Technological change in the UK herring industry took place rapidly after 1965, due in part to the active encouragement encouragement given to fishermen to switch from driftnetting to pelagic trawling and purse-seining. The adoption and diffusion of these modern methods of capture stimulated a major expansion of output, but this very success was undermined by the depletion of the fish-stocks on which the industry depended. In the case of the West of Scotland herring fisheries, which were especially important to UK fishermen, the decline in fish-stock biomass caused vessel catch-rates to fall after 1973. The failure of international fisheries management, which acted as a permissive factor in the intensification of fishing effort, also had important economic implications as it resulted in the dissipation of resource-rent. The Authors calculate that the maximum sustainable ‘rent’ which could have been generated from the West of Scotland herring fishery was approximately £14 millions per annum at 1976-equivalent prices.

The resource-rent effectively financed the overcapitalization of the fleet and the decline which followed, and it is the speed with which this occurred that most distinguishes the herring fishery from others where technological change has taken place. The article concludes by arguing that, although the UK public authorities (notably the Herring Industry Board) might reasonably be criticized for pursuing a development strategy which resulted in economic and biological over-fishing, the international regime of fisheries management which prevailed at the time gave them little choice but to adopt a pro-active approach to technical innovation.

This paper deals with conservation issues and threats faced by the inshore fishery of Lake Kariba, where human actions such as poaching and introduction of alien species are threatening the indigenous species. Lake Kariba is a Man-made Lake that was created in 1956–58 and has undergone a number of changes from a eutrophic stage in its early years to the present oligotrophic state. Tied up with this were changes in hydrology, the initial filling phase being marked with high fish-yields, then the booming of the pestiferous Salvinia molesta, until 1971 marked the end of evolutionary changes and the beginning of the decline in nutrient status of the Lake.

One of the two fisheries of Lake Kariba is described: the inshore fishery, which is the richer and more interesting in terms of diversity and conservation. This fishery is exploited by artisanal fishermen who use ‘primitive’ means. The fish species involved are vulnerable, as they take a long time to grow and have generally a low fecundity as compared with the ‘sardines’. The famous sport-fish Hydrocynus vittatus (Tigerfish) is, in particular, threatened by human activities.

Fishery regulations and management laws are implemented by LKFRI — a Zimbabwe Government institute under the Department of National Parks & Wildlife Management. Whereas the regulations appear sound and reasonable, economic hardships and human population growth in the hinterland have caused changes in the attitudes of people. Fishing is an easy source of revenue, but policing it has become costly and difficult.

Floodplain wetlands are of major importance in semi-arid Africa, providing agricultural, livestock, forestry, and fisheries, products as well as many other goods and services. Through a case-study of a floodplain wetland in northern Nigeria, it is demonstrated that the factors determining the characteristics of floodplain fishermen, defined in terms of how they fish, where they fish, and when they fish, are spatially and temporally very complex and may best be analysed within a simple systems framework.

Despite the important values and functions that floodplains provide, many have been degraded owing to the construction of dams within their catchments. Studies of the social and economic impact of these developments tend to have adopted an ‘ecosystem’ approach to analysis that conceals the socio-economic complexity of the floodplain. However, if proposals to manage the water resources of river basins effectively are to be successfully implemented, it will be essential to understand the complexity of socioeconomic relations of floodplain users and their interaction with the environment. In conclusion, there is a need for much more detailed socio-economic studies that explore the ways in which floodplain inhabitants use the system in space and time.

Fishery in the village irrigation-tanks has long played an important role as a source of food in the traditional villages in the Dry Zone comprising two-thirds of the area of Sri Lanka. Therefore, the villagers have traditionally developed various management practices which lead to sustainable utilization of fishery resources. This study is an attempt to explore such practices pertaining to fishery in the irrigation systems in the traditional villages and to investigate their relevance to designing appropriate resource-management systems leading to ecologically sustainable development. The study indicates that the traditional practices which contribute to the sustainable utilization of fishery resources are fourfold: (1) ecological, (2) technological, (3) institutional, and (4) cultural.

The ecological set-up of the irrigation system of any given traditional village has evolved in such a way that it could facilitate the survival of fishes during the dry season, which is the major threat to their continuous survival. Though all small tanks dry out during the dry season, small amounts of water remain in some big tanks. As all tanks in any given catchment area are interconnected, the fishes remaining in the big tanks can migrate to the small tanks at the beginning of the rainy season and so re-colonize them. While the buffalo wallow which is located at the lower end of the paddy tract acts as a drought refugium, the natural vegetation-cover associated with the irrigation system provides food, a favourable microclimate, and materials required for the construction of nests by those fishes that make them.

