2010 Volume 50 Issue 1 Pages 55-66
We surveyed burrow size to discriminate mole species and determined the front edge of the range of Mogera wogura in 2009 in eight regions in central Honshu where this species competes with and displaces M. imaizumii. Of the 2 river basins in Nagano Prefecture where front edges had been found in 1959, the front at Agematsu Town in the Kiso River basin has advanced about 4.1 km in the past 50 years. In the other, the Tenryu River basin, a 2.4 km advance along a tributary, the Ono River and 16 km advance along the main stream were observed at the fronts. In the Fuji River basin, the front was found at first in the present survey in a gorge with flat gravelly bottom, situated about 16 km downstream of the Kofu Basin, the most upstream basin. The front in the Kanazawa Plain, Ishikawa Prefecture, did not largely change in the 11 years after the first survey in 1998. In the region ranging over Shizuoka and Kanagawa Prefectures, it was concluded that the central mountain ranging from the north to the south between the prefectures was a temporary barrier blocking the range expansion of M. wogura.
