Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

United States Department of Agriculture Wildlife Services: Staff Publications

Discipline
Keyword
Publication Year
File Type

Articles 1381 - 1410 of 1625

Full-Text Articles in Physical Sciences and Mathematics

Neotropical Frogs In Hawaii: Status And Management Options For An Unusual Introduced Pest, Earl W. Campbell Iii, Fred Kraus Feb 2002

Neotropical Frogs In Hawaii: Status And Management Options For An Unusual Introduced Pest, Earl W. Campbell Iii, Fred Kraus

United States Department of Agriculture Wildlife Services: Staff Publications

Two species of Neotropical frog, Eleutherodactylus coqui and E. planiroshir, have been introduced into the state of Hawaii via the horticulture trade. Since 1997 frog colonies within the state have rapidly spread from accidental and intentional causes, and frog abundance within colonies has grown rapidly. Colonies of these frogs are currently known from 262+ locations on the island of Hawaii, 45+ on Maui, 35+ on Oahu, and 2+ on Kauai Although these frogs were originally restricted to horticulture sites, they are now found in residential areas, resorts and hotels, and public lands. Within their native range, they may reach …

Go to article

Responses Of Blackbirds To Aerial Application Of Flight Control Bird Repellent To Ratoon Rice In Cameron Parish, Louisiana, M L. Avery, J. S. Humphrey, E. A. Tillman Feb 2002

Responses Of Blackbirds To Aerial Application Of Flight Control Bird Repellent To Ratoon Rice In Cameron Parish, Louisiana, M L. Avery, J. S. Humphrey, E. A. Tillman

United States Department of Agriculture Wildlife Services: Staff Publications

Blackbird damage to ripening rice is an economically important problem for many producers in Louisiana and elsewhere. Currently, management options for dealing with this problem are limited and generally ineffective. One possible option is the application of a chemical feeding deterrent. in October 1998, we tested the commercial bird repellent Flight Control, which has anthraquinone as its active repellent ingredient. Blackbird use of a 4-ha plot of ratoon rice treated with Flight Control at a rate of 18.7 L ha-I declined dramatically and birds stayed off the plot for 7 d postspray. These results corroborate those obtained in a similar …

Go to article

Understanding Avian Vision: The Key To Using Light In Bird Management, Bradley F. Blackwell Feb 2002

Understanding Avian Vision: The Key To Using Light In Bird Management, Bradley F. Blackwell

United States Department of Agriculture Wildlife Services: Staff Publications

Vision is a primary and highly developed sensory pathway in buds. Light, both diffuse and wavelength-specific (e.g., as produced by lasers) has recently been demonstrated as a potential means of effecting changes in timing and consistency of flock response to an approaching vehicle (simulating an aircraft) and as an avian dispersal method. However, in experiments to date, the effectiveness of light in eliciting an avoidance or dispersal response in birds has varied by species and context. To effectively use light in managing avian conflicts with humans, a better understanding of the complexities of avian retinal physiology relative to phototaxic responses …

Go to article

Civil Aircraft Collisions With Birds And Other Wildlife In Ohio, 1990-1999, Scott C. Barras, Sandra E. Wright Feb 2002

Civil Aircraft Collisions With Birds And Other Wildlife In Ohio, 1990-1999, Scott C. Barras, Sandra E. Wright

United States Department of Agriculture Wildlife Services: Staff Publications

Collisions between wildlife and aircraft (wildlife strikes) cost civil aviation more than $380 million annually in the US and pose a safety risk to flight personnel and passengers. We investigated wildlife strike trends and characteristics of strikes at airports in Ohio, 1990-1999, by analysis of data from the Federal Aviation Administration (FAA) National Wildlife Strike Database. Of 903 reported wildlife strikes with civil aircraft in Ohio, 98% were bird strikes and 2% involved mammals (primarily white-tailed deer [Odocoileus virginiana] and coyote [Canis latrans]). Reported wildlife strikes increased (P <0.01) from 39 in 1990 to 165 in 1999- Species groups most commonly involved in bird strikes were gulls (Larus spp., 135), raptors (Falconiformes and Strigiformes, 55), …

