FISHERIES RESEARCH INSTITUTE,MOA,TAIWAN

The Penghu Marine Biology Research Center, Fisheries Research Institute, Council of Agriculture, Executive Yuan (hereinafter referred to as Penghu Center) has conducted experiments for three years. It uses the bussus regeneration characteristics of the artificial-propagated juvenile shellfish, to confirm the key operation technique for restoration and release of giant clam. There are a total of 2 categories and 13 types of giant clam globally, while 2 categories and 7 types are recorded in Taiwan, including the Tridacna noae distinguished in 2014. The giant clam listed among the Seven Treasures of Buddhism can be taken as food and art with ornamental value. It has been widely used by mankind since the ancient times. In recent years, the number of wide species declines sharply due to the excessive catching globally. During 1983-1985, 9 species under 2 categories of giant clam were successively listed in Annex II of the Convention on International Trade in Endangered Species (CITES). Penghu County Government has banned catching of giant clam species since 2006, expecting to lower the threat of excessive catching for wild species. In view of this, Penghu Center was actively engaged in the artificial propagation research several years ago. It combined the larval culture method with appropriate culture media, light and temperature, so the giant clam may grow quickly without additional baits feeding, which could achieve extremely high survival rate. Since 2016, it selected 6-8cm artificial-propagated juvenile shellfish and cut off the old bussus before release based on the regeneration characteristics within 5-7 days. The selected juvenile shellfish was dispensed on the wild hard media directly. The survival rate of the shellfish achieved as high as 75% after 3 weeks. In this way, it didn’t only increase the release amount, but also prevent the interference of the artificial media on the marine environment. Such improved release technique could be widely applied in Taiwan and other countries in need of giant clam restoration. Currently Penghu Center is still working on the evaluation of the optimal giant clam size for release. This could help improve the restoration and release of giant clam. Moreover, it can surely increase the release efficiency and accelerate the restoration effectiveness of wide species.