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United States Department of Agriculture Wildlife Services: Staff Publications

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Articles 1441 - 1470 of 1529

Full-Text Articles in Physical Sciences and Mathematics

The Feasibility Of Controlling The Brown Treesnake In Small Plots, Gordon H. Rodda, Thomas H. Fritts, Earl W. Campbell Iii Apr 1999

The Feasibility Of Controlling The Brown Treesnake In Small Plots, Gordon H. Rodda, Thomas H. Fritts, Earl W. Campbell Iii

United States Department of Agriculture Wildlife Services: Staff Publications

There is an urgent need to provide snake-free or snake-reduced habitats for the wildlife species on Guam that have declined or disappeared as a result of predation by the Brown Treesnake, Boiga irregularis (Savidge, 1987; Fritts, 1988; Rodda and Fritts, 1992; Rodda et al., this volume, Chap. 2). At present, we know of no practical techniques for reducing or eradicating the snake throughout Guam, a densely populated island of 54,100 ha. Conserving native wildlife and reducing the incidences of snakes boarding ship and aircraft may not require the elimination of snakes from the entire island, however. Elimination of snakes from …

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An Overview Of The Biology Of The Brown Treesnake* (Boiga Irregularis), A Costly Introduced Pest On Pacific Islands, Gordon H. Rodda, Thomas H. Fritts, Michael J. Mccoid, Earl W. Campbell Iii Apr 1999

An Overview Of The Biology Of The Brown Treesnake* (Boiga Irregularis), A Costly Introduced Pest On Pacific Islands, Gordon H. Rodda, Thomas H. Fritts, Michael J. Mccoid, Earl W. Campbell Iii

United States Department of Agriculture Wildlife Services: Staff Publications

The 20-30 species of the genus Boiga (Colubridae, Boiginae) range from tropical Africa through southern Asia to Melanesia and Australia (Leviton, 1968). Collectively, they are known as catsnakes, mangrove snakes, or treesnakes (Obst et al., 1988; Greene, 1989). The common name "catsnakes" is sometimes used for snakes in the genus Telescopus as well (Obst et 1, 1988).

Members of the genus Boiga are nocturnal, oviparous, opisthoglyphic, euryphagic, and slender; they have vertical elliptical pupils (thus “cat” snakes) set in large eyes, and short, blunt heads that are noticeably larger than their necks. With one exception they are arboreal or semiarboreal …

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Candidate Repellents, Oral And Dermal Toxicants, And Fumigants For Brown Treesnake Control, Peter J. Savarie, Richard L. Bruggers Mar 1999

Candidate Repellents, Oral And Dermal Toxicants, And Fumigants For Brown Treesnake Control, Peter J. Savarie, Richard L. Bruggers

United States Department of Agriculture Wildlife Services: Staff Publications

The information presented in this chapter was obtained primarily from two computerized literature searches conducted on the Dialog System (Dialog Information Services, Inc.; Palo Alto, Calif.), which covers a wide variety of topics including medicine, environmental sciences, agriculture, and biology. The key word in the first search was the scientific name of the Brown Treesnake, Boiga irregularis. The key words in the second search were repellent, fumigant, toxicant, or control (or any variations of these words) together with the word snake or snakes. In contrast to the research and development of vertebrate pest control agents for rodents …

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Methods For The Diagnosis Of Acute 3-Chloro-P-Toluidine Hydrochloride Poisoning In Birds And The Estimation Of Secondary Hazards To Wildlife, John J. Johnston, Daniel B. Hurlbut, Michael L. Avery, Jack C. Rhyan Mar 1999

Methods For The Diagnosis Of Acute 3-Chloro-P-Toluidine Hydrochloride Poisoning In Birds And The Estimation Of Secondary Hazards To Wildlife, John J. Johnston, Daniel B. Hurlbut, Michael L. Avery, Jack C. Rhyan

United States Department of Agriculture Wildlife Services: Staff Publications

Female boat-tailed grackles poisoned with 3-chloro-p-toluidine hydrochloride (CPTH) were analyzed by necropsy and gas chromatography–mass spectrometry (GC-MS). The necropsies identified the presence of a white precipitate in the pericardium, which had been previously reported as a characteristic of CPTH-exposed birds. The GC-MS method, which utilized deuterated CPTH as a surrogate, quantified CPTH residues in the breast tissue and gastrointestinal tract of CPTH-exposed birds. Comparison of these techniques indicated that the GC-MS method was more accurate for assessing CPTH poisoning in birds. Regression analyses of consumption versus residue data indicated that the sum of breast and gastrointestinal residues can …

