Relationships between Browsing on Dwarf Bamboo (Sasa nipponica) by Sika Deer and the Structure of Ground Beetle (Coleoptera: Carabidae) Assemblage

Abstract

111 119. An overabundance of Sika deer Cervus nippon at Mt. Ôdaigahara, in west-central Japan has necessitated the introduction of exclusion fences to protect forest decline from excessive feeding damage. However, the effect of these exclusion fences on the biodiversity of arthropods within the protected areas has not been investigated. In this study we examined the relationships between the volume of dwarf bamboo Sasa nipponica , the major forage for the deer, on associated with browsing by deer and the structure of ground beetle assemblage. Both inside and outside of the exclusion fences, pitfall traps were setup in plots that had been assigned treatments of either no treatment control or artificial clipping of dwarf bamboo. Ground sticky traps were also set up in each plot to sample the abundance of small animals as the diet of ground beetles. Bamboo volume did not reltate to abundance, species richness, or diversity of the ground beetle assemblage. The abundance of the most dominant beetle species, Leptocarabus kumagaii, increased positively in response to both bamboo volume and the abundance of Orthopterans. The second most dominant species, Pterostichus fujitai, did not relate to bamboo volume, but decreased in abundance in relative to the propotions of open canopy. The third most species, Pterostichus microcephalus, decreased in abundance relative to bamboo volume, but increased positively in response to the abundance of Collembolans, Dipterans, and Hymenopterans. These results suggested that reduction of bamboo volume by browsing of deer did not affect the diversity of ground beetle aseemblage but affected its structure.

Effects of Deer Grazing on Vegetation and Ground-Dwelling Insects in a Larch Forest in Okutama, Western Tokyo

“…As many carabid beetles are flightless and prefer more stable habitats [42][43][44], they would provide a good reflection of differences in microenvironments. The results of our study and of a study conducted in western Japan [31] suggest that deer grazing indirectly decreases carabid beetles, in contrast to results obtained in boreal forests [25][26][27][28]. It is noteworthy that more carrion beetles, dung beetles, and camel crickets were collected outside the exclosure than inside (Table 4).…”

“…The habitat preferences of Japanese carabid beetles are not well known, but because forest vegetation predominates and the summer climate is humid in the Japanese archipelago, it is likely that most carabid beetles would prefer a habitat where litter is abundant and the microclimate is more humid and stable. A study on the indirect effects of sika deer on ground-dwelling insects in western Japan showed that a species of large carabid beetle, Carabus kumagai (23-36 mm in length), was more abundant in a habitat containing more Sasa nipponica, a dwarf bamboo [31]. As many carabid beetles are flightless and prefer more stable habitats [42][43][44], they would provide a good reflection of differences in microenvironments.…”

“…Some studies reported an increase in carabid beetles as a result of ungulate grazing [25][26][27][28], whereas others reported no effect [29,30]. In Japan, sika deer grazing decreased Sasa nipponica, a dwarf bamboo, but did not affect carabid beetle populations [31].…”

Carabid beetles (Coleoptera:Carabidae) in coniferous plantations inHokkaido,Japan: effects of tree species and environmental factors

“…Ueda et al . () noted that Carabus ( Leptocarabus ) species do not prefer a habitat where the percentage of foliage cover is low. The result that Carabus species were abundantly collected in Japanese spruce suggests that Japanese spruce presents a favorable habitat for large species among the three plantations.…”

Nitrogen leaching from surface soil in a temperate mixed forest subject to intensive deer grazing

“…In 1997, ten plots were constructed for a research project to estimate the effects of deer grazing on plants, soil, and insects (e.g., Ito and Hino 2004;Furusawa et al 2005Furusawa et al , 2011Ueda et al 2008Ueda et al , 2009. Each deerexclusion plot was enclosed by a 2-m-high fence to keep deer out (plot size, 5 9 10 m).…”