Publications

Ring‐billed (Larus delawarensis) and herring (L. argentatus) gulls are numerous and widespread in North America. These gulls rank among the top 9 species for risk of bird‐aircraft collisions (hereafter strikes). The ubiquitous presence of gulls in urban coastal environments, including rooftop nesting behavior, are factors impacting strike risk. Our purpose was to assess gull response to a small uncrewed aircraft system (UAS) in hazing flights at night during the nest‐building phase. We hypothesized that nocturnal UAS operation, like nocturnal predator disturbance, might reduce gull numbers and, thus, strike risk to aircraft. In spring 2021, we conducted …


Improving Efficiency Of Prairie Dog Surveys By Using A Small Copter Drone, Aaron B. Shiels, J. W. Fischer, Danika Spock, Meagan Allira Jan 2022

Improving Efficiency Of Prairie Dog Surveys By Using A Small Copter Drone, Aaron B. Shiels, J. W. Fischer, Danika Spock, Meagan Allira

USDA Wildlife Services: Staff Publications

Prairie dogs are an accessible and enjoyed wildlife species in Colorado that require occasional surveys because populations can change abruptly due to plague outbreaks or human-induced control. We evaluated the use of small copter drones at four prairie dog colonies on Open Space and Mountain Parks lands, City of Boulder, to determine if this methodology improves efficiency over ground-based survey methods. We counted prairie dogs and burrows using two types of drones (DJI Matric 210 and Autel Evo II) at altitudes 100', 150', and 400' (burrows only). We recorded video and merged still images into orthomosaics prior to having USDA …


Concentration-Response Of An Anthraquinone-Based Repellent For Raccoons (Procyon Lotor), Shylo Johnson, Shelagh T. Deliberto, Kathleen Urchek, Amy T. Gilbert, Scott J. Werner Jan 2022

Concentration-Response Of An Anthraquinone-Based Repellent For Raccoons (Procyon Lotor), Shylo Johnson, Shelagh T. Deliberto, Kathleen Urchek, Amy T. Gilbert, Scott J. Werner

USDA Wildlife Services: Staff Publications

Wildlife repellents can be part of non-lethal management strategies to reduce the negative impacts of wildlife to property, agricultural production, and human health and safety. Raccoons (Procyon lotor) are associated with negative impacts in all three of these areas. Anthraquinone is a useful avian repellent and its utility as a mammalian repellent is still being explored. Our objective was to evaluate laboratory efficacy of an anthraquinone-based repellent for raccoons using different concentrations. We fed captive raccoons whole corn treated at 0.5%, 1%, 1.5% and 2% anthraquinone and examined their behavioral response related to feeding repellency including consumption and change in …


Scaup Depredation On Arkansas Baitfish And Sportfish Aquaculture, Stephen A. Clements, Brian S. Dorr, J. Brian Davis, Luke A. Roy, Carole R. Engle, Katie C. Hanson-Dorr, Anita M. Kelly Sep 2021

Scaup Depredation On Arkansas Baitfish And Sportfish Aquaculture, Stephen A. Clements, Brian S. Dorr, J. Brian Davis, Luke A. Roy, Carole R. Engle, Katie C. Hanson-Dorr, Anita M. Kelly

USDA Wildlife Services: Staff Publications

Lesser scaup (Aythya affinis) and greater scaup (A. marila), hereafter scaup, consume a variety of aquatic invertebrates, plants, and occasionally small fish. Scaup have foraged on commercial aquaculture farms in the southern United States for decades. However, the types, abundance, and rate of fish exploitation by scaup on baitfish and sportfish farms are not well documented. Thus, information is needed to understand how fish and other foods influence scaup use of aquatic resources, and any potential economic effects of depredation of fish. From November–March in winters 2016–2017 and 2017–2018, we conducted 1,458 pond surveys to estimate …


Anthraquinone Repellent Seed Treatment On Corn Reduces Feeding By Wild Pigs, Nathan P. Snow, Joseph M. Halseth, Scott J. Werner, Kurt C. Vercauteren Jan 2021

