The coral reefs surrounding Pulau Durai (located in the northwest of Indonesia in the Anambas Islands, South China Sea) were surveyed from 22 June to 5 July 2011 to provide baseline data on their biotic composition and condition. At each of four sites around the island, point intercept methodology over two 50 m transects yielded an average benthic cover of 26% live hard coral. The maximum live hard coral cover observed was 47% on the northern side of the island where fishing boats anchor overnight to seek shelter from the southwest monsoon. The minimum of 3% live hard coral was observed on the west side, which is the inhabited area of the island and where there is the greatest amount of anthropogenic activity. A total of 38 hard coral genera and 115 fish species were recorded across all transects. The average biomass of fish per transect was 2135.5 kg/ha and the populations were mostly comprised of herbivores which correlated with the abundance of dead coral, algae overgrowth, and lack of predator fish. Crown-of-thorns starfish (Acanthaster planci) were present at all sites with a maximum of 15 individuals sighted on both the North Shallow and South Shallow transects.
In general, damage from anchors and destructive fishing practices have gravely impacted Pulau Durai‟s reefs in the past. Present threats include continued anchoring, over-fishing and a current infestation of crown-of-thorns starfish, which are negatively affecting the remaining health and abundance of living coral. Pulau Durai and its neighbouring island, Pulau Pahat, were declared a marine protected area in July 2011. Given the depleted state of this reef, it will be imperative to establish a “no-take” fishing area to restore the fish populations, ban anchoring on the reef to stop the destruction of coral, and if possible, remove the crown-of-thorns starfish.