Estuaries are among South Africa’s most productive and valuable ecosystems. These unique environments, where rivers meet the sea, act as natural filters, nurseries for fish and other aquatic species, buffers against floods, and vital hubs of biodiversity. They also underpin livelihoods by supporting fisheries, tourism, recreational activities and climate regulation. Despite their importance, the latest findings from the National Biodiversity Assessment (NBA) 2025) paint a concerning picture: 99% of South Africa’s estuarine extent is threatened.
Understanding the Pressures
Estuaries face multiple, interacting pressures. Pollution from urban and agricultural runoff, unsustainable water abstraction, severe overexploitation of living resources, and habitat modification are primary drivers of decline. Invasive alien species further disrupt native biodiversity, while changes to river flows—often due to dams and other water infrastructure—affect estuarine health and resilience. These pressures combine to reduce the ecological condition of estuaries, threatening their ability to provide essential services.
Pic: Jeremy Shelton
Impacts on Ecosystem Services
Healthy estuaries perform critical functions that benefit both people and nature. They filter pollutants, maintain water quality, regulate flood events, act as nurseries for depleted fish stock, and provide habitat for a range of species, including fish, birds, and invertebrates. Blue Carbon habitats (saltmarshes, mangroves and seagrass) sequester carbon and assist in long-term climate protection. When estuaries are degraded, these services decline, increasing costs for human communities and reducing resilience against climate change impacts, such as rising sea levels and extreme weather events.
What the NBA 2025 Webinar Will Cover
The fifth webinar in the NBA 2025 series, “Estuaries on the Edge”, will explore the condition, threat status, and protection levels of South Africa’s estuaries. Experts will discuss which estuaries are most at risk, the drivers behind their decline, and what conservation and restoration interventions are showing promise. The session will also highlight gaps in the current protected area network and suggest priority areas for action.
Pic: Jeremy Shelton
Why This Matters
Protecting estuaries is not just an environmental concern—it is essential for carbon sequestration, supporting fisheries, and maintaining livelihoods in coastal communities. By understanding the threats and focusing conservation efforts on the most vulnerable estuaries, South Africa can safeguard these ecosystems as living infrastructure that supports both people and nature.
Pic: Jeremy Shelton
Join the fourth webinar
This session provides a critical opportunity for scientists, policymakers, and communities to engage with the latest evidence on estuarine health and discuss practical solutions. Protecting and restoring estuaries is an investment in biodiversity, resilience, and a sustainable future for South Africa.
Webinar details
Date: 8 May 2026
Time: 13:00–13:45
Join the webinar: here
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