Biak the main island of Cenderawasih Bay, and nearby Supiori Island are the respective locations for the Biak and Supiori Nature Reserves. These parks are bird sanctuaries that include beautiful varieties of parrots and cockatoos. Siak is the center for the illegal trade of unique Irianese birds, as well as a bustling headquarters for both the tuna industry and offshore oil drilling operations. The main village is Jayapura.

The island was discovered in 1567 by the Spain Alvarez was the Dutch government centre of Irivan-Java in the 16th century. During WW II Japan troups claimbed the island first of all other islands of Indonesia. The Japans must leave the islands after long duration fights with Australian troups in 1945.
Since 1968 the northwestern part of the island is a nature reserve.