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Articles 5221 - 5250 of 6879

Full-Text Articles in Physical Sciences and Mathematics

Black Bear Feeding On Second Growth Redwoods: A Critical Assessment, Gregory A. Giusti Mar 1990

Black Bear Feeding On Second Growth Redwoods: A Critical Assessment, Gregory A. Giusti

Vertebrate Pest Conference Proceedings: 14th (1990)

Black bear (Ursus americanus) feeding on coastal redwood (Sequoia sempervirens) has been documented for several years. Quantitative analysis of the feeding damage has not been done. Feeding damage was analyzed on six belt transects in two drainages of the Smith River, Del Norte County, California. Bears are selecting trees of specific d.b.h. classes and not feeding on the size class most abundant. Damage estimates are presented for number of trees per hectare and percentage of stands that are impacted by bear feeding. A proposed approach to bear management is presented with emphasis on a multi-management approach.

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The Status Of The Steel Trap In North America, James H. Glass Mar 1990

The Status Of The Steel Trap In North America, James H. Glass

Vertebrate Pest Conference Proceedings: 14th (1990)

This paper will discuss strides taken to limit or eliminate use of the leghold trap and will explore recent trends in the animal rights movement's attack on fur and traps. A current legislative effort in Ohio, which seeks to protect wearers of fur and other animal products, as well as retailers, will be examined. Finally, the outlook as to what the future holds for the anti-trap debate and what we must do as responsible conservationists is discussed.

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Seedling Damage And Mortality Of Conifer Plantations On Transitory Ranges In Northern And Central Idaho, Russell T. Graham, James L. Kingery Mar 1990

Seedling Damage And Mortality Of Conifer Plantations On Transitory Ranges In Northern And Central Idaho, Russell T. Graham, James L. Kingery

Vertebrate Pest Conference Proceedings: 14th (1990)

A combination of factors are responsible for mortality in conifer plantations. Ponderosa pine (Pinus ponderosa) were planted on 3 transitory ranges in northern and central Idaho. These plantations were followed closely (sampling up to 7 times per year) for 6 years recording the causes of mortality and damage to the tree seedlings. Pocket gophers (Thomomys spp.) killed the most trees (71%) while nonanimal causes killed 21%. Elk (Cervus elaphus) and deer (Odocoileus spp.) killed a maximum of 9%, and cattle (Bovine spp.) killed a maximum of 4%. Pocket gophers caused the most reduction …

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Adc Guarding Dog Program Update: A Focus On Managing Dogs, Jeffrey S. Green, Roger A. Woodruff Mar 1990

Adc Guarding Dog Program Update: A Focus On Managing Dogs, Jeffrey S. Green, Roger A. Woodruff

Vertebrate Pest Conference Proceedings: 14th (1990)

One hundred dogs were placed with sheep producers in Idaho, Oregon, Washington, and Wyoming during summer 1987 through summer 1988 as part of the APHIS-ADC livestock guarding dog program. Mortality as of February 1990 from culling and accidents is 39% and was evenly split between the first and second year of life. The 60 dogs currently working were rated as follows: 78% good, 12% fair, and 10% poor. All dogs rated good or fair were judged to have reduced predation or helped to keep predation minimized. Success of the dogs was breed-related but did not differ between pasture and rangeland …

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Control Of Mediterranean Pine Vole Populations In The South Of France, Gerald Guedon, Benoit Combes Mar 1990

Control Of Mediterranean Pine Vole Populations In The South Of France, Gerald Guedon, Benoit Combes

Vertebrate Pest Conference Proceedings: 14th (1990)

The control of the Mediterranean pine vole through manual bait placement is too fastidious. It prevents the realization of collective control on large areas. In this situation, mechanization is necessary. A burrow builder, made of a tubular ploughshare, has been devised in order to make artificial runs in the soil where baits may be deposited. This plough was successfully tested in fall 1989 in apple orchards with a wheat-based bait treated with chlorophacinone, chosen for its good resistance to moisture. The treatment efficiency varied between 86.7% and 96.4% with 25 and 50 artificial runs per hectare, respectively. A humid but …

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Vertebrate Pests Of Uk Agriculture: Present Problems And Future Solutions, Anthony R. Hardy Mar 1990

