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The Giant Clam
One Hundred Years Old: Giant Clams Face Extinction
A Gentle Giant Persecuted by Man
People are always interested in the largest of a species; the best fighter, who would win, the lion or the tiger? (lion), the most venomous or poisonous (the box jelly and the amanita fungus, more or less), the ugliest or the most beautiful (Mandleson and my budgie, Woody).
Yes, some of these absolutes are subjective, if that’s not an oxymoron, others, based on empirical evidence, and none writ in stone.
But when we get to the largest, there is no doubt where some creatures are concerned. The Blue Whale is known by one and all as the largest animal in the planet’s history, (not counting a couple of evolutionary freaks that might have been marginally larger or heavier). And virus - if they are actually alive at all - the tiniest.
Where the phylum Mollusca, the Molluscs, is concerned - which include most of the world’s shell “fish,” there is no argument over which is the largest and heaviest member, it is the protagonist of my article today: The Giant Clam, the Tridacna giga.
These are the statistics that back my claim. You average oyster, complete, and in his shell, won’t weigh more than a pound or two, wet. The record for the Giant Clam is something like 750 pounds! And 5-feet across!
The are quite a few members of the family called Giant Clams, and they start with modest entrants, like the attractive Fluted Giant Clam, at a mere 14 to 20 inches across, and about 20 to 40 pounds in weight, to the granddaddy of the species, the Tridacna giga, found in the Cook Islands, etc. which can live to 100 years of age, and may have had individuals weighing close to half a ton.
Giant Clams can move around as youngsters, but the soon become “sessile,” (unable to move), finding the spot where they will live and die among the coral reefs, or other suitable areas, and assuring an easy target for predatory mankind.
This peace loving giant begins a symbiotic relationship with certain algae which grow inside the shell and body, providing nutrition. In return, the clam provides a safe haven where the algae can flourish; the clam opens into the sunlight of the shallow water he prefers, while photosynthesis takes place for the plants.
A hermaphrodite (male and female in one) the clam doesn’t have to seek a mate, which would be impossible, and although an individual can produce sperm and eggs, he/she cannot fertilize himself, so the eggs/sperm are released into the warm currents to find another recipient; this obviates the danger of close breeding; bad for any species, as can be observed by the shoulder-less, jaw-less and mindless British “ruling” classes.
The poor Giant Clam has suffered from bad press for centuries as lurid tales of divers are broadcast, trapped between the mighty bi-valve, watching the bubbles of their last breath head up to the gleaming surface as distant for them as another galaxy.
The creature has been called “Man-Eater Clam,“ or “Killer Clam,“ It’s all nonsense, of course. The clam could close powerfully on a human arm or leg, but it moves so slowly, they would have to be suicides! No doubt a few divers have been put into some trouble by being trapped by the giants as they closed in pure self-defence at a size 14 diver‘s boot in their stomach, (and why was it there?), but it was probably a shark which administered the coup-de-grace, following the blood trail from where the diver scraped his limb pulling it put of the clam’s maw.
The sad truth is, as usual, it is the clam that is in grave danger from Man. Mussel fishermen dredge the giants up and sell them for a good price. They are a delicacy in Japan, home of the seafood marauders of the seven-seas. Their huge shells are eagerly sought by inane interior designers from Beverly Hills. Not to be outdone, the folk I love to hate, the Chinese, clamour for the poor brute’s abductor muscle, saying it makes a powerful aphrodisiac. Doesn’t that make you mad? There’s a billion, plus, of the little yellow chumps running around already…and they need aphrodisiacs? Kill a gorilla for its hand, an elephant or rhino for its horn, a tiger for its bollocks. I’d castrate the lot if I was King! Grrrr!