Revealing the Distribution Patterns of Giant Clams in Tebabinga Reef, Derawan Island Waters

Giant clams (Tridacnidae) are among the most iconic reef-dwelling creatures in tropical seas. Their massive shells and vibrant mantle colors make them a favorite sight for divers. However, behind their beauty lies a pressing concern: overexploitation and environmental changes are threatening their survival.

A species of krill that is at the tebabinga coral location

A recent study by Bimo Aji Nugroho, Ahmad Fauzi, and Alfi Suciyati from Universitas Borneo Tarakan aimed to answer a crucial question: What are the distribution patterns of giant clams in Tebabinga Reef, and which environmental factors influence them?

Three Species, Two Distribution Patterns

Using the belt transect method across seven observation stations, the researchers found three species of giant clams:

• Tridacna crocea

• Tridacna kerasa

• Tridacna squamosa

The results showed clear differences in distribution patterns:

• T. crocea exhibited a clustered distribution (Id = 1.01).

• T. kerasa (Id = 0.84) and T. squamosa (Id = 0.79) had a uniform distribution.

Habitat preference also played a role. T. kerasa was most frequently found on massive coral, rubble, and sand substrates.

A Supportive but Not Perfect Environment

Overall, habitat conditions in Tebabinga Reef still support giant clam populations. However, some abiotic parameters—particularly salinity and dissolved oxygen (DO)—were recorded below the recommended quality standards. These factors could affect the clams’ growth and reproduction in the long term.

Why This Study Matters

Giant clams are not only part of the reef’s beauty but also natural filters that help maintain water clarity and ecosystem health. Understanding their distribution and habitat conditions is essential for sustainable management, ensuring these species are protected from further exploitation.

Reference

Nugroho, B. A., A. Fauzi, and A. . Suciyati. “Distribution Pattern of Giant Clams (Tridacnidae) in Tebabinga Reef, Derawan Island Waters, East Kalimantan:”. Jurnal Moluska Indonesia, vol. 9, no. 1, Apr. 2025, pp. 18-24, doi:10.54115/jmi.v9i1.121.