Vertebrate Pests Of Uk Agriculture: Present Problems And Future Solutions, Anthony R. Hardy

Vertebrate Pest Conference Proceedings: 14th (1990)

The status of damage by vertebrate pests to growing and stored agricultural crops is reviewed in the light of changing patterns of agricultural practice and land use within the UK. Significant problems and existing management techniques are briefly discussed. The results of recent research by the Agricultural Department and Advisory Service (ADAS) of the Ministry of Agriculture, Fisheries and Food are explored to indicate the future direction of vertebrate pest management to reduce crop damage. Recent changes in legislation and public attitudes impose constraints on some of the approaches to solving problems. The continued role of traditional control methods is …

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Field Trial Of A Cpt-Avicide Aerial Spray, Jon F. Heisterberg, John L. Cummings, George M. Linz, Edward Knittle, Thomas W. Seamans, Paul P. Woronecki Mar 1990

Field Trial Of A Cpt-Avicide Aerial Spray, Jon F. Heisterberg, John L. Cummings, George M. Linz, Edward Knittle, Thomas W. Seamans, Paul P. Woronecki

Vertebrate Pest Conference Proceedings: 14th (1990)

A 2.2 ha-cedar and mixed deciduous tree woodlot in Crawford, Mississippi, harboring 330,000 blackbirds (Icterinae) and European starlings (Sturnus vulgaris) was aerially sprayed by helicopter the night of 1 March 1989 with 1050 1 of a CPT-avicide formulation at a rate of 49 kg CPT/ha. Most mortality occurred within 36 h of treatment. Mortality in the roost was 3% of the pretreatment population. No reliable technique to estimate out-of-roost mortality was identified. Pilot misapplication and probable CPT volatilization of the spray formulation contributed to the low mortality. Only 1 of 37 radiotagged blackbirds using the roost the night …

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How Animal Control Improves Animal Welfare, Walter E. Howard Mar 1990

How Animal Control Improves Animal Welfare, Walter E. Howard

Vertebrate Pest Conference Proceedings: 14th (1990)

The balance of nature requires a balanced predator-prey relationship. In agriculture or urban areas the natural predator-prey balance is disrupted because the habitats have been altered and, for the protection of livestock (and for humans in case of grizzly bears, lions, and wolves), the large carnivores have usually been displaced. Consequently, in these altered environments to prevent crop depredations, to keep other vertebrate species in balance with their environment, and to protect some endangered species, people must manage the wildlife. This often means that for the welfare of animals people have to become predators to assist nature. Fortunately, from an …

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Differential Toxicity And Taste Aversion To Strychnine Of Three Subspecies Of The California Ground Squirrel (Spermophilus Beecheyi), Walter E. Howard, Stephen D. Palmateer, Rex E. Marsh Mar 1990

Differential Toxicity And Taste Aversion To Strychnine Of Three Subspecies Of The California Ground Squirrel (Spermophilus Beecheyi), Walter E. Howard, Stephen D. Palmateer, Rex E. Marsh

Vertebrate Pest Conference Proceedings: 14th (1990)

Three subspecies of the California ground squirrel (Spermophilus beecheyi) were studied. In the first test of Experiment 1, Beechey (S. b. beecheyi), Douglas (S. b. douglasii), and, for comparative purposes, Sierra (S. b. sierrae) ground squirrels were each offered a drinking tube containing one of three H20 solutions of strychnine sulfate (0.01, 0.05, or 0.5%) after being deprived of water for 23 hr. In Test 2 the survivors of Test 1 were offered for 24 hr a free choice of distilled water and two of the above concentrations of strychnine …

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The Evolution Of Vertebrate Pest Management--The Species Versus Systems Approach, Scott E. Hygnstrom Mar 1990

The Evolution Of Vertebrate Pest Management--The Species Versus Systems Approach, Scott E. Hygnstrom

Vertebrate Pest Conference Proceedings: 14th (1990)

Wildlife management has evolved through a series of stages, with early efforts directed toward individual species. Since the late 1800s, however, more wildlife applications have incorporated a systems approach, where communities are managed to promote the quality, quantity, and fitness of most associated species. Vertebrate pest management has followed a similar course of development, although it has lagged behind in addressing the concept of systems management. I propose that a systems approach to vertebrate pest management should include the consideration of all potential problem species of an area or situation and should integrate damage prevention and control strategies that minimize …