Anthraquinone Repellent Seed Treatment On Corn Reduces Feeding By Wild Pigs, Nathan P. Snow, Joseph M. Halseth, Scott J. Werner, Kurt C. Vercauteren

USDA Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are a destructive invasive species that cause extensive damage to agriculture throughout many regions of the world. In particular wild pigs damage corn more than any other crop, and most of that damage occurs immediately after planting when wild pigs excavate and consume planted seeds. We evaluated whether anthraquinone (AQ), a repellent, could be useful for protecting seed corn from consumption by wild pigs. Specifically, we conducted cafeteria-style tests at 16 bait sites for 6 nights using concentrations of: untreated, 0.5, 1.5, and 3.0% AQ by weight sprayed on whole-kernel corn in AL and …


Daily And Landscape Influences Of Species Visitation To Toxic Bait Sites For Wild Pigs, Nathan P. Snow, Joseph M. Halseth, Michael P. Glow, Michael Lavelle, Justin Fischer, Eric H. Vannatta, Kurt C. Vercauteren Jan 2021

Daily And Landscape Influences Of Species Visitation To Toxic Bait Sites For Wild Pigs, Nathan P. Snow, Joseph M. Halseth, Michael P. Glow, Michael Lavelle, Justin Fischer, Eric H. Vannatta, Kurt C. Vercauteren

USDA Wildlife Services: Staff Publications

Toxic baiting of wild pigs (Sus scrofa) is a potential new tool for population control and damage reduction in the United States. Use of toxic bait sites by non‐target species is concerning because of the risks posed from exposure to a toxic bait. A 2018 field trial in northern Texas, USA, examining the efficacy of a prototype toxic bait (HOGGONE®, containing 10% sodium nitrite) revealed unexpected hazards to non‐target species, primarily passerine birds, from consuming toxic bait spilled outside of bait stations by wild pigs. The hazards jeopardize the ability to register HOGGONE as a tool for controlling …


Improved Strategies For Handling Entire Sounders Of Wild Pigs, Michael Lavelle, Nathan P. Snow, Christine K. Ellis, Joe M. Halseth, Justin W. Fischer, Michael P. Glow, Eric H. Vannatta, Bethany A. Friesenhahn, Kurt C. Vercauteren Jan 2021

Improved Strategies For Handling Entire Sounders Of Wild Pigs, Michael Lavelle, Nathan P. Snow, Christine K. Ellis, Joe M. Halseth, Justin W. Fischer, Michael P. Glow, Eric H. Vannatta, Bethany A. Friesenhahn, Kurt C. Vercauteren

USDA Wildlife Services: Staff Publications

As wild pigs (Sus scrofa) expand throughout North America researchers are increasingly being tasked with trapping and marking entire sounders (family groups) to attach monitoring devices or other identifying markers to gather knowledge to inform management. Capture and marking procedures can be challenging, dangerous for both researchers and animals, and time consuming, particularly when handling sounders. We developed an integrated pig‐handling system to efficiently sort, weigh, chemically immobilize, and mark multiple wild pigs simultaneously in a controlled manner. To assess the functionality of the system, we evaluated 18 capture events in Texas, USA, from January 2018 to March …


Inefficiency Of Anthraquinone-Based Avian Repellents When Applied To Sunflower: The Importance Of Crop Vegetative And Floral Characteristics In Field Applications, Brandon Kaiser, Burton L. Johnson, Mike Ostlie, Scott J. Werner, Page E. Klug Jan 2021

Inefficiency Of Anthraquinone-Based Avian Repellents When Applied To Sunflower: The Importance Of Crop Vegetative And Floral Characteristics In Field Applications, Brandon Kaiser, Burton L. Johnson, Mike Ostlie, Scott J. Werner, Page E. Klug

