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Proceedings: Third Vertebrate Pest Conference -- Frontmatter & Contents

Vertebrate Pest Conference Proceedings: 3rd (1967)

Sponsored by the California Vertebrate Pest Technical Committee

Maynard W. Cummings - Chairman

Richard H. Dana - Vice Chairman

Rex E. Marsh - Secretary-Treasurer

GENERAL CHAIRMAN OF CONFERENCE - Maynard W. Cummings, Assistant State Director, Agricultural Extension Service, University of California, Davis, California. VICE-CHAIRMAN OF CONFERENCE - Richard H. Dana, Vertebrate Pest Control Specialist, California Department of Agriculture, Sacramento, California. PROGRAM CHAIRMAN - Charles C. Siebe, Vertebrate Pest Control Specialist, California Department of Agriculture, Sacramento, California. PUBLICITY CHAIRMAN - Rex E. Marsh, Associate Specialist, Department of Animal Physiology, University of California, Davis, California. ARRANGEMENTS CHAIRMAN - Jerry P. Clark, Agricultural …

Aircraft As A Means Of Baiting Ground Squirrels, Rex E. Marsh

Vertebrate Pest Conference Proceedings: 3rd (1967)

Aircraft might soon become an important tool for baiting ground squirrels (Citellus beecheyi beecheyi and C. b. fisheri) on California rangeland. Until recently, almost all squirrel control has been conducted by the hand-baiting method, with grain bait scattered from horseback in spoon-size amounts near squirrel burrows. Ground squirrels are considered a major pest of rangeland in many parts of the West. They not only compete with livestock for forage but also are responsible for substantial losses to cereal and other crops. The magnitude of the problem is exemplified by the fact that, in California alone, over 6,000,000 gross acres of …

Problems In County-Wide Rodent Control Programming, Loring White

Vertebrate Pest Conference Proceedings: 3rd (1967)

Vertebrate pest control is recognized and sanctioned as a legitimate function of county government in California, not only by statute but also by a century of tradition. This is an anomaly. Ordinarily, regulatory agricultural pest control programs are part of our plant quarantine system, undertaken against newly introduced pests or those which are not of common occurrence. Programs against vertebrate pests, on the other hand, are carried on where the species involved are common, usually are abundant and often are indigenous. The reason for this lies buried in a bit of history that is very pertinent to my subject.

The Current Status Of Plague In California, Keith F. Murray

Vertebrate Pest Conference Proceedings: 3rd (1967)

At the first Vertebrate Pest Control Conference in 1964, I traced the history of plague control in California and outlined a revised approach, based on newer concepts of plague ecology. In our state of relative ignorance, this required a number of unproved assumptions about plague occurrence in California that verged on crystal ball gazing. These were principally that (1) plague persists in relatively resistant rodent species in certain favorable locations, (2) ground squirrels and chipmunks experience periodic epizootics, but are not permanent reservoirs, (3) plague "foci" of the past were merely sites of conspicuous epizootics, they did not necessarily correspond …

The Current Status Of Wild Animal Rabies In California, George L. Humphrey

Vertebrate Pest Conference Proceedings: 3rd (1967)

During the 15-years 1952-1966, a total of 3504 cases of animal rabies were reported in California, an average of over 230 cases annually (Table 1). Of these 3504 cases, 2255 or nearly 65 percent were reported in wildlife species. An estimate sometimes used is that for every reported or recognized case of wild animal rabies, 10 cases probably occurred without recognition. Using the foregoing "rule-of-thumb", it can be hypothesized that during the 15-years 1952-1966, an estimated 22,600 or more cases of wildlife rabies occurred in California. The addition of the over 1200 cases of rabies reported in domestic animals during …

Good Practice In Vertebrate Pest Control, Philip J. Spear

Vertebrate Pest Conference Proceedings: 3rd (1967)

