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Articles 36961 - 36990 of 40084
Full-Text Articles in Entire DC Network
Biological Status Of Mountain Lions In California, E. Lee Fitzhugh, W. Paul Gorenzel
Biological Status Of Mountain Lions In California, E. Lee Fitzhugh, W. Paul Gorenzel
Vertebrate Pest Conference Proceedings: 12th (1986)
Mountain lions (Felis concolor) symbolize wilderness. The "wild west," a supreme predator, supreme quarry, destroyer of wildlife (game and nongame), livestock, and "trophy" hunting. They are the epitomy of controversy in California. In this paper we will review the history of management and present legal status of mountain lions in California, the political situation leading to the present status, and some of the biological factors that have been controversial, particularly relating to population status and trends.
Twelfth Vertebrate Pest Conference Frontmatter And Table Of Contents
Twelfth Vertebrate Pest Conference Frontmatter And Table Of Contents
Vertebrate Pest Conference Proceedings: 12th (1986)
Table of Contents
A Changing Approach To Dingo Control In Western Australia, A. W. Hogstrom
A Changing Approach To Dingo Control In Western Australia, A. W. Hogstrom
Vertebrate Pest Conference Proceedings: 12th (1986)
The traditional method of dingo control on sheep properties in Western Australia relied on labor-intensive trapping and baiting. A cost/price squeeze in the rangeland sheep-grazing areas around 1970 forced a revision of these practices. Research was conducted on dingo biology, habitat preference and use, movements, social organization and damage to livestock. The data demonstrated the territorial nature of dingoes, that they usually occur in groups of 2 to 15, that long movements are rare, and that they quickly learn to harass and kill sheep. Aerial baiting trials using factory-manufactured baits and baits prepared from fresh meat demonstrated that an adequate …
Implications And Management Of Feral Mammals In California, Walter E. Howard, Rex E. Marsh
Implications And Management Of Feral Mammals In California, Walter E. Howard, Rex E. Marsh
Vertebrate Pest Conference Proceedings: 12th (1986)
"Feral" is defined. For each of the principal species of feral mammals in California we note the broad ecological implications they have on the environment and the potential or actual management approaches being followed. The main emphasis of this paper, and all of the slides shown, was on how wild horses and burros, two controversial feral species, are managed in California and in other western states. The feral pig is about to become the number one big game animal in California, and mustrats (Ondatra zibethica (L.)), which were introduced or escaped into the Sacramento Valley—-hence locally feral--are the state's …
The Mechanical Control Of Bushpig, Potamochoerus Porcus, In Zimbabwe, Michael La Grange
The Mechanical Control Of Bushpig, Potamochoerus Porcus, In Zimbabwe, Michael La Grange
Vertebrate Pest Conference Proceedings: 12th (1986)
Bushpig, Potamocheorus porcus, occurring naturally in the high rainfall areas of Zimbabwe, have become a major threat to maize producers in the country. Traditional means of control including hunting have been unsuccessful in keeping the numbers to a tolerable level owing to the secretive and cunning nature of the animal. The use of poisons has been discouraged because of indiscriminate use and problems of secondary poisoning, so alternative methods of mechanical control were sought. Several methods evolved during experimentation, producing a strategy to control bushpig throughout the year.
Specifications For Wire Mesh Fences To Exclude The European Wild Rabbit From Crops, I. Gordon Mckillop, Harry W. Pepper, Charles J. Wilson
Specifications For Wire Mesh Fences To Exclude The European Wild Rabbit From Crops, I. Gordon Mckillop, Harry W. Pepper, Charles J. Wilson
Vertebrate Pest Conference Proceedings: 12th (1986)
The sizes of hexagonal and rectangular meshes needed to exclude all age classes of rabbits(Oryctolagus cuniculus) were 31 mm and 50 x 25 mm, respectively. In an enclosure, fences 0.75 m high excluded >90% of adult rabbits, a similar percentage to that obtained using the commonly accepted height of 0.9 m. In a subsequent field experiment using fences with a mesh size of 31 mm and heights of 0.9 m and 0.75 m, the numbers of rabbits seen on protected fields were reduced by about 80% for each height and therefore the 0.75-m-high fence was more cost-effective.