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United States Patent: Naturally-Odoriferous Animal Repellent, James Russell Mason, Richard Albert Dolbeer, George Preti Mar 1999

United States Patent: Naturally-Odoriferous Animal Repellent, James Russell Mason, Richard Albert Dolbeer, George Preti

United States Department of Agriculture Wildlife Services: Staff Publications

Certain volatile compounds naturally present in herring gull eggs are effective for repelling animals and birds, particularly canids, from the locus to which such compounds are applied. More particularly, the volatile compounds which are effective animal repellents include compounds exhibiting mint-like odors such as the compounds pulegone and piperitone. The invention relates to methods of using these compounds to repel animals, and to repellent compositions comprising effective repellent amounts of such compounds.

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Field Evaluation Of Radiotransmitters For Northern Pocket Gophers, Gary W. Witmer, Michael Pipas Mar 1999

Field Evaluation Of Radiotransmitters For Northern Pocket Gophers, Gary W. Witmer, Michael Pipas

United States Department of Agriculture Wildlife Services: Staff Publications

A field study was conducted in northern Idaho from June to November 1995 to evaluate the design and functional aspects of four types of Radio-transmitters for use on northern pocket gophers (Thomomys talpoides) as well as the effects of the transmitters on behavior of the animals. Twenty-five of 46 northern pocket gophers were fitted in the field with one of three models of radio-collars (AVM, NWRC, and Holohil), nine received Wildlife Materials abdominal implant transmitters (surgery conducted off-site), and 12 without transmitters served as controls. Study animals were relocated every second to fourth day until the end of …

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Alpha-Chloralose Immobilization Of Rock Doves In Ohio, Jerrold L. Belant, Thomas W. Seamans Jan 1999

Alpha-Chloralose Immobilization Of Rock Doves In Ohio, Jerrold L. Belant, Thomas W. Seamans

United States Department of Agriculture Wildlife Services: Staff Publications

To improve capture efficacy of rock doves (Columba livia) in nuisance situations, we reevaluated the effectiveness of three dosages (60, 120 and 180 mg/kg) of alpha-chloralose (AC). Responses to immobilization using 180 mg/kg AC also were compared in rock doves deprived of food for 16 hr and not food deprived. Mean (±SE) time to first effects (33 ± 2 min) and mean time to capture (94 ± 5 min) were significantly less for rock doves receiving 180 mg/kg than for rock doves receiving lower dosages (≥53 ± 3 min and ≥153 ± 17 min, respectively). Ten, 10, and …

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Quantitation Of Pyrethrum Residues In Brown Tree Snakes, John J. Johnston, Carol A. Furcolow, Stephanie A. Volz, Richard E. Mauldin, Thomas M. Primus, Peter J. Savarie, Joe E. Brooks Jan 1999

Quantitation Of Pyrethrum Residues In Brown Tree Snakes, John J. Johnston, Carol A. Furcolow, Stephanie A. Volz, Richard E. Mauldin, Thomas M. Primus, Peter J. Savarie, Joe E. Brooks

United States Department of Agriculture Wildlife Services: Staff Publications

A reversed-phase solid-phase extraction–gas chromatography (SPE–GC)–electron capture detection method is developed to quantitate individual rethrin residues in pyrethrum-exposed brown tree snakes. Aliquots (6 g) of homogenized snake tissue are extracted with 10 mL acetonitrile. The rethrins are recovered from the acetonitrile extract and concentrated using C8 SPE. The rethrins are eluted from the SPE column with pentane, evaporated to near dryness, and reconstituted to 1 mL with 1-propanol. Individual rethrins are quantitated using GC analysis of the 1-propanol solution. Method limits of detection for rethrins range from 0.63 to 6.51 ng/g. The mean recovery for all rethrins is 70.8% …

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Demonstration Of Tritrichomonas Foetus In The External Genitalia And Of Specific Antibodies In Preputial Secretions Of Naturally Infected Bulls, J. C. Rhyan, K. L. Wilson, B. Wagner, M. L. Anderson, R. H. Bondurant, D. E. Burgess, G. K. Mutwiri, L. B. Corbeil Jan 1999

