The Japanese hare (Lepus brachyurus) gnawed and fed on pruned branches in the 8-year-old Hinoki (Chamaecyparis obtusa) plantation just after pruning. Although the pruning was carried out on 13 and 19 November 1987, debarkation occurred only towards the branches pruned on 13 November. Judging from the fecal pellet density, a few hares fed mainly on a part of barks of the branches. The ratio of the number of debarked branches to the total number of branches was ca. 7%. The mean number of debarkation wounds per branch was 2.2. The mean size of wounds was 287.2 mm^2 in area (58.0 mm in length, 6.5 mm in width). A total of the bark intake was estimated at 14.9 g in wet weight (7.5 g in dry weight), which occupied 4-8% of the daily feed intake per hare. Such a feeding behaviour seems to be a transient action against the planted young Hinoki and its pruned branches, both of which are relatively preferred by the hare when available food is scanty.

View full abstract

Clipping damage to 5 species of broadleaf tree seedlings (1 m in height, 1 cm in basal diameter) planted in a cutover area (20×30 m) of a 25-year-old Hinoki Chamaecyparis obtusa plantation was brought about by the Japanese hare Lepus brachyurus during May-October, 1986. Almost all the stems and twigs clipped were left uneaten. Judging from the fecal pellet density, a few hares invaded from the secondary stand adjacent to the planted area, where Urajiro Hicriopteris glauca was a dominant floor plant. The clipping damage occurred for every tree species planted in the area ; however, the ratios of the clipping damage in Kobushi Magnolia kobus (100 %), Konara Quercus serrata (97 %), Yamazakura Prunus jamasakura (87 %) and Keyaki Zelkova serrata (62 %) were significantly higher than that (20 %) in Yamamomiji Acer palmatum (κ^2 test, P<0.001). Although such a clipping behaviour towards trees is a common character in the family Leporidae, the reason why the hare clips trees without eating has almost remained unsolved. There seems to be a considerable possibility of the destructive damage caused by the hare to the broadleaf tree seedlings planted in such an environmental condition.

View full abstract

[in Japanese]

View full abstract