Go to article

Vegetation Management Approaches For Reducing Wildlife-Aircraft Collisions, Scott C. Barras, Thomas W. Seamans Feb 2002

Vegetation Management Approaches For Reducing Wildlife-Aircraft Collisions, Scott C. Barras, Thomas W. Seamans

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife-aircraft collisions (wildlife strikes) pose safety risks to aircraft and cost civil aviation over $390 million annually in the USA. We reviewed the results of prior studies to summarize the vegetation management techniques that have proven effective for wildlife strike reduction or have shown potential for achieving the same goal. Habitat components that may affect wildlife use of airports include food, cover, water, and loafing areas. Improperly managed natural and ornamental vegetation on airports can be important attractants for wildlife that pose strike hazards. However, effective vegetation management can reduce these hazards. Maintaining tall herbaceous vegetation may reduce the availability …

Go to article

Dispersing Vulture Roosts On Communication Towers, Michael L. Avery, John S. Humphrey, Eric A. Tillman, Kimberly O. Phares, Jane E. Hatcher Feb 2002

Dispersing Vulture Roosts On Communication Towers, Michael L. Avery, John S. Humphrey, Eric A. Tillman, Kimberly O. Phares, Jane E. Hatcher

United States Department of Agriculture Wildlife Services: Staff Publications

Communication towers provide attractive roost sites for Black (Coragyps atratus) and Turkey vultures (Cathartes aura). The birds’ roosting activity creates problems, however, for tower operators, nearby businesses, and adjacent homeowners. To alleviate these problems, at six sites in northern Florida we evaluated the effectiveness of suspending vulture carcasses or taxidermic effigies from towers to disperse vulture roosts. In each case, vulture numbers decreased immediately after installation of the stimulus, and roosts declined 93-100% within nine days. The effect was independent of the composition of the roost and occurred regardless of which vulture species was used as …

Go to article

Birds In Pest Management, M L. Avery Feb 2002

Birds In Pest Management, M L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

As human activity encroaches on wildlife habitats and natural food sources become increasingly scarce, it is no wonder that birds turn to habitats such as crop fields and aquaculture ponds. Where else can large flocks of birds find sufficient, nutritious, readily available food? Agricultural crops create ideal foraging sites for gregarious bird species, and virtually everything that humans grow or raise for food is subject to some level of bird damage. For most farmers, bird damage is a fact of life, but not a major concern. The unlucky few producers for whom depredations are severe, however, do incur substantial financial …

Go to article

Monk Parakeet Management At Electric Utility Facilities In South Florida, Michael L. Avery, Ellis C. Greiner, James R. Lindsay, James R. Newman, Stephen Pruett-Jones Feb 2002

Monk Parakeet Management At Electric Utility Facilities In South Florida, Michael L. Avery, Ellis C. Greiner, James R. Lindsay, James R. Newman, Stephen Pruett-Jones

United States Department of Agriculture Wildlife Services: Staff Publications

The monk parakeet (Myiopsiirta monachus) is native to South America but has become established in several locations throughout the United States through purposeful and accidental releases. The species is unique among parrots in that it is not a cavity-nester, but instead it builds a bulky nest structure of sticks. Often, in its native range and in the United States, the parakeet selects a electric utility structure as a nest site. Material from the nest then can cause short-circuits that result in damage to the utility structure and a subsequent power outage. In south Florida monk parakeet damage and …

Go to article

Behavioral And Ecological Considerations For Managing Bird Damage To Cultivated Fruit, Michael L. Avery Feb 2002

Behavioral And Ecological Considerations For Managing Bird Damage To Cultivated Fruit, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

Many bird species eat fruits and, likewise, many plant species are dependent on birds for the dispersal of seeds. Through cultivation and selective breeding, attributes of wild fruit have been changed to make fruit more palatable to humans. For example, cultivated species bear fruits that are often thinner-skinned. are more succulent, have fewer seeds and are easier to pick than non-cultivated species. These same changes, however, have also increased the attractiveness of fruit to avian consumers. Ecological relationships that have developed across evolutionary time between wild plants and frugivores become emphasized by the introduction of cultivated fruits that have been …

Go to article

Avian Repellents, Michael L. Avery Feb 2002

Avian Repellents, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

The use of repellents to protect crops from birds has a long history. Early European settlers in eastern North America observed that native Americans used an extract of Veratrum spp. to protect corn seeds from avian depredators: ‘‘Then when the starlings, crows, or other birds, pick up or pluck out the grains of corn, their heads grow delirious, and they fall, which so frightens the rest that they never venture on the field again. When those which have tasted the grains recover, they leave the field, and are no more tempted to visit it again’’ (1).