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Controlling Vertebrate Animal Damage In Southern Pines, Jeffrey J. Jackson Mar 1990

Controlling Vertebrate Animal Damage In Southern Pines, Jeffrey J. Jackson

Vertebrate Pest Conference Proceedings: 14th (1990)

Certain mammals and birds may damage or destroy southern pines, causing economic losses in intensively cultured areas such as seed orchards and nurseries. Mammal pests may eat seeds; tunnel, dislodging seedlings, or chew on roots; or girdle, debark, or sever stems or branches. Bird pests may eat seeds or excavate holes in the tree trunks. The first important step is to identify the pest(s) from the damage left behind. Thereafter, various control options-from using traps and repellents to altering habitat-are available.

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Required Use Of Protective Bait Stations In The U. S., William W. Jacobs Mar 1990

Required Use Of Protective Bait Stations In The U. S., William W. Jacobs

Vertebrate Pest Conference Proceedings: 14th (1990)

Beginning in the 1960s, labels for federally registered commensal rodenticides have been required to bear a statement to the effect that the baits are to be contained in "tamper-proof bait boxes" when used in locations accessible to children and nontarget animals. Faced with ample evidence of noncompliance with the letter and spirit of this portion of the label, the U. S. Environmental Protection Agency (EPA) issued a policy statement (PR Notice 83-5) and scheduled public hearings on matters pertaining to bait stations and nontarget exposure incidents involving rodenticides. EPA's findings indicate that, while some clarifications of its policies might be …

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The Human Element In Wildlife Damage Situations, Ron J. Johnson Mar 1990

The Human Element In Wildlife Damage Situations, Ron J. Johnson

Vertebrate Pest Conference Proceedings: 14th (1990)

The field of prevention and control of wildlife damage is changing and evolving along with clientele needs, pressures from user and non-user groups, and other factors. A theoretical overview of the field may offer an action model regarding changing trends and potential responses. I propose that three things happen every time a wildlife damage problem occurs: 1) A human activity, desire, or need is interfered with, 2) the experience fosters an opinion about a wild animal - usually negative, and 3) a decision is made to tolerate the situation or to control it. If control is selected, availability and effectiveness …

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State Of The Art Telemetry Equipment Appropriate For Vertebrate Pest Control Research, Barbara C. Kermeen Mar 1990

State Of The Art Telemetry Equipment Appropriate For Vertebrate Pest Control Research, Barbara C. Kermeen

Vertebrate Pest Conference Proceedings: 14th (1990)

Constant developments in technology, both materials and methods, allow smaller and smaller animals to be radio-tracked for longer periods of time than was previously possible. Developments in electronic component miniaturization and battery chemistry are primarily responsible for this advancement. Approximately 30 years of field-use of radiotelemetry techniques have led to innovative procedures and uses of materials for the application of transmitters to animals. New technology such as satellite telemetry and recapture collars are only in their infancy and are not, at this time, appropriate for use in vertebrate pest research. Sophistication in receiving systems also allows more accurate and more …

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Control Of The African Striped Ground Squirrel, Xerus Erythropus, In Kenya, Gillian E. Key Mar 1990

Control Of The African Striped Ground Squirrel, Xerus Erythropus, In Kenya, Gillian E. Key

Vertebrate Pest Conference Proceedings: 14th (1990)

The African striped ground squirrel, Xerus erythropus (E. Geoffroy), has been found to constitute a serious pest to maize seed at the planting stage, causing mean losses of 9.7% and accounting for 57.3% of total damage found. A feature of ground squirrel damage is its unpredictable nature. Methods of reducing losses of planted maize seed to X. erythropus at the subsistence farmer level in southern Kenya were investigated. Constraints affecting a control program by farmers were identified as follows: low standards of living and education, limited financial resources, strong individualistic attitude of farmers and small field size in relation to …

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Status Of Compound Drc-1339 Registrations, C. Edward Knittle, Edward W. Schaffer Jr., Kathleen A. Fagerstone Mar 1990

