01 December 2022
Rebuilding oyster-reef shorelines for hazard risk reduction and habitat restoration
When we think of oysters, we don’t usually think of the word ‘reef’ immediately after. However, oyster reefs represent crucial components of our ecosystems, serving as habitats for hundreds of species. In addition to promoting biodiversity, oyster reefs establish the first line of defence against erosion and flooding—issues that are too often addressed with unsustainable man-made solutions. Today, only 1–8% of oyster reefs remain across Australia, with many having been lost to overharvesting, habitat degradation, and poor water quality.
Countries worldwide are investing in rebuilding these oyster reefs, with ‘living shoreline’ projects now restoring oyster reefs to stabilise eroding coastlines. Australia is contributing to this effort, with a 2020 federal investment of a $20 million shellfish ‘Reef Builder’ program, unlocking the opportunity for oyster reef restoration projects nationally.
Dr Rebecca Morris is conducting research into how rebuilding oyster reefs impacts coastal erosion and promotes biodiversity. Rebecca has previously shown that how you design these oyster reefs determines the outcomes that you get for shoreline stabilization and oyster habitation through projects in the United States and locally on the Victorian coastline.
Future implementation of oyster reefs as an adaptation strategy to coastal hazard risk reduction in Australia can be informed through an understanding of the efficacy of oyster reef restoration projects currently designed to provide a coastal defense co-benefit. Rebecca would like to investigate whether patterns she observed in US oyster reefs will translate to native Australian oyster reefs.
“So many of us flock to the beach when we need a boost of energy; the cool sea breeze seems to have an instant effect on lifting our moods. We love the beach, but we are also the cause of so much damage,” said Dr Morris.
Rebecca’s research will help inform how the design of an oyster reef impacts on the delivery of coastal defense and local habitat, in the context of Australian oyster species. This will help in reconstructing the most effective oyster reefs that will allow us to conserve coastal ecosystems under close threat of repercussions from climate change.