Mangroves Make Global Comeback

Mangrove forests, long considered among the world’s most threatened coastal ecosystems, are showing signs of a remarkable recovery.

A new Tulane University study based on four decades of satellite data found that mangroves are no longer declining globally. After decades of losses from deforestation and coastal development, gains from natural regeneration and expansion have begun to outpace losses.

“We’re finally seeing a global turning point for mangroves,” said lead author Zhen Zhang, a postdoctoral scholar at Tulane School of Science and Engineering.

Between the 1980s and 2010, the world lost nearly 2,900 square kilometers of mangrove forest. But over the past 16 years, that trend has reversed. By 2023, the net decline over the full four-decade period had narrowed to about 1% — far less than previously estimated.

Healthier, denser mangrove forests capture more carbon, support fisheries and buffer coastlines from storms. And the rebound reflects the growing impact of conservation policies and restoration programs worldwide.

“What we’re seeing now is a real shift,” said Daniel Friess, Cochran Family Professor of Earth and Environmental Sciences at Tulane and director of The Mangrove Lab.

Recovery is being driven by both conservation efforts and natural processes. Mangroves are reclaiming abandoned aquaculture ponds and spreading across newly formed mudflats in sediment-rich river deltas.

Along the Gulf Coast, warming temperatures are helping mangroves expand northward. In Louisiana’s Mississippi River Delta, mangrove cover began increasing in the late 1990s, with stronger growth after 2012.

But researchers caution that the comeback remains fragile. Deforestation continues in some regions, and a severe freeze in Texas in 2021 caused a sharp decline in mangroves there, showing how quickly temperature extremes can erase gains.

“The most immediate and effective way to protect mangroves is to stop deforestation,” Zhang said.