Thursday, 26 February 2009

Thailand’s Andaman - World Heritage

Thailand’s Andaman region spans four degrees of latitude and two degrees of longitude. It boasts spectacular land and seascapes across Thailand’s southern provinces of Phuket, Krabi, Phang-nga, Trang, Satun and Ranong.

A new assessment of the biogeography of peninsular Thailand shows the Andaman coastline to be more diverse than ever before imagined. A myriad of ecological processes and diverse geology are concentrated into an area of about 500,000 square kilometres. This diversity is reflected in the vast range of natural habitats and ecosystems that form key elements of the complex fabric of the landscape and marine environment. These include the northern and southern mangroves and seasonal forests, central beaches and forests, karst caves, shallow reefs and sea grasses, as well as islands further offshore.

Scientists are only now beginning to understand how ancient geological and ecological processes have combined to produce the dazzling biodiversity to be found above and below the sea.

This remarkable variety places the region alongside some of the most diverse areas on the planet, and make it unique in places. Peninsular Thailand is one of only two geographic areas where equatorial habitats have links to northern tropical areas via a narrow land bridge. The other is the Darién Gap in the Isthmus of Panama, connecting Panama in Central America to Colombia in South America. In Thailand, the land bridge occurs entirely within a single country, making it unique.

In only a very few locations around the world is it possible to see coral reefs, mangroves, sea grass and rainforest covered islands so closely juxtaposed. In the Andaman bioregion, these features also cover a larger area than in the Sian Ka’an Biosphere in Mexico or the Coiba National Park in Panama. Like the Andaman coast, the Sundarban National Park in Bangladesh features extensive mangroves but it lacks islands by comparison.

Compared with karst rock formations in China, Vietnam and Sarawak, those in Thailand’s Andaman bioregion represent a different period of geological history. Only Vietnam’s Halong Bay and Phong-Nha-Ke Bang World Heritage Area are comparable in size and beauty with the drowned karst seascape of Phang-nga Bay, and the islands stretching to its southeast.

Active fault lines criss-cross the region exposing rock layers from various geological ages. Some of the oldest rocks on the planet are found here, dating to the Cambrian era roughly 500 million years ago. The first evidence of human life in Thailand comes from rock formations in Krabi that are 40,000 years old. Dinosaur fossils are found here too.

These recent findings have led to a new quest by a Thai project team spearheaded by scientists from the Centre for Biodiversity of Peninsular Thailand at Prince of Songkhla University; Kasetsart University; the University of Hong Kong; and the Thailand Department of National Parks, Wildlife and Plants Conservation. Their shared mission is to protect and preserve this rich natural heritage.


  • Coral reefs - globally significant diversity
    The Thai Andaman Bioregion is home to over 300 species of the world’s 800 species of reef-building corals. A quarter of the world’s fish species are to be found here in about 1,200 square kilometres of coral reefs that support about two-thirds of the diversity of Australia’s much larger Great Barrier Reef, which is 344,400 square kilometres in area.

  • Sea grass beds
    Shallow waters stretching from Phangnga Bay to Trang support concentrations of important sea grass and serve as feeding grounds for the highest numbers of dugongs anywhere in the world outside Australia. The sea grass beds are also vital nurseries for many reef species.

  • Offshore islands
    The Surin and Similan islands form an extension of Myanmar’s Mergui Archipelago. Here, southern and northern flowing ocean currents converge in the eastern Indian Ocean and feature large underwater granite boulders. These characterize world-class diving spots noted for their diversity of marine fish, corals and crustaceans. Further south, ocean currents that flow northwards up the Straits of Malacca from Indonesia and the South China Sea converge with currents from the Bay of Bengal and the Indian Ocean. In this unusual part of the world, Hin Daeng and the islands of Racha, Adang and Rawi boast even greater marine fauna diversity.
  • Caves and karsts
    At Phang-nga Bay between Phuket and Krabi province, towering karst pinnacles covered with scrub forest and plants march seawards from the north, forming caves and arches at sea-level and below. Macaques, serow and flying foxes are some of the distinctive fauna peculiar to this distinctive habitat. The area is immensely popular with sea canoeists. Above them, world-class rock faces offer avid climbers serious challenges and truly spectacular views.