Crop damage and livestock predation were a serious problem in three Village Development Committees (VDCs) situated adjacent to the Southwestern Part of the Royal Bardia National Park. The seriousness of crop and livestock losses varied considerably with the distance from the Park's border and the specific location of farms. This was explained by the variations in the distribution of animal wildlife inside the Park, the presence of natural and Man-made barriers, the availability of forested areas outside the Park, and the agricultural cropping pattern. Adjacent to the section of the Park with the highest animal densities, crop losses varied from 47% for Lentil to 24% for Wheat. Farther away, the extent of crop losses was reduced. In the ‘Far’ zone situated 2–8 km from the Park, only 3% of the Paddy was reported lost.

Two wildlife species, Chital and Wild Boar, were responsible for roughly half of the total damage to crops by animals. Damage from a newly-introduced population of Rhinoceros unicornis was increasing, with Paddy (Rice) and Lentil the crops most affected by that species. The economic value of livestock loss to wild predators was estimated to be two percent of the value of total crop losses. The estimated value of grasses harvested by local villagers inside the Park, seen as ‘compensation’ for crop losses and denial of access to traditional resources, constituted only 10% of the total economic loss from crop losses and livestock predation.

A key characteristic of conservation in the United States is the dichotomy between two main philosophies. One of these is anthropocentric and utilitarian, advocating the wise use of Nature and natural resources, while the other is basically ecocentric, as it espouses principles of nonuse and preservation. This dualism has existed since the early days of the conservation movement, when the formerly uncontrolled use of a supposedly limitless natural environment finally gave way to a policy of resource management which was designed to conserve Nature and resource availability within the framework of human utilization. Generally opposed to this historically dominant paradigm were those who believed in preserving Nature for its own sake, and who have laboured over the years to modify and ameliorate the prevalent, central pattern.

After a period of relative unconcern, conservation underwent a resurgence as part of the environmental movement of the 1960s and 1970s. Environmental quality was the key concern, being highlighted by problems of pollution and degradation of the natural habitat. While providing the impetus for some broad environmental and conservation measures, this central focus directed primary attention to setting the problems. The traditional dominance of utilitarian resource management was maintained, relying on our managerial and scientific skills to address heightened environmental concerns. The era also spawned a number of other philosophies and themes. These have included a renewed sense of the ethics and spirituality of Nature, the emergence of ecology as a publicly-recognized-as-important field of science, ‘greener’ ecocentric movements, theories advocating more radical change, neo-Marxist theory on the relationship between Man and Nature, and various themes on limiting environmental growth and stress especially imposed by everincreasing human numbers.

The objective of interest-groups is to influence policy. Conflict is inevitable when two or more interest-groups are in competition for scarce resources. It then becomes the responsibility of the state to accommodate or resolve the conflict. However, an additional complexity occurs if the state agencies are themselves undergoing transformation, as has recently occurred in South Africa.

These issues are explored, using as a case-study the conflict that occurred between environmental interestgroups and a mining company over an application to dredge-mine the sand dunes that line the eastern shores of Lake St Lucia in Natal. The nature and objectives of these groups is discussed, and the role of the press in the controversy is analysed. The interests of black settlers who wish to return to their ancestral lands following the collapse of apartheid are shown to complicate further the dilemma that confronts state policymakers. The changing nature of the ‘decision environment’ in South Africa is addressed, and group theory is used to explain the relationship between state agencies and the mining, environmental, and black settler group, interests. Stages in the policy environment to match the modes of change over the period of political transformation in South Africa are identified by levels of conflict and ambiguity in a contingency model.

Several lines of evidence suggest that humans may be sensitive to the scale at which environmental problems occur, and that humans perceive to be more urgent those environmental problems that happen over relatively shorttime duration and at relatively local-spatial scales, compared with those that happen over greater spans of time and space. If this is true, then solutions to environmental problems should be planned accordingly: i.e. incentive-based strategies to promote some type of conservation may be more easily implemented, and most appropriately socially-based, for environmental problems that occur at the smaller societal scales. For those that occur at the larger societal scales, incentive-based strategies may be most appropriately economically-based, and are likely to be more difficult to implement, than the socially-based ones at the smaller societal scales.

This theory is explored in the context of municipal solid wastes. There is some support for the general arguments in that various types of economic incentives have been effective in reducing household wastes across the scale of cities, and some more socially-based incentives appear to be effective in small town/neighbourhood settings, though much work on these issues remains to be done.