Diversity of Tridacninae in Coral Reef Ecosystem on Gosong Island, Aceh Province, Indonesia

The aim of the current study was to determine the species diversity and the number and size of giant clams in the coral reef ecosystems of Gosong Island, Southwest Aceh. The survey was conducted in August 2024. Sampling was carried out using the line quadrat transect, consisting of two stations with a plot area of 50 x 50m2 at a depth of 4-10m. The study results presented three giant clam taxa: Tridacna derasa, Tridacna gigas, and Tridacna maxima. The largest size found at the study site was 120cm for the Tridacna gigas type. The substrates on Gosong Island, where the giant clams live, consist of six types: porites, alveolar, favorites, sand, dead coral algae (DCA), and macropore branching (ACB). A further finding is that the Tridacna derasa type was only found with a slight relative abundance of 0.0001 ind/m2 with a length of 55cm and was found on the DCA substrate. T. gigas was abundant on different substrates: porites, alveolar, favorites, sand, DCA, and ACB. The results of the study show that the genus Tridacna was found in low abundance on a variety of substrates. It is recommended that Tridacna clams in Gosong Island coral reef ecosystem, southwest Aceh, receive more management attention to conserve this rare giant clam.