Unexpected expansion and regrowth in Earth's mangrove forests over the past four decades.

Abstract

Global mangrove forests have disappeared rapidly because of deforestation but have also regrown through natural regeneration and restoration. Yet their long-term trends in extent and canopy cover remain poorly quantified. By developing a global dataset of annual mangrove extent and canopy cover, we show that losses (long-term conversion) and degradation (canopy thinning) have both reduced since the 1980s and have been largely offset by regeneration and seaward expansion in the past decade. Consequently, global mangrove extent has shifted from net loss to net gain since around 2010 and changed only marginally from the 1980s to 2023 (-0.5% ± 1.4%). Beyond changes in extent, persistent mangroves exhibited sustained canopy accumulation. Our findings reveal the underestimated resilience of a highly threatened ecosystem, demonstrate early conservation effectiveness, and highlight halting deforestation as a priority for achieving conservation targets through natural regrowth.