An Approach To The Design Of Target-Specific Vertebrate Pest Control Systems, Peter H. O'Brien
An Approach To The Design Of Target-Specific Vertebrate Pest Control Systems, Peter H. O'Brien
Vertebrate Pest Conference Proceedings: 12th (1986)
Vertebrate pest control has the dual objectives of maximizing efficacy and minimizing nontarget hazard. The task in design is to make these objectives complementary, rather than mutually exclusive. Historically, vertebrate pest control has emphasized target control as a single objective, with nontarget impact a subsequent, secondary consideration. This sequence necessarily constrains the capacity of the design process to minimize nontarget impact. I describe a framework for the design of vertebrate pest control which is based on comparative evaluation of the socioecology of target and potential nontarget species. Using this approach, control systems are designed which focus on and exploit identified …
Bait Preference Field Study Of The California Ground Squirrel, Brenda D. Protopapas, A. Charles Crabb
Bait Preference Field Study Of The California Ground Squirrel, Brenda D. Protopapas, A. Charles Crabb
Vertebrate Pest Conference Proceedings: 12th (1986)
A bait preference field study of the California ground squirrel (Spermophilus beecheyi beecheyi) was performed involving the comparison of the following untreated bait formulations fed ad lib.: oat groats, Ramik Green, and ZP Rodent Ag Bait. The study was performed on rangeland at California Polytechnic State University, San Luis Obispo, California, from March 11, 1984, to September 15, 1984. Poor bait quality problems occurred in the early period of the study (March 11 to May 17), resulting in poor acceptance of both Ramik and Ag Bait. A descriptive analysis of this period is discussed. The statistical analysis of …
Approaches To Small-Holder Rodent Control, C. G. J. Richards
Approaches To Small-Holder Rodent Control, C. G. J. Richards
Vertebrate Pest Conference Proceedings: 12th (1986)
Rodents are now recognized as one of the most important pests damaging crops in countries as far apart as Indonesia, Tanzania and Venezuela (Benigno and Sanchez 1984, Taylor 1984, Williams and Vega 1984). Damage to crops such as rice may be devastating during periodic upsurges in rodent numbers, with yields often reduced by 50% or more. It is being increasingly recognized, however, that continual chronic losses, which commonly occur over very large areas, are economically more significant (Buckle et al. 1985), resulting in yield losses in the range of 5 to 10% of national crops every year in many countries …
Comparison Of Fumigant Gases Used For Rabbit Control In Great Britain, John Ross
Comparison Of Fumigant Gases Used For Rabbit Control In Great Britain, John Ross
Vertebrate Pest Conference Proceedings: 12th (1986)
The two most commonly used fumigant formulations, one generating hydrogen cyanide (HCN) and the other phosphine (PH3), were compared in paired field trials using the spoon-gassing technique. The two formulations were equally effective in reducing rabbit numbers seen in spotlight counts. The PH3 generating formulation was more convenient and slightly cheaper to use. Safety and humaneness aspects of the two formulations are discussed and alternative formulations (generating HCN and PH3) are considered. The potential usefulness (for rabbit control) of some other fumigant gases is briefly reviewed.
Agriculture And Forestry Rodent Problems And Control In Italy, Luciano A. Santini
Agriculture And Forestry Rodent Problems And Control In Italy, Luciano A. Santini
Vertebrate Pest Conference Proceedings: 12th (1986)
Rodent pest problems and their control in Italy are reviewed. Two rats, Rattus norvegicus and Rattus rattus, and the field mouse, Apodemus sylvaticus, are often important pests both in rural and forestry areas. Other species, such as voles, Microtus arvalis and Microtus (Pitymys) savii, in orchards and in horticulture, and Sciurus vulgaris and Myoxus (Glis) glis in forestry, sometimes represent serious problems. For each species the kind of damage and control is recorded, and additional considerations are supplied to the public and private organizations responsible for rodent control.
