BEHAVIORAL RESPONSE OF CATTLE EGRETS TO POPULATION CONTROL MEASURES IN HAWAII

We monitored behavior of cattle egrets (Bubulcus ibis) during a population control program to reduce egret-aircraft strike hazards from a small heronry near the Hilo, Hawaii, airport. Results verified that attempts to move egrets from undesirable roost sites should be undertaken before nesting begins. Although possibly compounded by previous treatments, our observations also indicate that 1) egrets may abandon a new roost in response to a few dead egrets placed in clear view around the roost, and 2) shooting at egrets as they attempt to land at a traditional feeding site causes long-term avoidance of the area. Rapid repopulation after control indicates that techniques to move roosts and prevent congregations are more likely than population control to resolve problems.

TESTS OF BIRD DAMAGE CONTROL MEASURES IN SUDAN, 1975

The Red-billed Quelea (Quelga quelaa), because of its widespread destruction of grain crops throughout its range in Africa, is one of the most studied and written about granivorous bird species. Less publicized are more local bird pests in Africa which may be equally Important. The Village Weaver, (Ploceus cucullatus), for example, is a pest in many countries, while some other Ploecids with limited destructive habits create local problems. Significant crop losses also occur where there are large populations of Golden Sparrows (Passer luteus), House Sparrows (Passer domesticus), Red Bishops (Euplectes oryx), Doves (Streptopelia spp.), Glossy Starlings (Lamprotornis chalybaeus), Parakeets (Psittacula spp.), and some waterfowl (Mackworth-Praed and Grant, 1952; Pans Manual No. 3, 1974; Park, 1974). Crop losses from local bird pests were reported in early February 1975 to the Sudan Plant Protection Bird Control Unit of the Ministry of Agriculture. A mechanized farm scheme in Khartoum North had large concentrations of Red Bishops roosting in maize and feeding on an early-maturing wheat variety (Mexicana). Small flocks of Golden Sparrows and House Sparrows also were present. Bird damage was clearly visible, especially at the corners and along the edges of the ripening wheatfields. Ground spraying with Queletox (60% a.1. Fenthion) on roosts of the Golden and House Sparrows was conducted along hedge rows of acacia (Acacia mellifera) located at the north end of the farm. Although the spray killed large numbers of roosting birds, damage con- tinued as the wheat matured. Pilot field trials were thus organized to test the effectiveness of other crop protection techniques. Because birds fed throughout many blocks of wheat which matured at different periods, it was felt that several different experiments could be conducted without Interfering with each other. The control techniques Included an acoustical repellent, a chemical repellent, a chemical frightening agent, and a trap. The experiments, conducted from February 7 through February 23, 1975, were not designed as an integrated control operation.

THE CONTROL OF VERTEBRATE PROBLEM ANIMALS IN THE PROVINCE OF THE CAPE OF GOOD HOPE, REPUBLIC OF SOUTH AFRICA

The policy of the Cape Provincial Department of Nature Conservation is based on the concept of "wise management" of wildlife resources. Where crop damage is real, control measures are essential. These, however, must be adapted to the species concerned and applied only where the damage is taking place. Blanket measures which also kill many useful species must be avoided. For this reason, the control of problem animals should be vested in the agency concerned with wildlife conservation.

ANIMAL POPULATION ECOLOGY AND CONTROL FUNDAMENTALS

Expensive, extensive and apparently lethal control measures have been applied against many species of pest vertebrates and invertebrates for decades. In spite of this, few pests have been annihilated, and in many cases the stated goals have become progressively more modest, so that now we speak of saving foliage or a crop, rather than extermination. It is of interest to examine the reasons why animals are so difficult to exterminate, because this matter, of course, has implications for the type of control policy we pursue in the future. Also, it has implications for the problem of evaluating comparatively various resource management strategies. There are many biological mechanisms which could, in principle, enhance the performance of an animal population after control measures have been applied against it. These are of four main types: genetic, physiological, populationa1, and environmental. We are all familiar with the fact that in applying a control measure, we are, from the pest's point of view, applying intense selection pressure in favor of those individuals that may be preadapted to withstand the type of control being used. The well-known book by Brown (1958) documents, for invertebrates, a tremendous number of such cases. Presumably, vertebrates can show the same responses. Not quite so familiar is the evidence that sub-lethal doses of a lethal chemical may have a physiologically stimulating effect on population performance of the few individuals that happen to survive (Kuenen, 1958). With further research, we may find that this phenomenon occurs throughout the animal kingdom. Still less widely recognized is the fact that pest control elicits a populational homeostatic mechanism, as well as genetic and physiological homeostatic mechanisms. Many ecologists, such as Odum and Allee (1950, Slobodkin (1955), Klomp (1962) and the present author (1961, 1963) have pointed out that the curve for generation survival, or the curve for trend index as a function of last generations density is of great importance in population dynamics.

