Abstract
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.
