Kushiro Marsh / Kushiro Shitsugen was added to Your Favorites!
Kushiro Shitsugen NP, Hokkaido
Claim this place to tell your story your way.
Thought extinct locally, more than 10 red-crowned cranes were rediscovered in Kushiro Marsh in 1924. In 1952, Hororo Elementary in nearby Tsurui began winter feeding; the first coordinated count that year found just 33 birds.
About 6,000 years ago, today's marsh was a sea-filled bay. A sand spit sealed it around 4,000 years ago; by about 3,000 years ago, wetlands had formed, leaving the coastal lakes of Shirarutoro, Toro and Takkobu behind.
A 6th-grade class found the northern Siberian salamander near Kushiro Marsh in 1954. This Ice Age relict ranges across much of Eurasia, but in Japan it occurs only in a few northern places, including the marsh and Kunashir Island.
Yachi-bōzu, or “bog heads,” form as sedge clumps are lifted by winter frost and thawwater erodes soil around their roots. Repeated season after season, the cycle builds 40–50 cm hummocks; cold, soggy conditions leave old leaves undecomposed.
Itō (Japanese huchen) is Japan’s largest freshwater fish and a top predator in Kushiro Marsh. The Kushiro City Museum notes that big ones eat more than fish: frogs, mice and even snakes are on the menu.
For Ainu communities, the Kushiro River was a water route between the inland and the sea. About 40 chashi sites are known along its river and lake reaches; though often called forts, archaeological evidence also suggests ritual or resource-watching roles.
Near the marsh’s eastern river corridor, the Kushiro Town place name Tennel (天寧) preserves an Ainu phrase meaning “wetland path.” Other local names describe the landscape too, including a river mouth with many bird nests and a stream where wild onions grow.
Kushiro Marsh was once dismissed as “barren land.” Local researchers and conservation groups helped win recognition of its value: it became Japan’s first Ramsar site in 1980, then 7 years later the first national park centered on a marsh.
Nearby Kushiro City hosted the Ramsar Convention’s 5th global meeting in 1993. The meeting helped inspire the Kushiro International Wetland Centre, established in 1995 to connect local officials, scientists and conservation groups and share their wetland work internationally.
At Kayanuma, a straightened stretch of the Kushiro River was returned to its old meandering channel in a 2007–10 project. The restoration helped revive floodplain wetlands and varied fish habitat, while reducing sediment flowing toward the marsh’s core.
