Invertebrates

Since technical constraints regarding the spawning of mature giant clams and raising of larvae and juveniles were overcome in the 1980s, interest in giant clam culture and population management has increased considerably84. Giant clam mariculture has several advantages: the animals require no artificial feeding, rearing techniques are relatively simple and the setting up of facilities requires little capital investment and can involve local community members. Furthermore, unlike many other forms of mariculture it does not require broodstock to be continuously captured from the wild and hence the impact on wild stocks is minimal.

James Cook University in Australia, the Micronesian Mariculture Demonstration Centre (MMDC) in Palau and the Coastal Aquaculture Centre (CAC) in the Solomon Islands80 have developed pioneering research activities on clam mariculture. In the 1980s, scientists from Australia, the Philippines and a range of Pacific Islands nations (e.g. Kiribati, Fiji, the Solomon Islands and Palau) teamed up to further develop advanced giant clam mariculture technologies220.

The initial interest in culturing giant clams came from concerns related to the decline, and in some cases extinction, of wild stocks throughout their range, due partly to increasing pressure on coastal systems as a result of settlement expansion, pollution and improved harvesting efficiency. Hatcheries were initially developed to reseed depleted reefs and with the aim of growing clams as a food source to relieve pressure on wild populations81, provide employment and earn foreign exchange80. Nowadays, giant clams are also reared specifically for sale as aquarium species with government and commercial hatcheries in most tropical Pacific nations and island groups where giant clams are known to occur. These hatcheries are having commercial success because the giant clams can be sold at smaller sizes and thus the loss rate experienced due to predation on cultured stocks is reduced80. In fact giant clam farms developed for subsistence purposes showed poor economic viability82. Any conservation efforts for invertebrates other than clams and cleaner shrimps would be constrained by the near uniform lack of information on key life history characteristics.

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