Impact of bark stripping by sika deer, Cervus nippon, on subalpine coniferous forests in central Japan

We investigated the effect of bark stripping by sika deer, Cervus nippon, o n forest regeneration in subalpine coniferous forests on Mt. Ohdaigahara an d in the Ohmine Mountains of central Japan. Bark stripping by sika deer occ urred in five major tree species: Abies homolepis; Abies Veitchii; Tsuga di versifolia; Picea jezoensis var, hondoensis: and Chamaecyparis obtusa. The percentage of damaged trees on Mt. Ohdaigahara was higher than in the Ohmin e Mountains. probably because of the higher deer density. On Mt. Ohdaigahar a, the DBH distributions of stems for P. jezoensis var, hondoensis, A. homo lepis. T. diversifolia and C. obtusa were bell-shaped with fewer smaller an d larger trees. On the other hand, in the Ohmine Mountains the distribution s for P. jezoensis var. hondoensis and A. Veitchii showed a reverse-J shape d with more smaller trees. Larger overstory conifers on Mt. Ohdaigahara wer e killed by bark stripping when 100% barked. although in the Ohmine Mountai ns ca. 50% of the trees survived even when 100% barked. After the disappear ance of the overstory conifers on Mt. Ohdaigahara, the dwarf bamboo, Sasa n ipponica, expanded into the forest Boor due to changes in light reaching th e forest Boor. Since S. nipponica is the main forage of deer in this area, this increase caused a corresponding increase in the deer population, which in turn, could cause a further decline in the coniferous forests, (C) 2001 Elsevier Science B.V. All rights reserved.