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Hikkaduwa National Park is one of the two marine national parks in Sri Lanka. The
national park contains a fringing coral reef of high degree of biodiversity. The
area was declared a wildlife sanctuary on May 18, 1979, and then on August 14, 1988,
upgraded to a nature reserve with extended land area. The growth of the number of
visitors in the next 25 years increased the degradation of the coral reef. To reduce
the effects to the ecosystem, the reef was declared a national park on September
19, 2002. Coral reef
Hikkaduwa coral reef is a typical shallow fringing reef with an average depth of
around 5 metres (16 ft). The coral reef reduces the coastal erosion and forms a
natural breakwater. The coast of the national park extends four km. Generally the
coast is narrow, ranging from 5-50 m according to the climatic conditions of the
year. Scuba diving is a popular recreation here.
Physical features
The national park situated in the wet zone and receives a 2,000 millimetres (79
in) of annual rainfall. The rain is received in both southewestern and northeastern
monsoon seasons, in April-June and September-November respectively. Inter-monsoon
season is a dry period which is considered the best season to visit the park. The
temperature of the water ranges from 28.0°-30.0°C while the mean annual temperature
is 27°C of the atmosphere.
Flora and fauna
Foliaceous Montipora species dominate the coral reef. Encrusting and branching species
are also present. Faviidae and Poritidae corals are contained in the inshore areas
of the reef in massive colonies. Staghorn, elkhorn, cabbage, brain, table and star
corals are all present in the reef. Corals of 60 species belonging to 31 genera
are recorded from the reef. The reef also recorded over 170 species of reef fish
belonging to 76 genera.
Seagrass and marine algae belonging to genera Halimeda and Caulerpa are common in
the seabed depth ranging from 5-10 m. Seagrasses provide habitat to Dugong and sea
turtles. Some species of prawns feed on the seagrass. Eight species of ornamental
fishes also inhabit the reef, along with many vertebrates and invertebrates including
crabs, prawns, shrimps, oysters and sea worms. Porites desilveri is an endemic coral
species of Sri Lanka. Chlorurus rhakoura and Pomacentrus proteus are two reef fish
species confined to Sri Lanka. Blacktip reef shark are found along the outer slope
of the reef. Three sea turtles which have been categorized threatened visit the
coral reef: the hawksbill turtle, green turtle, and Olive Ridley.
The reef has suffered high degradation due to both natural and human activities.
The live coral cover was decreased from 47 percent to 13 percent in a coral bleaching
event in 1998, induced by the 1998 El Niño. It has been suggested that at least
30-40 percent of coral reef should be restored in order for it to be capable of
sustaining itself. Despite being designated as a protected area, the coral reef
has been subject to constant exploitation including removal of breeding ornamental
fish for the commercial market.
Boxing day tsunami
The two marine national parks of Sri Lanka, Hikkaduwa and Pigeon Island, received
little direct impact from the Boxing day tsunami. However they suffered from secondary
impacts, particularly from terrestrial debris being deposited on the reefs. A collaboration
work of conservation groups and volunteers was carried out to clean up the beach
and the reef debris, including two large fishing nets stuck on the outer edge of
the reef.
Coral types of Hikkaduwa
Staghorn coral
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Elkhorn coral
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Brain coral
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Table coral
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