Located near Mount Takadate, the Site comprises two near-natural ponds which were built for irrigation about 400 years ago. The Site is globally important for the endangered Japanese eel (Anguilla japonica) and Shinai top-mouth gudgeon (Pseudorasbora pumila), and for wintering waterbirds. Some 50,000 waterbirds have been recorded at the Site, including about 15% of the flyway population of the Tundra swan (Cygnus columbianus). White-tailed sea eagle (Haliaeetus albicilla) and Steller’s sea eagle (Haliaeetus pelagicus) are also present, both of which are listed as vulnerable on the National Red List and are included in the List of Natural Monuments of Japan. East Indian lotus (Nelumbo nucifera) cover most of the water surface, in particularly of the Oyama Kami-ike pond. The Site has been designated as a Special Protected Zone within the National Wildlife Protected Area. There is a management plan in place.