The ‘canary of the estuary’, the contribution of Sydney rock oyster aquaculture to understanding and protecting Australian estuarine health

Context The Sydney rock oyster (Saccostrea glomerata) is an iconic Australian native species of great commercial and ecological significance, that has been farmed in New South Wales for over 150 years. Aim To highlight the role of S. glomerata industry in safeguarding Australia’s estuaries. Method Literature review. Key results S. glomerata, more than any other species, has served to highlight emerging threats to estuaries, ranging from viral and bacterial contamination to chemical pollution, and climate change. Their use as biomonitors and in bioassays for pollutants (metals, PAHs, PFAS and pesticides) has been instrumental in identifying and quantifying potential threats. The oyster industry provides one of NSW’s largest and longest-running monitoring programs for estuarine environmental conditions. Currently, S. glomerata is at the forefront of remediation efforts, leading legislative change in environmental protection, and using ecoengineering, reef restoration and selective breeding programs to bolster oyster resilience. Conclusions Even though the community has long recognised the intrinsic link between oyster health and estuarine well-being and works with industry to advocate for estuarine ecosystem conservation and the species present, the contribution the industry makes is underestimated. Implications Amid debate over aquaculture expansion, greater consideration of the positives arising from culture activities is warranted.