Mikurajima is famous for breeding grounds of dolphins. On the other hand, it is also a breeding ground for unique Seabird Streaked Shearwater. There are many cats on the island, people live in island cherish life with the cat. Recently, many cats breed and eat chicks of Streaked Shearwater. Protective groups are engaged in searching cats for contraception and owner for the purpose of protecting Streaked Shearwater and cats.