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Full-Text Articles in Physical Sciences and Mathematics

Rodents In Agriculture: A Broad Perspective, Gary Witmer Jan 2022

Rodents In Agriculture: A Broad Perspective, Gary Witmer

USDA Wildlife Services: Staff Publications

The largest taxonomic group of mammals is rodents, with over 2200 species known around the world [1]. More recently, it was stated that over 2500 species exist [2]. Many species exist on all continents, with the exception of Antarctica. Rodents have adapted to all ecosystems of the world, including tundra, alpine, temperate forests, grasslands, arid regions, and aquatic systems. They provide many ecosystem functions, including soil aeration and mixing, seed and spore dispersal, vegetation succession, and being an important food source for predatory animals. Some species of rodents are even consumed by people in some parts of the world. Most …


Evaluating The Effects Of Mountain Beaver (Aplodontia Rufa) Management On Conifer Stocking In Western Oregon, Jimmy D. Taylor, Vanessa M. Petro Jan 2021

Evaluating The Effects Of Mountain Beaver (Aplodontia Rufa) Management On Conifer Stocking In Western Oregon, Jimmy D. Taylor, Vanessa M. Petro

USDA Wildlife Services: Staff Publications

Mountain beaver (Aplodontia rufa) is the most primitive rodent species in North America and is endemic to the Pacific Northwest, USA. Within their range, mountain beaver cause more conflict with conifer forest regeneration than any other vertebrate species. Most damage occurs as a result of clipping and browsing new seedlings, which reduces stocking density and delays stand development. An integrated approach using trapping and a registered toxicant (baiting) has been suggested as the most efficacious means to reduce seedling loss during stand initiation. We evaluated this management strategy in intensively managed conifer stands across two mountain ranges in …


Population Increases Of Large Birds In North America Pose Challenges For Aviation Safety, Richard A. Dolbeer Jan 2020

Population Increases Of Large Birds In North America Pose Challenges For Aviation Safety, Richard A. Dolbeer

USDA Wildlife Services: Staff Publications

There is a strong correlation between bird mass and the likelihood of aircraft damage during a bird–aircraft collision. Thus, the U.S. Federal Aviation Administration (FAA) has established airworthiness standards related to bird mass for engines, airframes, and windshields. Most standards use large (1.8 kg) and medium (1.1 kg) birds as benchmarks (the empennage and certain large turbofan engines use a 3.6-kg bird). There are 20 large (≥1.8 kg) and 16 medium (1.1–1.7 kg) bird species in North America with ≥20 strikes reported for civil aircraft (FAA National Wildlife Strike Database), 1990 to 2018. I analyzed the population changes of these …


The Changing Role Of Rodenticides And Their Alternatives In The Management Of Commensal Rodents, Gary Witmer Oct 2019

The Changing Role Of Rodenticides And Their Alternatives In The Management Of Commensal Rodents, Gary Witmer

USDA Wildlife Services: Staff Publications

Rodents cause substantial damage and losses of foodstuffs around the world. They also transmit many diseases to humans and livestock. While various methods are used to reduce damage caused by rodents, rodenticides remain an important tool in the toolbox. However, like all tools, rodenticides have advantages and disadvantages. Several considerations are shaping the future of rodenticide use, including manufacturing and registration costs, concern about toxicity levels and nontarget animal hazards, potential hazards to children, reduced effectiveness of some formulations, and humaneness to the targeted rodents. Many of these disadvantages apply to anticoagulant rodenticides, and their use is being more restricted …


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 …


Effectiveness Of Frightening Devices For Reducing Deer Damage In Cornfields, Jason M. Gilsdorf Aug 2002

Effectiveness Of Frightening Devices For Reducing Deer Damage In Cornfields, Jason M. Gilsdorf

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Damage Abatement And Compensation Programs As Incentives For Wildlife Management On Private Land, Jonathan K. Yoder Aug 2000

Damage Abatement And Compensation Programs As Incentives For Wildlife Management On Private Land, Jonathan K. Yoder

Human Conflicts with Wildlife: 2002 Symposium


Public damage abatement and compensation programs may be used to alter private incentives for damage abatement and habitat provision. A model is developed that explains the economic logic behind prevalent characteristics of public wildlife damage programs. The model is supported with an examination of a broad cross-section of wildlife agency policy and law. The model can be used by wildlife managers and policy makers as a conceptual framework for understanding the incentive effects of compensation and abatement policy.


Impacts Of House Mice On Crops In Australia - Costs And Damage, Peter R. Brown, Grant R. Singleton Aug 2000

Impacts Of House Mice On Crops In Australia - Costs And Damage, Peter R. Brown, Grant R. Singleton

Human Conflicts with Wildlife: 2002 Symposium

Rodents cause serious losses to crops in many different parts of the world. The house mouse (Mus domesticus, Schwarz and Schwarz 1943) is a serious pest to agriculture in Australia. The impacts of house mouse damage to crops in Australia were examined. Plagues of mice (>1,000 mice/ha) cause enormous economic and social stress to rural communities in Australia. The mouse plague in 1993/94 caused about US$60 million in damage to crops, intensive livestock industries, and rural communities. The impact of mouse plagues is generally well understood, but there is a dearth of knowledge about the relationship between …


Development Of A Model To Assess Rodent Control In Swine Facilities, Kurt C. Vercauteren, Scott E. Hygnstrom, Robert M. Timm, Robert M. Corrigan, John Beller, Larry L. Bitney, Michael C. Brumm, Daniel Meyer, Dallas R. Virchow, Robert W. Wills Aug 2000

