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Cougar Attacks On Humans: An Update And Some Further Reflections, Paul Beier Mar 1992

Cougar Attacks On Humans: An Update And Some Further Reflections, Paul Beier

Vertebrate Pest Conference Proceedings: 15th (1992)

I examined historical records of unprovoked attacks by cougars on humans in the U.S. and Canada during 101 years (1890-1990). There were 9 attacks resulting in 10 human deaths and at least 44 nonfatal attacks. In a recent paper, I listed these attacks and discussed them in considerable detail (Beier 1991). Although extremely rare, attacks on humans have increased markedly in the last 2 decades, during which cougar numbers and human use of cougar habitats have increased. There is no substantial evidence that habituation underlies this increase in attacks. The data provide weak support for the notion that an attacking …


The Most Dangerous Pest: "Homo Environmentals", Robert James Bidinotto Mar 1992

The Most Dangerous Pest: "Homo Environmentals", Robert James Bidinotto

Vertebrate Pest Conference Proceedings: 15th (1992)

I speak of that insatiable predator, Homo environmentalus. This predator is a subspecies of homo sapiens, of which I observe several examples present. For the past several years, under special funding by Reader's Digest, I have made a special study of this pest, also known by his more familiar name of "environmentalist activist."


Problems With Management Of A Native Predator On A Threatened Species: Raven Predation On Desert Tortoises, William I. Boarman Mar 1992

Problems With Management Of A Native Predator On A Threatened Species: Raven Predation On Desert Tortoises, William I. Boarman

Vertebrate Pest Conference Proceedings: 15th (1992)


Common ravens (Corvus corax) are a major predator on the threatened desert tortoise (Gopherus [=Xerobates] agassizii). Large numbers of juvenile tortoise shells have been found beneath known raven nests and perches; many shells that show evidence consistent with raven predation have been found sporadically throughout the range of the tortoise; significant proportional decreases in juvenile size/age class distributions have been identified; and people have observed ravens killing, carrying, and consuming juveniles. In 1988 the U. S. Bureau of Land Management initiated a process to evaluate, design, and implement a program to reduce raven predation …


Review Of Research On Control Of Bird Pests In Australia, Mary Bomford Mar 1992

Review Of Research On Control Of Bird Pests In Australia, Mary Bomford

Vertebrate Pest Conference Proceedings: 15th (1992)

The most significant damage inflicted by birds in Australia is to germinating cereal and to ripening sunflower and fruit crops. The main pests are several native psittacine and corvid species, silvereyes (Zosterops lateralis) and European starlings (Sturnus vulgaris). The economic cost of damage is largely unquantified. While losses to industries as a whole are often low, losses to individual growers may be severe, and losses are distributed patchily in space and time. Shooting is the most widely practiced and most ineffective bird control technique used in Australia. Despite the high numbers of birds killed, damage persists, …


A Role For Fertility Control Wildlife Management In Australia?, Mary Bomford, Peter O'Brien Mar 1992

A Role For Fertility Control Wildlife Management In Australia?, Mary Bomford, Peter O'Brien

Vertebrate Pest Conference Proceedings: 15th (1992)

Increasing community awareness of the moral and animal welfare issues associated with conventional pest animal control has focused interest on non-lethal alternatives, such as fertility control. In Australia, animal welfare organizations have proposed fertility control as a solution to pest problems with feral horses and kangaroos. Wildlife damage control achieved by non-lethal, non-toxic and humane means would have wide appeal and application. Importantly, assessments of effectiveness must focus on damage control, rather than fertility control, per se. Most tests of fertility control drugs and techniques examine effects on reproduction, rather than on population dynamics. Many tests and models have not …


Rodent Control In The Conservation Of Endangered Species, A.P. Buckle, M.G.P. Fenn Mar 1992

Rodent Control In The Conservation Of Endangered Species, A.P. Buckle, M.G.P. Fenn

Vertebrate Pest Conference Proceedings: 15th (1992)

