Mangrove forests form a unique wetland ecosystem, inhabiting the edge of land and sea, thriving in seawater. Mangroves – trees and shrubs which live in intertidal zones – are found along tropical and sub-tropical coastlines in many Commonwealth countries.
Mangroves aren’t lack the majesty of their terrestrial counterparts; they are dark and can smell bad. Nevertheless, they play a vital role in the ecology, sustainability and security of coastal communities. For example, they are one of the most cost-effective methods of coastal disaster risk management by reducing the effects of coastal flooding, storms, and erosion. Mangroves provide a safe harbour –food and protection– for young marine life before they are ready to move further out to sea or populate coral reefs. As well as supporting and protecting marine life, mangroves provide nesting and migratory sites for hundreds of species of birds which flourish among their branches. Additionally, they make a critical contribution to climate regulation through carbon capture. Unlike terrestrial forests which store most of their carbon in their trunk and branches, mangroves store most carbon in their root systems and neighbouring soil, acting as carbon ‘sinks’, locking it away for generations. Also unlike their terrestrial counterparts, mangrove forest fires are seldom a danger, and hence the carbon capture is much more secure in the long-term. Yet despite their many benefits these ‘blue forests’ are in decline.
Mangrove trees are being cut back for firewood, coastal developments, and to make way for shrimp farming, or falling victim to pollution from inland sources such as discarded plastics.
Over the past four decades 35% of global mangrove forests have been destroyed. This degradation of mangrove forests has a knock-on effect on some of the world’s most endangered species which rely on them for habitat such as the proboscis monkey and the Bengal tiger.
But there is hope for the mangroves. In addition to their contribution to mitigating the effects of climate change, restoring mangroves has proved to be one of the most cost-effective methods of coastal risk reduction which may provide a much-needed incentive to preserve these ‘rainforests of the sea’.