Status Of Compound Drc-1339 Registrations, C. Edward Knittle, Edward W. Schaffer Jr., Kathleen A. Fagerstone

Vertebrate Pest Conference Proceedings: 14th (1990)

Compound DRC-1339 is a restricted-use, slow-acting avicide that is registered to control a number of avian pests. It is unique because of its selective high toxicity to most pest birds, low-to-moderate toxicity to most mammals and predatory birds, and lack of known secondary hazards when used on baits. The most widely known product containing DRC- 1339 is Purina Mills’ Starlicide Complete®, a pelleted bait used to control blackbirds and starlings in feedlots. Other DRC- 1339 registrations are held by the U.S. Department of Agriculture, Animal and Plant Health Inspection Service (USDA/APHIS), for the use of nonpelletized baits at feedlots and …

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Frightening Methods And Devices/Stimuli To Prevent Mammal Damage-- A Review, Ann E. Koehler, Rex E. Marsh, Terrell P. Salmon Mar 1990

Frightening Methods And Devices/Stimuli To Prevent Mammal Damage-- A Review, Ann E. Koehler, Rex E. Marsh, Terrell P. Salmon

Vertebrate Pest Conference Proceedings: 14th (1990)

Various frightening stimuli, primarily visual and acoustic, have been used to prevent or alleviate damage by depredating mammals (e.g., deer (Odocoileus spp.), raccoons (Procyon lotor), tree squirrels (Sciurus spp.), coyotes (Canis latrans). Frightening methods are most appropriate for use where a crop or situation needs protection from pest mammals for only a period of a few days or weeks. The ability of animals to habituate to such stimuli limits their long-term usefulness. Against nocturnal species, various types of lights and noisemakers are the most useful. Combining acoustic and visual stimuli can enhance effectiveness, while …

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Lyme Disease, With Emphasis On The Western U.S., And Its Relationship To Wildlife (Abstract Only), Robert S. Lane Mar 1990

Lyme Disease, With Emphasis On The Western U.S., And Its Relationship To Wildlife (Abstract Only), Robert S. Lane

Vertebrate Pest Conference Proceedings: 14th (1990)

In the western United States, Lyme disease has been reported primarily from the three Pacific states, especially California, and sporadically or not at all from various mountain states. In California, surveillance for Lyme disease was initiated in 1983, but it was not made a reportable disease in this state until 1989. Nevertheless, approximately 400 human cases were reported by California State Health authorities between 1983 and 1987. In 1982, I began studying the ecology and epidemiology of Lyme disease in the far-western United States in collaboration with Dr. Willy Burgdorfer of the Rocky Mountain Laboratories, Hamilton, Montana, and others. The …

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Acquired Strychnine Tolerance By Pocket Gophers, Ling Ling Lee, Walter E. Howard, Rex E. Marsh Mar 1990

Acquired Strychnine Tolerance By Pocket Gophers, Ling Ling Lee, Walter E. Howard, Rex E. Marsh

Vertebrate Pest Conference Proceedings: 14th (1990)

Four adult female Botta's pocket gophers (Thomomys bottae) that had survived many normally potentially lethal doses of strychnine alkaloid in another experiment (Lee 1986) were examined further. These individuals freely consumed 0.5% strychnine bait, and 3 of them also 1% strychnine bait, for long periods without dying, whether or not nontoxic alternate bait was present. After 1 gopher (#5) was taken off its 1% strychnine wheat diet for 44 days, it lost its physiological tolerance to strychnine and died the first day when again exposed to a free choice of nontoxic and 1% strychnine wheat. It consumed only …

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The Use Of Rainfall Patterns In Predicting Population Densities Of Multimammate Rats, Mastomys Natalensis, H. Leirs, R. Verhagen, W. Verheyen Mar 1990

The Use Of Rainfall Patterns In Predicting Population Densities Of Multimammate Rats, Mastomys Natalensis, H. Leirs, R. Verhagen, W. Verheyen

Vertebrate Pest Conference Proceedings: 14th (1990)

