The island was evacuated with the outbreak of World War II and work on the deposit did not resume until 1944.

[5] By October 1945 over 100 men were employed on Cockatoo Island and work was underway laying a foundation for the processing plant, building a jetty and layout the township.

[9] The townsite established by BHP contained a school, movie theatre, and even a lockup prison.

[2] In 2020, Cockatoo Island Mining Pty Ltd whose directors reside in Australia, India, Hong Kong, and mainland China, was granted a lease for the island until 2032, after consideration by the Foreign Investment Review Board.

Concern was expressed by Senator Concetta Fierravanti-Wells among others that this lease was near the mainland Yampi Sound Training Area used by the Australian Defence Force.

Rainfall is not frequent, being distributed over 36.8 precipitation days (exceeding 1.0 mm (0.039 in)), and is strongly concentrated in the austral summer.