The commensal rodent pest species have spread from their ancestral homes in Asia to inhabit many natural ecosystems worldwide. The introduction of these exotics has often had a significant effect on endemic plant and animal species but their impact has, perhaps, been most severe on off-shore and oceanic islands where nesting birds, insects, terrestrial molluscs, reptiles and amphibians are all vulnerable. Conservationists have used a variety of control approaches either to reduce or eliminate the pressure of competition and predation exerted by introduced rodents on island populations of endangered species. Successful projects have involved a sequence of carefully-planned operations. Firstly, …


Toxicity Of Compound 1080 To Magpies And The Relationship Of Dose Rates To Residues Recovered, Richard J. Burns, Guy E. Connolly Mar 1992

Toxicity Of Compound 1080 To Magpies And The Relationship Of Dose Rates To Residues Recovered, Richard J. Burns, Guy E. Connolly

Vertebrate Pest Conference Proceedings: 15th (1992)

The acute oral LD50 of Compound 1080 to magpies was estimated at 1.78 mg/kg indoors, 1.91 mg/kg outdoors in summer, and 2.30 mg/kg outdoors in winter. Postmortem 1080 residues were detected in 75 of 76 treated birds. Higher doses yielded higher 1080 residues. Within dose levels, birds surviving longer carried lower residues. In a separate test, an average residue of 0.09 ppm was found in 8 birds treated at 1.59 mg/kg and euthanized 24 h post dosing. The adjusted dietary LC50 of Compound 1080 to magpies tested indoors was estimated at 16 ppm. During LC50 tests, the …


Developing A Strategy Of Predator Control For The Protection Of The California Least Tern: A Case History, Peter H. Butchko, Maynard A. Small Mar 1992

Developing A Strategy Of Predator Control For The Protection Of The California Least Tern: A Case History, Peter H. Butchko, Maynard A. Small

Vertebrate Pest Conference Proceedings: 15th (1992)

In recent years, predation has been determined to be a seriously limiting factor in the reproduction of the endangered California least tern (Sterna antillarum browni) at many of its nesting colonies. Among them is a major colony at Camp Pendleton Marine Corps Base near Oceanside, CA. Early efforts to control predation were limited in effectiveness. In 1988, the U.S. Department of Agriculture, Animal Damage Control Program was contracted to provide control of mammalian and avian predators. The development of the successful strategy that has evolved over four years is discussed, with emphasis on the development and application of …


Field Efficacy Evaluation Of Diphacinone Paraffin Bait Blocks And Strychnine Oat Groats For Control Of Forest Pocket Gophers (Thomomys Spp.), D.L. Campbell, J.P. Farley, P.L. Hegdal, R.M. Engeman, H.W. Krupa Mar 1992

Field Efficacy Evaluation Of Diphacinone Paraffin Bait Blocks And Strychnine Oat Groats For Control Of Forest Pocket Gophers (Thomomys Spp.), D.L. Campbell, J.P. Farley, P.L. Hegdal, R.M. Engeman, H.W. Krupa

Vertebrate Pest Conference Proceedings: 15th (1992)

The effectiveness of bait and the effectiveness of operational baiting were both evaluated for controlling forest pocket gophers (Thomomys spp. ) with strychnine oat groat bait and diphacinone paraffin block bait. Radio-telemetry monitoring and recovery of pocket gophers showed that control of individual pocket gophers 1 month after baiting was 72% for strychnine bait and 62% for diphacinone bait. Reduction in pocket gopher activity from operational baiting was based on censusing activity in sample plots. After 1 month the reduction in activity was 61% for strychnine oats and 36% for diphacinone blocks. Bait blocks implanted with radio transmitters were …


Administrative Procedures And Contracts For Vertebrate Pest Programs, Bruce A. Colvin, Curtis A. Meininger, Michael J. Grealy Mar 1992

Administrative Procedures And Contracts For Vertebrate Pest Programs, Bruce A. Colvin, Curtis A. Meininger, Michael J. Grealy

Vertebrate Pest Conference Proceedings: 15th (1992)

A proactive (rather than reactive) approach to rodent control includes effective planning, administration, and coordination. Centralized coordination, detailed scheduling, and well-defined contract specifications provide a solid basis for managing an integrated pest management program. Documentation and data management help to ensure cost effective and efficient operations. The ability to work with people and bureaucracies is essential for the science of rodent control to be applied effectively in real world situations and for vertebrate pest programs to succeed.


