The cost of restoring mangroves
Mangroves, the amphibious forests that fringe tropical and subtropical coastlines, are ecological powerhouses. They buffer communities against storm surges, support fisheries, and sequester carbon at rates that rival their terrestrial counterparts. Yet despite growing recognition of their value, mangroves remain imperiled. About 35% of global cover was lost in the late 20th century, largely to aquaculture and coastal development.
New research offers the most comprehensive look yet at the cost of reversing that damage. Drawing on nearly 250 projects and dozens of data sources, researchers have created the first global model of site-specific mangrove restoration costs. They find a median implementation cost of $8,143 per hectare, with wide variability: From just $9 to over $700,000. Site conditions matter. Rehabilitating abandoned shrimp ponds tends to be cheap; replanting eroded or hydrologically disrupted coastlines is far pricier.
Indonesia, with its vast archipelago and degraded deltas, holds the greatest potential. At least 204,000 hectares could be restored at less than $10,000 per hectare—making it a focal point for meeting national and international targets. Globally, 1.1 million hectares of mangroves could be restored for $10.73 billion, or roughly what Americans spend on pet food every three months. That could remove up to 0.93 gigatons of CO₂ from the atmosphere, at an average cost of $11.49 per ton.
Such figures are competitive in the world of carbon markets, where blue carbon credits—those derived from coastal ecosystems—are gaining traction. But for now, the market is nascent.
Carbon finance alone is unlikely to underwrite the global mangrove revival. Opportunity costs—such as forgone aquaculture profits—could more than double restoration expenses. And the true success of such efforts will depend not just on trees planted or credits sold, but on long-term governance, local engagement, and ecological resilience.
Still, this cost model offers a tool for prioritizing investment. Where resources are scarce and climate ambitions high, identifying the most cost-effective hectares could help steer restoration efforts toward both fiscal prudence and environmental payoff.
CITATION: Garrett M. Goto et al. Implementation costs of restoring global mangrove forests. One Earth
Volume 8, Issue 7, 18 July 2025, 101342. https://doi.org/10.1016/j.oneear.2025.101342