Key Biodiversity Areas

Lake Biwako (15168)
Japan, Asia

Site overview


KBA status: confirmed
Year of last assessment: 2011
National site name: Lake Biwako
Central coordinates: Latitude: 35.2500, Longitude: 136.0833
System: freshwater, terrestrial
Elevation (m): 0 to 85
Area of KBA (km2): 675.67787
Protected area coverage (%): 98.43
KBA classification: Global/Regional TBD
Legacy site: Yes

Site details


Site description: Lake Biwako is 670 km2 and the largest lake in Japan. In addition to Northern Lake (613 km2 - average depth of 43 m) and Southern Lake (57 km2 - average depth of 4 m), which are divided by Biwakoohashi Bridge, there are many shallow marsh grounds called Naiko (inner lake) scattered around Lake Biwako, and they form habitats for wildlife connecting each other. The environmental elements are divided into two parts, a deep and vast offshore area and a shallow water zone along the coastline. The zone is rich in environment with aquatic plants such as Phragmites australis communities, sand beaches, rocky coasts and artificial banks. Surrounding areas are also agricultural fields, forests and urban areas. About 460 large and small rivers flow into Biwako, and sandbanks are well developed at the mouths of large rivers such as the Azumigawa river, the Anegawa river, the Aichigawa river and the Yasugawa river. There are five islets in the lake, Okishima, Chikubujima, Takeishima, Okinoshiroishi and the artificial Kihan-to.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance because it meets one or more previously established criteria and thresholds for identifying sites of biodiversity importance (including Important Bird and Biodiversity Areas, Alliance for Zero Extinction sites, and Key Biodiversity Areas)

Habitats


IUCN HabitatCoverage %Habitat detail
Wetlands(Inland)100

Threats


Threat level 1Threat level 2Threat level 3Timing
Natural system modificationsDams & water management/useDams (size unknown)Ongoing
Invasive & other problematic species, genes & diseasesInvasive non-native/alien species/diseasesNamed speciesOngoing
PollutionDomestic & urban waste waterType Unknown/UnrecordedOngoing
Climate change & severe weatherTemperature extremesOnly in the future
Climate change & severe weatherStorms & floodingOngoing
Human intrusions & disturbanceRecreational activitiesOngoing
Residential & commercial developmentHousing & urban areasOngoing