Credit: J. FREUND

Seagrass meadows around the world are in dire shape, according to the first comprehensive global assessment of these economically and biologically essential areas.

More than a quarter of all seagrass meadows have disappeared in the past 130 years, says a new synthesis of quantitative data from 215 sites (M. Waycott et al. Proc. Natl Acad. Sci. USA doi:10.1073/pnas.0905620106; 2009). The rate of decline has grown from less than 1% per year before 1940, to 7% per year since 1990.

As well as supporting wildlife such as dugong (Dugong dugon, pictured) and green turtles (Chelonia mydas), seagrass meadows also serve as a vital nursery for fish, supporting populations for coral reefs and commercial fisheries.