The value and opportunity of restoring Australia's lost rock oyster reefs

• Published in: Restoration ecology 2020-03, Vol.28 (2), p.304-314
• Main Authors: McAfee, Dominic, McLeod, Ian M., Boström‐Einarsson, Lisa, Gillies, Chris L.
• Format: Article
• Language: English
• Subjects: Adaptation; Aquaculture; Biodiversity; biodiversity conservation; Climate change; Coastal waters; Coasts; Ecological function; Ecosystem management; Ecosystem resilience; ecosystem restoration; Ecosystems; Encroachment; environmental management; Environmental restoration; Environmental stress; Habitat loss; Intertidal environment; Marine ecosystems; marine habitat; Marine molluscs; Oyster reefs; Oysters; Recovery; Reefs; Reference systems; Restoration; Rocks; Shellfish; Shore protection; Shoreline protection; Shorelines; temperate reef; Water quality
• ISSN: 1061-2971; 1526-100X
• DOI: 10.1111/rec.13125

Recognizing the historical loss of habitats and the value and opportunities for their recovery is essential for mobilizing habitat restoration as a solution for managing ecosystem function. Just 200 years ago, Sydney rock oysters (Saccostrea glomerata) formed extensive reef ecosystems along Australia's temperate east coast, but a century of intensive harvest and coastal change now confines S. glomerata to encrusting the hard‐intertidal surfaces of sheltered coastal waters. Despite the lack of natural reef recovery, there appears enormous potential for the restoration of intertidal S. glomerata ecosystems across Australia's east coast, with large anticipated benefits to water quality, shoreline protection, and coastal productivity. Yet, no subtidal reefs remain and the potential for subtidal restoration is a critical knowledge gap. Here, we synthesize historical, ecological, and aquaculture literature to describe a reference system for the traits of S. glomerata reefs to inform restoration targets, and outline the barriers to, and opportunities and methods for, their restoration. These reefs support extremely biodiverse and productive communities and can ameliorate the environmental stress experienced by associated communities. Rock oyster restoration, therefore, provides an ecosystem‐based strategy for assisting the adaptation of marine biodiversity to a changing climate and intensive human encroachment. Though an estimated 92% of S. glomerata ecosystems are lost, there remains great potential to restore these valuable and resilient ecosystems.