English: MOSS LANDING, CA — Elkhorn Slough joins 38 other wetland sites in the United States — including the San Francisco Bay estuary — and more than 2,330 sites worldwide, in a network of globally important wetlands designated under the world’s oldest international environmental treaty. The Convention was signed in Ramsar, Iran in 1971, and almost 90 percent of U.N. member states have since adopted the treaty.

To be designated as part of the Ramsar Convention on Wetlands of International Importance, a wetland site must fulfill at least one of nine criteria, including hosting more than 20,000 shorebirds at a time, serving as fish nursery habitat, and supporting threatened species. Elkhorn Slough met all nine criteria. The designation was approved by the U.S. Department of State and the U.S. Fish and Wildlife Service this year.

The Elkhorn Slough is a seasonal estuary rich with intertidal marshes, mudflats, eelgrass beds and oyster communities that nourish wildlife. More than 340 species of birds, 100 species of fish, including bat rays and leopard sharks, and more than 500 species of invertebrates have been documented in the watershed. Its distinctive estuarine communities are among the rarest and most threatened habitats in California, and are home to more than 140 Southern sea otters that feed, rest, and raise their pups in these wetlands.

Photo by Hazel Rodriguez/USFWS