Kasai Marine Park

Higashi Nagisa of the Kasai Marine Park that is located near city area

Kasai Marine Park

  • Country: 
  • Site number: 
  • Area: 
    366.9 ha
  • Designation date: 
  • Coordinates: 
    35°37'N 139°51'E
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The Site, a brackish wetland in the estuaries of the Arakawa and Kyuedogawa Rivers in the Tokyo Bay, was created in 1976 to restore and conserve the natural ecosystem which was lost due to development activities such as land reclamation. It features human-made beaches known as Nishi Nagisa (west beach) and Higashi Nagisa (east beach), which were constructed by placing U-shaped training dikes to create foreshore tidal flats. Connected to Higashi Nagisa is the natural Sanmaizu tidal flat; and while Nishi Nagisa is designated for recreation, Higashi Nagisa is a National Wildlife Protection Area providing habitats for wildlife. Greater scaup (Aythya marila) and great crested grebe (Podiceps cristatus) winter there, and it is also a key habitat for little tern (Sternula albifrons) and some Anatidae species. Overall, about 126 species of birds have been observed on the Site. It has become an important wetland for biodiversity conservation in a highly developed urban context and an example of coexisting natural and urban environments. Following the expansion of Higashi Nagisa between 1986 and 2008, the number of coastal plant species in the Site has increased.

Administrative region: 
Tokyo Metropolis

  • National legal designation: 
    • National Wildlife Protection Area, Special Protection Zone - Kasai-oki Sanmaizu National Wildlife Protection Area, Kasai-oki Sanmaizu Special Protection Zone
  • Last publication date: 


Ramsar Information Sheet (RIS)