The Pacific oyster, also known as the Japanese oyster, giant oyster, or giant Pacific Oyster, originates from Japan. The oyster is known for its distinctive white shell with purple blotches on the inside. A commonly farmed shellfish, the oyster grows to a length of 12 inches (about 30 cm) and can live for up to two decades.
Known by the scientific name crassostrea gigas, the oyster often makes its home on hard surfaces and also can be located in firm mud, sand, or gravel in depths of about 13 feet (about 4 m). An adult Pacific oyster best survives in temperatures between 39 - 75 degrees Fahrenheit (about 4 - 24 Celsius). While adults are adaptable and can live in a variety of environments, the oyster typically is incapable of reproducing in water temperature below 64 degrees Fahrenheit (about 18 Celsius).
The Pacific oyster is a fertile creature and spawns in July and August. The creature reaches sexual maturity by its first year. Generally, the female oyster releases 50 - 100 million eggs during spawning. Females discharge eggs that appear as white clouds and males release its sperm. For oysters to reproduce, fertilization must take place within 10 - 15 hours after spawning.
During breeding season, the oyster's reproductive organs may make up half of its body. The oyster changes sex during its life, typically forming as a male and then later changing to a female. The environment plays a vital role in determining the creature's sex. When food is plentiful, males are inclined to turn into females. Conversely, when food is in short supply, females tend to change into males.
The creatures are filter feeders. Oysters consume tiny biological matter, such as bacteria and plankton, helping to keep the ocean clean. Predators of the Pacific oyster include the starfish and crab, particularly in the Pacific Northwest and British Columbia.
Pacific oysters are indigenous to northeastern Asia. The creatures have also been introduced to other parts of the world, including Europe and North America. In the United States, the oysters are generally farmed in Washington and Oregon. The creatures were brought to the Pacific Northwest in the 1920s when the oyster population was dwindling due to overconsumption. Farmed oysters are raised using suspended systems such as ropes or trays from the ocean floor.
A popular delicacy, Pacific oysters have a mild flavor and a creamy texture. Varieties of the oyster include Fanny Bays, Golden Mantle, Hama Hamas, Mad River, and Penn Cove. A popular way to enjoy the oyster is by preparing it as a bisque.