Good practice in pest control is a responsibility of several elements in our democratic, free-enterprise society. Most notably, these are: (1) the general public, (2) responsible government agencies and (3) industry. Before I comment about the responsibilities of each of these three groups, let me tell you about the work of structural pest control operators and their interests in vertebrate pest control. The pest control industry which I discussed in detail at the Second Vertebrate Pest Control Conference (1) continues to grow and expand its fields of activity. At the present time, it is our estimate (2) that 26,700 persons …

Review Of Animal Repellents, Jack F. Welch

Vertebrate Pest Conference Proceedings: 3rd (1967)

A review of the literature on this subject reveals there is considerable confusion regarding the meaning of the word "repellent" as it relates to animal control. Some people make a liberal interpretation and include any material or device that will alter the pattern of activity of an animal through response to sight, sound, taste, odor, or touch. Although such an interpretation may be valid, for this paper I would like to confine my discussion to "chemical repellents" -- materials that, when applied to seeds, plants, or other materials being damaged by animals, will reduce depredation through taste, odor, or possibly …

Animal Control - Progress, Problems And Professionalism, Robert M. Sutton Jr.

Vertebrate Pest Conference Proceedings: 3rd (1967)

I want to take some liberty with my title as it is rather general. Specifically, I want to discuss some matters of mutual concern, and I will touch lightly upon our Division's activities and the status of our reorganization and redirection. In so doing, I do not propose to rehash the several talks that have been previously given and the papers written on what's new in animal control. Rather, I shall use this opportunity to examine a few problems that confront our Division, and in many cases, that confront everyone concerned with vertebrate pest control. We are now, in a …

Rats, Bombs, And Paradise - The Story At Eniwetok, William B. Jackson

Vertebrate Pest Conference Proceedings: 3rd (1967)

At Eniwetok Atoll in the Marshall Islands, rats have been involved in an intriguing story. Polynesian rats were probably the only rodents present until after World War 11 when roof rats were brought in along with supplies and equipment for the atomic test program in the late 40's or early 50's. Some islets of the atoll, originally covered with coconut plantations, were denuded by heat, shock, and tidal waves following the detonation of devices. Initially radiation levels were high, but radioactive decay and dilution reduced the radiation hazard, and today the background radiation is well within the safe range. Many …

Blackbirds - Depredation, Research And Control In Ohio And The Midwest, Thomas M. Stockdale

Vertebrate Pest Conference Proceedings: 3rd (1967)

The earliest settlers in Ohio and the Midwest suffered losses to birds. First it was animal losses to birds of prey, then crop losses to passenger pigeons. Today it is blackbirds! In 1900, F. E. L. Beal conducted an analysis of the digestive tracts of blackbirds collected in the Midwest and found that the preferred food in the summer months was soft seeds. A similar study which I conducted on redwinged blackbirds in 1959 showed that 90% of their diet was composed of soft seeds, primarily milk and dough stage corn during the late summer and early fall. Presently we …

Blackbird Damage Control With Chemical Frightening Agents, Paul P. Woronecki, Joseph L. Guarino, John W. De Grazio

Vertebrate Pest Conference Proceedings: 3rd (1967)

Birds involved in damage or nuisance situations also have beneficial qualities, and most species are protected by State and Federal laws. Programs designed to alleviate bird problems, particularly those involving blackbirds, should first seek to discourage the birds from using problem areas and not to eliminate populations by direct reductional control. Habitat manipulation and mechanical frightening devices are useful techniques for discouraging bird activity, but certain chemical frightening agents have distinct advantages in some situations. We have found these agents particularly effective when used to control blackbird damage. Chemical frightening agents can be divided into two groups, the lethal and …

Measuring Bird Damage To Corn, John T. Linehan

Vertebrate Pest Conference Proceedings: 3rd (1967)

When corn is damaged by birds, kernels are eaten or "milked" and the affected ears are left with fewer intact kernels. The resulting damage, or loss, can be expressed in terms of the number, weight, volume, or value of the kernels that were removed or pecked. Assessment of loss thus frequently entails measuring, counting, or estimating from evidence of kernels lost. Estimates of loss resulting from the activity of birds should express the difference in value between a crop grown under the conditions that prevail and the value under the hypothetical condition of no adverse bird activity. To offset the …

