The United Nations Convention on the Law of the Sea, 1982 affirmed in its Preamble that, “ the problems of ocean space are closely interrelated and need to be considered as a whole.” Nearly 20 years have passed since that declaration, but the need is still felt. There is an even more urgent need for effective management of the use of coastal and ocean resources in order to prevent degradation of the ocean and to protect and conserve the ocean resources and biodiversity. Effective and strategic institutional and domestic management is required for the sustainable development of the marine resources, to ensure that the needs of future generations are met while satisfying the requirement of the present. From the 1980s, Integrated Management of the coastal zone has been considered as a key management approach to achieve sustainable development.
The shrimp farming industry in Nigeria is an important export-oriented economic activity that has a negative ecological impact on coastal zone resources. It has both positive and negative socio-economic impacts on the coastal society. The existing sectoral management approach of marine resources and ocean activities inNigeria is an impediment to the sustainable development of this industry and other resources affected by it. A comprehensive national policy framework and an integrated management mechanism are needed for the protection ofNigeria’s coastal and marine environment and the resolution of social and economic conflicts existing in the shrimp farming and coastal area.
The study focuses on shrimp farming inNigeria as an example of a coastal use that can have a harmful effect on the environment and on other uses. It puts forward the idea that shrimp farming in Nigeria developed rapidly as a result of external economic forces. There is a lack of capacity in the management of shrimp farming and as a result, shrimp farming and other coastal uses are managed in a fragmented manner that does not take into consideration the negative impacts and eventually gives birth to social conflicts. This study proposes the adoption of an Integrated Coastal and Ocean Management (Integrated Coastal and Ocean Management ) approach in order to respond to specific problems and to avoid future difficulties. It recommends the creation of an Integrated Coastal and Ocean Management Commission, Environmental Impact Assessment and the strategic zoning of coastal resource use areas etc
1.1 BACKGROUND TO THE STUDY For centuries, the coastline has been the most important human habitat, and, as a result, has been subject to a wide range of development pressures (Holland, 1998). Shrimp farming represents additional pressure on these areas, at least potentially. While shrimp farming per se does not necessarily have a significant adverse impact on the coastal environment, inappropriate practices and unplanned development have led to a number of problems. According to Chua (1992), the main environmental impacts associated with shrimp aquaculture, and ways in which specific impacts can be reduced or mitigated are being researched into in this study.
The actual or potential environmental impacts of shrimp farming fall into the following categories: • Destruction of natural habitat (through direct conversion);
• Abstraction/contamination and salinization of groundwater;
• Organic matter and nutrient pollution;
• Harvest of brood stock and wild post-larvae (PL);
• Introduction of exotic species;
• Abandonment; and
• Use of fish meal in feeds.
Measures have already been adopted widely by the industry; in others, the suggestions are based more on theory than on practical application. In either case, more research needs to be undertaken to document the effectiveness of the proposed mitigation measures in addressing the impacts. From the outset, however, it should be emphasized that many of the impacts from shrimp aquaculture are not unique to that industry. Rather, they are typical of agricultural practices in general, especially where land is in short supply. It should also be noted that shrimp farms suffer a great deal from pollution caused by other activities, including agriculture and industry. Indeed, while many other activities are relatively careless of their environment, experienced shrimp farmers realize that long-term benefits result from maintaining environmental quality. When establishing new farms, water quality is one of the most important factors to consider; sites where industry, agriculture, or other activities are polluting the water should be avoided (Fegan, 1996).
Extensive shrimp farming takes place in the intertidal zone, commonly in or adjacent to estuarine systems. Semi-intensive and intensive shrimp farming usually takes place in the upper intertidal or just behind/above the intertidal zone, often in adjacent wetlands. Some shrimp farming now takes place in inland areas. Most tropical estuarine systems are dominated by mangrove, an intertidal ecosystem of tree and shrub species specially adapted to saline habitats, that support a wide range of other organisms. Shrimp farms can be constructed away from mangrove areas altogether.