USDA Wildlife Services: Staff Publications

BACKGROUND: Blackbirds (Icteridae) cause significant damage to sunflower (Helianthus annuus L.) prompting the need for effective management tools. Anthraquinone-based repellents can reduce feeding by > 80% in laboratory settings, but require birds to learn the negative association through repellent ingestion. We evaluated an anthraquinone-based repellent applied directly to mature sunflower plants for its ability to reduce bird damage. We used captive male red-winged blackbirds (Agelaius phoeniceus) to evaluate efficacy of two anthraquinone-based formulations in varying concentrations and applied in a manner attainable by sunflower producers. We also assessed field application methods for repellent coverage and anthraquinone residues when …


Distribution And Abundance Of Scaup Using Baitfish And Sportfish Farms In Eastern Arkansas, Stephen A. Clements, Brian S. Dorr, Brian Davis, Luke A. Roy, Carole R. Engle, Katie C. Hanson-Dorr, Anita M. Kelly Jan 2021

Distribution And Abundance Of Scaup Using Baitfish And Sportfish Farms In Eastern Arkansas, Stephen A. Clements, Brian S. Dorr, Brian Davis, Luke A. Roy, Carole R. Engle, Katie C. Hanson-Dorr, Anita M. Kelly

USDA Wildlife Services: Staff Publications

Arkansas' bait- and sportfish facilities are commonly used by various piscivorous bird species, including lesser scaup (Aythya affinis) and greater scaup (A. marila) that consume substantial quantities of fish. To mediate this predation, farmers implement extensive bird harassment programs that create additional costs to fish loss, thus research investigating the distribution and abundance of scaup is needed to help farmers allocate their bird harassment efforts more efficiently. In winters 2016–2017 and 2017–2018 we conducted 1,368 pond surveys to investigate pond use by scaup on farms during birds' regular wintering period (i.e., November–March). We used intrinsic and …


Scaup Depredation On Arkansas Baitfish And Sportfish Aquaculture, Stephen A. Clements, Brian S. Dorr, J. Brian Davis, Luke A. Roy, Carole R. Engle, Katie C. Hanson-Dorr, Anita M. Kelly Jan 2021

Scaup Depredation On Arkansas Baitfish And Sportfish Aquaculture, Stephen A. Clements, Brian S. Dorr, J. Brian Davis, Luke A. Roy, Carole R. Engle, Katie C. Hanson-Dorr, Anita M. Kelly

USDA Wildlife Services: Staff Publications

Lesser scaup (Aythya affinis) and greater scaup (A. marila), hereafter scaup, consume a variety of aquatic invertebrates, plants, and occasionally small fish. Scaup have foraged on commercial aquaculture farms in the southern United States for decades. However, the types, abundance, and rate of fish exploitation by scaup on baitfish and sportfish farms are not well documented. Thus, information is needed to understand how fish and other foods influence scaup use of aquatic resources, and any potential economic effects of depredation of fish. From November–March in winters 2016–2017 and 2017–2018, we conducted 1,458 pond surveys to estimate …


Efficacy And Risks From A Modified Sodium Nitrite Toxic Bait For Wild Pigs, Nathan P. Snow, Jason Wishart, Justin A. Foster, Linton D. Staples, Kurt C. Vercauteren Jan 2021

Efficacy And Risks From A Modified Sodium Nitrite Toxic Bait For Wild Pigs, Nathan P. Snow, Jason Wishart, Justin A. Foster, Linton D. Staples, Kurt C. Vercauteren

USDA Wildlife Services: Staff Publications

BACKGROUND: Wild pigs (Sus scrofa) are a destructive invasive species throughout many regions of the world. In 2018, a field evaluation of an early prototype of a sodium nitrite (SN) toxic bait in the United States revealed wild pigs dropped large amounts of the toxic bait outside the pig-specific bait stations while feeding, and thus subsequent hazards for non-target animals. We modified the SN-toxic bait formulation, the design of the bait station, and the baiting strategy to reduce dropped bait. We tested the modifications in Queensland, Australia (December 2018), Alabama, USA (August 2019), and Texas, USA (March 2020) …


Timing And Extent Of Crop Damage By Wild Pigs (Sus Scrofa Linnaeus) To Corn And Peanut Fields, C. M. Boyce, Kurt C. Vercauteren, James C. Beasley Jan 2020

