12th edition of Marine Life monthly post. I can’t believe that it’s been a year this monthly post existed. Thank you for keep following this monthly post! This monthly post aims to share information on specific marine life species and to promote their conservation.
Here is our video how a giant clam closes its shell. Dutchie took this movie in Raja Ampat, Indonesia.
I always find the giant clam as pretty animal because of its beautiful color patterns on its mantles. I was inspired to write about the clam after watching a sad short movie of a dying clam sucking salt on kitchen table to stay alive. Little I knew about the clam when I watched that movie. After reading some articles about the clams, I find five interesting facts about this animal that may surprises you. This time, I am focusing only on the giant clam (genus Tridacna)- the largest mollusks on earth.
1. Clam does not eat human or chew any part of human’s body
The giant clam is often being called as man-eating clam and considered dangerous animal. There is a myth of the giant clam as man-eater animal in South Pacific area. The fact is the giant clam does not eat human who were swimming near to it or accidentally step on it . I am sorry to disappoint you, the giant clam feeding sounds boring but certainly good news for human: its feeding mainly by filtering the nutrients from the water.
The giant clam closes its shells in action of defending itself. Based on our experience of seeing the giant clams closed their shells, they were unable to close their shells completely.
2. It lives up to 100 years
Yes, the giant clam can live that long and even longer! The clam usually stay in one place for the rest of its life. It is a bottom dwelling animal, it stays on the ground and growing bigger. The size of the giant clam could reach to 1.3 meters and weight to 250 kilogram.
3. It is a hermaphrodite
A giant clam has both male and female reproductive organs, it can produce offspring without another clam as partner. At first it reaches its maturity as a male, after a year, it becomes a hermaphrodite.
4. It can produce “pearls”
Have you heard Pearl of Allah or later being named as Pearl of Lao Tzu? The pearl was declared as the largest pearl ever found in the world and it produced by a giant clam in Palawan, the Philippines, in 1934. More story about this special clam’s pearl, please read: The Pearl of Allah: the Facts, the Fiction, and the Fraud. Pearls produced by the clams usually very rare but the clams have capability to produce the ‘pearls’ that categorized as “Calcareous Concretion”. Unlike the oysters’ pearls, the clams’ pearls usually not valuable due to its quality and irregular shapes.
Unfortunately some species of the giant clams (genus Tridacna) are listed by IUCN Red List as vulnerable species and its population close to be endangered. This happened because of excessive fishing exploitation. The giant clam’s adductor muscle is popular because it believed to have aphrodisiac powers. Its colorful mantles also popular for interior decoration. The giant clams farming is now developing in Micronesian countries. I am not sure how sustainable the nursery in practice but perhaps that could stop the reducing number of the wildlife giant clams.