Mangrove forests: 10 things you should know

What are mangroves, and why are they one of the most irreplaceable ecosystems on Earth? Read on for our incredible mangrove facts…

10 facts about mangroves

1. Mangroves live where land meets sea 

Mangroves are trees and shrubs that have adapted to live in the intertidal zones of coasts, which are flooded with sea water at high tide. Unlike most plants, they’re tough enough to survive even in salty conditions and, in some cases, with their roots regularly submerged in water. There are around 80 different species of mangrove trees worldwide.

2. Mangrove forests circle the planet

Mangrove forests can be found on tropical and subtropical shores, lagoons and estuaries around the world, from the Everglades National Park in North America to the Sundarbans Forest Reserve spanning Bangladesh and India (the largest mangrove forest in the world across country borders). Southeast Asia is home to almost a third of all mangroves, with Indonesia alone having a fifth of the global total.

3. Mangrove trees have some amazing adaptations

A distinctive feature of many mangrove trees are their specialised root systems that help them thrive in waterlogged, oxygen-poor soils. Mangrove roots anchor the trees in place amid shifting tides, sometimes giving them the appearance of standing on stilts. 

The red mangrove develops aerial roots that grow down from its trunk and branches, circulating oxygen around the tree. The black mangrove produces small roots that grow up above the water level, like snorkel tubes, to take in oxygen from the air.

4. They’re also salt-water specialists

Salt can kill off many plants, but mangroves are brilliant at absorbing sea water and turning it into fresh water. Some mangrove trees can filter out as much as 90% of the salt through their roots. Others excrete salt through their leaves, or store salt in older leaves and branches that are the first to be lost.

5. Mangrove forests are hotspots for biodiversity

Muddy yet magical places, mangrove habitats shelter an astonishing variety of life. Animals that live in mangrove forests include Bengal tigers, saltwater crocodiles, hawksbill turtles, proboscis monkeys, mangrove finches and pygmy three-toed sloths. Mangrove forests are also important stop-overs for migratory birds, and provide breeding, nursing and feeding grounds for fish (including sharks), shrimps, crabs and other aquatic species.

6. They’re even good for coral reefs

Mangroves and coral reefs are both important habitats for biodiversity, and healthy mangrove forests are good news for local reefs. Mangrove roots trap sediments that might otherwise wash away and smother corals, while the shade provided by mangrove trees has been shown to protect reefs from solar radiation and from the rising sea temperatures associated with climate change.

7. Mangroves support and protect coastal communities

Many coastal dwellers worldwide depend on mangrove forest for their food and livelihoods, with 4.1 million people earning their living as mangrove fishers. And thanks to mangroves’ role as spawning grounds and nurseries for commercially important fish and seafood species, they also support the wider fishing industry. As much as 80% of global fishing catch may depend directly or indirectly on mangrove habitats.

For coastal communities, mangroves also provide a buffer against the storms and tsunamis that are intensifying due to climate change. An 80-metre-wide stretch of mangrove trees can reduce storm wave heights by 80%. It’s estimated that mangroves are five times more cost effective than man-made sea barriers in protecting communities from storm surges and tsunamis.

8. Mangrove forests fight climate change

Mangrove trees and the soil beneath them are incredibly effective at capturing and storing carbon, making mangrove forests a powerful ally against global warming. They’re estimated to store three to four times more carbon than other types of tropical forest.

9. The world’s mangroves are under threat

Mangrove forests are one of the most threatened ecosystems on Earth. Between a fifth and a third of the planet’s mangrove habitat has already been lost. Restoring mangroves, and supporting the communities and species that live in and around these precious coastal forests, is an important part of our conservation work in Asia.

10. Mangroves can bounce back – with our help

While most mangrove loss is driven by humans, people also have the power to help save these incredible wetlands. It’s estimated that more than 8,183km2 of mangrove habitat lost since 1996 is restorable. We’re working to do exactly that in the Philippines, where we’ve already replanted more than one million mangrove trees.