William Scott
Port of Melbourne is set to undertake the world’s first trial to remediate dredge material grounds by restoring shellfish reefs in Port Phillip Bay, in partnership with The Nature Conservancy Australia (TNC).
Dredge material grounds are areas of seafloor set aside for placement of sand and mud which have been cleared from navigation channels.
TNC Seascapes Conservation Officer VIC, Andrew Bossie, said that this is an incredible initiative.
“We are restoring half a hectare of new shellfish reefs over dredge spoil, something that has never been attempted before,” Mr Bossie said.
The trial commenced on 4 February, using a mix of recycled shell from TNC’s Shuck Don’t Chuck project and local limestone rock to form a new reef base on the seafloor.
These reef bases will be seeded with 400,000 Australian Flat Oysters, which will continue to grow and attach to the reef base and each other. Over time, they will create a living reef, filtering water, and attracting a diversity of fish and aquatic life.
Shellfish reefs once dominated up to half of Port Phillip Bay’s seafloor. However, as a consequence of historical overfishing, compounded by catchment-to-coast runoff and other factors, they are now considered an ecologically collapsed ecosystem.
In response, Port of Melbourne has invested $890,000 to support TNC in restoring shellfish reefs in Port Phillip Bay’s diverse ecosystem.
“We are incredibly excited to continue our shellfish reef restoration work by leading a world first trial. If successful, this project could catalyse the restoration of end-of-life dredge material grounds in other parts of Australia and the world.”
