Phang Nga Bay

• Category: Marine and Oceanic Biomes.
• Geographic Location: Asia.
• Summary: This ecoregion, which was damaged by the Indian Ocean tsunami in 2004, faces continuing threats from increasing tourism and development.

Phang Nga Bay is a 154-square-mile (400-square-kilometer) area of water that lies between the Malay peninsula of southern Thailand and the island of Phuket, and is part of the Andaman Sea. The bay is shallow in nature and contains 42 islets, together with intertidal forest areas, mangroves, and coral reefs. Historically, the Phang Nga area represented a means of subsistence for the comparatively few fishing communities located in the region. Recently, tourist development on Phuket Island in particular has placed considerable pressure on the bay, in which coral diving, water sports, economic development, and attendant pollution have become prominent.

In 2004, the Indian Ocean earthquake and tsunami, one of the deadliest natural disasters in recent history and the third-largest ever recorded on a seismograph, forced water into the bay and led to mud displacement and sediment deposits. More than 5,000 people were confirmed to have been killed in Thailand by this event, 259 of them in Phuket and more than 4,000 in the province of Phang Nga as a whole. Investigations have indicated that perhaps three previous tsunamis have affected the region in the preceding 3,000 years.

The climate of Phang Nga Bay is tropical marine, with characteristic high annual rainfall and year-round high temperatures. Rain is abundant in the southwest monsoon season from May to October. The average annual rainfall is 140 inches (356 centimeters). The temperature fluctuates between 73 degrees F (23 degrees C) and 90 degrees F (32 degrees C).

Diverse Species

In 2002, an extensive portion of the bay was designated as a Ramsar site known as Ao Phang Nga Bay National Park. This was an effort to protect vulnerable species, including the dugong (Dugong dugon), Malaysian plover (Charadrius peronii), and black finless porpoise (Neophocaena phocaenoides). More than 80 bird and fish species are represented in the park, with three amphibian, 26 reptile, and 17 mammal species living in the associated coastal area. Other animal species within the park include the pantropical spotted dolphin, Indonesian white dolphin, wild boar, smooth-coated otter, long-tailed macaque, and the Sunda pangolin.

Fish found in the bay include the moray eel, puffer fish, and a variety of fish that live among the coral. Other marine species include 14 species of shrimp, 15 species of crabs, and 16 species of rays and sharks, including squat-headed hammerhead shark (Sphyrna tudes) and freshwater stingray (Dasyatis bleekeri).

There are blue crabs, swimming crabs, mud-skippers, humpback shrimp, mud-lobsters, pomfrets, goliath grouper, butterfly fish, sole, anchovies, scad, and rock cod, as well as rainbow cuttlefish, soft cuttlefish, musk crab, mackerel, spinefoot, grouper, black sea cucumber, brain coral, staghorn coral and flowerlike, soft coral. The park also contains well-known karst formations, limestone caves, and a lengthy history of occupation dating back to 10,000 years before present, when the whole area was above sea level.

Human Impact

The damage inflicted by the tsunami on the coastal mangroves in Phang Nga and elsewhere affected many trees and plants that had been recently planted or replanted. The processes of economic development and globalization in Thailand had taken a severe toll on the environment before the tsunami, particularly in the case of mangrove forests. The total amount of mangrove forest had declined to a low of about 413,000 acres (167,000 hectares) in the mid-1990s, which represented only about 30 percent of the historical extent. Much of this was due to intensive farming of brackish-water shrimp.

Some of this loss had been reversed before the tsunami, when, by 2004, about 605,000 acres (245,000 hectares) of mangroves existed, much of which were located in the south of Thailand, particularly on and around the muddy river mouths similar to Phang Nga Bay.

Recuperation of the mangroves and other forest areas, which has received support and consciousness-raising around the nation, has taken place in conjunction with maintenance of the important fishing industry in the bay and, particularly, prawn fishing. Because of environmental degradation and overfishing by trawlers in the Gulf of Thailand, fishing in Phang Nga and elsewhere has been placed on a community basis, in which fishers are entrusted with responsibility for sustainability issues in their area of operation.

The majority of the population in the Phang Nga Bay area recognize the importance of biodiversity, not just for its own sake, but also because of the attraction it represents for tourists. The variety of natural resources available on land and in the water has contributed to the presence of a network of diverse villages specializing in different forms of resource use, although with some activities held in common. Inevitably, large-scale tourism development around the bay, including hotel construction and the creation of water-based leisure activities, is placing increased pressure on the environment as a whole—as well as rising efforts to ease such pressure.

Some high-profile projects in this regard have received popular support, but results have been mixed. Damage to the coral reefs in the bay and the declining sea-turtle numbers are easy to understand, and have resonance on emotional and spiritual levels. Nevertheless, official exclusion zones on dynamite and poison fishing in the bay are often ignored, and inadequate enforcement permits industrial fishing to take place unhindered. Global warming, too, is exerting a cost, as sea levels are rising, delivering more stress on the intertidal zone, pushing saltwater farther inland where vegetation is less salt-tolerant, and leading to greater erosion problems in the aftermath of storm events. Rises in temperatures are also creating stress on coral reefs as higher temperatures can cause coral bleaching. To address the threats posed by climate change, the Kingdom of Thailand adopted a new program in 2021 aimed at advancing climate change adaptations in relation to marine and coastal areas.

Bibliography

Choowong, Montri, Naomi Murakoshi, Ken-ichiro Hisada, Punya Charusiri, Thasinee Charoentitirat, and Vichai Chutakositkanon, et al. “2004 Indian Ocean Tsunami Inflow and Outflow at Phuket, Thailand.” Marine Geology 248, nos. 3–4 (2008).

"More Ancient Cave Paintings Found in Phang Nga Bay." Phuket News, 5 Nov. 2020, www.thephuketnews.com/more-ancient-cave-paintings-found-in-phang-nga-bay-77889.php. Accessed 30 Nov. 2024.

“The Royal Thai Government Launches with UNDP Support a New Climate Change Adaptation Project Financed by the Green Climate Fund.” United Nations, 30 Mar. 2021, thailand.un.org/en/164906-royal-thai-government-launches-undp-support-new-climate-change-adaptation-project-financed. Accessed 30 Nov. 2024.

Seenprachawong, Udomsak. “An Economic Valuation of Coastal Ecosystems in Phang Nga Bay, Thailand.” Thailand National Institute of Development Administration, 4 Feb. 2016, link.springer.com/chapter/10.1007/978-981-10-0141-3‗5. Accessed 30 Nov. 2024.