A systematic review of interconnections between coastal intertidal molluscs, sustainable livelihoods, and the blue economy in South African coastal communities

Globally, intertidal molluscs are integral to the subsistence, commercial, and cultural identities of coastal and inland communities dependent on marine resources for survival. Despite their importance, the knowledge of intertidal zones in South Africa remains fragmented across ecological, socio-economic, and biotechnological disciplines. The research aimed to explore the potential of intertidal molluscs for socioeconomic development and as a livelihood alternative for poor coastal communities. To explore the potential of intertidal zones, a systematic literature review was done on work published between the years 2000 and 2025 following the PRISMA 2020 guidelines. Of the 142 studies screened from Scopus, Web of Science and Pubmed databases, 41 entries met the inclusion criteria. The findings indicate that key intertidal mollusc groups include mussels, oysters, abalone, limpets, and periwinkles. Intertidal molluscs make substantial contributions to coastal food security, small-scale fisheries production, aquaculture employment, and, consequently, household incomes in coastal communities. Abalone aquaculture dominates the human use while mussels and oysters support the livelihoods of economically disadvantaged coastal communities through both farming and subsistence harvesting. South African intertidal molluscs exhibit strong blue/bioeconomic potential through bioactive compounds, collagen, and shell-derived biomaterials; however, commercialisation remains limited. Sustainability challenges include overharvesting, pollution, climate change impacts, data gaps, weak enforcement, governance shortcomings, inequitable access to coastal resources, and the insufficient integration of local communities into mollusc-based value chains. This review identifies significant opportunities to expand a sustainable mollusc-based bioeconomy while strengthening livelihoods and enhancing community participation. It also highlights the underexplored potential of intertidal molluscs to support food security and socioeconomic development in South Africa. Further research is recommended on the food safety of molluscs harvested from rural coastal areas, and sustainable harvesting strategies.