Pumicestone Passage Shellfish Reef Restoration

Recycling used oyster shells for reef restoration work can be slow and dirty work. Australia’s only fishing conservation charity, OzFish Unlimited, recently welcomed a new purpose-built shell washer to accelerate the recycling process for its dedicated volunteers at Pumicestone Passage. The washer will clean recycled shells within the Shell Recycling Centre at the Ningi Transfer Station before they are sterilised in the sun for up to 4 months. OzFish Pumicestone Chapter purchased the washer with the help of a grant from the Australian Government’s Communities Environment Program that supports community groups to address local environmental outcomes. OzFish Pumicestone Passage Chapter President Elle Veary said the shell washer would benefit shell recycling on multiple levels.

The project to restore the once magnificent shellfish beds of the Pumicestone Passage will be enhanced for the second time on Friday 6th December with more reef structures of recycled shell being installed off Kakadu Beach. Shellfish have been synonymous with indigenous culture and Moreton Bay for thousands of years, but shellfish communities are now functionally extinct in the Pumicestone Passage due to over-harvesting, disease and poor water quality. On 6 December 2019, the third infill stage of The Pumicestone Shellfish Habitat Restoration Project will further enhance marine biodiversity and fish stocks and ultimately improve water quality in the Moreton Bay Region.

Samples of oyster shells were obtained from two experimental subtidal oyster patch reefs deployed 9 months ago as part of the Pumicestone Shellfish Habitat Restoration Trial. Samples of 100 oyster shells were examined for evidence of natural spatfall from rock oysters and other bivalves (honeycomb oyster, glory scallop) and colonization by other invertebrates. Results confirmed that survival rates of naturally recruiting subtidal rock oyster spat on the larger 9 month old reefs continue to be high.

Results to date have been very encouraging, including a doubling of fish numbers in the first 6 months, and increased fish activity over patch reefs, crate reefs and BESE reef modules compared to non-restored areas. Additional trial patch reefs were installed with improved fence modules in December 2018 to examine if further improvements to the original designs enhance the outcomes.