Why Are Mangroves Important? 10 Science-Backed Facts

Many species of mangrove survive by filtering up to 90% of the salt out of seawater as it enters their roots. In addition to filtering their own water source, mangrove's unique root systems help them stay upright in soft, waterlogged soils. 

In addition to their roots, some mangrove species also have special leaves that help them thrive in salty or brackish water by secreting it out of leaf pores. Still other mangrove species store salt in older leaves or bark. When the leaves drop and the bark sheds, the stored salt is shedded with them.

Mangrove forests shelter an estimated 1,500 species (and not just fish and shellfish!). Thanks to their intricate root systems, they provide nesting, nursery and feeding grounds for many aquatic organisms — including juvenile fish of thousands of species, oysters and mussels, mudskippers, lemon sharks, and manatees. Above the ocean surface, mangroves also provide critical habitat for cranes, eagles, monkeys, and even tigers.

15% of species associated with mangroves are threatened with extinction. The UN Environment Programme's "Decades of Mangrove Forest Change" report breaks it down further:

• 50% of mangrove-associated mammals
• 22% of mangrove-associated fish
• 16% of mangrove-associated plants
• 13% of mangrove-associated amphibians
• 8% of mangrove-associated birds and reptiles.

Mangrove forests cover just 0.1% of the planet’s surface but store up to 10x more carbon per hectare than terrestrial forests. How? Mangrove trees store carbon in their leaves, and when those leaves fall off and sink into the mud and silt, they become what is known as blue carbon (carbon that is stored underwater.) 

Mangroves act as natural barriers against rising tides and storm surges. A wave passing within 100 meters of a mangrove forest can lose around 2/3 of its energy. Experts estimate that mangrove ecosystems prevent more than $65 billion in property damages and reduce flood risks for around 15 million people every year.

Mangrove forests are more ubiquitous than you might think. 123 tropical and subtropical countries have mangroves growing along their coastlines and estuaries. Although this equates to less than 1% of global tropical forest cover, mangroves provide ecosystem services to an estimated 2.4 billion people that live within 100km of coastlines.

The Asia Pacific region contains half of the world's mangrove forests. Global maps released by the Global Mangrove Watch in 2020 showed approximately 147,539 km2 of mangrove forest in the world — with 51% in the Asia Pacific, 29% in the Americas, and 20% in Africa.

Between 1996-2020, 3.4% (5,245km2) of global mangrove cover was lost. In 2023, the UN Environment Programme reported that global mangrove loss had stabilized — and some areas have regained forest cover. This is great news, but mangroves are still threatened by persistent degradation, pollution, and biodiversity loss.

80% of global fish catch is in some way dependent on mangrove forests. If you like fish on your dinner plate then you can probably thank the mangroves. Whether they are spawning grounds for ocean bound fish, habitat for shrimp, or even an important source of algae, fruit, and salt, mangroves are a vital part of the global food supply.