The world is your oyster. Quite the common saying. But in HK the reverse is also true: oysters are the world. These saltwater bivalve mollusks hold a significant place in Hong Kong's cultural and economic landscape. China, the world's largest oyster producer, accounts for 80% of global production, while Hong Kong oysters represent about one-third of this output. The market value of these oysters ranges between 1.5 to 1.8 billion USD, underscoring their economic importance. For over 700 years, oysters have been a vital commodity in Hong Kong, contributing not only to the local economy but also to its rich cultural heritage.
Despite their historical significance, the oyster industry in Hong Kong faces numerous challenges. In 2020, only 119 tons of oyster meat were produced locally, a stark contrast to the demand and historical output. Factors such as insufficient supply of oyster seeds, pollution, and climate change have severely impacted production. Many families have abandoned oyster farming, with only around 60 remaining in traditional oyster farming areas such as Lau Fau Shan. This decline poses a threat not only to a significant part of Hong Kong’s culture but also to the ecological balance of the region.
Oysters are not just economically valuable; they also play a crucial environmental role. Serving as a natural defense against flooding, oysters help to protect Hong Kong from the impacts of climate change and extreme weather events. However, oyster reefs are among the most endangered marine habitats, with an estimated 85% loss due to commercial dredging, overharvesting, and coastal reclamation. These reefs stabilize shorelines and improve water quality, with a single oyster capable of filtering up to 200 liters of water per day.
In particular shellfish face significant threats from the rising levels of CO2 in coastal waters. Ocean acidification alters the chemistry of the ocean, drastically reducing carbonate availability. The scarcity of carbonate inhibits oysters from forming their shells, making them vulnerable to predators and hindering growth. The proteins necessary for shell formation cannot be synthesized under stress, further complicating their survival.
In response to these challenges, organizations like The Nature Conservancy (TNC) have initiated projects to restore oyster reefs, deploying two oyster reefs to help rejuvenate the local ecosystem. Additionally, efforts are underway to utilize coastal habitats and wetlands to absorb CO2 from the atmosphere, with many plant species in these areas also contributing to CO2 absorption.
In conclusion, oysters are a vital part of Hong Kong’s heritage and ecology. Addressing the threats they face is crucial not only for preserving this important industry but also for preserving the environmental health of the region. The future is in our hands.