Development Of A Model To Assess Rodent Control In Swine Facilities, Kurt C. Vercauteren, Scott E. Hygnstrom, Robert M. Timm, Robert M. Corrigan, John Beller, Larry L. Bitney, Michael C. Brumm, Daniel Meyer, Dallas R. Virchow, Robert W. Wills

Human Conflicts with Wildlife: 2002 Symposium

At the request, and with the support, of the National Pork Producers Council we are conducting a comprehensive economic analysis of rodent control in swine production facilities. The authors represent an interdisciplinary working group that has been assembled to identify all necessary input variables and values associated with rodent damage and control. The working group consists of specialists in swine production, facilities management, agricultural economics, swine health, rodent control, the pest management industry, systems modeling, and distance education. We incorporated data from the scientific literature and personal experience into an interactive STELLA systems model. The model generates benefit-cost analyses and …


The Economics Of Managing Belding’S Ground Squirrels In Alfalfa In Northeastern California, Desley A. Whisson, Steve B. Orloff, Donald L. Lancaster Aug 2000

The Economics Of Managing Belding’S Ground Squirrels In Alfalfa In Northeastern California, Desley A. Whisson, Steve B. Orloff, Donald L. Lancaster

Human Conflicts with Wildlife: 2002 Symposium

We used estimates of yield loss from 1995 to 1999 and the reported costs and effectiveness of available control methods to provide a basis for developing a cost-effective management strategy for Belding’s ground squirrels in alfalfa in northern California. Mean annual losses varied between US$110/ha and US$300/ha of alfalfa. Growers usually spend less than US$25/ha on control methods that are implemented haphazardly and provide poor control. We suggest that growers can afford to spend more on control methods such as burrow fumigation or exclusion fencing that previously have been viewed as being too expensive. Control efforts should be focused on …


Wildlife Impacts On Forest Resources, Dale L. Nolte, Mike Dykzeul Aug 2000

Wildlife Impacts On Forest Resources, Dale L. Nolte, Mike Dykzeul

Human Conflicts with Wildlife: 2002 Symposium

The negative impacts of wildlife on forest resources can be extensive. This paper provides some insight into the economic and environmental consequences of wildlife damage to forest resources and a brief overview of the damage inflicted by select wildlife species. Probably the most thorough measure of wildlife damage to forests in the Pacific Northwest was initiated in 1963 and 1964 by the Committee on Animal Damage Survey of the Western Forestry and Conservation Association. This study estimated that 30% of the tree seedlings planted would be damaged if no preventive practices were implemented; stocking rates on unprotected sites were 75% …


Recent Studies On Flavor Aversion Learning In Wildlife Damage Management, Russell F. Reidinger Jr. Aug 1995

Recent Studies On Flavor Aversion Learning In Wildlife Damage Management, Russell F. Reidinger Jr.

National Wildlife Research Center Repellents Conference 1995

Flavor aversion learning (FAL) occurs experimentally when a mammal is presented with a distinctive-flavored food followed by a postingestional illness. Birds may learn aversions to visual cues. Aversions follow a single pairing and may be robust. During the past decade, at least four directions were followed in evaluating FAL for managing wildlife damage: compounds already registered for use on crops such as herbicides, insecticides, or fungicides were tested for their abilities to also repel birds and small mammals from crops; naturally occurring compounds such as sucrose or charcoal were similarly evaluated; eggs were treated with different compounds in attempts to …


An Integrated Strategy To Decrease Eared Dove Damage In Sunflower Crops, Ethel N. Rodriguez, Richard L. Bruggers, Roger W. Bullard, Robert Cook Aug 1995

An Integrated Strategy To Decrease Eared Dove Damage In Sunflower Crops, Ethel N. Rodriguez, Richard L. Bruggers, Roger W. Bullard, Robert Cook

National Wildlife Research Center Repellents Conference 1995

Eared doves (Zenaida auriculata) damage mature sunflowers in Uruguay. Although repellents might be useful as a control method, durability and expense have discouraged their use. In the present report, we describe laboratory, aviary, and field research designed to evaluate methiocarb and calcium carbonate as durable, economical repellents. Calcium carbonate (CaCO3) was as effective as CaCO3 /methiocarb in combination in deterring consumption of sunflowers. Moreover, treating field borders with CaCO3 or the CaCO3 /methiocarb combination was as effective as treating the entire field for at least 12 days. This period is sufficiently long to …


The Influence Of Alfalfa Root Structure On Plains Pocket Gopher Damage And Behavior, Bruce A. Jasch Dec 1992

The Influence Of Alfalfa Root Structure On Plains Pocket Gopher Damage And Behavior, Bruce A. Jasch

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Evaluation Of Monofilament Lines To Prevent Damage By Birds, Danilo A. Aguero May 1990

Evaluation Of Monofilament Lines To Prevent Damage By Birds, Danilo A. Aguero

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


House Mouse Populations And Their Damage To Common Building Insulations, Daryl D. Fisher Dec 1984

House Mouse Populations And Their Damage To Common Building Insulations, Daryl D. Fisher

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Small Mammal Populations And Rodent Damage In Nebraska No-Tillage Crop Fields, Kent E. Holm Dec 1984

Small Mammal Populations And Rodent Damage In Nebraska No-Tillage Crop Fields, Kent E. Holm

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.