208 research outputs found

    Fencing Methods to Reduce Deer Damage

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    The white-tailed deer (Odocoifeus virginianus) may cause more damage than any other wildlife species. Deer damage occurs in various forms including crop production, automobile accidents, aviation collisions on runways, disease transmission, degradation of natural ecosystems, and destruction of ornamental plantings. One practical method of controlling deer damage is through the use of exclusionary fencing. White-tailed deer are challenging to exclude as they are able to jump 3.0-m fences or fit through spaces \u3e 20 cm wide. Some deer problems (disease outbreaks, aircraft runways, and busy highways in deer migration corridors) may necessitate the installation of effective fencing no matter what the cost. Fences most often installed to control white-tailed deer damage include, but are not limited to, many varieties and types of wire mesh, plastic mesh, high-tensile steel wire, and electric fence. We have reviewed scientific literature on fencing to compare fence designs and methods to predict which are best suited for excluding deer under a variety of conditions. In situations where a nearly impenetrable, low maintenance, long-life fence is needed, a 3.0-3 64 m-high wire mesh fence is the best option. If complete exclusion is not a necessity and fence cost is an issue, a multi-strand, electrified, high-tensile steel wire fence may be sufficient. For seasonal protection, an affordable, easily installed, peanut butter fence may be adequate. Each fencing application will require consideration of different factors for determining the most appropriate fence, requiring a thorough comparison of available options to assist in the decision making process. The most important considerations for determining the best fence for a specific application include: level of protection desired from the fence, deer\u27s ability to penetrate different fence designs, motivation to penetrate a fence, costs associated with a fence, and possible negative effects of erecting a fence. Fencing may be only part of the answer to a deer damage issue. An integrated management approach may increase the overall efficacy of any individual damage reduction method, including fencing. With abundant white-tailed deer populations, recent disease outbreaks, increasing vehicle collisions, and increased urbanization, there is an increasing need for effective deer-damage management tools. There are many research needs in the area of wildlife exclusion. Few rigorous tests of the efficacy of different fence designs have been conducted. Efficacy levels of any specific fence design are difficult to establish due to the multitude of interacting variables determining how an animal will respond to a particular fence design. Most, if not all, of the scientific testing conducted to date has been directed at excluding animals. However, means of confining captive deer are also of importance

    Coyote-Activated Frightening Devices for Reducing Sheep Predation on Open Range

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    Domestic sheep ranching is an important agricultural industry in the United States and coyote (Canis latrans) depredation on lambs and ewes continues to challenge ranchers and agencies responsible for protecting sheep. Lethal methods used in controlling coyote depredation include aerial gunning, toxicants, trapping, and calling and shooting. Nonlethal methods include frightening devices, fences, livestock protection animals, and stringent husbandry practices. Ranchers and agencies responsible for controlling coyote depredation need frightening devices that are more effective than those currently available. We describe a field evaluation of 2 animal-activated frightening devices: an acoustic device and an acoustic device with a pop-up scarecrow and strobe light. We conducted the evaluation on open range in western Wyoming during the lambing period. No coyote kills were reported during 6,087 sheepnights at 3 sites protected by the acoustic devices or during 6,598 sheepnights at 3 sites protected by the acoustic scarecrow devices. Our devices show promise for reducing predation during the lambing period and merit further evaluation

    Evaluating wildlife-cattle contact rates to improve the understanding of dynamics of bovine tuberculosis transmission in Michigan, USA

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    Direct and indirect contacts among individuals drive transmission of infectious disease. When multiple interacting species are susceptible to the same pathogen, risk assessment must include all potential host species. Bovine tuberculosis (bTB) is an example of a disease that can be transmitted among several wildlife species and to cattle, although the potential role of several wildlife species in spillback to cattle remains unclear. To better understand the complex network of contacts and factors driving disease transmission, we fitted proximity logger collars to beef and dairy cattle (n = 37), white-tailed deer (Odocoileus virginianus; n=29), raccoon (Procyon lotor; n=53), and Virginia opossum (Didelphis virginiana; n=79) for 16 months in Michigan\u27s Lower Peninsula, USA. We determined inter- and intra-species direct and indirect contact rates. Data on indirect contact was calculated when collared animals visited stationary proximity loggers placed at cattle feed and water resources. Most contact between wildlife species and cattle was indirect, with the highest contact rates occurring between raccoons and cattle during summer and fall. Nearly all visits (\u3e99%) to cattle feed and water sources were by cattle, whereas visitation to stored cattle feed was dominated by deer and raccoon (46% and 38%, respectively). Our results suggest that indirect contact resulting from wildlife species visiting cattle-related resources could pose a risk of disease transmission to cattle and deserves continued attention with active mitigation

