Lake Utonai is a freshwater lake located on the eastern tip of Tomakomai. Surrounding the lake are colonies of Manchurian wild rice, reeds, and groves of Japanese alder. Greater white-fronted geese, swans and other migratory birds alight on the lakeside to rest and feed. Lake Utonai was the first to be designated a bird sanctuary by the Japan Birch-watching Society in 1981. In 1991 it became the fourth wetland area in Japan to become a designated wetland under the protection of the Ramsar Convention. There are many ways to enjoy the lake year-round, such as birdwatching, footpaths, opportunities to observe nature, and interacting with nature and wild birds.