Senegal mangrove restoration project sold ghost carbon credits after overstating tree survival and carbon storage

A major mangrove restoration project in Senegal, launched in 2008 and designed to sell blue carbon credits, overstated its climate benefits because more than a third of the planted areas failed completely. Researchers found that only 18% to 20% of planted mangroves survived across the 10,000-hectare project, yet carbon credits were calculated as if all trees grew. This led to an overestimation of about 168,000 tons of CO2 storage, representing roughly $2 million to $7 million in potentially invalid credits. The project, run by NGO Oceanium with French corporate partners, planted mangroves in unsuitable salty mudflats far from tidal channels. Local communities received only 5% of the $4.4 million meant for their work, and some lost land. The certification body Verra and monitoring firm Agresta approved credits based on flawed assumptions, failing to account for widespread die-off. The author argues that for nature-based carbon projects to be credible, independent verification and honest accounting of failure rates are essential.