Guernsey oysters are a type of locally bred and grown oysters in the area of the island of Guernsey. To preserve their high-quality, the oysters are raised exclusively from the seed of oysters defined by best-quality shell and meat. Guernsey oysters are Pacific oysters, scientifically known as Crassostrea gigas, which consist of meat with a plump texture and a sweet flavor contained within a deep-cupped shell.