Giant clams are the largest bivalve molluscs, possibly growing up to1.2m in length and weighing more than 227kg. Because of their huge size, they were rumoured to be man-eating clams in the 1920s -1940s. However, they are very docile animals and have a sessile adult phase.
Click here for a video that briefly dispels the myth! (This video is actually part of their original video on giant clams, so if you would like to get an overview of giant clams, you can watch this instead!)
To date, 13 species have been discovered and are categorised into two genera: Hippopus and Tridacna. They are usually found in the reef flats and shallow lagoons of the Indo-Pacific region.
Their lifespan is an average of 100 years and they are hermaphrodites i.e. possess both female and males’ sexual organs. 10 years are needed for them to reach maturity before they perform broadcast spawning to breed.
Another fact on the giant clams is that they are solar-powered animals. They have a symbiotic relationship with the algae, called zooxanthellae. Through the photosynthesis of zooxanthellae, it produces sugars and proteins to the giant clams while the giant clams’ mantles act as a home to zooxanthellae. No two giant clams have the same coloration which is produced by the zooxanthellae.