Conference Participants Mar 1992

Conference Participants

Vertebrate Pest Conference Proceedings: 15th (1992)

Participants came from 32 states, the District of Columbia, and from 11 other countries for a total of 327 registered attendees. The wide representation from the United States and countries throughout the world contributed to the success of the conference by providing a highly diversified group for the exchange of information on research progress, technological advances, management strategies, new products and materials, prevailing management philosophies, the protection of endangered species, and a range of other vertebrate pest topics.


Development Of Rodent Control Technology For Confined Swine Facilities, Robert M. Corrigan, Cheryl A. Towell, Ralph E. Williams Mar 1992

Development Of Rodent Control Technology For Confined Swine Facilities, Robert M. Corrigan, Cheryl A. Towell, Ralph E. Williams

Vertebrate Pest Conference Proceedings: 15th (1992)

This paper discusses the development of site-specific baiting technology for controlling the house mouse (Mus musculus) in confined swine facilities utilizing specific rodenticide formulations, bait stations, and baiting strategies. Behavioral research was also conducted to identify primary nesting and travel activities of mice within grower-finishing units. The rodenticide bromadiolone in a block formulation was found to be effective in most baiting trials, and provided resistance to the harsh environment of the swine facility and the necessary versatility for securing baits to minimize hazards to swine. A commercially available tamper resistant bait station was found to be effective for …


Coyote Control To Protect Endangered San Joaquin Kit Foxes At The Naval Petroleum Reserves, California, Brian L. Cypher, Jerry H. Scrivner Mar 1992

Coyote Control To Protect Endangered San Joaquin Kit Foxes At The Naval Petroleum Reserves, California, Brian L. Cypher, Jerry H. Scrivner

Vertebrate Pest Conference Proceedings: 15th (1992)

We investigated the effectiveness of a coyote (Canis latrans) control program implemented to increase numbers of endangered San Joaquin kit foxes (Vulpes macrotis mutica) at the Naval Petroleum Reserves in California (NPRC). Between 1980 and 1985, the kit fox population on NPRC declined approximately 66% while coyote abundance apparently increased. Coyote predation was identified as the primary cause of mortality for kit foxes. From 1985 to 1990, the U. S. Department of Energy (DOE) sponsored a program to kill coyotes with the objective being to reduce predation on kit foxes and increase fox numbers. Control methods …


Sterilants For Managing The Populations Of Red-Winged Blackbirds (Agelaius Phoeniceus), Andrew Cyr, Diane Lacombe Mar 1992

Sterilants For Managing The Populations Of Red-Winged Blackbirds (Agelaius Phoeniceus), Andrew Cyr, Diane Lacombe

Vertebrate Pest Conference Proceedings: 15th (1992)

Male Red-winged blackbirds (Agelaius phoeniceus) being gregarious, and causing heavy damage to corn crops in the northeast, including southern Québec and Ontario, sterilization has been studied as a mean's to manage their populations. With chemosterilants (thiotepa and Omitrol®) tested, year to year variations in reproductive success occurs. The spermatogenesis is disrupted, but the overall effect is not specific. Biosterilisation with 10.0 μg doses of GnRH-analogue hormones is more specific, and the spermatogenesis is disrupted for at least a month, but several spaced injections were required. No field trials have been done yet.


Unmasking Mascall's Mouse Traps, David C. Drummond Mar 1992

Unmasking Mascall's Mouse Traps, David C. Drummond

Vertebrate Pest Conference Proceedings: 15th (1992)

Twelve mouse traps described and figured by Leonard Mascall in 16th Century England are illustrated and interpreted afresh. Special attention is given to one that is also depicted on the Merode altarpiece, an important 15th Century Dutch painting. Since Mascall's era many of his mouse traps have virtually disappeared. Others have been made more effective by various design changes, including the incorporation of small powerful helical springs and improved release mechanisms, and by the greater use of wire mesh and sheet metal.


