Seagrass meadows—marine ecosystems that support biodiversity and provide a range of other ecosystem services—are globally in decline (1). Many species use seagrass meadows as foraging grounds, spawning grounds, and shelter, including migratory species such as brant geese, the dugong, and the green turtle (2, 3). Conserving these valuable ecosystems will require comprehensive global maps of their locations (4) and a better understanding of the species that depend on them (3).