Timing And Extent Of Crop Damage By Wild Pigs (Sus Scrofa Linnaeus) To Corn And Peanut Fields, C. M. Boyce, Kurt C. Vercauteren, James C. Beasley

USDA Wildlife Services: Staff Publications

The global expansion of wild pigs over the last few decades has resulted in an increase in extent and distribution of damages to crops, placing a growing strain on agricultural producers and land managers. Despite the extent of wild pig damage to agriculture, there is little data regarding timing and spatial variability of damage to corn (Zea mays Linnaeus) and we found no data regarding the effect of these factors on peanuts (Arachis hypogaea Linnaeus). Our objective was to determine the timing and extent of wild pig damage to corn and peanut fields, as well as the extent …


Application Strategy For An Anthraquinonebased Repellent And The Protection Of Soybeans From Canada Goose Depredation, Scott J. Werner, Matthew Gottlob, Charles D. Dieter, Joshua D. Stafford Oct 2019

Application Strategy For An Anthraquinonebased Repellent And The Protection Of Soybeans From Canada Goose Depredation, Scott J. Werner, Matthew Gottlob, Charles D. Dieter, Joshua D. Stafford

USDA Wildlife Services: Staff Publications

Agricultural crops can sustain extensive damage caused by Canada geese (Branta canadensis) when these crops are planted near wetlands or brood-rearing sites. From 2000 to 2015, South Dakota Game, Fish and Parks spent >$5.6 million to manage damages caused by Canada geese to agricultural crops (primarily soybeans) in South Dakota, USA. For the purpose of developing a repellent application strategy for nonlethal goose damage management, we comparatively evaluated the width of anthraquinone applications (i.e., 9.4 L Flight Control® Plus goose repellent/ha [active ingredient: 50% 9,10-anthraquinone] at 0–36 m versus 0–73 m perpendicular to the edge of wetlands in 2014), the …


Movement Responses Inform Effectiveness And Consequences Of Baiting Wild Pigs For Population Control, Nathan P. Snow, Kurt C. Vercauteren Jan 2019

Movement Responses Inform Effectiveness And Consequences Of Baiting Wild Pigs For Population Control, Nathan P. Snow, Kurt C. Vercauteren

USDA Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) damage agricultural and natural resources throughout their nearly global distribution. Subsequently, population control activities (e.g., trapping, shooting, or toxic baiting) frequently involve the deployment of bait to attract wild pigs. A better understanding of how wild pigs respond to bait sites can help maximize efficiency of baiting programs and identify any potential pitfalls. We examined the movement behaviors of 68 wild pigs during three stages of intensive baiting programs (i.e., 15 days each: prior, during, and post baiting) spread across two distinct study areas in southern and northern Texas, USA. We found that bait sites needed …


An Evaluation Of Two Traps And Sets For Trapping The Plains Pocket Gopher, Stephen M. Vantassel, Andrew J. Tyre, Scott E. Hygnstrom Apr 2014

An Evaluation Of Two Traps And Sets For Trapping The Plains Pocket Gopher, Stephen M. Vantassel, Andrew J. Tyre, Scott E. Hygnstrom

School of Natural Resources: Faculty Publications

We investigated the efficiency of DK-1 and Macabee® pocket gopher (Geomys bursarius) traps placed in lateral tunnels in both open and closed tunnel sets in rangeland and nonirrigated alfalfa fields in Nebraska. We observed no statistical difference between the traps in capture efficiency when used in open, versus closed, tunnel sets. Trapping of pocket gophers was more effective in rangeland (probability of capture in a single tunnel system using 3 traps; 63%) than nonirrigated alfalfa fields (26%). We did not determine whether this variance was due to behavioral differences between Geomys bursarius and Geomys lutescens. We found that trapping pocket …


Use Of Partially Fenced Fields To Reduce Deer Damage To Corn, Aaron M. Hildreth, Scott E. Hygnstrom, Erin E. Blankenship, Kurt C. Vercauteren Jan 2012