Repellents move birds from …

Go to article

Habitat Management Approaches For Reducing Wildlife Use Of Airfields, Scott C. Barras, Thomas W. Seamans Feb 2002

Habitat Management Approaches For Reducing Wildlife Use Of Airfields, Scott C. Barras, Thomas W. Seamans

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife-aircraft collisions (wildlife strikes) pose safety risks to aircraft and cost civil aviation over $390 million annually in the USA We reviewed published studies to summarize findings on habitat management techniques that have shown potential for wildlife strike reduction. Habitat components that may attract wildlife to airports include food, cover, water, and loafing areas. Although maintaining tall herbaceous vegetation on airfields may reduce the attractiveness of loafing and feeding sites for some species of birds such as gulls, this strategy may also increase cover and food resources for other hazardous species. Thus, optimum vegetation height management strategies require further research …

Go to article

Non-Lethal Radio Activated Guard For Deterring Wolf Depredation In Idaho: Summary And Call For Research, Stewart W. Breck, Rick Williamson, Carter Niemeyer, John A. Shivik Feb 2002

Non-Lethal Radio Activated Guard For Deterring Wolf Depredation In Idaho: Summary And Call For Research, Stewart W. Breck, Rick Williamson, Carter Niemeyer, John A. Shivik

United States Department of Agriculture Wildlife Services: Staff Publications

With the reestablishment of wolves in the western United States, managing adverse interactions between wolves and livestock is re-emerging as an issue for resource managers. Lethal control of wolves is often difficult to implement due to the constraints of the Endangered Species Act, predator population goals, and public disfavor for lethal control. In response to the need to manage wolf predation in a non-lethal manner, we developed and tested a behavior contingent system for disrupting predation events. The Avian Systems Model 9000 Frightening System, also called a Radio Activated Guard (RAG), is activated by signals from nearby wolf radio collars. …

Go to article

Population Increases Of Large Bird Species In Relation To Impact Standards For Aircraft Engines And Airframes, Richard A. Dolbeer Feb 2002

Population Increases Of Large Bird Species In Relation To Impact Standards For Aircraft Engines And Airframes, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

Bird-aircraft collisions (bird strikes) are an increasing safety and economic concern to the USA civil aviation industry, costing over $400 million each year. One approach to reducing risks associated with strikes is to require commercial aircraft components to meet certain standards of safe performance in the event of a bird strike. The Federal Aviation Administration has developed airworthiness standards for airframes, windshields and engines using a single 4-lb (1.82-kg) bird mass as the maximum that must be tested (with the exception of a single 8-lb bird for the empennage, 6-lb bird for certain mid-sized engines that may be developed in …

Go to article

Lasers As Non-Lethal Avian Repellents: Potential Applications In The Airport Environment, Bradley F. Blackwell, Glen E. Bernhardt, Jonathon D. Cepek, Richard A. Dolbeer Feb 2002

Lasers As Non-Lethal Avian Repellents: Potential Applications In The Airport Environment, Bradley F. Blackwell, Glen E. Bernhardt, Jonathon D. Cepek, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

Research conducted by the U.S. Department of Agriculture’s (USDA) National Wildlife Research Center (NWRC) indicates that low- to moderate-power, long-wavelength lasers (630- 650 nm) provide an effective means of dispersing some “problem” bird species under low-light conditions, while presenting no threat to the animal or the environment. The NWRC researchers tested the hypothesis that birds would avoid the beam or beam spot produced by a laser in low ambient light. In the format of controlled, replicated, 2-choice experiments with captive birds, Canada geese (Branta canadensis; 6 groups; 4 birds/group) exhibited extreme avoidance of laser beams over 80-minute periods, …

