Abstract
1. The ecological separation of sympatric Paridae in central Japan is analyzed by the comparisons of feeding sites and foods for five species: Aegithalos caudatus, Parus major, P. ater, P. montanus and P. varius.
2. The ecological separation in Paridae is more conspicuous in the winter than summer.
3. The striking co-existence in the broad-leaved deciduous trees and planted larch was found between Ae. caudatus and P. major. These two species divide the upper and lower strata, the external and internal parts, and the twigs and the branches to trunk in trees.
4. In the canopy, the co-existence of Ae. caudatus and P. ater is remarkable. Each two species prefers different tree species, and different positions in the branches. Moreover, in the larch, the status of Ae. caudatus is stable while P. ater is unstable. This becomes more apparent at critical periods when the twigs are covered with snow or ice.
5. In the evergreen forest of south-western Japan, the co-existence of P. major and P. varius is remarkable. These two species divide the upper and lower strata in the forest. The status of P. varius in the trees is equivalent to P. caeruleus in Europe.
6. In sub-alpine zone, the separation between P. ater and P. montanus in the mixed forest is for the tree species. The former prefers the coniferous trees and is a migrant influenced by the production of resources. The latter prefers the lower strata and the dead branches, and is resident.
7. The foods of Ae. caudatus differ from the genus Parus which feeds on the coniferous seeds in autumn to winter. Each species of Parus has diets different in size and items.
8. P. ater, P. montanus and P. varius have food storing behavior while the other two species have not. In the sub-alpine zone, the storing sites and foods of P. ater differ from that of P. montanus. Moreover, the biological significance of the storing behaviors of both species varies. In P. ater which is locally migratory the habit is correlated with the storing of food when the local production is at its hight, while in resident P. montanus the habit is advantageous for securing constant food supply. In addition to these, P. montanus conceals the seeds of various harbs and the colored berries.
9. The ecological separation of Paridae is sharp and complex in the forest canopy but at lower strata it is simple being used only by few species.
