We surveyed the utilization of nest boxes by birds and small mammals in a windbreak forest in Tokachi, Hokkaido. We set up 40 boxes at two test sites with different types of trees : Site A had 71-year-old oaks (Quercus dentata) and Site B had 45-year-old white birches (Betula papyrifera). We put 20 boxes at each test site : 10 in the trees along the outer edge of the strip-shaped site and 10 in the trees along the inner edge of the site. The test was conducted from May to October 2006. Four bird species (Passer rutilans, Parus ater, Parus major and Dendrocopos major) and two mammals (Pteromys volans orii and Plecotus auritus) used the boxes mostly from May to June, in the breeding season. Dendrocopos major used the boxes as a roost throughout the test period, with the most frequent use in July. The mammals used the boxes only during the daytime, as dens. There was increased use in August by P. volans orii and use in September and October by Plecotusan auritus. Parus ater and P. major, which used only the boxes at Site A, while P. rutilans mostly used the boxes at site B that were not used by P. ater and P. major. Pteromys volans orii used the boxes at Site A more often than those at Site B.

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We observed the food items consumed by the Siberian flying squirrel, Pteromys volans orii, in Obihiro, Hokkaido. We recorded thirteen tree species that nineteen radio-tagged flying squirrels foraged from September 1991 to August 1993 and from May 2005 to August 2006. The number of tree species foraged by flying squirrels differed according to the vegetation of the sites. Flying squirrels foraged leaves, buds, catkins, seeds, infructescences, acorns and fruits from both broadleaf trees and conifers. Leaves, buds and seeds appear to be the main food items for the Siberian flying squirrel, since they consumed these items over a long period. The flying squirrels frequently fed on leaves from May to July, when they had low fiber and a high nutritive value, but ate more fibrous mature leaves in late autumn due to the low availability of their preferred items. Flying squirrels also foraged more pine tree seeds in early autumn, suggesting a strategy for increasing their weight for survival over the winter. The pollen and acorns used by flying squirrels may be related to their reproductive cycle, due to the high nutritive value of these items. One of prerequisites for conservation of the Siberian flying squirrel is that their food trees and items are investigated at different sites.

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We surveyed the habitat utilization of the Japanese hare (Lepus brachyrus) during the winter season, including habitats composed of mosaic-like distributions of mixed forest, bamboo thickets, orchards, wastelands, farmlands, and paddy fields. In the analysis, Quantification (I) method is used as items geographical feature, canopy, vegetation coverage and landscape, and as outsiders, the number of droppings and feeding signs. As for the score of droppings vegetation item has more than other items, considering it is an important role to select the habitat. That is followed by canopy items. Among vegetation items the orchard has always more than other vegetation types, indicating the hares stay for the long term there. Regarding the feeding signs, though they differed by month, the scores for paddy fields, wastelands and orchards were highest. That is because the hares had a preference for new buds after the harvesting of the paddy fields or buds of weeds in the orchards and wastelands. Japanese hares generally consume Sasa grass which is concentrated in mixed woodlands, considered to be one of their feeding grounds. Droppings were found to be concentrated in the orchards, where the thick weeds provide useful cover for the hares. These orchards seem to be used as transit sites, which the hares use to move to and from other favored feeding sites.

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The Japanese squirrel (Sciurus lis) selectively uses red pine forests as their habitat. The vegetation structures and squirrel abundance were compared among red pine woods with pine wilt disease (at Tsuru City) and without it (at Fiji-Kawaguchiko Town). At the Tsuru study site, the feeding remains by squirrels increased with the percentage of live pine trees. At all study sites, the number of middle layers affected the abundance of feeding remains.

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Ground beetles (Carabidae and Brachinidae) were collected with pitfall traps at nine plots in various types of forests in and around the Akanuma Experimental Station of the Forestry and Forest Products Research Institute, in Hatoyama Town, Saitama Prefecture from April to December in 2002. A total of 573 individuals belonging to 36 species were collected, indicating that the ground beetle fauna in the study area was rather rich. Cluster analysis based on Pianka's α, as an index of similarity in composition between the ground beetle assemblages, indicated two clusters, i.e., a cluster of four plots where the undergrowth was rather poor and a cluster of two plots where bamboo grass was densely growing on the forest floor. The other three plots did not show similarity to any other plots. Species of the genus Synuchus predominated and the species composition was rather simple at the four plots with poor undergrowth. More diverse ground beetle assemblages were found at the other five plots, including two with thick undergrowth of bamboo grass and the three with rather weedy undergrowth. No clear effect of upper layer tree species on the composition of ground beetle assemblages was detected.

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Mandarin Duck Aix galericulata populations were censused along one to three 2-km transects in 809 quadrats (5×5 km) in Hokkaido from early May to late July, 1976-2007. In addition, observation records were obtained from the literature and personal communication with local ornithologists. Combining these observation records, the total number of quadrats censused was 1,258. Mandarin Ducks occurred in 44 quadrats (occurrence frequency 17.8%) in plains, in 103 quadrats (22.5%) in intermediate areas including both plain and mountainous areas in a quadrat and 98 quadrats (18.0%) in mountainous areas. The altitude of the highest site where Mandarin Ducks were observed was 820 m above sea level. Mandarin Ducks occurred in lower and middle reaches of rivers, lakes and reservoirs in mountainous areas in May, and in middle and upper reaches of rivers and lakes and reservoirs in mountainous areas in June and July. Mandarin Ducks prefer mainly waters surrounded by forests as habitats during the breeding season.

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The age distribution vector of one population at a time projects for each one to the next time through the Leslie matrix for these components, the survival rate and fertility rates are arranged in order. This report addresses only the survival rate as an effect of population in simulation through Leslie matrices with two systems of high and low rate survival rates, in the same fertility rate. We discuss on the differences between the age distribution vectors by simulating the two systems, that is, in the high rate system survival rates are 0.6 and 0.9, and in the low system 0.5 and 0.6 in both of the early stages (0 month age and 1 month age) of life table, and 0.9 in the middle stage, 0.5 in the terminal stage in both systems. The results show that in the high rate system the populations reach easily over 100/ha, while in the low rate system the populations fluctuate between low population levels, never reach to 100/ha.

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To learn about bird communities in the Renkouji Experimental Forest, an isolated forest in the Tama Hills, we set out mist nets every month from November 2006 to October 2007. A total of 23 species and 222 individuals were captured during the study period. The number of captured individuals was higher at the forest edge than inside the forests. Both the number of species and individuals decreased after under layers, such as Aucuba japonica and Pleioblastus chino, were cut.

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