The Nature Conservancy (TNC) today announced an innovative marine restoration project to help the recovery of shellfish reef ecosystems in Port Phillip Bay, Victoria.
Evidence shows that kelp can help the natural recruitment of bivalves (e.g., oysters and mussels) enabling them to establish and survive at higher rates. Exploring the strength of this symbiotic relationship is at the core of TNC's Port Phillip Bay Multispecies Reef Restoration Project, the first ever multi-species restoration trial involving kelp and shellfish reefs in Victoria.
Through a rigorous science-backed approach, the project is piloting new marine restoration techniques to help accelerate ecosystem recovery for the benefit of both people and nature.
This 'multi-species' approach has been developed by TNC in partnership with conservation aquaculture enterprise SeaGen Aquaculture, to significantly increase the success of shellfish reef restoration and decrease the time it would usually take to achieve the long-term benefits of ecosystem recovery.
"Evidence demonstrates that kelp can help to increase the settlement of shellfish onto the reef base, particularly on the top side of the reef where, often, nuisance filamentous algae can grow. The kelp helps to keep the limestone rocks clean, and encourages shellfish to naturally settle," Scott Breschkin, Conservation Officer for TNC said.
"This work will see us, for the first time ever, add around 1 million juvenile Blue Mussels and a few thousand Golden Kelp plants onto the 2 hectares of shellfish reefs TNC and partners have already restored at Dromana," Mr Breschkin continued. "While we have previously seeded reefs with mature Blue Mussels, this is the first time we've tried seeding the reefs with juvenile mussels grown on recycled shell cultch and biodegradable potato starch, which allows us to do this at a much higher density which we hope will increase their abundance on the reefs," Mr. Breschkin said.
Over the past year, SeaGen have developed new hatchery production methods for a range of species that have shown an alarming decline in extent, including Golden Kelp (up to 90% loss in parts of Port Phillip Bay), Giant Kelp (which has suffered a dramatic loss of 99% in Victoria over the past 50 years), and Blue Mussels (95% loss in Victoria).
"Aquaculture can and should play a really important role in helping to recover native species and ecosystems. By using the same technologies that produce sustainable seafood, we can help scale the production of shellfish and kelp to support large-scale restoration projects" said Dr Chris Gillies, Director of SeaGen Aquaculture.
"TNC has a long history of restoring shellfish reefs in Port Phillip Bay and the restored reefs are now well established. Through generous funding from the Ross Trust, we are thrilled to trial these new methods to boost restoration impact and support the recovery of shellfish reefs," Mr Breschkin added.
