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  • Country: 
  • Site number: 
  • Area: 
    2,861 ha
  • Designation date: 
  • Coordinates: 
    36°14'N 139°41'E
Materials presented on this website, particularly maps and territorial information, are as-is and as-available based on available data and do not imply the expression of any opinion whatsoever on the part of the Secretariat of the Ramsar Convention concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries.


Watarase-yusuichi. 03/07/12; Ibaragi, Tochigi, Gunma, Saitama; 2,861 ha; 36°14'20"N 139°40'56"E. National Wildlife Protection Zone. A natural river flood plain where the Watarase, Uzuma and Omoi rivers meet and includes the Watarse reservoir, an artificial retarding basin surrounded by an embankment managed mainly for flood control. Located 60 km north of Tokyo, it is representative of a Phragmites australis-dominated low moor wetland in the Japanese Evergreen Forest biogeographic ecoregion. The extensive reedbed is one of the largest in the biogeographic region and supports a diversity of wetland flora and fauna. The site has an important flood control function by retarding the flood water from the rivers that flows into the site, and then slowly releasing the water into the Tone River that flows downstream. It is also used for fisheries, recreation, and environmental education. The wetland is at risk of drying up due to excess deposits of earth and sand and is being maintained through excavation since 2010. Ramsar Site no. 2061. Most recent RIS information: 2012.

Administrative region: 
Honshu Island

  • National legal designation: 
    • National Wildlife Protection Zone
  • Last publication date: 


Ramsar Information Sheet (RIS)

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