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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 …


High Speed Flight At Low Altitude: Hazard To Commercial Aviation ?, Paul F. Eschenfelder , Capt. Mar 2011

High Speed Flight At Low Altitude: Hazard To Commercial Aviation ?, Paul F. Eschenfelder , Capt.

Paul F. Eschenfelder

Commercial aircraft are capable of, and in fact, do, operate at high speed (>250 knots indicated airspeed [KIAS]) at low altitude (below 10,000’ above ground level) worldwide. Design, construction and certification standards for these aircraft were developed over 40 years ago. Since the development of these standards populations of large flocking birds have increased dramatically in many parts of the world. Yet neither design/construction standards nor operational practice have changed to reflect the new threat. Subsequent serious damage resulting from recent collisions indicates change is necessary. Since 2003, flight rules in Canada and the United States have been amended, …


Wildlife Damage Management (Wdm) In The Southern Utah Adc District, United States Department Of Agriculture, Animal And Plant Health Inspection Service, Animal Damage Control Jan 1989

Wildlife Damage Management (Wdm) In The Southern Utah Adc District, United States Department Of Agriculture, Animal And Plant Health Inspection Service, Animal Damage Control

All U.S. Government Documents (Utah Regional Depository)

Across the United States, wildlife habitat has been substantially changed as human populations expand and land is used for human needs. These human uses and needs often compete with wildlife which increases the potential for conflicting human/wildlife interactions. In addition, segments of the public strive for protection for all wildlife; this protection can create localized conflicts between human and wildlife activities.