During 3 years we studied a population of multimammate rats, Mastomys natalensis (Smith 1834), in Morogoro, Tanzania. Data were collected in both removal and capture-recapture schemes. We present evidence that patterns of growth and reproduction were related to onset and abundance of rains. This partially explains differences in densities. Additionally, we investigated available literature data and related them with climatological data. A scenario is presented which enables us to predict how densities of multimammate rats may evolve in the following year and whether there will be a risk of outbreaks. The use and implications of this scenario in planning control …

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Survey Of Rodent And Rabbit Damage To Alfalfa Hay In Nevada, Steven R. Lewis, John M. O'Brien Mar 1990

Survey Of Rodent And Rabbit Damage To Alfalfa Hay In Nevada, Steven R. Lewis, John M. O'Brien

Vertebrate Pest Conference Proceedings: 14th (1990)

A survey of alfalfa hay producers was conducted to characterize vertebrate pest problems in Nevada alfalfa hay and help attract research funding. Damage to alfalfa hay by pocket gophers (Thomomvs spp), ground squirrels (Spermophilus spp), black-tailed jackrabbits (Lepus californicus) and meadow voles (Microtus montanus) was assessed. Presence of vertebrate pests along with a ranking of cost-related problems they pose to alfalfa hay operations was determined. Pocket gophers were the most costly pest followed by ground squirrels, jackrabbits, and meadow voles. The number one problem caused by vertebrate pests was identified to be a decrease …

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Effects Of Field Vertebrate Pest Control On Nontarget Wildlife (With Emphasis On Bird And Rodent Control), E.E. Littrell Mar 1990

Effects Of Field Vertebrate Pest Control On Nontarget Wildlife (With Emphasis On Bird And Rodent Control), E.E. Littrell

Vertebrate Pest Conference Proceedings: 14th (1990)

Vertebrate pest control measures may have an impact on nontarget wildlife. Bird and rodent control programs using avicides and rodenticides in California have been, and are currently being, examined by the California Department of Fish and Game on a routine basis. Each pesticide used has its deleterious side effects. This paper reviews these side effects and suggests possible future impacts which could be expected.

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Reproduction And Population Structure Of Pocket Gophers (Thomomvs Bottae) From Irrigated Alfalfa Fields, Susan C. Loeb Mar 1990

Reproduction And Population Structure Of Pocket Gophers (Thomomvs Bottae) From Irrigated Alfalfa Fields, Susan C. Loeb

Vertebrate Pest Conference Proceedings: 14th (1990)

Pocket gophers were collected from irrigated alfalfa fields (IRR) and non-irrigated fallow fields (NIRR) in Davis, California, for 2 years. Reproduction was continuous in IRR fields with very little seasonal variation in reproductive activity. In contrast, reproduction in NIRR fields occurred primarily during the rainy season (winter and spring). Females in IRR fields produced approximately twice as many litters per year (3.6-3.9) as females in NIRR habitats (1.7). The high reproductive potential of adult females in IRR fields coupled with the early age of sexual maturity among young females suggests that population recovery after control measures is likely to be …

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Urban Animal Damage Control In California, John R. Maestrelli Mar 1990

Urban Animal Damage Control In California, John R. Maestrelli

Vertebrate Pest Conference Proceedings: 14th (1990)

Requests for assistance, monetary losses attributed to wildlife, and numbers of wild animals removed from urban areas in California increased significantly between 1982 and 1989. Five species of wildlife are responsible for the majority of complaints received from the public. Because of the inherent problems associated with animal damage control in densely populated urban areas, specialized control equipment and techniques such as cage traps, crossbows and night vision goggles are utilized by U.S. Department of Agriculture, Animal Plant Health Inspection Service, Animal Damage Control (USDA-APHISADC) personnel. Urban ADC programs help educate a large segment of the population about the need …

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Microencapsulation Of Rodenticides, Rex E. Marsh Mar 1990

Microencapsulation Of Rodenticides, Rex E. Marsh

Vertebrate Pest Conference Proceedings: 14th (1990)


Microencapsulation materials and techniques have advanced significantly over the past two decades. Encapsulation techniques are now used in a wide range of products from drugs to perfumes and food fragrances. As an industry, microencapsulation had its beginning in the research laboratories of National Cash Register (NCR) in Dayton, Ohio, in the late 1930s. It came into commercial use in 1954 when carbonless copy paper was introduced on the market. The entire field has made enormous progress since that time.

