Effects of Taiwan Vole (Microtus kikuchii) herbivory on Yushan Bamboo (Yushania niitakayamensis) growth in Hehuan alpine meadows in Taiwan

Background/Question/Methods   Taiwan vole (Microtus kikuchii) is the most dominant small mammal, and Yushan bamboo (Yushania niitakayamensis) the most dominant plant in Hehuan alpine meadows in Taiwan, the bamboo is strongly preferred by the voles. The differential feeding on different bamboo parts could have different fitness consequences for the plant. We perform laboratory and field experiments to understand the effects of feeding by the vole on the Yushan bamboo. During the laboratory trials, we provided 10 g each of bamboo parts (rhizome, cane, leaf, and shoot) and 15 g each of control food (yam and oat) to voles simultaneously for 12h. The trials were repeated in January, May, and October. During the field manipulation, we manipulated trios of 50 × 50 cm2 bamboo plots in the field: (IL) increase light treatment; (DL) decrease litter treatment; and (C) control with 12 replicates.

Results/Conclusions   The results indicated that voles prefered different parts of Yushan bamboo in different seasons. They preferred leaves in January and October. During May, the preference rank was shoot > leaf > rhizome > cane. The feeding preference was positively related to the amounts of minerals, fiber (ADF), and crude protein. The field manipulation showed that the foraging of the voles generally decreased the number of Yushan bamboo stems, thus coverage, yet increased the number of new shoots. The foraging of Taiwan voles could facilitate the growth of younger and healthier Yushan bamboo.