Toxic Bait And Baiting Strategies For Feral Cats, Charles T. Eason, David R. Morgan, B. Kay Clapperton Mar 1992

Toxic Bait And Baiting Strategies For Feral Cats, Charles T. Eason, David R. Morgan, B. Kay Clapperton

Vertebrate Pest Conference Proceedings: 15th (1992)

To improve feral cat control we developed a dry pelleted toxic bait and evaluated the potential of lures. A polymer fish meal bait was preferred by cats from a range of bait types tested. L-alanine further increased bait acceptance by cats in pen trials and catnip may have the potential to increase field acceptance and target specificity. An oral LD90 of 0.38 mg/ kg was established for sodium monofluoroacetate (1080) in feral cats voluntarily eating surface-loaded baits. Acute toxicity to cats of warfarin, cholecalciferol, and gliftor was tested. However, because the cat proved highly sensitive to 1080, we recommend …


An Integrated Approach To The Management Of Urban Canada Goose Depredations, Steven D. Fairaizl Mar 1992

An Integrated Approach To The Management Of Urban Canada Goose Depredations, Steven D. Fairaizl

Vertebrate Pest Conference Proceedings: 15th (1992)

Canada geese (Branta canadensis) in the Reno-Sparks, Nevada urban area have become a problem of increasing significance. Nuisance complaints from city parks, golf courses, and housing developments augment the bird hazard to aircraft operations at the local airport. Eleven goose collisions with commercial aircraft, between January 1986 and April 1989, caused $250,000 in structural damages but no injuries or loss of human life. The Federal Aviation Administration required action be taken to reduce the hazard if airport certification was to continue. A multi-agency task force was formed to develop and implement an integrated pest management plan. Population surveys …


Front Matter And Contents Mar 1992

Front Matter And Contents

Vertebrate Pest Conference Proceedings: 15th (1992)


Contents:


A Review Of The Results From Laboratory Tests Of Some Rodenticides Against Eight Rodent Species, J.E. Gill Mar 1992

A Review Of The Results From Laboratory Tests Of Some Rodenticides Against Eight Rodent Species, J.E. Gill

Vertebrate Pest Conference Proceedings: 15th (1992)

The susceptibility of eight rodent species to a range of widely used and candidate rodenticides was determined in laboratory feeding tests. No choice and choice tests were used to assess toxicity and effect on palatability of the rodenticides to Meriones shawi (Shaw's gerbil), Arvicanthis niloticus (Nile rat), Acomys cahirinus (Egyptian Spiny mouse), Mastomys natalensis (Multimammate rat), Sigmodon hispidus (Cotton rat), Rattus exulans (Polynesian rat), and R. rattus (Ship rat) which responded differently to each chemical. The results of these tests suggest possible rodenticides suitable for control of each species. Field trials are now needed to assess the effectiveness of these …


Urban Crow Roosts In California, W. Paul Gorenzel, Terrell P. Salmon Mar 1992

Urban Crow Roosts In California, W. Paul Gorenzel, Terrell P. Salmon

Vertebrate Pest Conference Proceedings: 15th (1992)

We reviewed the historical and current status of the American crow (Corvus brachyrhynchos), urban crow roosts and control efforts in California. Crows aggregate in traditional winter roosting areas. In the late 1930s most crows in California roosted in the Sacramento Valley in rural locations. Crow roosts were not a concern except for potential damage to adjacent farmlands. From the 1960s through 1980s crows colonized urban areas for nesting and winter roosting. A phone survey of vertebrate pest management officials indicated all known roosts were in urban areas, with most occurring in the Sacramento Valley. From 1970 to 1989 …


Metoclopramide Hydrochloride Did Not Prevent 1080-Induced Vomiting In Coyotes, Jeffrey S. Green Mar 1992

Metoclopramide Hydrochloride Did Not Prevent 1080-Induced Vomiting In Coyotes, Jeffrey S. Green

Vertebrate Pest Conference Proceedings: 15th (1992)

Vomiting is a characteristic, although undesirable effect when using Compound 1080 (sodium monofluoroacetate) as a method of predator control for coyotes. Compound 1080 meat baits with (treatment) and without (control) an antiemetic, metoclopramide hydrochloride (MH), were fed to captive coyotes to determine whether MH would prevent vomiting. All treatment and control animals died as a result of consuming the 1080 bait with no difference between the groups in time from bait consumption to death. There was no significant difference between the number of treatment and control animals that vomited after consuming the baits. Likewise there was no difference between the …


