Seagrasses, which deliver irreplaceable "ecosystem services" to the world's coastal oceans, are in serious trouble, yet the public remains largely unaware of their problems and significance, says a UC Davis expert.

Susan Williams, director of the UC Davis Bodega Marine Laboratory, and a dozen international colleagues describe the plight of these "prairies of the seas" in the December issue of the journal BioScience.

Seagrasses are dying around the world, the authors report, beset by a host of ills caused by human impacts on the environment, including runoff from land laden with nutrients and sediments; invasive species; and a warming climate.

Despite the magnitude and rapidity of these losses, the team found that seagrasses receive far less media attention than coral reefs, salt marshes and mangroves -- even though seagrasses deliver "ecosystem services" that are at least twice as high as these other imperiled habitats. Seagrasses provide food and a home for economically valuable fish and shellfish species and for many endangered species, are areas of high biodiversity, limit erosion, and help improve water clarity.

The authors are members of the Global Seagrass Trajectories Working Group, which is supported by the National Center for Ecological Analysis and Synthesis (NCEAS). The center is funded by the National Science Foundation (NSF), UC Santa Barbara and the state of California.

Full text of "A Global Crisis for Seagrass Ecosystems" is available upon request from Sylvia Wright, swright@ucdavis.edu. (On Dec. 22, request from Susan Williams, slwilliams@ucdavis.edu.)