Go to article

A Comparison Of Potential Labor-Saving Sampling Methods For Assessing Large Mammal Damage In Corn, Richard . M. Engeman, Ray T. Sterner Jan 2002

A Comparison Of Potential Labor-Saving Sampling Methods For Assessing Large Mammal Damage In Corn, Richard . M. Engeman, Ray T. Sterner

United States Department of Agriculture Wildlife Services: Staff Publications

Accurate estimation of crop damage by wildlife often requires labor-intensive sampling procedures. Variable area transect (VAT) sampling has been identified as a potential labor-saving alternative to quadrat sampling. We fully enumerated all damaged corn plants in a field to assess accuracy of sampling by small quadrats 5m long by one or two row-widths, and by VAT sampling with searches from random starting points to the 3rd, 4th, 5th, and 6th damaged plant. Two widths for strip transects also were considered for VAT sampling: one and two crop rows. Two analytical formulae were considered for the VAT data. Thus, 18 estimates …

Go to article

An Economic Analysis Of Predator Removal Approaches For Protecting Marine Turtle Nests At Hobe Sound National Wildlife Refuge, Richard M. Engeman, Stephanie A. Shwiff, Bernice Constantin, Margo Stahl, Henry T. Smith Jan 2002

An Economic Analysis Of Predator Removal Approaches For Protecting Marine Turtle Nests At Hobe Sound National Wildlife Refuge, Richard M. Engeman, Stephanie A. Shwiff, Bernice Constantin, Margo Stahl, Henry T. Smith

United States Department of Agriculture Wildlife Services: Staff Publications

Hobe Sound National Wildlife Refuge (HSNWR) on Florida’s east coast provides undisturbed nesting habitat for three species of threatened or endangered marine turtles. Predation by raccoons and armadillos poses the greatest risk to turtle nests, and predator control has been identified as the most important management tool for enhancing nesting productivity. Recently, estimates of the number of nests that would have been lost in the 2000 nesting and incubation season were made using the results from four control approaches. These approaches were, in order of descending complexity: (1) refuge control enhanced by a one person-month contract with federal control specialists, …

Go to article

Monetary Valuation Methods For Economic Analysis Of The Benefit-Costs Of Protecting Rare Wildlife Species From Predators, Richard M. Engeman, Stephanie A. Shwiff, Henry T. Smith, Bernice Constantin Jan 2002

Monetary Valuation Methods For Economic Analysis Of The Benefit-Costs Of Protecting Rare Wildlife Species From Predators, Richard M. Engeman, Stephanie A. Shwiff, Henry T. Smith, Bernice Constantin

United States Department of Agriculture Wildlife Services: Staff Publications

Many threatened and endangered species are negatively impacted by predation. Management of the predators that are geographically and temporally in position to threaten species of concern can greatly aid in their conservation. However, decisions on management strategies are based within economic constraints, while the success of management actions is measured by wildlife resource improvement. Here, we review methods for applying monetary valuations for threatened and endangered species so that economic analyses of management actions can be used to help guide and evaluate management decisions. A variety of applied examples are provided to demonstrate the principles.

Go to article

Safety Of Brucella Abortus Strain Rb51 Vaccine In Non-Target Ungulates And Coyotes, Terry J. Kreeger, Thomas J. Deliberto, Steven C. Olsen, William H. Edwards, Walter E. Cook Jan 2002

Safety Of Brucella Abortus Strain Rb51 Vaccine In Non-Target Ungulates And Coyotes, Terry J. Kreeger, Thomas J. Deliberto, Steven C. Olsen, William H. Edwards, Walter E. Cook

United States Department of Agriculture Wildlife Services: Staff Publications

Brucellosis is endemic in free-ranging elk (Cervus elaphus) and bison (Bison bison) in the Greater Yellowstone Area (GYA; USA). It is possible that an oral brucellosis vaccine could be developed and disseminated in the GYA to reduce disease transmission. Should this occur, non-target species other than elk and bison may come in contact with the vaccine resulting in morbidity or mortality. To assess biosafety, bighorn sheep (Ovis canadensis; n=10), pronghorn (Antilocapra americana; n=9), mule deer (Odocoileus hemionus; n=11), moose (Alces alces shirasi; n=10), and …