Demonstration Of Tritrichomonas Foetus In The External Genitalia And Of Specific Antibodies In Preputial Secretions Of Naturally Infected Bulls, J. C. Rhyan, K. L. Wilson, B. Wagner, M. L. Anderson, R. H. Bondurant, D. E. Burgess, G. K. Mutwiri, L. B. Corbeil

United States Department of Agriculture Wildlife Services: Staff Publications

Portions of penis and prepuce were collected from 24 bulls with current or recent Tritrichomonas foetus infection. Epididymides were collected from seven of the bulls, and seminal vesicles and prostate were collected from four. Following immunohistochemical staining with two monoclonal antibodies (34.7C4.4 and TF1.15) prepared against T. foetus surface antigens, trichomonads were identified in sections from 15 of the bulls. Organisms were most often located in penile crypts in the midshaft and caudal regions and less often in preputial crypts. Trichomonads were not observed in sections from other genitalia or in subepithelial tissue. T. foetus antigen, however, was present in …

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Changes In Early Winter Abundance Of Four Gull (Larus) Species On Western Lake Erie, 1951-1995, Laura A. Tyson, Richard A. Dolbeer, Jerrod L. Belant Jan 1999

Changes In Early Winter Abundance Of Four Gull (Larus) Species On Western Lake Erie, 1951-1995, Laura A. Tyson, Richard A. Dolbeer, Jerrod L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Many gulls (Larus spp.) that nest on and north of the Great Lakes concentrate along the south shore of western Lake Erie in early winter. Monitoring population trends of these gulls is important because of increasing conflicts between gulls and humans. We used data from four Christmas Bird Count locations to examine population trends of four gull species on western Lake Erie during nine 5-year periods, 1951-1995. Overall, ring-billed gulls (Z. delawarensis} were the dominant species (59% of gulls counted) followed by herring (Z. argentatus, 20%), Bonaparte's (Z. Philadelphia, 18%) and great blackbacked (Z. marinus, 0.2%) gulls. Ring-billed gulls displayed …

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Ontogenetic Shifts In Canion Attractiveness To Brown Tree Snakes (Boiga Irregularis), John A. Shivik, Larry Clark Jan 1999

Ontogenetic Shifts In Canion Attractiveness To Brown Tree Snakes (Boiga Irregularis), John A. Shivik, Larry Clark

United States Department of Agriculture Wildlife Services: Staff Publications

The brown tree snake (Boiga irregularis) is a nocturnal, primarily arboreal, rear-fanged colubrid native to parts of Australasia (Savidge, 1987; Greene, 1989). Throughout their range, brown tree snakes eat a variety of prey including lizards, rats, and birds (Greene, 1989; Shine, 1991; Rodda, 1992; Rodda et al., in press). Brown tree snakes on Guam have a wide diet consisting mainly of lizards and lizard eggs, but a variety of other items were found in snake stomachs, including odd items such as cooked spareribs (Savidge, 1988). Savidge (1988) noted an ontogenetic shift in Guam brown tree snake diets; small …

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Pre-Baiting For Increased Acceptance Of Zinc Phosphide Baits By Voles: An Assessment Technique, Ray Sterner Jan 1999

Pre-Baiting For Increased Acceptance Of Zinc Phosphide Baits By Voles: An Assessment Technique, Ray Sterner

United States Department of Agriculture Wildlife Services: Staff Publications

During a product-performance test of 2% zinc phosphide (Zn3P2) steam-rolled-oat groats (11.2 kg ha-1) to control voles (Microtus spp) in alfalfa (Medicago sativa), randomly located, brushed-dirt plots were used to assess broadcast distribution and remova/acceptance of placebo particles. Results showed that the Spyker® Model-75 Spreaders were calibrated adequately, with placebo baits broadcast uniformly onto plots [x ± SD = 3.5 (±2.7) groats 930 cmp-1]. Acceptance of the placebos by voles increased rapidly - 28% and 60% by 24h and 48h post-broadcast, respectively. Analyses of variance confirmed the uniformity (non-significance) …

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Capsicum-Laden Soils Decrease Contact Time By Northern Pocket Gophers, Ray T. Sterner, Kelly Hollenbeck, Stephen Shumake Jan 1999

Capsicum-Laden Soils Decrease Contact Time By Northern Pocket Gophers, Ray T. Sterner, Kelly Hollenbeck, Stephen Shumake

