| Affiliation: | (1) Kiso Biological Station, Kyoto University, Kiso Fukushima, Nagano 397-0000, Japan;(2) Center for Ecological Research, Kyoto University, Otsu, Shiga 520-2113, Japan;(3) Museum of Nature and Human Activities, 6 Yayoiga-oka, Sanda, Hyogo 669-1546, Japan;(4) Research Institute for Humanity and Nature, Kamigyo, Kyoto 602-0878, Japan;(5) Center for Marine Environmental Studies, Ehime University, Matsuyama, Ehime 790-8577, Japan;(6) School of Human Sciences, Sugiyama Jogakuen University, Nisshin, Aichi 470-0131, Japan |
| Abstract: | We examined the effects of oxygen availability, which has been viewed as a minor factor in streams, on the seasonal and spatial microhabitat distribution of a stonefly. Surveys were conducted in winter and summer in a mountain stream by collecting stones from the streambed and determining the presence or absence of the insect. At each stone sampling, we also measured physical conditions. The probability of the stonefly presence increased significantly with current velocity in summer, but not in winter. Because current influences oxygen renewal rates, our results suggest that the distribution of the insect could be restricted by oxygen. |