VS - Bovine Tuberculosis (Mycobacterium bovis) Surveillance Standards 11/2001

Bovine tuberculosis (TB) is an infectious and communicable granulomatous disease caused by the acidfast bacilli bacteria of Mycobacterium bovis (M. bovis). It is commonly a chronic, debilitating disease, but occasionally may assume an acute, rapidly progressive course. M. bovisis a widespread zoonosis that is global in magnitude and affects nearly all species of vertebrates (cattle, sheep, goats, pigs, bison, buffalo, and camelids.) Disease is spread by direct contact, inhalation of infected droplets expelled from infected lungs, and ingestion of contaminated feed or milk. In most countries, TB is a notifiable disease. Overall, TB has an important world-wide impact on animal industries and human health. Control measures are based on prevention and eradication. Surveillance is a key element for management of preventions and control programs. Surveillance for TB serves the purpose of enabling Veterinary Services to obtain an accurate picture of the scope of the disease in the US livestock populations; in the event of a disease outbreak, the course TB follows in livestock and wildlife populations for a given area over time; and permits timely intervention if the trend observed deviates from what is expected.

URBAN WILDLIFE: CAN WE LIVE WITH THEM?

ABSTRACT: A survey of Extension Wildlife Specialists in the U.S. provided a basis for estimating the magnitude of urban wildlife damage and control in this country. Response to the 9-question mail questionnaire was good (76 percent) following the single mailing to all Extension Wildlife Specialists or people in similar positions listed in the national directory. The majority of questions were answered based upon the experiences and best estimates of these specialists for the interval October 1986-September 1987. Specialists had difficulty providing estimates of damage and costs of prevention and control; 57 percent were not able to provide any data on these topics. Several of the questions dealt with attitudes of people requesting urban wildlife information and/or assistance and wide ranges of responses were received to most of these questions. Most people (78 percent) appeared willing to implement prevention/control measures recommended by these specialists, more than half (61 percent) wanted the animal handled/removed by someone else, and only about 40 percent wanted the damage stopped regardless of cost. Also, slightly over half (55 percent) of clientele represented did not want the offending animal harmed in any way. These results were highly variable from state to state. Several differences were noted in overall responses regarding urban wildlife species. Requests for information were received most frequently for bats and snakes, but both of these groups of animals ranked very low in terms of actual damage reported. The most frequently mentioned groups of animals causing damage in urban areas were roosting birds (including pigeons, starlings, and sparrows), woodpeckers (especially flickers), tree squirrels, bats, and moles. In terms of actual dollar values of damage done, white-tailed deer and pocket gophers apparently caused the most estimated damage. Due to these differences, it is necessary to know which criteria are being used to make an assessment of the relative importance of animal damage control problems. Techniques for controlling urban wildlife damage, such as exclusion, live-trapping, repellents, and poisons, are compared and discussed in some detail in this paper. As urbanization occurs across the nation, concerns about urban wildlife damage will continue; in most cases, we can and will live among these creatures.

THE CURRENT STATUS OF PLAGUE IN CALIFORNIA

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 to permanent foci, and could result from epizootic migrations over considerable distances, and (4) a number of assumptions about areas of greatest epizootic potential can be made by analyzing the pattern of recurrent plague outbreaks in the past. Since then the validity of these assumptions has been tested by the largest outbreak of plague since the early 1940's. We believe that the results have proved the crystal ball largely correct, resulting in much more precise and efficient epizootic surveillance and deployment of control measures than in the past. The outbreak was for us an administrative emergency that exceeded the capacities of the State Health Department. We greatly appreciated the vital help and cooperation of other agencies and individuals. The U.S, Public Health Service accepted a heavy burden of laboratory testing through its San Francisco Field Station, and provided emergency field personnel. The contributions of State Department of Agriculture, Bureau of Weed and Vertebrate Pest Control; U.S. Parks, Forest Service and Bureau of Land Management; local health and agriculture department; and State Division of Parks personnel were essential in accomplishing control work, as well as epizootic surveillance.