抄録
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 Tega Marsh, a shallow wetland formed along the Tone River. The environment consisted of narrow valleys, called Yatsu cut into the Shimousa Uplands. A total of 22 Yatsu-habitats were surveyed from I May until 7 June, 1998. The gray-faced buzzard which lives at the top of the Yatsu-habitats food chain were confirmed in 9 of the 22 yatsu valleys. The results of this survey were then analyzed against several land use variables. The analyses indicate that the buzzards prefer narrower and longer valleys, and valleys with larger slope forest area. The buzzards also prefer valleys with a greater area of cultivated paddy as opposed to abandoned paddy.
