Oyster Reefs & BSAP
Hong Kong’s new Biodiversity Strategy and Action Plan (BSAP) 2035 sets an ambitious path for nature conservation—and TNC is ready to deliver.
85% of Shellfish Reefs are Lost Globally,
Hong Kong is No Exception.
Despite Hong Kong’s rich marine biodiversity – home to over 5,900 species, or more than one-quarter of all marine species recorded in mainland China – marine conservation efforts have lagged far behind those on land. Only about 6% of Hong Kong’s marine waters are protected, well below the global target of 30%. Many ecologically important habitats, including oyster reefs, remain outside of protected areas and face persistent threats, particularly in western waters.
Oyster reefs and other shellfish reefs deliver vital benefits to people and the planet, including providing habitat for marine life, supporting fish production, regulating water quality and protecting coastalines. Yet, over the past two centuries, more than 85% of the world’s shellfish ecosystems have been lost. Hong Kong is no exception. Historical dredging, reclamation, and urban development have decimated once-abundant oyster habitats across the territory. Today, any remaining oyster reefs are not officially recognised as ecologically important, are unprotected and therefore highly vulnerable to ongoing harvesting, degradation and reclamation projects, including the proposed Kau Yi Chau Artificial Islands, which do not take shellfish reefs into account when conducting the Environmental Impact Assessment.
Often overlooked, the humble oyster is the unsung hero of our seas.
Starting life as microscopic free-floating larvae, young oysters will settle on hard surfaces – preferably the shells of adult oysters – to complete their development. Over time, as more larvae settle and grow, the oysters build large, dense colonies on top of each other known as oyster reefs. Click the box below to learn about the important role of oyster reefs:
Filter Water
Oyster reefs provide a multitude of benefits to nature and people. Just one oyster can filter 200 litres of water a day, helping improve water quality in our oceans.
Promote Biodiversity
Oyster reefs provide habitat and nursery grounds for many native species that are otherwise lost from our shores.
Fish, crabs and other marine species find food, shelter and breeding grounds among the shells, with one study in Hong Kong finding six times more biodiversity on oyster reefs than on mudflats.
Increase Fish Stocks
Oysters, mussels and clams all suck in seawater, filtering out edible algae and nutrients and depositing what they can’t eat on the seafloor. This provides food for invertebrates, like worms and crabs, that then help feed fish.
Stabilize Shorelines
Oyster reefs can buffer strong waves and reduce erosion, which makes the coast more stable and supports the growth of seagrass beds.
Hong Kong’s Cultural Heritage
Hong Kong has a long history culturing and harvesting oysters (at least 700 years). Traditional methods of oyster cultivation (bottom cultivation) designated as Hong Kong’s Intangible Cultural Heritage.
Beyond savoring oysters, the harvesting of oysters for lime production, a practice that started over 1000 years ago. By the early 1900s, the Pearl River Delta was producing thousands of tons of lime annually, with significant contributions from Macau to Jiangmen. In Hong Kong, records show a substantial workforce and fleet dedicated to shell extraction, supporting regional economies such as salt production and construction.
TNC's Key Recommendation
In 2025, the public had a once-in-a-decade opportunity to advocate for stronger marine conservation policies and the health of Hong Kong waters. TNC has submitted formal recommendations to AFCD and encouraged the public to take part by submitting their views.
Hong Kong Biodiversity Strategy and Action Plan (BSAP) 2035
On 31 December 2025, the Hong Kong government officially released the Hong Kong Biodiversity Strategy and Action Plan (BSAP) 2035 —a sub national BSAP informed by both the KMGBF and China’s national BSAP. We are thrilled to see an ambitious vision for nature conservation in Hong Kong, with many of the recommendations TNC and our partners advocated for during the public consultation process now reflected in the final document. In line with the KMGBF’s “whole of society” principle, TNC and our partners are expected to play an even greater role in delivering conservation outcomes under this BSAP.
Hong Kong’s new BSAP 2035 sets an ambitious path for nature conservation—and TNC is ready to deliver. Our work will turn these goals into real, measurable outcomes:
Coastal Protection Park (CPP)
The establishment of the CPP as a new protected area has been reaffirmed as a priority project. Our community led, site based work over the past eight years aligns closely with the proposed CPP geographical area. Our collaborative approach will help shape the future management plan and demonstrate a model for inclusive, finance enabled protected areas.Oyster Reef Restoration
For the first time, oyster reefs are recognized in Hong Kong’s conservation policy as a priority habitat restoration programme. We hope to scale up reef restoration to revive marine ecosystems and strengthen coastal resilience.Nature-based Solutions (NbS)
NbS now appear as an overarching target, a priority action, and recurring theme throughout the BSAP. Over the past three years, TNC has played a leading role in mainstreaming NbS with our policy partner Civic Exchange. Through policy advocacy and our upcoming NbS Conference in June 2026, we’re embedding NbS into Hong Kong’s climate and development strategies.Conservation Finance
Funding is critical for success. TNC will leverage global expertise to develop innovative finance models that make conservation sustainable.
The BSAP also emphasizes collaboration across the Greater Bay Area and beyond. TNC is proud to work alongside partners and communities to help Hong Kong become a regional leader in conservation. Together, we can protect nature, fight climate change, and create a healthier future for all.
City of Shells: Our Forgotten Oyster Reefs
To learn more about oyster reefs and why they matter to Hong Kong, please watch this TNC featured documentary which explores the ecological, cultural, and historical significance of these lost ecosystems – and the opportunity to restore them.
Read More
Hong Kong Oyster Restoration
TNC restores oyster reefs in Hong Kong to improve water quality, increase local fish production, and educate the public about the importance of these marine habitats.
Scaling Up Community Conservation for Deep Bay
Protect sensitive biodiversity along the coast and formulate long-term policy recommendations for the proposed Coastal Protection Park
Recycling oyster shells from restaurants to benefit nature
Get to understand TNC “Save Our Shells” Initiative
