The world has increasingly relied upon protected areas (PAs) to rescue highly valued ecosystems from human activities, but whether PAs will fare well with bioinvasions remains unknown. By analyzing three decades of seven largest coastal PAs in China, including multiple World Natural Heritage and/or Wetlands of International Importance sites, we show that although PAs are achieving success in rescuing iconic wetlands and critical shorebird habitats from once widespread reclamation, this success is counteracted by escalating plant invasions. Plant invasions were not only more extensive in PAs than non-PA controls, but also undermined PA performance by, without human intervention, irreversibly replacing expansive native wetlands (primarily mudflats), and precluding successional formation of new native marshes. Exotic species are invading PAs globally. This rare study across large spatiotemporal scales highlights that the consequences of bioinvasions for humanity’s major conservation tool may be more profound, far-reaching and critical for management than currently recognized. 

Dataset 1 Classified maps of wetland types in seven largest coastal protected areas (PAs) in China

This dataset contains the classified maps of wetland types in seven largest coastal protected areas (PAs) and their non-PA controls in China.

Dataset 2 Matched protected areas (PAs) and non-PA controls for each of the seven PAs studied

This dataset contains shapefiles showing PA and their matched non-PA control sites.