United States Department of Agriculture Wildlife Services: Staff Publications

Fossorial rodents damage lawns/water impoundments/ crops. We conducted a two-choice, parametric-type study to determine the effects of capsicum-oleoresin/soil mixtures (0.00, 0.75, 1.50, and 2.25%) upon soil-contact, soil-digging, and pelage-grooming behaviors in northern pocket gophers (Thomomys talpoides). In 3 alternate-day (1-h/day) exposures to ≥1.50% capsicum-oleoresin soil mixtures, gophers decreased mean soil contact time by 46% relative to placebo-exposed animals. Grooming time yielded a concentration x trial interaction that showed intense grooming by capsicum-exposed animals during trial 1, with "convergence" of times to near those of the "placebos" (0.00% capsicum oleoresin) by trial 3. The significant decrease in grooming activity …

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Trapping Considerations For The Fossorial Pocket Gopher, Gary W. Witmer, Rex Marsh, George Matschke Jan 1999

Trapping Considerations For The Fossorial Pocket Gopher, Gary W. Witmer, Rex Marsh, George Matschke

United States Department of Agriculture Wildlife Services: Staff Publications

Fossorial mammals such as the pocket gopher (Thomomys spp.) are well adapted to life in an underground closed burrow system. These animals can have considerable influence on ecosystems and can cause significant damage to agricultural crops, forest resources, and field machinery. The research and management of pocket gopher populations poses many challenges to land managers and research biologists. Both live-trapping for research purposes and kill trapping for control purposes are important tools for working with pocket gophers. Trapping can be an effective and efficient tool if the proper traps are used and trappers are trained to place traps properly …

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Impact Of Snowfall On The Utah Preventive Aerial Hunting Program, Kimberly K . Wagner, Michael R. Conover Jan 1999

Impact Of Snowfall On The Utah Preventive Aerial Hunting Program, Kimberly K . Wagner, Michael R. Conover

United States Department of Agriculture Wildlife Services: Staff Publications

Aerial hunting is one of the tools used by wildlife managers to reduce predation by coyotes (Canis latrans) on livestock and wildlife (Guthery and Beasom 1977, Sterner and Schumake 1978, Stout 1982. Smith et al. 1986). In research conducted by Wagner and Conover (1999), areas with preventive aerial hunting had fewer confirmed and estimated lamb losses to coyote predation and required significantly fewer hours of additional corrective predation management than areas without aerial hunting. Aerial hunting is perceived to be especially valuable for large areas and areas with rough terrain and limited access (United States Department of the …

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Effective Of Preventive Coyote Hunting On Sheep Losses To Coyote Predation, Kimberly Wagner, Michael Conover Jan 1999

Effective Of Preventive Coyote Hunting On Sheep Losses To Coyote Predation, Kimberly Wagner, Michael Conover

United States Department of Agriculture Wildlife Services: Staff Publications

Aerial hunting is commonly used by agriculture agencies in the Intermountain West to reduce coyote (Canis latrans) predation on domestic sheep. We assessed the effect of aerial hunting of coyotes on sheep losses to coyotes, and the need for corrective predation management (hours of work, device nights) on the same pastures when sheep arrived for the subsequent summer grazing season (3-6 months after aerial hunting). Comparisons were made between paired pastures with (treated) and without (untreated) winter aerial hunting from helicopters. Average (x ± SE) pasture size was 45.2 ± 14.1 km2 (n = 21) for treated …

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Use Of Netted Cage Traps For Capturing White-Tailed Deer, Kurt C. Vercauteren, Jeff Beringer, Scott E. Hygnstrom Jan 1999

Use Of Netted Cage Traps For Capturing White-Tailed Deer, Kurt C. Vercauteren, Jeff Beringer, Scott E. Hygnstrom

United States Department of Agriculture Wildlife Services: Staff Publications

The safe and humane live capture of deer may be an important component of management and research projects. Growing populations of white-tailed deer (Odocoileus virginianus) in both urban and agricultural settings often conflict with local human interests and present challenges to natural resource managers. Netted cage traps can be an important tool when managing deer populations where traditional control methods may not be appropriate or acceptable. Netted cage traps can also be used by researchers to acquire deer for marking, measurements, or other non-lethal purposes. We discuss the design of netted cage traps, trapping techniques, and the handling …

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Nightly And Seasonal Movements Of Boiga Irregularis On Guam, Mark Tobin, Robert Sugihara, Patricia Pochop, Michael Linnell Jan 1999

