New research has shown the enormous benefits of restoring lost oyster reefs in Hong Kong, bringing significant environmental benefits. The city was once home to thriving reefs, but have declined drastically due to overexploitation and pollution.

What is Happening?

Benefits of Oyster Reefs

Marine Thomas, Conservation Project Manager, for TNC in Hong Kong, says, “Globally, we have lost 85% of shellfish reefs, making it the most endangered marine habitat on earth. Most people associate oysters with food, but less well-known is that oysters create reef habitats that support coastal marine life. Only by restoring these lost habitats can we start to bring back  some of the associated environmental benefits.”  

You might also like: Biden Enlists Ranchers, Indigenous Communities to Conserve 30% of Land and Water

Restoring These Oyster Reefs

Dr. Bayden D. Russell, an Associate Director of SWIMS and Associate Professor in the Research Division of Ecology and Biodiversity, HKU, says, “A previous SWIMS study found that Hong Kong is home to approximately 6 000 marine species and 26% of all marine  species in China. This new research adds to that list, as we’ve identified a small crab previously not seen in Hong Kong. This  shows us just how under-studied these ecosystems are.” 

Dr Russell says, “We were excited to find high natural recruitment levels which suggests that oyster reef restoration is possible without  hatchery intervention. We think that this recruitment is because traditional oyster farming in the Pearl River Delta has maintained populations of native oysters in the system in spite of the loss of oyster reefs and these farms could potentially act as a source of larvae.”  

Ms Thomas says, “While we are excited by the biological feasibility of restoration, unfortunately the human aspect remains our biggest challenge to bring these habitats back at scale. Shellfish habitats are still severely under protected in Hong Kong, with very little public awareness of their ecological value. Wild harvesting is a huge problem – as soon as oysters or mussels are big enough to eat, someone will harvest them. We are working with the government on gaining more protection and recognition for these important ecosystems and hope to include them in the next Hong Kong Biodiversity Strategy and Action Plan (BSAP).”

Featured image by: Flickr