The Giant Clam Sanctuary in Guinsiliban, Camiguin is located in a bay near Cantaan. In there lies a beautiful white sand beach named Kaliba Beach where a sanctuary of giant clams awaits the visitors. Kabila Giant Clam Conservation and Ocean Nursery homes more than 2,600 clams including the giant clams in which one can find the seven (out of nine) species of giant clams in the world.
Upon going to the sanctuary one can found a notice from the management which indicates that the Kabila Giant Clam Conservation and Ocean Nursery is a non-government project and all proceeds are used in the maintenance and conservation of giant clams as well as the marine sanctuary.
Visitors can roam around the Giant Clam Sanctuary facility and see the different sizes and colors of the clams. On the round pools, baby clams are placed for breeding purpose while the giant clams are placed in a giant pool in which they are expected to reproduce. The facility also houses clams that can create pearls.
[READ] Information about giant clams:
The giant clam, Tridacna gigas (known as pā’ua in Cook Islands Māori), is a clam that is the largest living bivalve mollusk. T. gigas is one of the most endangered clam species. Antonio Pigafetta documented these in his journal as early as 1521. One of a number of large clam species native to the shallow coral reefs of the South Pacific and Indian oceans, they can weigh more than 200 kilograms (440 lb), measure as much as 120 cm (47 in) across, and have an average lifespan in the wild of 100 years or more. They are also found off the shores of the Philippines, where they are called taklobo, and in the South China Sea in the coral reefs of Sabah (Malaysian Borneo). T. gigas lives in flat coral sand or broken coral and can be found at depth of as much as 20 m (66 ft). Its range covers the Indo-Pacific, but populations are diminishing quickly and the giant clam has become extinct in many areas where it was once common. T. maxima has the largest geographical distribution among giant clam species; it can be found in high- or low-islands, lagoons, or fringing reefs. Its rapid growth rate is likely due to its ability to cultivate algae in its body tissue.
Although larval clams are planktonic, they become sessile in adulthood. The creature’s mantle tissues act as a habitat for the symbiotic single-celled dinoflagellate algae (zooxanthellae) from which it gets nutrition. By day, the clam opens its shell and extends its mantle tissue so that the algae receive the sunlight they need to photosynthesize.
“Why are the giant clams becoming endangered?”
The main reason that giant clams are becoming endangered is likely to be intensive exploitation by bivalve fishing vessels. Mainly large adults are killed since they are the most profitable.
The giant clam is considered a delicacy in Japan (known as Himejako), France, South East Asia and many Pacific Islands. Some Asian foods include the meat from the muscles of clam. On the black market, giant clam shells are sold as decorative accoutrements. At times large amounts of money were paid for the adductor muscle, which Chinese people believed have aphrodisiac powers. A team of American and Italian researchers analyzed bivalves and found they were rich in amino acids that trigger increased levels of sex hormones. Their high zinc content aids the production of testosterone.
“The legend of killer clam or man-eating clam”
As is often the case with uncharacteristically large species, the giant clam has been historically misunderstood. It was known in times past as the killer clam or man-eating clam, and reputable scientific and technical manuals once claimed that the great mollusc had caused deaths; versions of the U.S. Navy Diving Manual even gave detailed instructions for releasing oneself from its grasp by severing the adductor muscles used to close its shell.
In an account of the discovery of the Pearl of Lao Tzu, Wilburn Cobb said he was told that a Dyak diver was drowned when the Tridacna closed its shell on his arm.
Today the giant clam is considered neither aggressive nor particularly dangerous. While it is certainly capable of gripping a person, the shell’s closing action is defensive, not aggressive and the shell valves close too slowly to pose a serious threat. Furthermore, many large individuals are unable to completely close their shells.