Diversity of coral reef and reef fish in Isau Island, Central Maluku, Indonesia

Coral reef ecosystems are one of the ecosystems found in tropical waters and have an important role in people's lives. Damage that occurs to this type of ecosystem can affect the abundance and diversity of reef fish, which are part of its associated biota. One of the regions with high coral reef ecosystem potential in Indonesia is Maluku Province. One of the islands in Maluku Province, a diving tourism destination with corals and varied reef fish, is Isau Island. Therefore, research on the diversity of coral reefs and reef fish in the waters of Isau Island must be done to determine the condition of the coral reef ecosystem. Hard coral cover is 73.43%, determined from observations using the line intercept transect method at three stations in the waters of Isau Island. In this ecosystem, 108 species of coral and 255 species of reef fish were identified. The condition of coral reefs in the waters of Isau Island was in a good category, with a hard coral cover of more than 70%. In addition, the diversity of coral fish on this island was influenced by the large number of hard corals with branching growth forms, which provide sufficient space for coral fish.