Seaweed production as a social-ecological system along the southeast Pacific coast

Abstract Seaweed production is a globally expanding activity that supports coastal livelihoods, phycocolloid industries, food systems, and emerging blue bioeconomy opportunities. However, its social-ecological implications differ strongly among production models. Chile represents a distinctive case because, unlike aquaculture-dominated systems in Asia, most national production depends on the extraction of wild seaweed populations by artisanal fishers. This narrative review examines Chilean seaweed production along the southeast Pacific coast through the Social-Ecological Systems Framework, integrating peer-reviewed literature, official statistics, technical reports, and institutional information published between 1980 and 2026. We synthesize evidence across four main SES components: Resource System, Resource Units, Governance System, and Actors, and analyze how their interactions shape resilience, vulnerability, and sustainability outcomes. Chile is the main seaweed producer in the Americas and one of the world’s leading producers of wild-harvested seaweeds. In 2025, national production reached 426,543 metric tons, with approximately 85% derived from wild populations. Brown seaweeds, particularly species of the Lessonia nigrescens complex and L. trabeculata , dominate production in northern Chile, whereas red seaweeds, including Gracilaria chilensis , Sarcothalia crispata , Sarcopeltis skottsbergii , and Chondracanthus chamissoi , are more relevant in central-southern and southern regions. These spatial patterns reflect biogeographic gradients, environmental heterogeneity, harvesting histories, market demand, and governance arrangements. Chile’s governance system combines Territorial Use Rights for Fisheries, Open Access Areas, bans, quotas, management plans, and participatory seaweed roundtables. These instruments can promote stewardship and ecological recovery, but their effectiveness is mediated by enforcement capacity, labour dynamics, market fluctuations, and asymmetries within value chains. Our synthesis shows that Chilean seaweed production is shaped by feedbacks among climate variability, wild population dynamics, international demand, governance responses, and local livelihoods. Dependence on global commodity markets, particularly demand from China, can intensify extraction pressure while concentrating economic benefits among intermediaries, processors, and exporters. At the same time, artisanal fishers and women seaweed workers often bear disproportionate ecological and economic risks. Future sustainability will require strengthening adaptive governance, improving equity across value chains, diversifying production through native species aquaculture and value-added products, and developing integrated long-term monitoring that links ecological indicators, market dynamics, governance performance, and community wellbeing under climate change and uncertainty.