Derbal Nara, known as Cockburn Sound, is a large, sheltered bay on the bordering lands of the Whadjuk and Pindjarup language groups on Noongar land and sea Country south of Fremantle.

It is a site of deep and continuing Noongar cultural connection with a significant marine ecosystem supporting seagrass meadows, penguins, snapper, sea lions and dolphins and much more. It is also one of the most heavily used stretches of coast in Western Australia with fishing, boating, diving and swimming, and is one of the state’s most industrialised waterways, hosting major ports, naval facilities and heavy industry.

The Sound’s ecosystems are already in a badly weakened state after decades of industrial pollution. Now four huge developments — a new container port (Westport), an expanded bulk-cargo jetty, the $25 billion Henderson Defence Precinct, and an $8 billion upgrade to the HMAS Stirling naval base to host nuclear-powered submarines — are all planned in and around the Sound at the same time.

This report explains what that could mean for the Sound’s wildlife and habitats, and why scientists are concerned about the combined, “cumulative” effect of the scale and timing of these projects.

Read or download the Summary Report.