Rodent Control In East Africa, William R. Smythe
Rodent Control In East Africa, William R. Smythe
Vertebrate Pest Conference Proceedings: 12th (1986)
The nations of East Africa consist of Ethiopia, Somalia, Kenya, Uganda, Tanzania, Malawi, Mozambique and Zimbabwe. They encompass a widely varied topography, from coral strands to snow-capped mountains, rain forests to deserts, and tropical to temperate. In all these areas where soil and rainfall patterns permit, agricultural crops are grown. For the most part farming is of a subsistence nature being small single family plots. These farms make up to 90% of the farming in most of the East African nations. There are large farms in Kenya and Zimbabwe generally confined to the temperate uplands. Elsewhere there are large government …
Approaches To Coot Management In California, Valerie Van Way
Approaches To Coot Management In California, Valerie Van Way
Vertebrate Pest Conference Proceedings: 12th (1986)
Coot depredations have been documented in California since 1886, and shooting has been relied on as the principal means of mitigating damage. Immobilizing agents continue to offer promise as useful nonlethal tools for population reduction programs. Exploration of the use of tribromoethanol in coot capture is described, and the potential for other bird management techniques is discussed.
An Evaluation Of The Acute Oral Toxicity Of Brodifacoum To Birds, Michael E. R. Godfrey
An Evaluation Of The Acute Oral Toxicity Of Brodifacoum To Birds, Michael E. R. Godfrey
Vertebrate Pest Conference Proceedings: 12th (1986)
Single acute doses of the rodenticide brodifacoum were administered orally to 13 species of birds which are at risk from accidental poisoning during rabbit or possum control operations. Median lethal dose values from less than 1 to more than 20 mg/kg were obtained for some species. Gulls and Canada geese appear to be particularly susceptible. Several species, particularly the gulls, waxeyes, sparrows, mallard ducks and harrier hawks, seem to be vulnerable to lead poisoning.
A Five-Year Evaluation Of The Silvicultural Treatments For The Control Of Squirrel Damage In Taiwan, Pao-Chang Kuo, Yue-Ken Liao
A Five-Year Evaluation Of The Silvicultural Treatments For The Control Of Squirrel Damage In Taiwan, Pao-Chang Kuo, Yue-Ken Liao
Vertebrate Pest Conference Proceedings: 12th (1986)
The Formosan red-bellied tree squirrel (Callosciurus erythraeus. ) is a pest animal that causes serious damage to many conifer plantations in Taiwan. Poisoning has been the major means to control the damage. The feasibility of forestry control through habitat manipulation has been evaluated during the past 5 years. The objective of this study was to investigate the effects of forest-tending operations on the activity and damage by squirrels. Forest-tending conducted included weeding and thinning. Test sites were at three Japanese cedar (Cryptomeria japonica) plantations located in Chitou. The results of this study revealed that squirrel activity in …
Results Of Eight Years' Examination Of The Habitats Of Residual Urban Norway Rat Populations After Eradication, Daniel Bajomi, Katalin Sasvari
Results Of Eight Years' Examination Of The Habitats Of Residual Urban Norway Rat Populations After Eradication, Daniel Bajomi, Katalin Sasvari
Vertebrate Pest Conference Proceedings: 12th (1986)
In Budapest (population 2 million) 33 out of 100 buildings were rat-infested in the early seventies. Thus general deratization was decreed to cover the whole of the city in 1971 to 1972. As a result of the global eradication method applied, the rate of rat-infested premises could be reduced below 0.5% annually. After control the sparsely occurring rats could freely choose any of the habitats released for settling. The habitats of Budapest most preferred by Norway rats are presented after a wide-ranging investigation carried out over 8 years. Our examination data support and in some cases reveal the requirements of …
