Public perceptions and knowledge of nationwide shellfish reef restoration

Large-scale restoration of coastal and marine ecosystems is increasingly used to address biodiversity loss, yet its long-term success depends on public awareness, understanding, and support. Despite rapid expansion in shellfish reef restoration worldwide, little is known about how the public perceive these ecosystems or the value of restoring them. We surveyed 867 coastal and metropolitan residents living within ~50 km of shellfish reef restorations across Australia to assess public knowledge, perceptions, and perceived benefits of shellfish restoration. Public knowledge of shellfish reefs was generally low: 92% of non-fishing respondents reported limited or no knowledge despite residing close to restoration sites. Knowledge was higher among recreational fishers — the key public stakeholder group for shellfish reef restoration — yet 60% still reported limited or no knowledge. Concern for coastal environmental health was high across all respondents, with 77% of non-fishers and 82% of fishers reporting moderate to high-level concern. However, perceived threats were largely skewed toward marine plastic pollution, with habitat and species loss not frequently recognised. Most respondents believed shellfish restoration could improve community well-being, yet human and socio-economic benefits of restoration were rarely reported relative to environmental outcomes. These findings suggest that while public support for marine restoration is strong, awareness of the broader societal benefits that justify restoration investments remain limited. Our findings highlight a critical knowledge gap that may constrain the social legitimacy and scaling of marine ecosystem restoration. Improving public awareness on both the ecological and societal benefits of restoration remain critical for building the long-term social legitimacy needed to scale marine ecosystem restoration.