Reinfestation Of Bandicota Bengalensis (Gray) In Irrigated Field Habitat, B.K. Guruprasad Mar 1992

Reinfestation Of Bandicota Bengalensis (Gray) In Irrigated Field Habitat, B.K. Guruprasad

Vertebrate Pest Conference Proceedings: 15th (1992)

Bandicota bengalensis, a predominant species inhabiting irrigated fields is a potential pest on agricultural crops and is known to live in extensive burrow systems. The burrow opening covered with mud which is an indicator of its activity seems to be discontinuous. An analysis of burrow systems and their occupations indicated reuse of abandoned burrow systems by new entrants. A study simulated in semi-natural conditions supported the view that there is occupation of old burrows by new immigrants. Non-effective barriers; and availability of Panicum repens on bunds, a food alternative may support the population influx. Availability of old burrow systems …


California Ground Squirrel Field Efficacy Study Using 0.005% Chlorophacinone Bait, Brent Hazen, Richard M. Poche Mar 1992

California Ground Squirrel Field Efficacy Study Using 0.005% Chlorophacinone Bait, Brent Hazen, Richard M. Poche

Vertebrate Pest Conference Proceedings: 15th (1992)

A field efficacy study was completed using Wilco Ground Squirrel Bait (containing 0.005% chlorophacinone) to control California ground squirrels (Spermophilus beecheyi) in Madera County, California. Bait was applied in plastic stations at the rate of 2 lbs. per station. Two plots with buffer zones were treated (about 11.5 acres each). Visual and burrow counts were used as the census indices to determine field efficacy. Pretreatment and posttreatment census observations were conducted over three days pretest and three days posttreatment. Efficacy after 21 days was 94.4% for plot T-l and 100% on plot T-2 using visual counts. Burrow count …


Vertebrate Pesticides No Longer Registered And Factors Contributing To Loss Of Registration, William W. Jacobs Mar 1992

Vertebrate Pesticides No Longer Registered And Factors Contributing To Loss Of Registration, William W. Jacobs

Vertebrate Pest Conference Proceedings: 15th (1992)

Many pesticide chemicals once used to control vertebrate pests are no longer registered in the U.S. Changes in pesticide laws and regulations have played a major role in the loss of vertebrate pesticides, but relatively few products, uses, or compounds have been lost because the U.S. Environmental Protection Agency (EPA) determined that they were too hazardous to be registered. Most canceled products, use patterns, and chemicals have been lost because their registrants abandoned them, choosing not to pay the fees or data development costs necessary to maintain registrations. Pesticide users or other interested parties may be able to "save" a …


Evaluations Of Aversive Agents To Increase The Selectivity Of Rodenticides, With Emphasis On Denatonium Benzoate (Bitrex®) Bittering Agent, Dale E. Kaukeinen, Alan P. Buckle Mar 1992

Evaluations Of Aversive Agents To Increase The Selectivity Of Rodenticides, With Emphasis On Denatonium Benzoate (Bitrex®) Bittering Agent, Dale E. Kaukeinen, Alan P. Buckle

Vertebrate Pest Conference Proceedings: 15th (1992)

Aversive agents are proposed as potential additives to rodenticides to increase selectivity to the target species. Examples of various aversive agent categories are given, including odorants, tastants, and emetics, with examples of evaluations. Tastant additives have been found that do not interfere with rodenticidal efficacy. Denatonium benzoate (commercially available as Bitrex®) is an intensely bitter but non-toxic substance, being increasingly used to adulterate common household materials to reduce the potential risks involved with accidental exposures. No known prior research results have been published concerning the incorporation of Bitrex in rodenticides. Rate determination studies utilizing different rodenticidal formulations were conducted. A …


The Field Rat Control Campaign, Chiapas, Mexico, Gillian E. Key, Romeo De La Piedra Constantino Mar 1992

The Field Rat Control Campaign, Chiapas, Mexico, Gillian E. Key, Romeo De La Piedra Constantino

Vertebrate Pest Conference Proceedings: 15th (1992)

