Giant clams are also preyed upon by humans, who catch the giant clams in order to feed on a particular muscle which is seen as a culinary delicacy in many countries. The excessive harvesting of giant clams by humans has led to rapid declines in the world's giant clam population.
Giant clams have both male and female reproductive organs but are not thought to self-fertilise. Giant clams release eggs and sperm into the water, where the eggs will generally be fertilised by the sperm from another giant clam. Giant clams are able to release more than 500 million eggs at a time.