The world's wetlands provide an estimated $39 trillion in benefits every year, yet more than one-fifth of them have vanished since 1970 — and a fifth of what remains could disappear by 2050 without urgent investment.
Wetlands — marshes, swamps, peatlands, floodplains, and shallow lakes — regulate water supply, store carbon, filter pollutants, and support a disproportionate share of global biodiversity relative to their land area.
Since 1970, an estimated 411 million hectares of wetlands have been lost worldwide, a 22% decline in global wetland extent, continuing at an ongoing loss rate of roughly 0.5% per year. Around 25% of remaining wetlands are classified as being in poor ecological condition, a share that is increasing — including in 12% of formally protected Ramsar sites.
Source: Ramsar Convention, Global Wetland Outlook 2025Restoration investment in wetlands is estimated to generate $5–35 in ecosystem service benefits per dollar spent — among the highest returns identified for any nature-based conservation intervention — yet current global conservation funding remains far below what the Ramsar Convention's own analysis estimates is required.
Historical wetland extent prior to systematic mapping (pre-1970s) relies on reconstructed estimates rather than direct measurement, meaning the true long-term scale of wetland loss, which likely predates 1970 in many regions, is probably understated by the commonly cited 411-million-hectare figure.