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1 . India     India
India, despite its vast size, has only a few coral reefs off its mainland coast, mostly concentrated around the Gulf of Kutch to the northwest, and the Gulf of Mannar near Sri Lanka in the southeast. Reefs are highly developed in the more remote archipelagos of Lakshadweep and the Andaman and Nicobar islands. The distribution and status of any reefs outside these areas remains largely unknown.

The reefs and coral communities of the Gulf of Kutch are predominantly patchy structures built up on sandstone or other banks or around the small islands on the southern side of the gulf. They have adapted to extreme environmental conditions of high temperatures, fluctuating and high salinities, large tidal ranges and heavy sediment loads. As a result diversity is low, with only 37 hard coral species recorded and no branching species. Coral sand mining was a significant industry in the Gulf of Kutch in the early 1980s and may have added to already difficult conditions. Chronic oil pollution in the area may also be affecting the reefs. There is an oil pipeline right through the national park, parts of which were impacted by a major oil spill in 1999. Industrial pollution is a further concern, and the clearance of mangroves may have increased levels of sedimentation. The impacts of the 1998 coral bleaching were quite varied within this area, but on average were much lower than on reefs to the south, with about 30 percent mortality. Further down the coast there are some small, low diversity communities, but conditions here are quite harsh, with low salinities during the monsoon and high turbidity and wave action. Corals are also reported from the Gaveshani Bank some 100 kilometers off the coast from Mangalore.

The best developed mainland reef structures are located in the southeast, with fringing reefs occurring off Palk Bay, and on the coasts and islands of the Gulf of Mannar, including Adams Bridge, a string of reefs stretching across towards Sri Lanka. Diversity is high in this area, with 117 hard coral species recorded, as well as a number of ecosystems including seagrass and mangrove communities. Unfortunately reefs in this region were recorded as rapidly deteriorating as early as 1971, associated with high levels of siltation and the removal of coral rock combined with cyclone impacts. Coral rubble mining still occurs in the region, and mining of sand from the beaches is ongoing. Fisheries are thought to have a considerable impact, with some 47 fishing villages comprising a total of 50 000 people. Apart from overexploitation of general reef fish stocks there are concerns about other fisheries including sea-fans, sea cucumbers, spiny lobsters, seahorses and shells for mother-of-pearl. About 1 000 marine turtles are taken annually and dugongs are also hunted. The 1998 coral bleaching event appears to have severely impacted the reefs in the Gulf of Mannar, with 60-80 percent mortality.

A large proportion of the reefs in both the Gulf of Kutch and the Gulf of Mannar now fall within legally gazetted protected areas, but these suffer from both weak management and virtually no monitoring. There are concerns that the Gulf of Kutch Marine National Park will be rescinded to allow for industrial development.

The Lakshadweep Islands (Laccadives) are located about 300 kilometers west of the southernmost tip of India. They are true atolls and related reef structures, built up over a volcanic base, marking the northernmost and oldest trace of the Réunion hot spot which went on to form the entire Chagos-Laccadives Ridge. There are 12 coral atolls with about 36 islands (with a total land area of 32 square kilometers), about a third of which are inhabited, and also four major submerged reefs and five major submerged banks. Typically the atolls have shallow lagoons, averaging a depth of 3-5 meters, with islands mostly occurring on the eastern rims. The outer slopes of the atolls descend steeply and have prolific coral growth. The local population on these islands numbers some 51 000, and fishing is an important activity, although largely focussed on offshore (non-reef) stocks. There has been sand mining in some lagoons which is likely to have impacted areas of reef. Tourism is a small but growing activity: access requires a permit and tourist numbers are currently below 1 000 per year. The 1998 El Niño warming event caused dramatic coral bleaching, with significant subsequent coral mortality of 43-87 percent. This is probably slightly lower than that experienced further south in the Chagos-Laccadives chain.

The Andaman and Nicobar group consist of some 500 islands. Many are the high peaks of a submerged mountain range, a continuation of the Arakan mountains of Myanmar. The islands fall into two clear districts: Andaman to the north and Nicobar to the south, separated by the 160 kilometer wide Ten Degree Channel. There are fringing reefs along the coastlines of many of these islands. Their location is far closer to Indonesia and the Southeast Asian center of biodiversity than to India, and species diversity is higher than at any other reefs in India, with some 219 coral species recorded and around 571 species of reef fish. Although only 38 islands are inhabited, the population has been rising rapidly, largely through immigration, especially in the Andaman District. Close to these areas there may now be some human impacts on the reef communities, while sedimentation is expected to increase as further areas are opened up to logging. At the present time, however, many of the reefs are still largely free from human impacts, and pollution generally remains low. Despite access difficulties, tourist numbers are growing, and dive operators are now taking divers to the islands on “live-aboards”, usually departing from Thailand. The reefs were apparently very badly affected by the 1997-98 bleaching, with up to 80 percent mortality reported in some areas. Recent surveys have nonetheless shown an average of 56 percent live coral cover, suggesting a varied impact among the reefs. A detailed network of protected areas has been established in the islands. The majority of these are terrestrial but extend to the coastline, offering at least partial protection to adjacent reef communities.
Source: Spalding, M.D., C. Ravilious and E.P. Green , 2001 , World Atlas of Coral Reefs . Prepared at the UNEP World Conservation Monitoring Centre. University of California Press,Berkeley,USA.421p. (See Document)

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