Go to article

A Baiting System For Delivery Of An Oral Plague Vaccine To Black-Tailed Prairie Dogs, Terry E. Creekmore, Tonie E. Rocke, Jerry Hurley Jan 2002

A Baiting System For Delivery Of An Oral Plague Vaccine To Black-Tailed Prairie Dogs, Terry E. Creekmore, Tonie E. Rocke, Jerry Hurley

United States Department of Agriculture Wildlife Services: Staff Publications

Laboratory and field studies were conducted between July and October 1999 to identify bait preference, biomarker efficacy, and bait acceptance rates for delivering an oral plague vaccine to black-tailed prairie dogs (Cynomys ludovicianus). Twenty juvenile captive prairie dogs were offered alfalfa baits containing either alfalfa, alfalfa and 5% molasses, or alfalfa, 5% molasses and 4% salt. Based on the results of these trials we selected a bait containing alfalfa, 7% molasses, and 1% salt for field trials to determine bait acceptance rates by free-ranging animals. The biomarkers DuPont Blue dye, iophenoxic acid, and tetracycline hydrochloride were orally administered …

Go to article

Review Of Determination Of Organic Compounds In Soils, Sediments And Sludges By T. R. Crompton, John J. Johnston Jan 2002

Review Of Determination Of Organic Compounds In Soils, Sediments And Sludges By T. R. Crompton, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

T. R. Crompton has accomplished the Herculean task of summarizing the literature (up to 1998) for the determination of organic and organometallic substances in soils, aquatic, and marine sediments and sludge. Although previous books address the analysis of such compounds in water, this is the first book dedicated to the analysis of pollutants in soils, sediments, and sludges, matrices that typically contain a variety of interfering compounds and offer significant analytical challenges. Overall, the book is relatively easy to read; the “camera ready” manuscript produced by the author contains clear tables, figures, and font. Classes of compounds addressed in this …

Go to article

Quantification Of Plasma And Egg 4,4′ Dinitrocarbanilide (Dnc) Residues For The Efficient Development Of A Nicarbazin-Based Contraceptive For Pest Waterfowl, John J. Johnston, Walter M. Britton, Alexander Macdonald, Thomas M. Primus, Margaret J. Goodall, Christi A. Yoder, Lowell A. Miller, Kathleen A. Fagerstone Dec 2001

Quantification Of Plasma And Egg 4,4′ Dinitrocarbanilide (Dnc) Residues For The Efficient Development Of A Nicarbazin-Based Contraceptive For Pest Waterfowl, John J. Johnston, Walter M. Britton, Alexander Macdonald, Thomas M. Primus, Margaret J. Goodall, Christi A. Yoder, Lowell A. Miller, Kathleen A. Fagerstone

United States Department of Agriculture Wildlife Services: Staff Publications

Urbanization and associated landscaping has increased the abundance of year-round habitat for waterfowl, resulting in vegetation damage, loss of recreational activities, air transportation mishaps and health hazards. As part of a research program to develop socially acceptable techniques for management of pest bird populations, we are evaluating nicarbazin as a contraceptive in pest and surrogate avian species. As reproductive studies with Canada Geese (Branta canadensis) are tedious due to the difficulty of conducting controlled field studies and/or breeding geese in captivity, we evaluated the effects of oral nicarbazin administration on the production and hatchability of chicken studies are …

Go to article

Non-Target Impacts Of Strychnine Baiting To Reduce Pocket Gopher Populations On Forest Lands In The United States, Dale L. Nolte, Kimberly Wagner Nov 2001

Non-Target Impacts Of Strychnine Baiting To Reduce Pocket Gopher Populations On Forest Lands In The United States, Dale L. Nolte, Kimberly Wagner

United States Department of Agriculture Wildlife Services: Staff Publications

Reforestation efforts are often severely hindered on sites that contain high populations of pocket gophers (Thmmysspp). Strychnine baiting is a technique used to suppress pocket gopher populations until seedlings are established. Strychnine bait is applied below ground in pocket gopher burrows, however, primary and secondary hazards remain a concern. A study to assess primary hazards indicated that some individual rodents died post strychnine baiting but there was not a long-term negative impact on non-target rodent populations. Possible secondary hazards reflect the potential for predators OT scavengers to encounter poisoned pocket gophers. Concerns that pocket gophers may surface before …