Nightly And Seasonal Movements Of Boiga Irregularis On Guam, Mark Tobin, Robert Sugihara, Patricia Pochop, Michael Linnell

United States Department of Agriculture Wildlife Services: Staff Publications

Brown tree snakes (Boiga irregularis, BTS), inadvertently introduced to the island of Guam shortly after World War II, have had catastrophic effects on the native fauna of this U.S. territory. We used radio-telemetry to monitor daytime refugia and nightly movements of 60 BTS (30 during each of two seasonal periods) to determine the extent of nightly, weekly, and monthly movements. Eighty-three percent of subadult daytime sightings were in trees, compared to only 49% of adult daytime sightings. Most measures of movement did not vary with seasonal period, sex, or age class. BTS moved an average of 64 m …

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Repellents To Reduce Cable Gnawing By Northern Pocket Gophers, Stephen A. Shumake, Ray T. Sterner, Stanley E. Gaddis Jan 1999

Repellents To Reduce Cable Gnawing By Northern Pocket Gophers, Stephen A. Shumake, Ray T. Sterner, Stanley E. Gaddis

United States Department of Agriculture Wildlife Services: Staff Publications

There is a continuing need to develop improved repellent formulations to protect buried cable installations from damage by problem wildlife. We evaluated 2.0% mass/mass levels of capsaicin and denatonium benzoate in a polybutene carrier material (Indopol®) and an aboveground, rodent-deer plastic mesh barrier (Vexar®) for reducing gnawing by northern pocket gophers (Thomomys talpoides) on communications cable (RG-8U). When treatments were applied as surface coatings, neither capsaicin nor denatonium samples were lower (P > 0.05) in measnres of cable damage compared to control (Indopol® alone) or samples treated with Vexar® plastic mesh. When the test was repeated with a new …

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United States Patent: Lime Feeding Repellent, Jerrold L. Belant, Richard A. Dolbeer Aug 1998

United States Patent: Lime Feeding Repellent, Jerrold L. Belant, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

Application of lime at a rate of 500 to 1500 kg/ha to plots desired to be protected from damage by avian and mammalian feeders has been shown to be quite effective. The lime may be administered to the plots in any form. Use of either powder or slurry form is preferred.

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Optimization Of Variable Area Transect Sampling Using Monte Carlo Simulation, Richard M. Engeman, Robert T. Sugihara Jul 1998

Optimization Of Variable Area Transect Sampling Using Monte Carlo Simulation, Richard M. Engeman, Robert T. Sugihara

United States Department of Agriculture Wildlife Services: Staff Publications

An extensive simulation study was conducted to optimize the number, r, of population members to be encountered from each random starting point in variable area transect (VAT) sampling. The quality of estimation provided by the original calculation formula presented by K. R. Parker in 1979 was compared to another formula that was a Morisita analog intended to reduce bias when sampling aggregated populations. Monte Carlo simulations covered 64 combinations of four spatial patterns, four sample sizes, and four densities. Values of r from 3 through 10 were considered in each case. Relative root mean squared error was used as …

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Epidemic Leptospirosis Associated With Pulmonary Hemorrhage—Nicaragua, 1995, Rosalie T. Trevejo, José G. Rigau-Pérez, David A. Ashford, Emily M. Mcclure, Carlos Jarquín-González, Juan J. Amador, José O. De Los Reyes, Alcides Gonzalez, Sherif R. Zaki, Wun-Ju Shieh, Robert G. Mclean, Roger S. Nasci, Robbin S. Weyant, Carole A. Bolin, Sandra L. Bragg, Bradley A. Perkins, Richard A. Spiegel Jun 1998

Epidemic Leptospirosis Associated With Pulmonary Hemorrhage—Nicaragua, 1995, Rosalie T. Trevejo, José G. Rigau-Pérez, David A. Ashford, Emily M. Mcclure, Carlos Jarquín-González, Juan J. Amador, José O. De Los Reyes, Alcides Gonzalez, Sherif R. Zaki, Wun-Ju Shieh, Robert G. Mclean, Roger S. Nasci, Robbin S. Weyant, Carole A. Bolin, Sandra L. Bragg, Bradley A. Perkins, Richard A. Spiegel

