Since 1991, the declining state of coral reef ecosystems has sparked concern by mangers, scientists, and government officials at several major scientific meetings. The growing support for the International Coral Reef Initiative by nations around the world confirms the seriousness of the problem and demonstrates their willingness to take action.
The abundant biological diversity of the coral reef ecosystem, not only includes coral and the commercially important species associated with the reef but also tens of thousands of other plant and animal species. Thus, the status and trends of this ecosystem are not easily evaluated. Historically, most coral reef surveys have been limited to discrete reefs or species or have been time limited.
The status and trends of complete coral reef ecosystems around entire islands or reef tracts (e.g., the entire Florida reef tract) have never been comprehensively evaluated because of the complexity, length of time, and cost of such endeavors. Because of this lack of a comprehensive understanding of the status and trends of coral reef ecosystems on large scales, this report takes a very broad look at general patterns in the status and trends of these ecosystems today, what would be the consequences of coral reef ecosystem degradation to human populations, and some of the major existing management and research programs. Preliminary recommendations for conserving these valuable resources are also suggested.
Coral reef ecosystems are under increasing pressure, and the threats are primarily from human interaction. In some cases, natural disturbances further compound the effects of anthropogenic stress. Of the approximate 600,000 km2 of coral reefs world-wide, it is estimated that about 10 percent have already been degraded beyond recovery and another 30 percent are likely to decline significantly within the next 20 years.
In addition, the total size and dispersion of all protected reefs combined, even if they were effectively managed, is currently inadequate to preserve the biodiversity and fishery production of reefs in any part of the world outside of eastern Australia. Unless effective integrated coastal zone management is implemented, more than two-thirds of the world's coral reefs may become seriously depleted of corals and associated biota within two generations.
Coral reef ecosystems at greatest risk are in South and Southeast Asia, East Africa, and the Caribbean. However, people have damaged or destroyed reefs in over 93 countries. Rapid population growth and migration to coastal areas where coral reef ecosystems occur exacerbate the problem.
The resulting coastal congestion leads to increasing competition for limited resources and to increased coastal pollution and problems related to coastal construction. Technology also allows humans to exploit the reef with mechanical dredges, hydraulic suction, dynamiting, and large-scale poisoning. More specifically, the major causes of coral reef ecosystem decline include:
- Overexploitation of reef resources; fish stocks have declined significantly in many reef areas, especially near centers of human population;
- Excessive domestic and agricultural pollution; and
- Poor land use practices that increase sedimentation.
Tourism can be an environmentally friendly way of generating income from coral reef ecosystems, but only when resort development and operation are carefully controlled. Unlimited collecting, sport fishing, and accidental damage by waders, swimmers and boat anchors can all degrade the reefs that earn tourist dollars. Allowing sewage and other wastes from tourist facilities to pollute reefs or siting resorts so that beach erosion increases, can be even more degrading to the health of the reef than the direct damage caused by visitors.
Information for accurately evaluating the condition of the world's reefs is critical for effective management. However, in many cases this knowledge is lacking. Many countries with coral reef ecosystems need training and capacity building to apply scientific management principles. Since most countries have not incorporated integrated coastal zone management, economic and environmental decision making has not been fully integrated to protect and sustainably use coral reef ecosystems.
Given these trends, degradation of coral reef ecosystems would have significant impact on world food sources, a long-term negative economic impact on fishery and tourist industries, and a devastating effect on millions of people around the world for whom coral reefs represent the primary source of livelihood.
We therefore suggest the following:
Integrated Coastal Zone Management
- Immediate governmental priority must be placed on the development and implementation of integrated coastal zone management strategies to effectively manage the coral reef ecosystems of the world. These strategies should address human activities in the coastal watershed and marine area and involve combinations of:
Public education, including education in the use of traditional forms of reef tenure and management and education on sustainable use practices;
Economic incentives and alternative income generation;
Global or regional legal instruments should be used in an efficient manner as well as strengthened for the conservation and sustainable use of coral reef ecosystems;
Well-managed marine protected areas;
Regulation and enforcement of reef resource exploitation;
Management of tourism and recreational activities, e.g., education programs, installation of mooring buoys;
Management of land-based activities and coastal development, e.g., using environmental impact assessments (EIA), wise siting of facilities; and
Coral reef ecosystem monitoring, mapping, database creation, and restoration.
Combining these management techniques is critical for success. If used alone, these techniques tend to be ineffective over the long-term. They must be strongly supported at scales ranging from the village to nation and often at the regional scale as well. They must be oriented toward long-term sustainability of reef resources and designed to be adaptive to different cultures/governments and changing situations without compromising effectiveness.
There are a number of examples from around the world of good, economically viable and environmentally sustainable uses of coral reefs -- these come from traditional and indigenous resource-use systems and from western coastal zone management and protected areas systems. These examples should be studied, adapted, and used around the world to further promote sustainable use and conservation of coral reefs in a manner that should enhance rather than hinder economic development.
- A world-wide system of marine protected areas should be established to encompass at least 20 percent of all reefs. This should include widely dispersed small reserves involving up to a few tens of square kilometers, and several strategically located large reserves at the scale of hundreds or thousands of square kilometers. Examples of the latter would include the existing Great Barrier Reef Marine Park, as well as proposed parks encompassing the Chagos Archipelago in the Indian Ocean and similar systems in the Pacific and Caribbean regions. Ideally, these protected areas should form part of wider coastal zone planning initiatives encompassing the reef systems of entire countries and integrating the needs of local peoples, commercial fisheries, tourism, terrestrial construction and agriculture needs and nature conservation.
- A concerted effort must be made to enhance the capacities of countries, particularly developing countries, responsible for coral reefs to design and implement informed, effective integrated management systems, and to conduct scientific research. This implies not only the transfer of information, but more importantly, the exchange of experiential learning among developing countries.
Improved Scientific Understanding of Coral Reef Ecosystems
- Efforts must be enhanced to survey the coral reefs of the world to provide information on their ecological and management status.
- Scientific management information is needed for:
Understanding the relationship of natural to anthropogenic impacts;
Conducting damage assessments;
Understanding coral recruitment and the maintenance and renewal of reefs;
Understanding water circulation patterns to determine the distribution of reefs and the fate of pollutants; and
Developing an improved scientific concept of what constitutes a healthy reef so it will be possible to gage changes on impacted ecosystems.
- So that the health of coral reef ecosystems can be monitored in a systematic manner, the Intergovernmental Oceanographic Commission (IOC) Global Coral Reef Monitoring Network should be established and maintained. This will provide valuable data to the larger Global Ocean Observing System. This information will not only help local authorities monitor the health of their coral reef ecosystems and improve management capabilities, but it will also provide a perspective on the condition of coral reef ecosystems and climate change world-wide.
In conclusion, the coral reef ecosystems of the world represent an important resource, both in terms of global biological diversity and with respect to the well-being of the people who live near and depend upon them. Many are at risk and need better management. The future actions of managers, scientists, national bodies, non-governmental organizations (NGOs), local communities and international programs will be critical in saving these natural treasures.
State of the Reefs * May 1995