The Secretariat for Rural Development of the State Government of Chiapas, southern Mexico, has been charged with conducting a campaign against the field rat which began in February 1991. Four areas were identified as key sites for the campaign benefiting 3,355 farmers in a total area of 8,000 ha and an initial budget of approximately $500m Mexican pesos (US $170,000). The major crops for which damage is reported are maize, sugar cane and cacao. The term “field rat” is a general one encompassing any rodent causing damage to field crops and in Chiapas probably covers a variety of species; no …


Nontarget Hazards Associated With Egg Baits Used To Control Corvid Depredations On Endangered California Least Tern Eggs At Camp Pendleton, California—1990 (Abstract Only), C. Edward Knittle Mar 1992

Nontarget Hazards Associated With Egg Baits Used To Control Corvid Depredations On Endangered California Least Tern Eggs At Camp Pendleton, California—1990 (Abstract Only), C. Edward Knittle

Vertebrate Pest Conference Proceedings: 15th (1992)

Several small nesting colonies of the endangered California least tern (Sterna antillarum browni) remain along the California coast. The largest of these is located on Camp Pendleton Marine Base in southern California. Many forms of disturbance have apparently contributed to the decline of this tern species, including corvid, primarily raven (Corvus corax), predation on the eggs. Efforts to eliminate corvid predation have primarily focused on shooting offending birds; this method is selective, but it has inherent public safety problems. In 1988, biologists from the Denver Wildlife Research Center (DWRC) and the U.S. Navy, in cooperation with …


Laboratory Studies Of More Durable Baits For Controlling Pocket Gophers, Ling Ling Lee, Walter E. Howard, Rex E. Marsh Mar 1992

Laboratory Studies Of More Durable Baits For Controlling Pocket Gophers, Ling Ling Lee, Walter E. Howard, Rex E. Marsh

Vertebrate Pest Conference Proceedings: 15th (1992)

A laboratory study of 68 Botta's pocket gophers (Thomomys bottae) was carried out to compare the preference for 20 different nontoxic baits and the preference and efficacy of 14 different toxic baits. All baits were designed to be more durable (i.e., longer lasting) than loose grain baits to increase the chance that one baiting might successfully control any new gopher invader that moved into an unoccupied burrow system. Bait types ranged from pure paraffin cubes, polyethylene bags of grain bait (plain or coated with paraffin and carrot powder), and paraffin grain baits (3.4 g and 10 g). Wide …


Electronic Frightening Devices For Reducing Coyote Predation On Domestic Sheep: Efficacy Under Range Conditions And Operational Use, Samuel B. Linhart, Gary J. Dasch, Richard B. Johnson, Jerry D. Roberts, C. Joe Packham Mar 1992

Electronic Frightening Devices For Reducing Coyote Predation On Domestic Sheep: Efficacy Under Range Conditions And Operational Use, Samuel B. Linhart, Gary J. Dasch, Richard B. Johnson, Jerry D. Roberts, C. Joe Packham

Vertebrate Pest Conference Proceedings: 15th (1992)


A portable 12-v battery-operated coyote frightening device was developed for reducing coyote predation on sheep and evaluated on fenced pasture farm flock operations (1979-1982). In 1986, the final experimental model consisted of a PVC case, a timer, a blinking strobe light, and a warbling type siren that was activated for 7-10 seconds at about 6-7 minute intervals throughout the night. The devices were generally suspended about 2 m above the ground and were activated at dusk by a photocell and turned off about 2 hours after dawn by a timer. Here we report tests on high mountain summer sheep ranges …


Scarecrows And Predator Models For Frightening Birds From Specific Areas, Rex E. Marsh, William A. Erickson, Terrell P. Salmon Mar 1992

Scarecrows And Predator Models For Frightening Birds From Specific Areas, Rex E. Marsh, William A. Erickson, Terrell P. Salmon

Vertebrate Pest Conference Proceedings: 15th (1992)

Scarecrows and raptor models are fairly common traditional methods of attempting to frighten unwanted birds. Their effectiveness depends on the conditions under which they are used and the unwanted bird species involved. Best results are obtained from those that are most lifelike and have motion. When coupled with loud startling sounds or recorded distress calls their effectiveness is generally enhanced. Habituation by at least some birds is inevitable so the duration of effectiveness diminishes with time. It is essential to know what works best in a given situation so those methods can be employed to achieve maximum efficiency. An understanding …