    Wildlife in Airport Environments: Chapter 5 Excluding Mammals from Airports

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    To ensure aircraft safety, it is critical to exclude large mammal species such as deer (Odocoileus spp.), feral swine (Sus scrota), and coyotes (Canis latrans) from airport environments, as well as to consider thoroughly and carefully all available management methods. Airports are often located on or adjacent to undeveloped land that provides habitat for various species large enough to pose a direct hazard to aircraft. Unoccupied expanses of forage near runways provide deer with sufficient incentive to leave cover and occupy airport lands. Associated risk and tragic collisions have ranked deer as the most hazardous wildlife group to aviation (Dolbeer et al. 2000, DeVault et al. 2011), necessitating the evaluation of appropriate means for excluding them and other medium to large mammals (Dolbeer et al. 2000). Exclusionary fences are the most effective, long-lasting, and straightforward tool for eliminating risks posed by deer and other large mammals at airports; however, these fences can be costly to purchase, erect, and maintain. Fences provide a visual sense of security for airport managers but also can accomplish a measurable and statistically significant level of protection to aircraft at airports (DeVault et al. 2008). A variety of evaluations and experiments have been conducted on fence options. Determining the most appropriate fence for a specific setting to accomplish a desired outcome can be challenging. When reviewing this body of literature, airport managers must consider the level of motivation among deer or other species in the experiment and relate it to their situation. In this chapter we review a variety of fence applications for excluding medium to large mammals and provide recommendations

    Persistent Spillback of Bovine Tuberculosis From White-Tailed Deer to Cattle in Michigan, USA: Status, Strategies, and Needs

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    Free-ranging white-tailed deer (Odocoileus virginianus) are believed to be a self-sustaining reservoir for bovine tuberculosis (bTB) in northeastern Lower Michigan, USA. Although a comprehensive control program is in place and on-farm mitigation strategies to curtail bTB transmission between cattle and deer have been implemented for over a decade, cattle and deer continue to become infected with the disease. Thus, renewed motivation to eradicate bTB is needed if that is truly the goal. Recurrent detection of bTB in cattle in the region is of mounting concern for state and federal agricultural agencies, producers, and wildlife managers. Current on-farm mitigation efforts include fencing and refined cattle feeding and watering practices. Liberal removal of antlerless deer through hunter harvest and disease control permits (DCPs) issued to cattle producers and agency sharp shooters have also been ongoing. Although these strategies have merit and efforts to reduce prevalence in deer and occurrence of positive farms are elevated, additional actions are needed. Heightened management actions to combat bTB in deer could include deer vaccination programs, strategic habitat manipulations to redistribute deer from farms, and precision removal of deer in proximity to high-risk farms. Foundational research to address development and delivery of vaccine to free-ranging deer is complete. Strategic management and habitat manipulation could reduce and disperse local concentrations of deer while better meeting wildlife, forestry, and agricultural goals. The responses of local deer populations to targeted removal of individuals are generally understood and there is potential to reduce deer activity around agricultural operations while allowing them to persist nearby on natural foods. We summarize the history and progress to date, discuss the realized merit of novel management strategies, and suggest options to rid deer and cattle in Michigan of bTB

    Dynamic Evocation of Hand Action Representations During Sentence Comprehension

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    This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. When listening to a sentence describing an interaction with a manipulable object, understanding the actor’s intentions is shown to have a striking influence on action representations evoked during comprehension. Subjects performed a cued reach and grasp response while listening to a context sentence. Responses were primed when they were consistent with the proximal intention of an actor (“John lifted the cell phone...”), but this effect was evanescent and appeared only when sentences mentioned the proximal intention first. When the sentence structure was changed to mention the distal intention first (“To clear the shelf...”), priming effects were no longer context specific and actions pertaining to the function of an object were clearly favored. These results are not compatible with a straightforward mental-simulation account of sentence comprehension but instead reflect a hierarchy of intentions distinguishing how and why actions are performed

