二次遷移に伴うチャマダラセセリ個体数の減少 Decrease in the Number of Individuals of the Maculatus Skipper, Pyrgus maculatus BREMER & GREY (Lepidoptera, Hesperiidae) according to the Secondary Succession
In relation to the secondary succession of a pine forest after clear-cutting, changes in the number of the maculatus skipper, Pyrgus maculatus BREMER & GREY was surveyed from April, 1985 to July, 1988 in the Kisodani Valley, central Japan. The number of eggs found in this site was rapidly reduced according to the growth of Chamaecyparis obtusa ENDL., chiefly because mother butterflies hardly laid their eggs when the host plant was covered largely by other plant species. There was a tendency for the females to choose lonely host plants growing on the lands barren of other plants. This means that the skipper is mainly associated with the early stage of succession. Recently, the suitable habitat for the skipper, such as area of deforestation and domestic animal-breeding grassland, has been decreasing. I suppose this is one of the main reasons why this skipper has been less common.
蝶と蛾 40(2), 85-92, 1989