Hikkaduwa National Park is one of the second marine national park in Sri Lanka located away 112km from Colombo. The national park consisting with a fringing coral reef of high degree of biodiversity. Hikkaduwa’s Coral Sanctuary, established in 1988. The national park located in the wet zone. In April–June and September–November respectively. Inter-monsoon season is a dry period which is considered the best season to visit the park.
Fallacious Montipora species prominent 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.
Sea grass and marine algae belonging to genera Halimeda and Caulerpa are common in the seabed depth ranging from 5–10 m Sea grasses provide habitat to Dugong and sea turtles. Some species of prawns feed on the sea grass. Eight species of ornamental fishes also inhabit the reef, along with many vertebrates and invertebrates including crabs, prawns, oysters, shrimps 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. Black tip 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.