    Evaluating wildlife-cattle contact rates to improve the understanding of dynamics of bovine tuberculosis transmission in Michigan, USA

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    Direct and indirect contacts among individuals drive transmission of infectious disease. When multiple interacting species are susceptible to the same pathogen, risk assessment must include all potential host species. Bovine tuberculosis (bTB) is an example of a disease that can be transmitted among several wildlife species and to cattle, although the potential role of several wildlife species in spillback to cattle remains unclear. To better understand the complex network of contacts and factors driving disease transmission, we fitted proximity logger collars to beef and dairy cattle (n = 37), white-tailed deer (Odocoileus virginianus; n=29), raccoon (Procyon lotor; n=53), and Virginia opossum (Didelphis virginiana; n=79) for 16 months in Michigan\u27s Lower Peninsula, USA. We determined inter- and intra-species direct and indirect contact rates. Data on indirect contact was calculated when collared animals visited stationary proximity loggers placed at cattle feed and water resources. Most contact between wildlife species and cattle was indirect, with the highest contact rates occurring between raccoons and cattle during summer and fall. Nearly all visits (\u3e99%) to cattle feed and water sources were by cattle, whereas visitation to stored cattle feed was dominated by deer and raccoon (46% and 38%, respectively). Our results suggest that indirect contact resulting from wildlife species visiting cattle-related resources could pose a risk of disease transmission to cattle and deserves continued attention with active mitigation

    Petition for a Writ of Certiorari to the United States Court of Appeals for the Ninth Circuit, Jensen v. EXC, Inc.

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    The petitioners argue: 1) Supervisory Review is Needed Because the District Court and the Ninth Circuit Automatically Aligned U.S. Highway 160 with Alienated, Non-Indian Fee Land, Ignoring this Court’s Context-Specific, Multifactor Methodology for Determining the Status of Reservation Roadways for Tribal Jurisdictional Purposes. 2) Supervisory Review is Also Necessary Because Both Lower Courts Refused to Apply Supreme Court Precedents Governing Whether an Indian Tribe Retains Treaty-Based Authority over the Conduct of Nonmembers on a Tribe’s Reservation, Effecting an Impermissible Judicial Abrogation of the Navajo Nation’s Congressionally Confirmed, Treaty-Based Jurisdiction in This Case. 3) Supervisory Review is Further Needed Because Both Lower Courts’ Denial of the Navajo Nation’s Retained Inherent Sovereignty over the Tour Bus/Auto Collision Conflicts with This Court’s Precedents for Proper Application of the Montana Exceptions

    A Simulation Model for Determining Cost-Effectiveness of Fences for Reducing Deer Damage

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    The installation of fences to protect agricultural products, natural resources, or other areas from deer (Odocoileus spp.) can be expensive and potential benefits of fencing are difficult to quantify. A rational method is needed to help evaluate whether fencing can be cost-effective and which fence designs will be optimal for particular applications. We describe an interactive, dynamic simulation model that conducts economic analyses and predicts economic benefit associated with fences for crops relative to area and perimeter of protected plot, value of crop, percentage of crop damaged by deer annually prior to fencing, efficacy of fence, and costs of fence materials and labor. Users of the model can easily adjust these variables to fit their individual situations and needs. By running a series of simulations, model users can answer questions related directly to fence efficacy and cost-effectiveness

    Nuclear Thermal Rocket Simulation in NPSS

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    Four nuclear thermal rocket (NTR) models have been created in the Numerical Propulsion System Simulation (NPSS) framework. The models are divided into two categories. One set is based upon the ZrC-graphite composite fuel element and tie tube-style reactor developed during the Nuclear Engine for Rocket Vehicle Application (NERVA) project in the late 1960s and early 1970s. The other reactor set is based upon a W-UO2 ceramic- metallic (CERMET) fuel element. Within each category, a small and a large thrust engine are modeled. The small engine models utilize RL-10 turbomachinery performance maps and have a thrust of approximately 33.4 kN (7,500 lbf ). The large engine models utilize scaled RL-60 turbomachinery performance maps and have a thrust of approximately 111.2 kN (25,000 lbf ). Power deposition profiles for each reactor were obtained from a detailed Monte Carlo N-Particle (MCNP5) model of the reactor cores. Performance factors such as thermodynamic state points, thrust, specific impulse, reactor power level, and maximum fuel temperature are analyzed for each engine design
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