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- subject = Biology
- title = The Giant Clam
- papers = Please put your paper here.
-
-
-
- The Giant Clam
-
-
- The giant clam is known as a reef dwelling
- mollusk. The domestication factor has
-
- become of large importance to the
- Indo-Pacific peoples. Mainly in the area of their diet.
-
- These huge clams
- are huge targets for fishermen and can be found easily. With the crystal
-
- water
- complection of the reef waters they live in makes them even easier to be spotted
- by
-
- the fishermen an by poachers. The people of this region eat every part
- of the flesh of the
-
- animal. They either dry, cook, or eat them raw.
-
- In
- Taiwan there has been a large illeagal industry of selling these huge clams.
- With
-
- a demand of somewhere around 100 tons of the meat a year that is
- worth around $7.50-
-
- $21.25 a kilogram at the dockside of Taiwan. It is
- being severely poached by foreigners
-
- and the population of the giant clam
- is decreasing. The reefs that they live on are also
-
- being severely damaged
- and destroyed in large amounts. The giant clam has been
-
- eliminated from
- the areas of Indonesia and the Phillippines. The species Tridacnid gigas
-
- and
- the Tridacnid derasa are the most heavily hunted species.
-
- Tridacnid gigas
- are the largest of the giant clams. They grow to around a meter in
-
- length
- and weigh around 300 kilograms. These particular clams are hermaphrodites
- which
-
- reach sexual maturity at around five years of age. They spray out
- large numbers of their
-
- eggs and sperm into the seawater which then meet
- to form a free floating larvae. A large
-
- Tridacnid gigas has the ability
- to release hundreds of millions of microscopic eggs in a
-
- single day, which
- makes it one of the most fertile marine invertebrates. However most of
-
- the
- free floating larvae do not survive during their one week planktonic period.
- The ones
-
- that survive settle on a patch of hard reef by means of a sticky
- byssal threads and orient
-
- their fleshy mantles towards the sun. They
- continue to grow their at a rate of around five
-
- to ten centimeters a year.
- But they are not safe from other reef predators until they are
-
- around
- 2.5 years old, which makes this large species hard to find. About 100 of the
-
-
- original eggs will eventually become a full grown clam, but that number
- is much lower in
-
- dense and exploited areas of a reef. Usually they will
- continue to grow in that spot for
-
- several decades. There is also never
- any paternal care and the clam will probably move
-
- anywhere but deeper in
- the sand.
-
- In the Asia Pacific area there are many groups of scientists
- artificially cultivating
-
- these large clams in an effort to learn more about
- this rare and extremely over hunted and
-
- captured creature.
-
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