Blackbird Behavior, Gordon W. Boudreau

Vertebrate Pest Conference Proceedings: 3rd (1967)

A knowledge and understanding of a bird's habits and behavior patterns is prerequisite to any intelligent approach toward solving problems created by that species. This also applies to associated species commonly observed with it. Since my subject today is blackbirds I will confine my observations to species in this group, particularly red-winged blackbirds. The Red-Winged Blackbird, (Agelaius phoeniceus) is numerically and economically the most important. Several sub-species or races are recognized and in California the most important of these is the Bi-colored Blackbird, (A. p. californica). The ranges of subspecies commonly overlap, particularly in the Southeast, and field identification is …

Population Control Of Herring Gulls By The Embryocide, Sudan Black*, David K. Wetherbee

Vertebrate Pest Conference Proceedings: 3rd (1967)

The purpose of this experiment was to test the application of a biochemical method proposed to control the hatching of herring gull (Larus argentatus) eggs in a wild population. Sophistication was considered in terms of practicality, effectiveness, selectivity, economy, humaneness, remote application and hazards to and in the environment. The herring gull, which at the turn of the century was unknown as a breeding bird in northeastern United States, now nests abundantly along the Atlantic coast as far south as Virginia. Its phenomenal increase in numbers has resulted in conflicts with several human interests, including competition with other desirable nesting …

Control Of Nuisance Pests In Suburbia, Howard A. Merrill

Vertebrate Pest Conference Proceedings: 3rd (1967)

To a rancher or high-rise apartment dweller, problems with vertebrate pests in suburbia may seem insignificant. But when one stops to consider that last year over 2 million acres of farmland were converted into urban and industrial use, then it takes a different perspective. Some mammals are protected—game animals and fur bearers are usually protected by Fish and Game Departments. Cottontail rabbits, deer, and tree squirrels are examples of game animals, and muskrats, foxes, badgers, and raccoons are examples of fur bearers. In California a number of birds and mammals have no protection; these are English sparrows, American or black-billed …

Birds And Airports, Erwin W. Pearson

Vertebrate Pest Conference Proceedings: 3rd (1967)

For all practical purposes, research in this country on the problem of bird hazards to aircraft began in 1960 with the crash of an Electra turboprop that carried 62 people to their deaths and was attributed to ingestion of starlings into the engines. In this paper I intend to review the problem and present some of the answers found by investigators in this country and, to lesser extent, abroad. The discussion will be roughly divided into two parts: 1) what: causes the problem, when, and where; and 2) what has been and is being done at airfields to reduce it. …

Role Of The Agricultural Extension Service In Vertebrate Pest Control, Marvin D. Davis

Vertebrate Pest Conference Proceedings: 3rd (1967)

Frankly, I often wonder what our role is in vertebrate pest control. It seems to me that we in A.E.S, are frequently treading in the "twilight zone" of pest control. This is because of the wide diversity of problems which arise within an area such as I represent. I feel it is most significant that our county was invited to cover the role of A.E.S. in vertebrate pest control and discuss the tremendous variations and considerations necessary to serve an urban/semi-urban to rural county. Those of you familiar with San Mateo County readily recognize the potential problems due to population …

Starling Control In Livestock Feeding Areas, Richard R. West, Jerome F. Besser, John W. Degrazio

Vertebrate Pest Conference Proceedings: 3rd (1967)

The Denver Wildlife Research Center has been investigating methods to combat starling (Sturnus vulgaris) problems at livestock feeding areas since 1960. A variety of chemicals, baits, and methods of bait placement have been tested. This paper summarizes these investigations.