Development And Validation Of A Dynamic Model Of Growth And Quality For Cool Season Grasses, W. F. Brown, Lowell E. Moser, Terry J. Klopfenstein
Development And Validation Of A Dynamic Model Of Growth And Quality For Cool Season Grasses, W. F. Brown, Lowell E. Moser, Terry J. Klopfenstein
Department of Agronomy and Horticulture: Faculty Publications
A daily time step model simulating growth and quality of cool season grasses was developed and validated for smooth brome (Bromus inermis Leyss.) under varying environmental and management conditions. Growth predictions are based upon genetic potential, environmental temperature, leaf area, soil moisture, and nitrogen fertilization rate. Daily potential growth rate is a composite of two functions—one relating grass species maximum growth rate to minimum, optimum, and maximum temperatures for plant growth, and another relating daily minimum and maximum air temperatures to time. Multipliers are developed for available leaf area, moisture, and nitrogen, and the minimum of these values modifies …
Tillage Systems For Row Crop Production, Elbert C. Dickey, Paul J. Jasa, Alice J. Jones, David P. Shelton
Tillage Systems For Row Crop Production, Elbert C. Dickey, Paul J. Jasa, Alice J. Jones, David P. Shelton
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Selecting the tillage system best suited to a particular farming situation is an important management decision. Formerly, the traditional system was a moldboard plow operation followed by several secondary tillage operations before planting. This system can be appropriate for poorly drained soils having little or no slope and low erosion potential. However, plowing has several disadvantages . The potential for soil erosion is high on sloping lands, and labor and fuel requirements can be substantially higher than with other tillage and planting systems.
Today, conservation tillage systems are used to reduce preplant tillage operations, thus reducing soil erosion and moisture …
The Prairie Naturalist Volume 18, No. 1. March 1986
The Prairie Naturalist Volume 18, No. 1. March 1986
The Prairie Naturalist
Paul B. Kannowski, Editor
Nikki R. Seabloom, Assistant Editor
Douglas H. Johnson, Book Review Editor
TABLE OF CONTENTS
INVASION PATTERN MAPPING OF NON-SEEDED SPECIES ON A SHALLOWLY DISTURBED SEEDED SITE ▪ C. E. Grygiel, C. D. Bonham, and E. F. Redente
CHANGES IN THE LICHEN FLORA OF PIPESTONE NATIONAL MONUMENT, MINNESOTA ▪ G. D. Willson and T. W. Vinyard
INTERPOPULATION VARIABILITY IN MOUTHPARTS IN Scaphiopus bombifrons IN NEBRASKA (AMPHIBIA: PELOBATIDAE) ▪ T. L. Potthoff and J. D. Lynch
PLANTS AND INVERTEBRATES IN A PRAIRIE WETLAND DURING DUCK BROOD-REARING J. W. McCrady, W. A. Wentz, and R. L. Linder
OCCURRENCE OF …
The Prairie Naturalist Volume 18, No. 3 September 1986
The Prairie Naturalist Volume 18, No. 3 September 1986
The Prairie Naturalist
Paul B. Kannowski, Editor
Nikki R. Seabloom, Assistant Editor
Douglas H. Johnson, Book Review Editor
TABLE OF CONTENTS
HABITAT SELECTION AND MOVEMENT PATTERNS IN SANDHILLS RODENTS ▪ C. A. Lemen and P. W. Freeman
THE HERPETOFAUNA OF THE WEAVER DUNES, WABASHA COUNTY, MINNESOTA ▪ P. A. Cochran
MULTIPLE EGG CLUTCH PRODUCTION IN THE GREAT PLAINS TOAD ▪ J. J. Krupa
MAMMALS OF THE KONZA PRAIRIE RESEARCH NATURAL AREA, KANSAS ▪ E. J. Finck, D. W. Kaufman, G. A. Kaufman, S. K. Gurtz, B. K. Clark, L. J. McLellan, and B. S. Clark
AQUATIC INVERTEBRATES IN LEVEL DITCHES AND ADJACENT EMERGENT …
The Probe, Issue 60 - February 1986
The Probe, Issue 60 - February 1986
The Probe: Newsletter of the National Animal Damage Control Association
THE PROBE
National Animal Damage Control Association
FEBRUARY, 1986
National Wool Grower’s Convention
Animal Rights
Toxic Collar
Trapping Figures
Red Fox and Ducks
Letters to Ye Ed
The Coyote
Master Trapper of the Year
What do Coyotes Eat?
