Shellfish reefs are complex living structures, similar in function to tropical coral reefs, but are formed by dense clusters of living oysters or mussels.
In Australia, it is estimated that 99% of natural shellfish reefs are functionally extinct. In the past, shellfish reefs were lost due to over-harvesting, disease, land reclamation and sediments from run-off.
In New South Wales (NSW), wild oyster and mussel populations still exist in most bays and estuaries but at very low densities compared to the pre-European period.
The loss of natural shellfish reefs and the benefits (ecosystems services) they once provided continues to contribute to the decline in health of coastal waterways, reducing water quality and significantly impacting coastal and marine biodiversity.
Shellfish reef restoration (SRR) has been prioritised in the NSW Marine Estate Management Strategy in recognition of these ongoing impacts. SRR is a new and developing environmental rehabilitation practice in Australia to repair these lost ecosystems.
The NSW Shellfish Reef Restoration Project Planning and Implementation Guidelines provides information to support SRR works in NSW, with a specific focus on substrate-limited (‘unseeded’), intertidal Sydney rock oyster (Saccostrea glomerata) reef restoration activities.
The guidelines feature a case study of works done at Port Stephens, NSW during 2019-2020 to complete the first large-scale shellfish reef restoration project in NSW. The sites have been named ‘Bindayimaguba Ninang’ and ‘Garuwaguba Ninang’ (Pindimar’s Oysters and Karuah’s Oysters), reflecting the special connection of the Worimi people to sea country.
This case study provides a real-world example of the planning, consultation, licensing, and implementation considerations required to deliver large-scale intertidal Sydney rock oyster reef restoration project in NSW.
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