Japan has lost 60 % of its marshes in the twentieth century. About 86 % of all marshes in Japan today can be found in Hokkaido, the northernmost main island of Japan. However, Hokkaido has lost over 100,000 ha of marshes in the past. Kushiro Marsh is the largest remaining marsh in Japan, providing habitats for endangered species such as Red-crowned crane Grus japonensis and Siberian salamander ... [Show full abstract] Salamandrella keyserlingii. The other principal marsh areas in Hokkaido are Kiritappu and Bekambeushi marshes in the eastern part and Sarobetsu marsh in north. The increasing deer population in Hokkaido marshes has become a serious problem.