Yudonuma Pond

About Yudonuma Pond

A brackish, lagoon-origin lake on the Pacific coast of Toyokoro Town. In the 1991 survey it ranked second in Japan after Lake Mashu among unmodified lakes with a shoreline of 5 km or more (17.8 km). Recorded species include Japanese smelt, white-spotted char, herring and Sakhalin taimen, and wigeon and tufted ducks in winter. Both the 1977 aerial photo and recent photos show a narrow sandbar separating the lake from the sea.

Sources: Environment Agency of Japan, Lake Survey Report (1993), Environment Agency of Japan, Lake Survey Report: Data Appendix (1993), This site: comparison of 1970s GSI aerial photos with recent GSI imagery (sources in Japanese)

Lake data

Area

4.43 km²#19 in Hokkaido

Maximum depth

3.5 m#51 in Hokkaido

Average depth

1.3 m

Surface elevation

5 m

Transparency

1.8 m#24 in Hokkaidoas of the 1991 survey

Origin

Lagoon-origin lake

Lake type

Dystrophic

Fresh or brackish

Brackish

Freezing

Freezes in winter

Unmodified lake

Yes (shore entirely natural)

Natural park

None

Lake number

0770number in the national lake survey

Sources: Geospatial Information Authority of Japan, Area Statistics of Prefectures and Municipalities 2026 (as of July 1), Environment Agency of Japan, 4th National Survey on the Natural Environment: Lake Survey Report (1993). Area and depth use newer figures from the Geospatial Information Authority of Japan where available. Origin, lake type, transparency, freezing and unmodified status are as of the 1991 survey.

Themes that include Yudonuma Pond

• Lagoon-origin lakes
• Dystrophic lakes
• Brackish lakes
• Unmodified lakes