In 1980 Mr Sanae Wattanathorn the governor of Phuket surveyed the province to identify sites worthy of preservation. He considered both the tourist potential and the local villagers needs at all sites. One location visited was at Saku village on the North Western coast of Phuket island, centred upon an area of community grazing land, the adjoining beach and bay. This site appeared to be suitable for preservation so it was recommended to the Royal Forest Department as a possible site for the creation of a National Park. The Royal Forest Department came and undertook several surveys to assess the site's potential . They realised that although the forest in the area was not especially diverse and in some areas had been replaced by fruit tree plantations, they did discover two large healthy coral reefs in the bay. They also noted the overall natural state of the site the clean water and its historic importance as a sea turtle nesting beach. The Royal Forest Department produced and filed a report with the government for the inclusion of the site as a National Park. Had Nai Yang as the site became known, was officially opened by Royal decree on 13th July 1981. It became the 31st National Park of Thailand and covered the area of coastline and extended 5 kms out to sea.
In 1992 the Royal Forest Department changed the name of the park in commmemoration of the 60th birthday of Her Majesty, Queen Sirikit. The park name was changed to Sirinath Marine National Park. The boundary covers a total area of 90 sq. kms. of which 68 sq. kms. (76%) is marine and 22 sq. kms. (24%) is terrestrial.
Thereíre many white sand beaches with range of Casuarina and beach trees. Furthermore, thereís coral reef located around National Park office at Hat Nai Yang.
Sirinath National Park located in the coast of Andaman sea, thatís why it rains all year round. Thereís wet season from May to September and its time of northeast monsoon, which bring the cold wind into this area from November to April. It doesnít low down the temperature but the rain from Ao Thai cool down the area.
Forest: types can divided into 2 main groups as follow:
Beach forest: This forest type is characteristic of the more exposed beachfronts around the coast of Thailand and is dominated by Casurina pines. Due to the severe water stress occuring above the beach zone the tree density and total species diversity in beach forest is low when compared to other forest types. This forest type covers approximately 2 sq. kms. and has a moderately rich bird fauna. Birds species recorded include Magpie robin, Common myna, Spotted dove, Asian fairy bluebird, Blacknaped oriole, Greater racket-tailed drongo, and several Bulbul species, There are also many Marine cicades which can be heard calling in the trees, this insect only occurs in this forest type.
Beach forest provides good shade with good ventilation due to the low tree density and thus makes an excellent location for picnic trips, with many people visiting during the holidays. These trees also provide a windbreak thus reducing the impact of tropical storms inland probably saving a considerable quantity of fruit each year. The trees also help to stabilize beach deposits.
The principle tree species occuring within the beach forest is; Common Ironwood (Casuarina equisetifolia) other species include; Tulip tree (Thespesia populnea), Tropical almond (Terminalia catappa), White Barringtonia (Barringtonia asiatica), Cajeput tree (Melaleuca leucadendra), Alexandrian laurel (Calophyllum inophyllum), Screwpine (Pandanus odoratissima), Asoka tree (Saraca indica), Black Poum (Eugenia cumini), Dillenia indica and Convolvulus (Ipomoea sp.).
Mangrove forest : This forest type is an evergreen forest type. It is restricted to the area where freshwater and seawater mix and cannot survive in pure freshwater or pure seawater. This forest type occurs in sheltered locations such as the mouth of streams and rivers flowing into the sea and especially in estuaries. At Sirinath National Park mangrove covers a total area of approximately 1 sq. km. Although this area is small the mangrove forest which occurs here is the most natural and unspoilt mangrove forest occuring on the island. Mangrove forest provides a protected habitat for many species, birds recorded include; Collared kingfisher, Roseate tern, Sanderling, Terek sandpiper, Bar-tailed godwit, White-breasted waterhen, Slaty-breasted rail, White-bellied sea-eagle, Brahminy kite and Large-billed crow, also Monitor lizards, Snakes including Mangrove snake, Turtles, Shrimps, Shellfish, Crabs, Fish including Mudskippers, Mullet, Groupers, and Garfish etc. Mangrove forest preservation is important as mangroves trees with their extended root systems are important in preventing erosion of the mudflats, they also act as a global sink for carbon dioxide a major greenhouse gas.
Tree species recorded include; Red mangrove (Rhizophora mucronata), White mangrove (Avicennia officinalis), Olive mangrove (Avicennia marina), Black mangrove (Bruguiera gymnorrhiza), Rhizophora apiculata, Ceriops spp., Xylocarpus granatum, Xylocarpus moluccensis, Lumnitzera racemosa, Heritiera littoralis, Finlaysonia maritima and Derris trifoliata.
Marine Environment :
The marine environment of Sirinath is quite diverse and the coral reefs present in the bay are some of the most pristine found in Phuket province. The reefs are located about 700 to 1000m away from the shore near the park restaurant. The coral reefs are found in water between 4 to 7 m deep. Some of the marine species occuring include; Plate corals, Soft corals, Sea fans, Tree corals and Sea anemones.