- 動物学雑誌 (ISSN:00445118)
- vol.72, no.5, pp.133-138, 1963-05
From April, 1962 to March, 1963, the authors collected small mammals (Rodentia and Insectivora) monthly by snap traps in the subalpine forest zone (Tsugadiversiforia-Abies Mariesii forest zone, alt. 1,300-2,400m) on Mt. Yatsugatake in Honshu. Total number of captured mice and voles was 961 with the following proportional breakdown: Rattus rattus 1, Apodemus speciosus 14, Apodemus argenteus 308, Clethrionomys andersoni 616, Anteliomys smithii 20, Microtus montebelli 2. The number of moles and shrews taken was 231 with the following breakdown: Euroscaptor mizura 1, Urotrichus talpoides hondonis 18, Dymecodon pilirostris 151, and Sorex shinto shinto 61. Rattus rattus and Microtus montebelli were found in this area. Apodemus speciosus and Urotrichus talpoides hondonis were only found in the lower part of this grassy area. On the other hand, Apodemus argenteus, Clethrionomys andersoni, Anteliomys smithii, Dymecodon pilirostris, Sorex shinto shinto were widely found in this forest zone. It was noted that the largest number of Apodemus argenteus appeared in spring, but the peak of Clethrionomys andersoni was seen from autumn to winter (Fig. 2). The average embryo sizes of each species were as follows: Apodemus speciosus 5.7, Apodemus argenteus 3.9, Clethrionomys andersoni 3.3, Anteliomys smithii 3.5, Microtus montebelli 3.0, Urotrichus talpoides hondonis 4.5, Dymecodon pilirostris 3.5, Sorex shinto shinto 3.7. The highest capture rate (number of captured small mammals/no. of set traps) occurred in October and the lowest rate in February. They reflect the effect of the population density and the snow fall, etc.