Go to article

Novel Field Sampling Procedure For The Determination Of Methiocarb Residues In Surface Waters From Rice Fields, Thomas M. Primus, Dennis J. Kohler, Mike Avery, Pat Bolich, M.O. Way, John J. Johnston Nov 2001

Novel Field Sampling Procedure For The Determination Of Methiocarb Residues In Surface Waters From Rice Fields, Thomas M. Primus, Dennis J. Kohler, Mike Avery, Pat Bolich, M.O. Way, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

Methiocarb was extracted from surface water samples collected at experimental rice field sites in Louisiana and Texas. The sampling system consisted of a single-stage 90-mm Empore extraction disk unit equipped with a battery-powered vacuum pump. After extraction, the C-18 extraction disks were stored in an inert atmosphere at -10 °C and shipped overnight to the laboratory. The disks were extracted with methanol and the extracts analyzed by reversed-phase high-performance liquid chromatography with a methanol/water mobile phase. Methiocarb was detected by ultraviolet absorption at 223 nm and quantified with the use of calibration standards. Recoveries from control surface water samples fortified …

Go to article

Differential Responses Of Coyotes To Novel Stimuli In Familiar And Unfamiliar Settings, Charles E. Harris, Frederick F. Knowlton Nov 2001

Differential Responses Of Coyotes To Novel Stimuli In Familiar And Unfamiliar Settings, Charles E. Harris, Frederick F. Knowlton

United States Department of Agriculture Wildlife Services: Staff Publications

We studied behavioral responses of captive and wild coyotes (Canis latrans) toward novel objects and artificial scent stations to determine how they might respond to novel stimuli used in coyote management and research. When captive coyotes encountered novel stimuli in unfamiliar surroundings they showed little avoidance, while the same stimuli caused avoidance and neophobic reactions among coyotes when encountered in familiar surroundings. In the field phase of the study, radio-collared coyotes in southern Texas were intensively monitored in order to relate space-use patterns to the locations where these coyotes were exposed to artificial scent stations. Coyotes were more …

Go to article

The Demographic Response Of Bank-Dwelling Beavers To Flow Regulation: A Comparison On The Green And Yampa Rivers, Stewart W. Breck, Kenneth R. Wilson, Douglas C. Anderson Nov 2001

The Demographic Response Of Bank-Dwelling Beavers To Flow Regulation: A Comparison On The Green And Yampa Rivers, Stewart W. Breck, Kenneth R. Wilson, Douglas C. Anderson

United States Department of Agriculture Wildlife Services: Staff Publications

We assessed the effects of flow regulation on the demography of beavers (Castor canadensis) by comparing the density, home-range size, and body size of bank-dwelling beavers on two sixth-order alluvial river systems, the flow-regulated Green River and the free-flowing Yampa River, from 1997 to 2000. Flow regulation on the Green River has altered fluvial geomorphic processes, influencing the availability of willow and cottonwood, which, in turn, has influenced the demography of beavers. Beaver density was higher on the Green River (0.5–0.6 colonies per kilometer of river) than on the Yampa River (0.35 colonies per kilometer of river). Adult …

Go to article

Targeting Alphas Can Make Coyote Control More Effective And Socially Acceptable, Michael M. Jaeger, Karen M. Blejwas, Benjamin N. Sacks, Jennifer C.C. Neale, Mary M. Conner, Dale R. Mccullough Oct 2001

Targeting Alphas Can Make Coyote Control More Effective And Socially Acceptable, Michael M. Jaeger, Karen M. Blejwas, Benjamin N. Sacks, Jennifer C.C. Neale, Mary M. Conner, Dale R. Mccullough

United States Department of Agriculture Wildlife Services: Staff Publications

Research at the UC Hopland Research and Extension Center (HREC) has improved our understanding of how to reduce sheep depredation while minimizing the impact on coyotes. Analysis of a 14-year data set of HREC coyote-control efforts found that sheep depredation losses were not correlated with the number of coyotes removed in any of three time scales analyzed (yearly, seasonally and monthly) during corresponding intervals for the next 2 years. Field research using radiotelemetry to track coyotes supported and explained this finding. For example, in 1995, dominant “alphas” from four territories were associated with 89% of 74 coyote-killed lambs; “betas” and …

