Identification of Potential Habitats of Gray-faced Buzzards in Yatsu Valleys Based on DEMs and Vegetation Data

Abstract

The distribution of Gray-faced Buzzard Butastur indicus was studied in a countryside environment in northern Chiba-Prefecture, central Honshu, Japan. The study area was located in the watershed of Inba Marsh, a shallow wetland formed along the Tone River. The environments consist of narrow and shallow valleys known as yatsu of yato dissecting into the diluvial uplands. The landscape patterns of yatsu valleys are classified using 50m-DEMs (50m-Digital Elevation Models) and digitized vegetation data. Gray-faced Buzzard habitats are related to the followings, 1) the landscape pattern of valleys which paddy in the valley floors and wood in the valley walls, 2) the number of adjacent land use of wood and paddy, 3) the width of valley floors. Potential habitats of Gray-faced Buzzard are estimated in the watershed in 20km×30km area.