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Algal bloom information

The state government has created a web page that answers a wide range of questions and provides a list of links to other relevant state government agencies leading the response.

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O'Sullivan Beach Shellfish Reef

Construction of Adelaide’s second metropolitan native shellfish reef about 500 metres off O'Sullivan Beach is now complete.

The five hectare project was a partnership between The Nature Conservancy Australia (TNC), the Australian Government, the SA Department for Environment and Water and City of Onkaparinga.

Shellfish reefs are part of SA’s natural heritage and were once common along our coastlines. Sadly, from the late 1800s to mid-1900s the reefs suffered from the impact of overfishing, dredging, water pollution and disease. Shellfish reef habitats are important to the marine environment, fish breeding, and water quality, but they can also provide recreational and economic opportunities.

How was the shellfish reef constructed?

TNC collected about 7 tonnes of recycled shells from oyster farmers on Eyre Peninsula – shells that would otherwise go to landfill.
The shells were cleaned and bagged then sent to the hatchery at West Beach where they were seeded with native baby oysters.
A barge placed limestone rock 500 metres off O’Sullivan Beach to create reef bases across 5 hectares. Finally as part of the construction process, the tonnes of recycled shells were spread over the reef bases and the oysters will now begin to grow and connect to each other and the reef base.
Oysters are like the kidneys of our oceans, with each one filtering 100 litres of water a day. This helps improve local water conditions which supports the return of other ecosystems like seagrass.

Why O'Sullivan Beach?

Glenelg was the first metro shellfish reef site, with O’Sullivan Beach chosen as the next site as it offered suitable environmental conditions with good opportunities for colonisation of marine species from the nearby rocky reefs. Its vicinity to the O’Sullivan Beach boat ramp and close proximity to the shore makes it a lot easier for recreational access. Site specific O'Sullivan Beach shellfish reef questions are answered in this FAQ document.(PDF, 2MB) Project funding outcomes are outlined in this acquittal report. (PDF, 2MB)

O’Sullivan Beach was one of 13 sites identified for reef restoration under the Australian Government’s $20 million investment in Reef Builder. A partnership between the Australian Government and TNC Australia, Reef Builder aims to bring shellfish reefs back from the brink of extinction and support the economic recovery of communities impacted by bushfires and COVID-19 restrictions.

To find out more information on shellfish reefs and their benefits visit www.natureaustralia.org.au/reefbuilder

Monitoring is now underway.