Go to article

Determination Of Cabergoline By Electrospray Ionization Tandem Mass Spectrometry: Picogram Detection Via Column Focusing Sample Introduction, Bruce A. Kimball, Thomas J. Deliberto, John J. Johnston Oct 2001

Determination Of Cabergoline By Electrospray Ionization Tandem Mass Spectrometry: Picogram Detection Via Column Focusing Sample Introduction, Bruce A. Kimball, Thomas J. Deliberto, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

An electrospray ionization tandem mass spectrometric method was developed for low-picogram detection of an ergot alkaloid, cabergoline, in coyote plasma extracts. Cabergoline is under investigation as an abortifacient in canid species. Central to the successful development of this method was the ability to introduce relatively large sample volumes into the mass spectrometer. This was achieved by focusing the analyte on a conventional high-performance liquid chromatography guard column prior to elution into the spectrometer. Volumes up to at least 900 μL could be injected onto the guard column using a 100% aqueous mobile phase. Cabergoline retained on the column was eluted …

Go to article

Evaluation Of Chemical Repellents For Reducing Crop Damage By Dickcissels In Venezuela, M. L. Avery, E. A. Tillman, C.C. Lauker Oct 2001

Evaluation Of Chemical Repellents For Reducing Crop Damage By Dickcissels In Venezuela, M. L. Avery, E. A. Tillman, C.C. Lauker

United States Department of Agriculture Wildlife Services: Staff Publications

In Venezuela, lethal control of wintering Dickcissels (Spiza americana) is considered a threat to the species survival. To help farmers protect their rice and sorghum crops from depredations by Dickcissels and to minimize the killing of large numbers of these birds, alternative non-lethal crop protection measures are needed. To that end, the responses of captive Dickcissels to three bird-repellent chemicals applied to rice seed were evaluated. In one-cup feeding trials, treatments of methiocarb (0.05% g g-1, applied as Mesurol® 75% wettable powder) and anthraquinone (0.5%, applied as Flight Control® ) reduced consumption of rice by 70% …

Go to article

Efficacy Of Wolfin To Repel Black-Tailed Deer, Dale L. Nolte, Kimberly K. Wagner Oct 2001

Efficacy Of Wolfin To Repel Black-Tailed Deer, Dale L. Nolte, Kimberly K. Wagner

United States Department of Agriculture Wildlife Services: Staff Publications

Deer and elk provide many desirable recreational opportunities but also can cause severe conflicts with humans. Excluding them from agricultural resources or from roadways is desirable, but fencing is expensive. A chemical barrier would offer a feasible alternative to reduce damage caused by deer. A series of three tests was conducted to assess whether black-tailed deer avoided areas treated with Wolfin, a synthetic predator odor. Wolfin failed to repel deer during any of these trials. We conclude that Wolfin, as applied within this study, is unlikely to reduce problems roused by free-ranging deer. West. J Appl. For. 16(4):182-186.

Go to article

Effects Of Trapping And Subsequent Short-Term Confinement Stress On Plasma Corticosterone In The Brown Treesnake (Boiga Irregularis) On Guam, Tom Mathies, Todd A. Felix, Valentine A. Lance Oct 2001

Effects Of Trapping And Subsequent Short-Term Confinement Stress On Plasma Corticosterone In The Brown Treesnake (Boiga Irregularis) On Guam, Tom Mathies, Todd A. Felix, Valentine A. Lance

United States Department of Agriculture Wildlife Services: Staff Publications

The effects of capture in a live trap and subsequent handling stress on plasma concentrations of corticosterone and other sex steroids were examined in wild male and female brown treesnakes (Boiga irregularis), an introduced species on Guam that has been implicated in the extirpation or decline of many of that island's vertebrate species. Males and females that spent 1 night in a trap had plasma levels of corticosterone about four and two times higher, respectively, than those of the respective free-ranging controls. Mean plasma levels of corticosterone of snakes that had spent 3 nights in a trap were …

Go to article

First Prev Next Last