Japan has designated two coastal areas, Shizugawa-wan (Ramsar Site no. 2358) and Kasai Marine Park (Site no. 2357), as Wetlands of International Importance, while extending a third, Lower Maruyama River and the Surrounding Rice Paddies (Site no. 2055), in order to reinforce its conservation value. This designation took place under the Ramsar Convention on Wetlands of International Importance especially as Waterfowl Habitat. More information is available here