1. The present field research and behavioral study of Black Woodpecker (Dryocopus martius were carried out in the natural Fagus crenata forest from April to mid-December 1977. The study area is located at Mt. Moriyoshi, Akita Prefecture in northern Honshiu Japan, as shown in the previous report (Ogasawara 1977).
The field research of the trees used by Black Woodpecker were carried by four investigators during October and November 1977.
2. We observed five trees of Fagus crenata in Which Black woodpecker would nest in future. The several situations of these five nesting trees were similar to those of Hokkaido (Arisawa 1976).
3. We found that the six roosting trees of Fagus crenata, and that one of them was used by the female (No. 7 in Table 2), but it is not clear whether these five roosting trees, except No. 7, were used or not by Black Woodpeckers at present.
However, these roosting trees were in a very similar situation to those of Hokkaido (Arisawa 1976).
4. The situations of the nesting and roosting trees were very similar; namely, trees of Fagus crenata standing straightly on the ground, 0.5-1.0m in diameter at the breast height of tree, the nesting and roosting holes excavated at 8-12m in height above the ground, the undermost branches being above these holes, and the surface of the tree trunk being smooth. But the difference is that a nesting tree has one hole, whereas a roosting tree has usually more than one hole.
5.The dead and half-dead trees for feeding by Black Woodpecker were distributed widely. in the present study area within 300ha of our investigated forest. We recognized 471 dead trees of Fagus crenata (96.3%), three living trees of Fagus crenata (0.6%), eight dead trees of Pterocarves rhoifolta (1.6%), four living trees of Pteroearva rhoifolia (0.8%), and other three trees (0.6%), with feeding holes. It is very important that the density of these feeding trees is almost the same as that recognized in Hokkaido (1.6 per ha) as the investigation by Arisawa (1976) indicates.
6. The time when the female of this species went roosting, as in the present study from October to November, was almost 16:00. But it is very interesting that this female came into the roosting hole at 10:28 on 25th October 1977.
7. In Fagus crenata forest which is at its climax, one or two Black Woodpeckers (male and female) have fed gently or sometimes with loud sounds on dead trees, standing or lying on the ground.
8. We tried to show schematically how Black Woodpeckers use, for example, Fagus oreuata tree in a natural forest. We have many cases in which Black Woodpeckers used a big tree as a feeding tree as if it were partially dead.
In another case, woodpeckers have selected a favorable nesting tree on which they excavated a hole at a proper height, and used it a relatively long time, year after year.
If the nesting tree was older, woodperckers would used it as a feeding tree. Furthermore, we speculate that the nesting tree will be used as a roosting tree if the woodpecker excavates several holes, as shown in Fig. 8.