1985 年 35 巻 2 号 p. 235-241
TODA, Masanori J. (Inst. Low Temp. Sci., Hokkaido Univ., Sapporo). 1985. Effects of the 1977 eruption of Mt. Usu on drosophilid flies. I. August, 1978. Jap. J. Ecol., 35 : 235-241. Drosophilid vertical distribution from the ground to the canopy in a forest was compared among three places where the forest vegetation was damaged to different degrees by volcanic ash-fall. Interspecific vertical habitat segregation became more obscure in the forest which was damaged more intensively. The living space of drosophilid flies in and near the crater-basin area, where the forest canopy layer was heavily or absolutely damaged, was compressed almost into the layer of floor vegetation. In spite of the absolute damage of forest vegetation, a number of silvicolous species, both canopy and floor dwellers, persisted in the crater-basin area one year after the eruption, and some of them increased their populations, probably due to the abundant food conditions provided by damaged plants.