Use Of Partially Fenced Fields To Reduce Deer Damage To Corn, Aaron M. Hildreth, Scott E. Hygnstrom, Erin E. Blankenship, Kurt C. Vercauteren

School of Natural Resources: Faculty Publications

White-tailed deer (Odocoileus virginianus) damage agricultural crops, often leading to significant economic losses for farmers. We used poly-mesh fence with wings to separate good deer cover from agricultural fields where crop damage by deer occurred primarily along this edge. In these cases, complete enclosure of the field with fencing may be unnecessary. The design used a 2.13-m-high polypropylene mesh fence erected along the wooded edge of a field with either 50-m or 150-m wings extending perpendicular from the fence line and wooded habitat. Fences reduced deer damage in cornfields 13.5% (F1,6= , P < 0.001). Average yield in fenced fields (10,211 kg/ha) was 1,708 kg/ha greater than in control fields, which, at US$0.155/kg, equals a net gain of US$265/ha. We found no difference in damage between fences with 50-m and 150-m wings (F …


A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt May 2011

A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt

USDA Wildlife Services: Staff Publications

Techniques to monitor populations of feral swine (Sus scrofa) relative to damage control activities are needed on rangelands. Our objectives were to describe and assess a mark–recapture technique using tetracycline hydrochloride (TH) for monitoring feral swine populations. We established bait stations at study sites in southern and central Texas. During 1 d, we replaced normal soured corn bait with bait containing TH and counted the number of feral swine that consumed bait with observers. We conducted feral swine removal using box-style traps and helicopters, at which time we collected teeth for TH analysis. In southern Texas, we estimated …


Brown Treesnake Control: Economy Of Scales, Daniel S. Vice, Mikel E. Pitzler Aug 2000

Brown Treesnake Control: Economy Of Scales, Daniel S. Vice, Mikel E. Pitzler

Human Conflicts with Wildlife: 2002 Symposium

The accidental introduction of the brown treesnake (Boiga irregularis) to Guam led to the demise of most of the island’s native avifauna and herpetofauna. The snake is also responsible for significant economic losses through frequent power outages and consumption of poultry. Control of the snake, aimed at preventing its inadvertent dispersal from the island and protecting native wildlife and economic resources, is accomplished using specially designed snake traps, hand capture, snake detector dogs, and snake barriers. Although control tools capture large numbers of snakes, control efforts are labor intensive, costly, and ineffective in reducing snake populations across the …


Pieces Of Silver: Examples Of The Economic Impact And Management Of The Silver Gull (Larus Novaehollandiae) In Melbourne, Australia, Ian D. Temby Aug 2000

Pieces Of Silver: Examples Of The Economic Impact And Management Of The Silver Gull (Larus Novaehollandiae) In Melbourne, Australia, Ian D. Temby

Human Conflicts with Wildlife: 2002 Symposium

Like a number of gull species, the silver gull Larus novaehollandiae has expanded its population in response to human food subsidy. The major anthropogenic food source is food waste at rubbish tips. Other sources of human food waste are also exploited. Many problems result from the activities of these birds, including human health and safety, economic impacts, and effects on the conservation of other species. My study examines aspects of the economic impacts of the silver gull on the human community of the Greater Melbourne Area comprising approximately 4065 km2 (1569 square miles). My data collection method involves identifying sites …


Behavioral Principles Governing Conditioned Food Aversions Based On Deception, Michael R. Conover Aug 1995

Behavioral Principles Governing Conditioned Food Aversions Based On Deception, Michael R. Conover

National Wildlife Research Center Repellents Conference 1995

We often are unable to reduce wildlife damage because of our inability to apply a repellent directly to the plant, animal, or item that needs protection. Conditioned food aversions based on deception (CFABD) is one method that can be used to extend protection to these items (hereafter called models). In CFABD, the model is not treated; instead mimics of the model are created and then treated with a chemical that will sicken, but not kill, the animal consuming them. This approach is a reverse form of Batesian mimicry; normally the models are poisonous and the mimics are innocuous. Yet, the …