  • Forests and swamps
    Nearly 300 species and subspecies of forest birds reach their southern or northern-most distributions around the Isthmus of Kra, an area eleven to thirteen degrees north of the equator where the Thailand peninsula is only 45 kilometres wide. This means the rainforests in the Andaman bioregion are exceptionally diverse in birdlife. The phenomenon dates from ancient times when sea levels alternately rose and fell, isolating the bird populations of Indochina to the north from those of the Philippines, Malaysia and Indonesia to the south in the evolutionary process.

    At the Thai-Malay border, almost 600 genera of flowering plants reach their southern or northern limits. This is evidence of a second prehistoric event that shaped the unique biota of Southeast Asia. In the south and the north, old-growth mangrove forests form wide swathes, harbouring the early life stages of a diverse range of marine creatures.

  • Coastal dunes — the world’s most important nesting sites for marine turtles
    At Khao Lak, Tai Mueang, and north Phuket, coastal dunes protect beach forests and sleepy lagoons, forming some of the most important nesting areas for Leatherback turtles and other sea turtles in the region. Other than the larger islands in the eastern Indian Ocean, Hat Thai Mueang in North Phuket is probably the last beach left for Leatherback turtles on the mainland.

  • Rest stops for migrating birds and whale sharks
    Tidal mud-flats in the Trang, Krabi and Kraburi River estuaries, along with coastal flats in Phang-nga Bay, are internationally important feeding areas for migratory wader birds. Raptors use the forest corridor leading down the peninsula for their annual migration. In October, over a dozen species of raptors can be seen flying south over Thaleban National Park. Whale sharks frequent the Andaman coastline from October to May. Researchers postulate that whale shark movements are responsive to plankton levels and currents from the Bay of Bengal, both of which increase at this time of year.

The natural wonders of this stretch of the Andaman coastline form treasures that do not belong exclusively to any one nation. Serendipitously, they are to be found in Thailand but form part of the whole world’s heritage — a heritage for all mankind to share and enjoy. Promoting this notion has been a central plank of the Andaman Bioregion Project.

Protecting and Preserving Thailand’s Andaman Coastline
Although parts of the Andaman coastline have been impacted by various developmental and environmental pressures, and by tourism-related activities, eighteen coastal and marine national parks covering 5,380 square kilometres already receive some level of official protection. A further four wetland areas are protected as RAMSAR sites. RAMSAR is an international agreement to conserve and wisely use wetlands of special significance in 158 countries. Thailand has been a signatory to the treaty since 1998 and has nominated ten sites totalling 370,600 hectares for inclusion. Two-thirds of these lie in the Andaman Bioregion.

The Andaman Bioregion Project – Key Approach
The traditional approach to managing Thailand’s Andaman Coastline has been to protect this treasured set of existing national parks. Individual parks might justify nomination as World Heritage Areas. According to marine biology expert Dr Thon Thamrongnawasawat, places such as Phang-nga Bay where karsts, mangroves, coral and sea grass beds meet, easily make the inclusion grade on the grounds of diversity alone. So too would locales further offshore such as the Surin Islands, where human impact is lower and more easily managed.

By comparison, the Andaman Bioregion proposal in its complete form is a visionary approach to managing regional diversity with a solid grounding in science. Dr James True, the plan’s main architect, says it draws lessons from managing the Great Barrier Reef ecosystem by incorporating existing protected areas as the core features, but including other areas as buffers and special management zones. There are also exclusion zones for areas that are heavily degraded and cannot be protected.

Thais have long considered their Andaman coastline a biological treasure. Now scientists are able to demonstrate why this is so, and in so doing they are supporting its nomination as Thailand’s sixth World Heritage Area — the kingdom’s first in the marine realm.