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Marine and coastal areas

The marine and coastal systems of the region support a complex interaction of distinct ecosystems, with an enormous biodiversity, and are among the most productive in the world. Several of the world's largest and most productive estuaries are found in the region, such as the Amazon and Plata Rivers on the Atlantic coast, and the Guayaquil and Fonseca on the Pacific. The coast of Belize has the second largest barrier reef in the world. The waters off Chile and Peru support one of the top five commercial fisheries and the world's fastest growing fishery is off the coast of Argentina and Uruguay (IDB 1995). The region's coastal zone is 64 000 km long and encompasses 16 million km² of maritime territory. For countries such as the island nations of the Caribbean, Panama and Costa Rica, this territory represents more than 50 per cent of the total area.

Marine fish catch (Click image to enlarge) Source: compiled by UNEP GRID Geneva from FAO 1997c

The marine fishery catch has been growing fast in South America but the 1997-98 El Niño is expected to produce a large decrease

The total marine catch in 1995 was about 21 million tonnes (see graph above), some 20 per cent of the world catch. Over the decade 1985-95, many South American countries doubled or tripled their marine catch, and Colombia increased its catch fivefold. During 1970-83 Peru's catch fell from 12 to 2 million tonnes due to El Niño events but had increased to nearly 9 million tonnes by 1995 (IDB 1995). A large decrease is expected as a result of the 1997-98 El Niño, the most severe event recorded to date (see box right). The effects of fisheries on marine biodiversity and resource sustainability are also of major concern, since more than 80 per cent of the commercially exploitable stocks in the southwestern Atlantic and 40 per cent in the southeastern Pacific are either fully fished, over-fished or depleted (FAO 1997c).

El Niño   The term El Niño was originally applied to a tepid current found along the coast of Peru and Ecuador every Christmas. The term is now used to describe the exceptionally warm and long-lived currents that occur every two to seven years, beginning in the summer and lasting for as long as 22 months. El Niño effects are propagated across the world's weather systems. In South America, they have caused catastrophic floods in southern Brazil and along the Pacific coasts of Ecuador, Peru and Chile; severe droughts in Brazil's northeastern region and the Altiplano areas of Peru and Bolivia; and dramatic falls in the Pacific coast fish catch. The 1997-98 El Niño resulted in economic losses that exceeded the combined international non-reimbursable, non-military, development assistance for the same period.

A wide range of fisheries activities (industrial, artisanal and recreational) coexist in the Caribbean sub-region. Overall landings from the main fisheries rose from around 177 000 tonnes in 1975 to a peak of 256 000 tonnes in 1985 before declining to around 136 000 tonnes in 1995. According to an FAO assessment, some 35 per cent of the region's stocks are overexploited (FAO 1997c). The sub-region also has the highest percentage discard, mostly as by-catch of shrimp trawling.

Mariculture is less important than in some other tropical regions but is growing in countries such as Ecuador where a significant shrimp mariculture industry has developed, mostly in converted mangrove areas. Latin America produced 21.6 per cent of the world's farmed shrimp in 1995. Aquaculture in Chile is growing at more than 30 per cent a year, compared with 9.5 per cent worldwide. Activities are concentrated in salmon farming, induced by favourable export markets, and are generating some US$450 million a year in export earnings. In 1997 salmon exports were more 145 000 tonnes (Ministerio de Economía 1997), and this trend is expected to continue (Instituto de Fomento Pesquero 1998).

Tourism accounts for about 12 per cent of GDP in the region, mainly in coastal areas. Some 100 million tourists visit the Caribbean annually, contributing about 43 per cent of the Caribbean's combined GNP and one-third of export earnings (WTTC 1993). By the year 2005, scuba diving tourism alone could generate revenues of approximately US$1 200 million in the Caribbean (WTO 1994). In addition to generating employment (10 million were employed in tourism in 1993), tourism investments lead to important land use changes in coastal areas. Many rural coastal areas are experiencing a gradual shift from dependence on local fisheries and agriculture towards the provision of tourism services and related activities (WTTC 1993).

The region's ports are the second leading destination for containerized US exports, and the Panama canal is a major focus of maritime trade. The total tonnage passing through the region's ports increased from 3.2 to 3.9 per cent of the world total during 1980-90, and a marked increase is expected as a result of trade liberalization and privatization of the region's ports (UNCTAD 1995). Expanding ports and maritime trade are often accompanied by intensified transportation corridors in coastal ocean areas, as is happening off Argentina, Brazil, Ecuador and Uruguay.

All these activities are bringing rapid and often drastic transformation to coastal and marine areas. Land conversion is causing degradation of coastal habitats, including mangroves, estuaries and coral reefs. Mangroves, for example, have been disappearing fast over the past 20 years, and as much as 65 per cent of Mexico's mangroves have already been lost (Suman 1994). Coastal water quality has been declining throughout the region, due to increasing discharges of untreated municipal waste.

The threat to coral reefs (Click image to enlarge) Source: WRI, ICLARM, WCMC and UNEP 1998

Many of the region's coral reefs are under threat; the Caribbean sub-region is the most affected, with 29 per cent of its reefs at high risk

The reefs of the Caribbean and adjacent waters constitute about 12 per cent of the world total, and are good indicators of the severe damage that has been inflicted on the environment. Today 29 per cent of the sub-region's reef areas (see map) are considered at high risk due to increased run-off and sedimentation caused by deforestation, nutrient contributions from sewage from hotels and shipping, coastal construction and mining (Bryant and others 1998). Declining coastal water quality, reef degradation and beach erosion are linked in a cycle which threatens public health, shore-front properties and tourism.

Poor and landless people have settled in flood-prone coastal areas in countries such as Brazil, Ecuador, Guyana and Honduras, increasing coastal pollution, over-harvesting, and conflicts over access to traditional fishing areas (IDB 1995).

The need for integrated coastal management in the Caribbean   Industries dealing with horticulture and aquaculture, oil, lumber, chemicals, textiles, vehicle repairs and ship building have all added large quantities of hazardous materials to rivers, estuaries, wetlands and coastal areas, and have had major impacts on the aquatic and marine environments (Davidson 1990). Agrochemical residues are also found in estuarine and coastal sediments as well as in coastal waters. Land reclamation for residential, industrial, agricultural and tourism purposes has caused the degradation of coastal and marine ecosystems of the sub-region. Limited infrastructure serving the tourism industry and coastal settlements has further contributed to pollution problems in coastal waters. In addition to locally-generated waste, the increasing popularity of the Caribbean as a destination for cruise ships and yachts has led to an increase in the volume of waste being discharged directly into the natural environment, because port reception facilities for ship-generated solid waste are generally inadequate. In densely developed coastal areas, the risk of sewage pollution of coastal waters is high because of the height of the groundwater table and the absorptive capacity of the soils. In countries such as Barbados, Jamaica and Haiti, the degradation of protective reef systems by sewage-induced eutrophication has contributed to coastal erosion and the destruction of beaches. Clearly, careful planning and management of all sectoral activities simultaneously will result in greater overall benefits than pursuing sectoral development plans independently of one another. Integrated coastal management approaches are required, combining all aspects of the human, physical and biological aspects of the coastal zone within a single management framework.

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