Changes in the composition of wild murid rodents obtained from the data for prediction of pest density in the national forests of hokkaido japan
Nakatsu, A.
Annual Report of the Hokkaido Branch Forestry and Forest Products Research Institute 6: 67-71
1988
Accession: 007094618
The relationship between the component ratio and the population change of wild murid rodents obtained from the data reported regularly for the prediction of pest density in the plantations of national forests in autumn during the last eighteen years, was investigated in each regional forest office of Hokkaido. On the whole. the proportion of Clethrionomys rufocanus bedfordiae to all the number of rodent species captured in the present investigation showed a tendency to become low because of the decrease of the vole pest number. In Hokkaido Regional forest Office and Asahikawa Regional Forest Sub-Office area, the proportion of voles, C. r. bedfordiae to all species was reduced owing to the increase of the number of Apodemus Speciosus ainu and A. peninsulae giliacus in the former area, as well as owing to the decrease of the number of C. r. bedfordiae in the latter area. However, in the Kitami and Obihiro Regional Forest Sub-Offices, it became high due to the increase of the vole pest number in the former area, as well as due to the decrease of the number of A. s. ainu and A. p. giliacus in the latter area. Accordingly, it was revealed that the plantations investigated, at least in this study, in each regional forest office have changed from the suitable environment for C. r. bedfordiae into that for Apodemus genus in the process of the following regional fores office, i.e. Obihiro-Kitami-Asahikawa-Hokkaido-Hakodate.