CHEMICALS TESTED About 500 chemicals have been screened for toxic and stupefacient effects on starlings. Although several chemicals have been found that immobilize starlings in the laboratory, they have been largely ineffective in the field; most starlings regurgitate the treated baits, and seldom have substantial numbers been affected. Of the toxicants screened, four compounds, TEPP, DRC-632, DRC-1327, and DRC-1339, have shown …

The Summer European Starling Problem In Tulare County, William R. Clark

Vertebrate Pest Conference Proceedings: 3rd (1967)

Summer starlings (Sturnus vulgaris) are known to have caused damage to the agricultural industry of Tulare County since 1960. At this time the first confirmed appreciable damage to grapes occurred. Since that year the threat has grown considerably as populations have increased. Annual monetary losses have fluctuated but damage has increased steadily and many losses are going unreported or unevaluated by the growers. Known total monetary losses in Tulare County have reached over $28,500.00 in a single summer and the unknown or unrealized losses would probably double this figure. The diversity of crops damaged has mounted steadily, as anticipated, and …

Winter Starling Control With Drc-1339, Paul E. Levingston

Vertebrate Pest Conference Proceedings: 3rd (1967)

Several years ago starling problems in cattle feed lots exploded to economic proportions. In 1964 one northern California feed lot operator reported a loss of $1,000 per day during the winter months. This resulted from daily activity of over a million starlings. Along with consuming and contaminating large amounts of cattle feed, the birds disturbed the cattle and prevented regular feeding habits. This reduced weight gains drastically. To combat what had become a state-wide problem, in 1962 a cooperative program between the California Department of Agriculture, the county agricultural commissioners, the United States Bureau of Sport Fisheries and Wildlife, and …

The Use Of Live Traps To Remove Starlings And Protect Agricultural Products In The State Of Washington, Vincent Bogatich

Vertebrate Pest Conference Proceedings: 3rd (1967)

Much has already been said and written about the use of live traps for the control of starlings in the State of Washington and our efforts have evidently been viewed with interest for we have received letters and questions about our program from all over the world. Our interest in the possibilities of the live trap began back in 1960 when spring and summer surveys revealed a high nesting population and an increasing percentage of bird damage to a very valuable cherry growing industry. This damage was mainly attributable to the local flocks of juvenile starlings. Over the years we …

Winter Starling Control In Idaho, Nevada, And Oregon, Homer S. Ford

Vertebrate Pest Conference Proceedings: 3rd (1967)

This paper is intended to bring you up-to-date on the progress of various winter starling control projects conducted by our Bureau on feedlots in Idaho, Nevada, and Oregon. This report briefly covers the field work accomplished since that reported by the late Mr. H. Nelson Elliott in his paper delivered to the second meeting of your conference held in Anaheim, California, in March 1964. Prior to the winter of 1960-61 we experienced a tremendous build-up of starling populations in feedlot situations throughout the Pacific Northwest. The expanding livestock feeding industry was receiving great economic losses from starlings eating livestock feed …

A Method Of Controlling Jack Rabbits On A Range Rehabilitation Project In California, Frank A. Wetherbee

Vertebrate Pest Conference Proceedings: 3rd (1967)

In recent years the Bureau of Land Management's range rehabilitation program in the high sagebrush areas of northeastern California has included control of sagebrush preceded by the seeding of drought resistant grasses such as crested wheatgrass. Jack rabbit browsing and uprooting of young seedling plants has in many instances severely retarded the establishment of these grasses. Because of this it has become apparent that rabbit reduction in many of these areas is essential if a grass stand is to become established. A comparison of Figures 6 and 7 illustrates the problems jack rabbits can cause to range rehabilitation projects where …

Biotelemetry — Its Use In Vertebrate Control Studies, Wendell E. Dodge

Vertebrate Pest Conference Proceedings: 3rd (1967)

Accurate evaluation of rodent control techniques has always been a laborious undertaking. It generally involves tedious pre- and post-treatment censusing by trapping, marking, track counts, reduction of activity, etc., and results, at best, must necessarily contain a significant amount of speculation by the investigator. The biologist conducting such studies has been constantly harassed by uncontrollable parameters such as trap response, immigration, emigration, predation, disease, and many others. Thus, there has been a pressing need of a more definitive technique for evaluating rodent control trials. During the last decade, a new tool called biotelemetry has become available to the wildlife biologist. …

