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.

Competition Between Novelty and Cocaine Conditioned Reward Is Sensitive to Drug Dose and Retention Interval

The conditioned rewarding effects of novelty compete with those of cocaine for control over choice behavior using a place conditioning task. The purpose of the present study was to use multiple doses of cocaine to determine the extent of this competition and to determine whether novelty’s impact on cocaine reward was maintained over an abstinence period. In Experiment 1, rats were conditioned with cocaine (7.5, 20, or 30 mg/kg ip) to prefer one side of an unbiased place conditioning apparatus relative to the other. In a subsequent phase, all rats received alternating daily confinements to the previously cocaine paired and unpaired sides of the apparatus. During this phase, half the rats had access to a novel object on their initially unpaired side; the remaining rats did not receive objects. The ability of novelty to compete with cocaine in a drug free and cocaine challenge test was sensitive to cocaine dose. In Experiment 2, a place preference was established with 10 mg/kg cocaine and testing occurred after 1, 14, or 28 day retention intervals. Findings indicate that choice behaviors mediated by cocaine conditioning are reduced with the passing of time. Taken together, competition between cocaine and novelty conditioned rewards are sensitive to drug dose and retention interval.

Eating And Exercising: Nebraska Adolescents' Attitudes and Behaviors

Prevention Center Papers are occasional publications of the Nebraska Prevention Center for Alcohol and Drug Abuse. Their purpose is to make available information that would not otherwise be easily accessible. This Prevention Center Paper should be considered a working document and does not reflect the official policy or position of the University of Nebraska-Lincoln, The U.S. Centers for Disease Control, the Nebraska Department of Education, or Health Education, Inc. Prevention Center Papers are produced for a limited readership to stimulate discussion and generate a flow of communication between the Prevention Center and those interested in the broad field of disease prevention and health promotion.

THE ORGANISATION OF RABBIT CONTROL (Oryctolagus cuniculus) IN WESTERN AUSTRALIA

ABSTRACT: Under Western Australian legislation, landholders have an obligation to control rabbits on their properties; local authorities the responsibility to supervise their work whilst the Agriculture Protection Board has a Statewide supervisory and co-ordination role. Prior to 1950 (when the Agriculture Protection Board was formed) the central role was in the hands of a Government department which, through lack of staff and money was unable to provide adequate supervision, and rabbits were in plague proportions. Since 1950, the Board has actively engaged in a vigorous policy aimed at tighter control and supervision. To enable this, the Board has entered into a voluntary scheme with local authorities whereby the role of local supervision of landholders is passed to staff employed by the Board, but jointly financed by the local authority and the Board. A contract poisoning service is also pro¬vided by the Agriculture Protection Board to any landholder who is unable or unwilling, to meet his obligations in this area. Both services are subsidised. Two of the major reasons for the poor level of control existing before 1950, have thereby been minimised. Soon after its formation, the Board set up a research section which has devoted nearly all of its activities to applied research on control of the State's many vertebrate pest problems. In the rabbit control area, poisoning has received most attention. The "One-Shot" method of poisoning was developed after years of research. Fumigation is at present being closely studied as is the economics of complete eradication from some areas of the State. Greatest needs in the applied rabbit research field at present are: (1) a selective poison, or poisoning regime, which will not harm stock, and (2) a more complete understanding of the economics of control and eradication. The serious rabbit problem which existed in 1950 has been reduced to very small proportions, by organisational development using local research findings. These organisational developments have been implemented by circumvention rather than confrontation.

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.

PUBLIC POLICY EDUCATION: AN IMPORTANT WILDLIFE MANAGEMENT OPPORTUNITY

Suburban wildlife management issues are generating heated debate between citizen organizations, elected public officials, and state wildlife management agencies. Decisions are being made by town and county officials which directly impact or supersede state authority for managing resident wildlife. As an example, I will focus this discussion on the white-tailed deer (Odocoileus virginianus), management controversy at Durand Eastman Park, in the greater Rochester metropolitan area, New York.