Do-it-Yourself Skunk Control
Killer Beavers
Audubon Society
7. The Future Of Clinical Assessment, Jay Ziskin
7. The Future Of Clinical Assessment, Jay Ziskin
The Future of Testing
At the outset, this writer's frame of reference should be made clear. It is the perspective of the author of a book that contains more than five hundred references from the scientific and professional literature which raise doubts about the expertise of clinicians in their role as diagnosticians in general, and also, specifically, within the forensic arena. The perspective further is that of one who provides a consultation service to lawyers pointing out to them the weakness and shortcomings of psychiatric and psychological reports and testimony both in terms of the inherent problems and of any specific deficiencies of omission …
2. Testing Old, Testing New: Schoolboy Psychology And The Allocation Of Intellectual Resources, Gene V. Glass
2. Testing Old, Testing New: Schoolboy Psychology And The Allocation Of Intellectual Resources, Gene V. Glass
The Future of Testing
There will be no divining of the future here- no megatrends, no reference to Orwell (except this one). What little we truly know about the future does not bear mentioning. Nor shall I refer to micro-computers, data banks, and other gaudy paraphernalia that the future holds for us. The future is best seen in a rear-view mirror. We can at least hope to see more clearly the recent past we have traversed. Appearances of rapid change are usually superficial. If we see the past and present clearly, we will know as much of our future as it is ever permitted …
3. Computer Technology In Testing, Gale H. Roid
3. Computer Technology In Testing, Gale H. Roid
The Future of Testing
COMPUTER TECHNOLOGY IN TESTING
Although computers have had an important role in educational and psychological testing for decades, the widespread availability of personal computers has focused interest on the appropriate role of computerization in the development, administration, scoring, and interpretation of tests. Although the early decades of computer usage found hardware and services concentrated in large computer installations, future decades will find hardware and services distributed more widely among individual users. With this rapid diffusion of technology and the lightning speed with which technology is changing, it will be increasingly difficult to predict the directions that computerized testing will take. …
8. Perspectives On The Future Of Neuropsychological Assessment, Raymond S. Dean
8. Perspectives On The Future Of Neuropsychological Assessment, Raymond S. Dean
The Future of Testing
PERSPECTIVES ON THE FUTURE OF NEUROPSYCHOLOGICAL ASSESSMENT
The relationship between human behavior and the functioning of the brain has intrigued scholars for centuries. Although the antecedents are clear, our present knowledge of the relationship between observable behavior and the physiology of the central nervous system owes more to the research vigor of the past 40 years than any other time in history . Of continuing interest to psychologists and other neuroscientists has been evidence of the correspondence between the functioning of the brain and cognitive, sensorimotor and affective dimensions of behavior. With such knowledge as a foundation has come the …
The Future Of Testing: Complete Work, James V. Mitchell Jr., Barbara S. Plake, Joseph C. Witt
The Future Of Testing: Complete Work, James V. Mitchell Jr., Barbara S. Plake, Joseph C. Witt
The Future of Testing
The Future of Testing: Complete Work (320 pages)
Digital Edition Copyright 2012 Buros Center for Testing
This book may not be downloaded, saved, and printed by an individual for their own use. No part of this book may be re-published, re-posted, or redistributed without written permission of the holder of copyright.
