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What do you do with an old Fijian leper colony? Build a giant clam farm.

Growing a giant clam
 Summary Introduction
  • Giant calms are becoming increasingly rare.
  • Fijians are farming giant clams to repopulate their reefs.

Giant clams are increasingly rare on Fiji’s coral reefs. They are big, brightly colored, unable to run away… and tasty. Fijians hope that farming giant clams can help to repopulate reefs by transplanting them onto protected reefs. Once enough calms have been transplanted, they can naturally repopulate the surrounding area.

 Giant clam farms Coral Reef Formations

Fijians hope that the farm-raised clams will help repopulate their reefs naturally by raising clams in a protected environment until they are large enough to survive on their own. Farming giant clams is a slow process that takes several years:

Step 1
Millions of egg and sperm are collected from ‘brood’ clams. These mature clams weigh 200-300lb (90-140 kg).

Step 2
Young clams spend 2-4 years in a hatchery until they grow to 3 to 4 inches (8-10cm) long.

Step 3
These immature giant clams are transplanted onto a reef near the farm complex. They are placed in large steel cages to protect them from predators, like octopus, crabs and parrotfish. Giant clams spend 1-2 years in these cages before being moved one final time.

Step 4
It takes 3-10 years for giant clams to mature from larvae into a clam large enough to be safe on the reef. These large bivalves are transplanted one more time to their final reef home.

But, what is to stop people from poaching these giant clams once they are transplanted onto the reef? Luckily, giant clam farming mixes well with the Fijian concept of Tabu.

 Giant clams & tabu Coral Reef Formations

Tabu places protection on part of a reef. Fishing is prohibited in tabu areas. The tradition of tabu has been used to create a series of locally managed marine areas (LMMAs) which protect about 5% of Fiji’s reefs.

Marine organisms grow bigger and produce more young in areas that are protected from fishing. Fish spill from protected reefs into areas where fishing is allowed. These fish are typically larger and of better quality than fish from overfished reefs. Protected reefs also help repopulate the surrounding area.

Farm raised calms are safe from interference in these protected areas. Fijians hope to raise enough clams to naturally populate Fiji’s reefs and giant clams be a common source of food once again.

See "The marine protected area" for more information about tabu and LMMAs.

 Leper colony to clam farm

Makogai Island lies 30 miles from the main island of Fiji. This island was a leper colony from 1911 until 1969. The Fijian government declared the reefs around Makogai a marine reserve in 1986, and created a facility for farming giant clams, marine snails (Trochus sp.) and sponges. This facility continues to raise these marine organisms surrounded by the old buildings left over from the leper colony.

 References How do we know that?

Crawford, C. (1990, June). Giant Clam Mariculture Information Sheet No. 1. Center for Tropical and Subtropical Aquaculture. PDF retrieved 27 August 2008 from http://library.kcc.hawaii.edu/external/ctsa/publications/gcinfo1.pdf

McCarron, S. (2007, May 29). Village Ecology and Economy of Giant Clams in Fiji: Restoration of a Cultural Resource. Center for Applied Biodiversity Science (CABS). PDF retrieved 27 August 2008 from http://science.conservation.org/portal/server.pt/gateway/PTARGS_0_124186_105801_0_0_18/Giant_Clam_proposal.pdf

Tawaka, K. (2006, August 9). Makogai in transition - Former leper colony to house state of art research station. Fijian government. Retrieved 27 August 2008 from http://www.fiji.gov.fj/publish/page_7246.shtml

UNEP-WCMC. (2005). Fiji – Makogai Island. United Nations Environment Programme-World Conservation Monitoring Centre. Retrieved 27 August 2008 from http://www.unep-wcmc.org/wdpa/sitedetails.cfm?siteid=315525&level=nat

Wikipedia. (2008, June 22). Tapu (Polynesian culture). Wikipedia. Retrieved 12 September 2008 from http://en.wikipedia.org/wiki/Tapu_(Polynesian_culture)

WWF. (2006, January 11). Tabu waters: Protecting Fiji’s Great Sea Reef. World Wildlife Fund (WWF). Retrieved 27 August 2008 from http://www.panda.org/about_wwf/what_we_do/marine/news/stories/index.cfm?uNewsID=55580

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