United States Department of Agriculture Wildlife Services: Staff Publications

In October 1995, epidemic “hemorrhagic fever,” without jaundice or renal manifestations, was reported in rural Nicaragua following heavy flooding; 2259 residents were evaluated for nonmalarial febrile illnesses (cumulative incidence, 6.1%) and 15 (0.7%) died with pulmonary hemorrhage. A case-control study found that case-patients were more likely than controls to have ever walked in creeks (matched odds ratio [MOR], 15.0; 95% confidence interval [CI], 1.7–132.3), have household rodents (MOR, 10.4; 95% CI, 1.1–97.1), or own dogs with titers ≥ 400 to Leptospira species (MOR, 23.4; 95% CI, 3.6–`). Twenty-six of 51 case-patients had serologic or postmortem evidence of acute leptospirosis. Leptospira …

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Two Capture Techniques For American White Pelicans And Great Blue Herons, D. Tommy King, John D. Paulson, Dwight J. Leblanc, Kevin Bruce May 1998

Two Capture Techniques For American White Pelicans And Great Blue Herons, D. Tommy King, John D. Paulson, Dwight J. Leblanc, Kevin Bruce

United States Department of Agriculture Wildlife Services: Staff Publications

We describe two techniques for capturing American White Pelicans (Pelecanus erythrorhynchos), Great Blue Herons (Ardea herodias), and other large wading birds in aquatic habitats. One technique involved using #3 padded jaw leghold traps modified by replacing both factory coil springs with weaker #1.5 coil springs, to reduce the closing force of the jaws, and replacing the factory chain with a length of aircraft cable and an elastic shock cord, to minimize injury caused by lunging. The second technique involved using a modified portable rocket net that can be set in shallow water. We captured 142 American …

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Effects Of Thinning And Nitrogen Fertilization On Sugars And Terpenes In Douglas-Fir Vascular Tissues: Implications For Black Bear Foraging, Bruce A. Kimball, Eric C. Turnblom, Dale L. Nolte, Doreen L. Griffin, Richard M. Engeman May 1998

Effects Of Thinning And Nitrogen Fertilization On Sugars And Terpenes In Douglas-Fir Vascular Tissues: Implications For Black Bear Foraging, Bruce A. Kimball, Eric C. Turnblom, Dale L. Nolte, Doreen L. Griffin, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

The chemical constituents of coniferous vascular tissues play a role in bear forage selection. In particular, bear foraging preferences are related to the concentrations of simple sugars (nonstructural carbohydrates) and terpenes in the forage. Analyses of vascular tissue samples from trees collected in test plots indicted that both thinning and fertilization caused the sugar concentration of vascular tissues in the lower bole to increase. However, these treatments had no effect on the concentrations of hydrocarbon monoterpenes, oxygenated monoterpenes, or sesquiterpenes. These results may explain the observations that black bears prefer to forage in thinned and fertilized stands.

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Chemically Mediated Foraging Preference Of Black Bears ( Ursus Americanus), Bruce A. Kimball, Dale L. Nolte, Richard M. Engeman, John J. Johnston, Frank R. Stermitz May 1998

Chemically Mediated Foraging Preference Of Black Bears ( Ursus Americanus), Bruce A. Kimball, Dale L. Nolte, Richard M. Engeman, John J. Johnston, Frank R. Stermitz

United States Department of Agriculture Wildlife Services: Staff Publications

The role of chemical constituents in the foraging behavior of black bears (Ursus americanus) was investigated using two field studies. Vascular tissue samples were collected from Douglas-fir (Pseudotsuga menziesii) trees recently foraged by black bears. Samples were extracted and analyzed by liquid and gas chromatography to determine carbohydrates and terpenes, respectively. Chemical data were subjected to correlation analyses and multiple regression to examine if they adequately describe observed foraging preferences. Free-ranging black bears also were offered a choice of four test diets that differed in content of carbohydrates and terpenes. Results indicated that forage preferences were …

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Managing Island Biotas: Brown Treesnake Control Using Barrier Technology, Gad Perry, Earl W. Campbell Iii, Gordon H. Rodda, Thomas H. Fritts Apr 1998

Managing Island Biotas: Brown Treesnake Control Using Barrier Technology, Gad Perry, Earl W. Campbell Iii, Gordon H. Rodda, Thomas H. Fritts

