OzFish delivers major expansion of Port River shellfish reef

After successfully trialing their Robust Oyster Baskets (ROBs) in the Port’s inner harbour, with native oyster spat colonising the ROBs, OzFish SA has just deployed another 1200 ROBs. These ROBs were built over the last two years by volunteers and comprise wire frames filled with clean Pacific oyster shells that attract spat, spawned by native oysters in the River.

This major expansion was made possible by funding from the Commonwealth’s Urban Catchment and Waterways program, following a commitment by Mark Butler MP prior to the 2022 election.

ROBs were first deployed in the Port River in 2022 and follows trials by the Estuary Care Foundation (predecessor to Friends of Port River) to return native oysters Ostrea Angasi to the Port River and to trial small shellfish reefs made from coir bags filled with clean Pacific oyster shell.

Hopefully the 2025-26 spawning season has lasted until late February and baby native oysters, scallops and hammer oysters (Malleus albus) are taking up residency within the ROBs. The ROBs are already attracting the interest of fish and hopefully of blue swimmer crabs. Monitoring the ROBs can potentially provide information about species present in the Port River, following the Harmful Algal Bloom, and the possible colonisation by feral species.