Rodent Problems On Private Forest Lands In Northwestern California, Jarrold B. Cone

Vertebrate Pest Conference Proceedings: 3rd (1967)

Rodents damage is important to forest management and is adequately described in the literature (Kverno, 1964; Hooven, 1958, 1959; Lawrence, 1958; Isaac, 1943; Kangur, 1954; Tevis, 1956a). It is not the intent of this paper to reiterate the types of damage or the rodents involved; the reader who is interested in this topic is particularly directed to the work of Lawrence, Kverno, and Hartwell (1361). This paper is concerned with the major forest rodent control efforts currently being employed in northwestern California. It will describe the background of literature and investigation from which present practices evolved, the implications that these …

The Status And Use Of Gophacide, Voit B. Richens

Vertebrate Pest Conference Proceedings: 3rd (1967)

Toxicants have been widely used for several decades to reduce numbers of problem animals. The utility of these substances, however, has been limited by hazards to other animals and man, inadequate effectiveness against the target species, and restrictions on use. The ecological complexity of most habitats in which animal control is undertaken requires utilization of new poisons that are less hazardous, more effective, and more specific. Gophacide1, Bayer 38819, 0_, 0-bis(p-chlorophenyl) acetimidoylphosphoramidothioate, is generally favorable in these respects. Tests with Gophacide were initiated at the Denver Wildlife Research Center in late 1961; and more recently, this chemical has also been …

Biological Control Of Vertebrate Pests, Walter E. Howard

Vertebrate Pest Conference Proceedings: 3rd (1967)

This paper briefly introduces the subject of vertebrate pest control, integrates and interprets some important ecological principles of control methodology, and intercalates these discussions with analysis of the biological backlashes and other ecological interactions that may be created whenever troublesome species of vertebrates are controlled by biological means. Insight in this area must be deepened if we are to fulfill our primary objective of learning how to manage a healthy environment in perpetuity. One important merit of biocontrol is that most people accept carefully planned ecological dislocations in nature more readily than they do the repugnant and hazardous aspects of …

Recent Developments In The Control Of Vertebrate Problem Animals In The Province Of The Cape Of Good Hope, Republic Of South Africa, Douglas Hey

Vertebrate Pest Conference Proceedings: 3rd (1967)

In an earlier paper (Hey, 1964 an account was given of the topography and climate of the Cape Province, a description of the vertebrate animals and birds which might be considered to fall in the category of problem animals and the control methods used. The present paper will, therefore, deal with advances in control techniques which have since been made. At this juncture, it would be appropriate to record our sincere appreciation to the Director and Staff of the U.S. Fish and Wildlife Service and particularly to the Senior Officers of the Denver Research Center, District Agents Malcolm Allison and …

Federal Wildlife Importation Regulations: The Why And Wherefore, Joseph P. Linduska

Vertebrate Pest Conference Proceedings: 3rd (1967)

This is a hasty and in many ways superficial review of the motivations that started us in the business of importing new, strange, beautiful, and hopefully useful wildlife. It is a capsuled account of the high cost of ill-advised introductions and of near misses that were avoided thanks to a few individuals who viewed such transplants with skepticism and even alarm. And I have touched also on the highlights of the legislative base from which we now operate in efforts to safeguard agriculture and other values from ravages of exotic wildlife; wildlife that may succeed too well with us and …

Conference Participants

Vertebrate Pest Conference Proceedings: 3rd (1967)

The Third Vertebrate Pest Conference was an enormous success with 265 in attendance, of these, 203 were registered participants. The attendance was made up of individuals having varying interests in vertebrate pest problems including foresters, agriculturalists, conservationists, pest control operators, vector control specialists, health officials, wildlife specialists, product distributors and manufacturers, instructors and researchers from twenty three states plus Washington D. C. and South Africa.