United States Department of Agriculture Wildlife Services: Staff Publications

The brown treesnake (Boiga irregularis), accidentally introduced to the previously snake-free U.S. island of Guam after World War 11, decimated the island's naive wildlife. Today, it periodically stows away on craft going to other islands where the ecological damage may be repeated. Barriers offer an effective tool for keeping the snakes out of areas from which they can disperse off-island, as well as sites identified as critical for the protection of human health, conduct of economic activity, or conservation of endangered species. The authors have developed a variety of barrier designs which repulse at least 95% of snake …

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Trapping Strategies For Deterring The Spread Of Brown Tree Snakes From Guam, Richard M. Engeman, Michael A. Linnell Apr 1998

Trapping Strategies For Deterring The Spread Of Brown Tree Snakes From Guam, Richard M. Engeman, Michael A. Linnell

United States Department of Agriculture Wildlife Services: Staff Publications

The accidental introduction of the Brown Tree Snake Boiga Irregularis to Guam has resulted in the extirpation of most of the island's native terrestrial vertebrates, has presented a health hazard to infants and children, and also has produced an economic problem. Prevention of its dispersal through Guam's cargo traffic to other Pacific islands has became a high environmental priority. Trapping around ports and other cargo staging areas is central to an integrated pest management program designed to deter dispersal of the species. In this study, perimeter trapping of forested plots characteristic of those found in port areas was found 19 …

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A Review Of The Case Histories Of The Brown Tree Snakes (Boiga Irregularis) Located By Detector Dogs On Guam, Richard M. Engeman, Danny V. Rodriguez, Michael A. Linnell, Mikel E. Pitzler Apr 1998

A Review Of The Case Histories Of The Brown Tree Snakes (Boiga Irregularis) Located By Detector Dogs On Guam, Richard M. Engeman, Danny V. Rodriguez, Michael A. Linnell, Mikel E. Pitzler

United States Department of Agriculture Wildlife Services: Staff Publications

Records of 34 brown tree snakes detected during dog inspections were examined to describe the situations in which snakes were found and to determine probable destinations had they successfully departed Guam. A key to the use of detector dogs for interdicting brown tree snake transport from Guam is that the snakes found are at high risk for export. Hawaii. followed by the Micronesian islands. were the most frequently identified potential destinations for the snakes located by dogs. Published by Elsevier Science Ltd.

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Comparative Developmental Toxicity Of Planar Polychlorinated Biphenyl Congeners In Chickens, American Kestrels, And Common Terns, David J. Hoffman, Mark J. Melancon, Patrice N. Klein, John D. Eisemann, James W. Spann Apr 1998

Comparative Developmental Toxicity Of Planar Polychlorinated Biphenyl Congeners In Chickens, American Kestrels, And Common Terns, David J. Hoffman, Mark J. Melancon, Patrice N. Klein, John D. Eisemann, James W. Spann

United States Department of Agriculture Wildlife Services: Staff Publications

The effects of polychlorinated biphenyl (PCB) congeners, PCB 126 (3,3′, 4,4′, 5-pentaCB) and PCB 77 (3,3′4,4′-tetraCB), were examined in chicken (Gallus gallus), American kestrel (Falco sparverius), and common tern (Sterna hirundo) embryos through hatching, following air cell injections on day 4. PCB 126 caused malformations and edema in chickens starting at 0.3 ppb, in kestrels at 2.3 to 23 ppb, but in terns only at levels affecting hatching success (44 ppb). Extent of edema was most severe in chickens and least in terns. Defects of the beak were common in all species but with …

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Cattle Guards Reduce White-Tailed Deer Crossings Through Fence Openings, J. L. Belant, T. W. Seamans, C.P. Dwyer Apr 1998

Cattle Guards Reduce White-Tailed Deer Crossings Through Fence Openings, J. L. Belant, T. W. Seamans, C.P. Dwyer

United States Department of Agriculture Wildlife Services: Staff Publications

In response to increased white-tailed deer (Odocoileus virginianus) encroachment on airports, we evaluated the effectiveness of cattle guards as deer exclusion devices. We conducted three experiments in a 2200 ha fenced facility in northern Ohio with high (91/km2) deer densities during 1994 ± 1995. In each experiment, we monitored deer crossings at two or three cattle guards (4.6[L] x 3[W]x 0.5 or 1.0[D] m) constructed at fence openings for 2 weeks pre- and post-installation. For each experiment, the mean daily number of deer crossings after installation of cattle guards was reduced (P < 0.01) by > 88% compared with …

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