Oysters As you come near the sea at Caiyuan Fishing Port, numerous oyster culture racks can be seen offshore. Every June to Mid-Autumn Festival, it is the prime time to enjoy the fun of shucking oysters while slurping the sweet taste of your hard labor. Caiyuan oysters are the largest and sweetest in this season. Apart from raw oysters, Penghu fishermen also offer BBQ oysters, so you also have the choice of savoring the exquisite flavors of charcoal barbequed oysters with special sauce.