Oysters Emilie Blotiau

Scientific Name Oysters scientific name is Crassostrea madrasensis

Physical Characteristics Have a rough outer shell. Inner shell is smooth from the erosion of sand.

Anatomy Oysters have gills like fish that filter the oxygen out of the water. They are filter feeders, and use beating cilia to catch food. They have a small three chambered heart that lies under the adductor muscle. The mantle contains many small blood vessels which filter for oxygen in the water.

Habitat Live mostly in the intertidal zone. Live between rocks and attached to hard substrates. No preference to ocean temperature however they feed best at 50 degrees. Reside mostly in brackish water.

Oysters Diet Oysters are filter feeders. Plankton and other particles are caught by the beating cilia, and get stuck in the mucus membrane of the gills. –The gills transport the food to the stomach.

Reproduction One cannot determine if an oyster is male or female by their shells. –they are one sex or the other (not hermaphroditic). –Can change sex once or more during their lifetime. –It is almost impossible to tell the age of an oyster.

Interesting Facts Some types of oysters can produce pearls inside their shells. They can grow to be about a foot long. Oysters have blood and veins, their blood is colorless. It is extremely hard to open a live oyster shell. You must use a knife.

Pictures

Find the oyster in the pictures!