Copyright © 1986 by Lawrence Erlbaum Associates, Inc. All rights reserved. No part of this book may be reproduced in any form, by photostat, microform , retrieval system, or any other means , without the prior written permission of the publisher.
Lawrence Erlbaum Associates, Inc. , Publishers 365 Broadway …
Breeding Objectives And Selection Traits For Extensive Beef Cattle Production In The Tropics, D. J. S. Hetzel, G. W. Seifert
Breeding Objectives And Selection Traits For Extensive Beef Cattle Production In The Tropics, D. J. S. Hetzel, G. W. Seifert
World Congress on Genetics Applied to Livestock Production: 3rd (1986)
Breeding objectives are largely determined by market requirements. In the tropics the overall breeding objective can be considered in terms of growth, reproductive rate, carcass quality, adaption and temperament. Growth rate is a simple efficient selection trait. Reasons why potential increases in mature size are not as disadvantageous as in temperate areas are discussed. Reproductive performance has been less important in harsh than benign environments because of the later age of turnoff and higher drought risk of fertile cows. Current market trends towards younger slaughter stock highlight the need to identify marker traits in bulls for cow fertility. Adaptive traits …
Comparison Of Five Dam Breeds Under Two Nutritional Environments, C. E. Thompson, S. G. Woods, S. E. Meadows
Comparison Of Five Dam Breeds Under Two Nutritional Environments, C. E. Thompson, S. G. Woods, S. E. Meadows
World Congress on Genetics Applied to Livestock Production: 3rd (1986)
Crossbreeding has become an accepted practice for beef cattle production. Hybrid vigor or heterosis of crosses among breed of English origin, such as Angus, Hereford and Shorthorn have been well documented. Crosses utilizing breeds of European and dairy breeding have not been well documented for beef production, particularly in the Southeastern part of the United States. As most of the Southeastern U.S. is heavily involved in one-calf programs an evaluation of crossbreds involving the use of British, European and dairy breeding is needed. This study is a portion of a comprehensive research project evaluating the performance of 5 dam breed …
Economic Evaluation Of Breeding Objectives For Milk And Beef Production In Tropical Environments, F. E. Madalena
Economic Evaluation Of Breeding Objectives For Milk And Beef Production In Tropical Environments, F. E. Madalena
World Congress on Genetics Applied to Livestock Production: 3rd (1986)
The influence of some elements of tropical milk production systems on breeding objectives is discussed. Expansion of demand for milk and meat should be expected from increased population and income growth. Relative commercial value of milk fat may be strongly influenced by government policies regulating to proportion of liquid milk consumed. Calf production is an integral part of cow performance under the common practices of hand milking and suckling. Milk letdown may be an important trait for milking in modern dairy parlours. Experimental economic evaluations have referred mainly to comparisons of breeds and crosses, indicating that European × zebu crosses …
Evaluation And Utilization Of Tropical Breeds For Efficient Beef Production In The Tropics: Challenges And Opportunities, Assefaw Tewolde
Evaluation And Utilization Of Tropical Breeds For Efficient Beef Production In The Tropics: Challenges And Opportunities, Assefaw Tewolde
World Congress on Genetics Applied to Livestock Production: 3rd (1986)
Crossbreeding results between tropical breeds and European beef breeds as well as within breed (mainly Zebu) genetic variability for some economically important traits is reviewed. Heterosis of between 9% to 11% has been reported for preweaning growth rate, 2% to 11% for postweaning and carcass traits as well as up to 15% for reproduction related traits in crosses involving Bos indicus and Bos taurus cattle. Maximum heterosis was observed in crosses involving Zebu and Criollo cattle, both well adapted to the tropics. Within breed genetic parameter estimates under tropical conditions are still scanty. Based on the production environment and after …