An investigation of stocks of giant clams (family Tridacnidae) in Java and of their utilization and potential

Abstract

Abstract. A survey was carried out in Karimun Jawa, a group of islands off the north coast of Central Java, in order (1) to investigate the environmental effect of the collection of giant clam shells used for floor tile manufacture, (2) to investigate the distribution and abundance of living populations of Tridacna spp. and to determine whether the larger species of giant clams are still to be found in the area and (3) to determine the suitability of this area for reseeding of giant clam species for mariculture and/or fishery development. Results showed that the collection of T. gigas shells for the manufacture of floor tiles did not have the same damaging effect on the coral environment as reported elsewhere. They also showed that populations of T, crocea, T. maxima and T. squamosa were still thriving while T. gigas, H. hippopits and T. derusa were extremely rare if not actually extinct, one individual alone of T. derasa being found. The potential for reintroduction of these latter species and for the encouragement of mariculture or fishery development into these islands seems great and is strongly advocated.