Lake Kutcharo
The site is considered especially important for the tundra swan and the white-tailed eagle. Many varieties of ducks use the site, as well, with 50,000-60,000 visiting the lakes annually. A bird banding facility and an observation center are found at the site. Etymology and geography. The lake name is based on the Ainu "kut-char" (クㇳチャㇻ), meaning "marsh water outlet". Lake Kutcharo consists to two interconnected smaller lakes, the smaller northern one called and the larger southern one called . Six rivers flow into Konuma, which flows into Onuma via a small waterway at the northern end  of Onuma. Additionally, two rivers flow into Onuma. The outlet—located at the upper southeast corner of Onuma—flows into the Kutcharo River which flows about east where it converges with the Tonbetsu River about before it empties into the Sea of Okhotsk. Tides can cause some seawater inflow into Onuma. The lake and the surrounding area was designated a Ramsar site in Japan in July 1989. Fauna and flora. Lake Kutcharo is considered an import wintering and resting site in the migration of tundra swans, with 6000–10,000 visiting each year. More than 290 species of birds are found in  and around the lake, especially ducks. About 50,000-60,000 ducks visit annually. The site is important for the conservation of the endangered white-tailed eagle. The lake is surrounded on three sides by forests of firs and spruces. "Ruppia occidentalis" is known to grow in the shore area. Facilities. The Kutcharo-ko Waterfowl Observation Center is located on the southern shore of Onuma, and a bird banding station is located at the southern end of the connecting waterway between the smaller lakes. In popular culture. Lake Acuity in "Pokémon Diamond and Pearl" and "Pokémon Platinum" is based on this lake  as the Sinnoh region is a fictionalized version of Hokkaido.