Microencapsulation and other associated controlled- release technology play an important role in time-release pesticides, giving them a delayed or longer action …

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Exclusionary Methods And Materials To Protect Plants From Pest Mammals--A Review, Rex E. Marsh, Ann E. Koehler, Terrell P. Salmon Mar 1990

Exclusionary Methods And Materials To Protect Plants From Pest Mammals--A Review, Rex E. Marsh, Ann E. Koehler, Terrell P. Salmon

Vertebrate Pest Conference Proceedings: 14th (1990)


Protecting individual plants or small clumps of plants with some type of protective material or device represents a positive nonlethal approach to damage prevention that is often much less expensive than fencing an entire garden or crop or netting over the entire area to prevent damage by such species as deer (Odocoileus spp.), rabbits (Lepus spp., Sylvilagus spp.), and ground squirrels (Spermophilus spp.). This review article does not include fencing or the netting or screening of entire crops, which are subjects unto themselves.

Tree trunk guards or protectors include commercial tree wraps and other materials affixed directly …

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Bird Control On Containment Pond Sites, Lee R. Martin, Sam Hagar Mar 1990

Bird Control On Containment Pond Sites, Lee R. Martin, Sam Hagar

Vertebrate Pest Conference Proceedings: 14th (1990)

Bird deaths resulting from toxic materials in containment ponds are causing authorities to insist that action be taken to eliminate this hazard to avian wildlife. Bird control at containment pond sites is achieved by two well-known but poorly understood aversion techniques: hazing systems (sound/visual) and stretch wire. The limiting condition of either approach is that resident birds rapidly habituate while some migrating species are totally unaffected. Consequently, one must be able to accept degrees of control with an understanding of the behavior of the species involved. Birdproofing is achieved by covering an entire pond with bird net. This presentation discusses …

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An Examination Of The Browsing Animal Problem In Australian Eucalypt And Pine Plantations, Thomas L. Montague, David C. Pollock, Wendy Wright Mar 1990

An Examination Of The Browsing Animal Problem In Australian Eucalypt And Pine Plantations, Thomas L. Montague, David C. Pollock, Wendy Wright

Vertebrate Pest Conference Proceedings: 14th (1990)

The severity and extent of browsing damage to pine and eucalypt plantations and possible solutions are examined. Twenty-six percent of all trees surviving 9 months after planting were browsed yet only six percent had more than 50% of foliage damaged. The most common form of damage was for the foliage to be browsed or the tree bitten off with browsing damage implicated in the mortality of the 24% of trees that died. No difference in the extent of damage between Pinus radiata and eucalypts was detected. Slight differences between three Eucalypt species and two ages of seedlings were detected; however, …

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Assessment Of Bird Damage To Early-Ripening Blueberries In Florida, Curtis O. Nelms, Michael L. Avery, David G. Decker Mar 1990

Assessment Of Bird Damage To Early-Ripening Blueberries In Florida, Curtis O. Nelms, Michael L. Avery, David G. Decker

Vertebrate Pest Conference Proceedings: 14th (1990)

Bird damage to early-ripening Florida blueberries was estimated to be approximately 17% in 1988 (2 sites) and ranged from 17% to 75% in 1989 (3 sites) when a late winter freeze severely reduced expected yield. Monetary loss due to bird damage in 1989 may have exceeded $4500/ac at one site. In Florida, birds appear to have a significant impact on the early season fresh market blueberry industry. The problem is likely to worsen as the planting of high-value, early-ripening varieties spreads to other parts of the state and ripening times overlap with wintering frugivorous birds.

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Bird Problems In New Zealand–Methods Of Control, Peter C. Nelson Mar 1990

Bird Problems In New Zealand–Methods Of Control, Peter C. Nelson

Vertebrate Pest Conference Proceedings: 14th (1990)

New Zealand horticulturists are experiencing increasing damage to a variety of crops from a number of introduced bird species. With the advent of the increasing problem there is a need for carefully planned control operations most of which, by necessity, will be carried out by the growers themselves. This means that a variety of baits and toxins is currently being evaluated for control purposes. Growers are being trained in the use of those toxins as well as how to get more effective use from a range of bird-scare devices. Control agencies continue to carry out control of certain bird species …

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