Private Story
Wildlife Photographer of the Year
Summary
After years of degradation, a 2019 survey found that mangroves are now making a recovery in Hong Kong, going against the general trend. The global rate of mangrove decline has improved slightly - however, conservation gains are not evenly spread, nor guaranteed in the future. What’s happening in Hong Kong shows there is hope for mangroves. But much more needs to be done if we want to prevent this vital coastal ecosystem from disappearing by the end of the century.
GUARDIANS OF THE PEARL RIVER DELTA
Nestled deep within one of the many bays of the Pearl River delta, a rare patch of mangrove forest can be found hidden between the towering skyscrapers on the Hong Kong–Shenzhen border. Egrets laze in the sun as small crabs scuttle at their feet, a mountainous skyline of construction cranes looming behind them.
Mangroves are small trees that grow along the coastlines of more than 100 countries in tropical and subtropical regions. They were once widespread on the Pearl River delta and around the inlets and islands of the neighbouring Hong Kong Special Administrative Region (SAR).
Now, there are only about 60 small patches remaining in Hong Kong – the largest being at Mai Po Nature Reserve, a mangrove forest that has been designated a Wetland of International Importance under the Ramsar Convention since 1995.
It is part of a Hong Kong success story, albeit a limited one. After years of degradation, a recent survey conducted by Dr Stefano Cannicci from Hong Kong University’s Integrated Mangrove Ecology Lab found that mangroves are now making a recovery in the region.
This goes against the general trend. Over the past 50 years, 50% of the world’s mangroves have been lost. This is due to a combination of factors, including coastal reclamation, urbanisation, unsustainable aquaculture practices and pollution.
A decade ago, the rate of loss was between 1% and 2% every year. Things have improved slightly since then – the rate is now between 0.3% and 0.6% a year – thanks to stronger recognition of the ecological benefits of mangroves and expanded management and protection.
However, Associate Professor Daniel Friess from the National University of Singapore cautions against being overly optimistic, telling Science Daily that “conservation gains are not evenly spread, nor guaranteed in the future.”
What’s happening in Hong Kong shows there is hope for mangroves. But much more needs to be done if we want to prevent this vital coastal ecosystem from disappearing by the end of the century.
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