When you look at an oyster that has been opened, it seems to be formless. But it is really a complex creature with a mouth, gills, stomach, liver, intestine, and heart. There are more than a hundred species of oysters. They vary widely in size, shape, habits, and flavor. But generally, oysters produce many young. Some of them spawn five or six times during a season.
A female oyster may discharge almost half a billion eggs in a single season! Luckily, less than 1 percent hatch and reach maturity, otherwise, the oceans of the world would be choked with oysters.
A young oyster begins to swim a few hours after it hatches in front of the egg. It is quite different in appearance from a fully grown oyster. In shape, it resembles a small purse, with a circle of fine, vibrating hairs, or cilia, at its mouth end. These hairs fall off and the oyster grows in a year to about one inch across.
But before this, when the young oyster is only a few weeks old, it attaches itself to a rock or other submerged object. At the end of a month or two it is about the size of a one pence piece.
One of the greatest problems an oyster faces is simply to survive against all its enemies. Young swimming oysters are eaten by adult oysters and by fish. Even the larger oyster that has attached itself to something can be attacked by creatures called “drills”. They bore holes through the valves and extract the soft parts.
What are the five species of oysters?
1. Pacific Oysters.
2. Kumamoto Oysters.
3. Atlantic Oysters.
4. European Flat Oysters.
5. Olympia Oysters.