Nature of positive impacts
The fisheries sector usually makes a valuable contribution to economic development of coastal areas. The relative dispersion of coastal small-scale fisheries adds to maintaining economically viable rural communities and balancing the trend towards growing coastal urbanization. In history, fisheries have often been the basis for human settlements and coastal development in both the rural and urban environments. For example, Iceland was established as a fishing settlement and the United States owes a lot to the cod fisheries. In Africa, artisanal fisheries often generate the capital needed by fisher-farmers to invest in agriculture. In well-managed fisheries, high resource rents can be generated and used to finance investments within or outside the sector. The sight of fishing activities (e.g. ports, fishing boats, landing sites and fish markets) is attractive to many people and often has considerable aesthetic value to both those living permanently in the area and tourists.
In addition to its direct contribution, the indirect multiplier effects of the fisheries sector on economic development are often significant through intrasectoral interactions (e.g. between capture fisheries and ancillary activities such as net-making, or between capture fisheries and aquaculture through the supply of fishmeal), as well as intersectoral interactions (e.g. between forestry and fisheries through the supply of timber for boat-building, or between agriculture and aquaculture through the supply of feed). Fishing or fish farming is often undertaken next to other economic household activities including farming and small trade. These multiple economic occupations not only bridge the often-great seasonality in the abundance of fishery resources, but also insure against risks of failing production in any one of these activities. Moreover, these complementary pursuits may in some cases determine part of the fisheries sector dynamics; for example, the supply of capital and labour of the fishing activity may evolve in close relation to agricultural activities undertaken by the household.
The infrastructure developed for fisheries (feeder roads, landing sites and coastal havens, water-retaining ponds) tend to trigger further economic developments in other sectors such as tourism or agriculture.
An important contribution of the sector is the employment opportunities it generates, especially in remote and marginal areas. And not only in fishing but also in boat-building and maintenance, mechanical workshops for engines and gear, net-making and repair, handling, processing, packing and transport. In developing countries, it is estimated that some 39 million fishers (including those engaged in production, harvesting and landing site-based activities) are dependent for all or part of their livelihoods on fisheries. Together with their dependents, as many as 200 million people may rely on fisheries for their livelihood. The rapid development of aquaculture, for the local and export markets, and its rapid transformation in many areas into a commercial or semi-industrial activity is also contributing substantially to the development of rural areas.
The fisheries sector can also be an inexpensive "observer" and, potentially, "guardian" of the aquatic resources and environment of a country or a region, capable of alerting the relevant authorities in case of some major hazard such as pollution. Fishers and fish farmers often first witness major changes in ecosystems. Under this angle, and provided fisheries adopt a responsible attitude "across the board", as provided in the FAO Code of Conduct for Responsible Fisheries, fisheries could significantly increase their future contribution to sustainable development.
Some negative impacts result from the fact that fishing and aquaculture activities may affect the development of other economic activities. The presence of set fishing gear or aquaculture installations can be an impediment to navigation and tourism (through "hard" occupation of space and aesthetic damage to landscape) and the development of these activities competing for space need to be carefully integrated. Other negative impacts may derive from irresponsible fish production practices. Damage to fish habitats caused by some destructive fishing practices (e.g. dynamite) are deterrents to tourism. The destruction of coastal wetlands and mangrove areas by aquaculture pond construction and water pollution by intensive coastal aquaculture can have the same sort of effect. The presence of set fishing gear or aquaculture installations can be an impediment to navigation and tourism (through "hard" occupation of space and aesthetic damage to landscape) and the development of these activities competing for space need to be carefully integrated.
Negative impacts such as overcapitalization and overfishing may also result from heavy subsidisation in the absence of effective fisheries management.