Andaman Sea
At its southeastern reaches, the Andaman Sea narrows to form the Straits of Malacca, which separate the Malay Peninsula from the island of Sumatra.
Running in a rough north-south line on the seabed of the Andaman Sea is the boundary between two tectonic plates, the Burma plate and the Sunda Plate. These plates are believed to have formerly been part of the larger Eurasian Plate, but were formed when transform fault activity intensified as the Indian Plate began its substantive collision with the Eurasian continent. As a result, a back-arc basin center was created, which began to form the marginal basin which would become the Andaman Sea, the current stages of which commenced approximately 3â€"4 million years ago (Ma).
Other important sources of nutrients in the Andaman Sea are seagrass and the mud bottoms of lagoons and coastal areas. They also create a habitat or temporal shelter for many burrowing and benthic organisms. Many aquatic species migrate from and to seagrass either daily or at certain stages of their life cycle. The human activities which damage seagrass beds include waste water discharge from coastal industry, shrimp farms and other forms of coastal development, as well as trawling and the use of push nets and dragnets. The 2004 tsunami affected 3.5% of seagrass areas along the Andaman Sea via siltation and sand sedimentation and 1.5% suffered total habitat loss.
The sea waters along the Malay Peninsula favor molluscan growth, and there are about 280 edible fish species belonging to 75 families. Of those, 232 species are found in mangroves and 149 species (51 families) reside in seagrass; so 101 species are common to both habitats. The sea also hosts many vulnerable fauna species, including dugong (Dugong dugon), several dolphin species, such as Irrawaddy Dolphin (Orcaella brevirostris) and four species of sea turtles: critically endangered leatherback turtle (Dermochelys coriacea) and hawksbill turtle (Eletmochelys imbricata) and threatened green turtle (Chelonia mydas) and Olive Ridley turtle (Lepidochelys olivacea). There are only about 150 dugongs in the Andaman Sea, scattered between Ranong and Satun provinces. These species are rather sensitive to the degradation of seagrass meadows.
The sea has been used for fishing and transportation of goods between the coastal countries. Thailand alone has produced about 943,000 tonnes in 2005 and about 710,000 tonnes in 2000. Of those 710,000 tonnes, 490,000 account for trawling, 184,000 for purse seine (415 vessels) and about 30,000 for gillnets. The production numbers are significantly smaller for Malaysia and are comparable, or higher, for Burma. Competition for fish resulted in numerous conflicts between Burma and Thailand. In 1998 and 1999, they resulted in fatalities on both sides and nearly escalated into a military conflict between these countries. In both cases, Thai navy intervened when Burmese vessels tried to intercept Thai fishing boats in the contested sea areas, and Thai fighter aircraft were thought to be deployed by the National Security Council. Thai fishing boats were also frequently confronted by the Malaysian navy to the extent that Thai government had to caution its own fishermen against fishing without license, in foreign waters.
The 2004 marine production in Thailand was divided as follows: pelagic fish 33%, demersal fish 18%, cephalopod 7.5%, crustaceans 4.5%, trash fish 30% and others 7%. Trash fish refers to non-edible species, edible species of low commercial value and juveniles, which are released to the sea. Pelagic fishes were distributed between anchovies, Indo-Pacific mackerel (Rastrelliger brachysoma, 18%), sardinellas (Sardinellars spp., 14%), scad (11%), longtail tuna (Thunnus tonggol, 9%), eastern little tuna (Euthynnus affinis, 6%), trevallies (6%), bigeye scad (5%), Indian mackerel (Rastrelliger kanagurta, 4%), king mackerel (Scomberomorus cavalla, 3%), torpedo scad (Megalaspis cordyla, 2%), wolf herrings (1%) and others (2%). Demersal fish production was dominated by purple-spotted bigeye (Priacanthus tayenus), threadfin bream (Nemipterus hexodon), brushtooth lizardfish (Saurida undosquamis), slender lizardfish (Saurida elongata) and Jinga shrimp (Metapenaeus affinis). Most species are overfished since 1970sâ€"1990s, except for Spanish mackerel (Scomberomorus commersoni), carangidae and torpedo scad (Meggalaspis spp.). The overal overfishing rate was 333% for pelagic and 245% for demersal species in 1991. Cephalopods are divided into squid, cuttlefish and molluscs, where squid and cuttlefish in Thai waters consists of 10 families, 17 genera and over 30 species. The main mollusk species captured in the Andaman Sea are scallop, blood cockle (Anadara granosa) and short-necked clam. Their collection requires bottom dredge gears, which damage the sea floor and the gears themselves and are becoming unpopular. So, the mollusk production has decreased from 27,374 tonnes in 1999 to 318 tonnes in 2004. While crustaceans composed only 4.5% of the total marine products in 2004 by volume, they accounted for 21% of the total value. They were dominated by banana prawn, tiger prawn, king prawn, school prawn, bay lobster (Thenus orientalis), mantis shrimp, swimming crabs and mud crabs. The total catch in 2004 was 51,607 tonnes for squid and cuttlefish and 36,071 tonnes for crustaceans.
The sea’s mineral resources include tin deposits off the coasts of Malaysia and Thailand. Major ports are Dawei, Mawlamyine, Mergui, Pathein and Yangon in Burma; George Town and Penang in Malaysia; and Belawan in Indonesia.
The Andaman Sea, particularly the western coast of Malay Peninsula, is rich in coral reefs and offshore islands with spectacular topography, such as Phuket, Phi Phi Islands, Ko Tapu and islands of Krabi Province. Despite having been devastated by the 2004 Sumatra earthquake and tsunami, they remain popular tourist destinations. The nearby coast also has numerous marine national parks â€" 16 only in Thailand, and four of them are candidates for inclusion into UNESCO World Heritage Sites.
Related Sites for Andaman Sea
- Andaman - Andaman Island - Andaman Sea - All About Andaman … read Andaman Sea
- Andaman Sea (sea, Asia) -- Encyclopedia Britannica read Andaman Sea
- Luxury Beach Resorts Langkawi: The Andaman, a Luxury … read Andaman Sea
- Phuket Thailand Hotels: the Andaman Seaview Hotel in Karon … read Andaman Sea
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