Although bears depend on berries as a food resource in early summer, little information is available about the distribution of berries as food resources for bears. Therefore, the abundance of Japanese mulberry, an important food that bears frequently take in early summer, was investigated to elucidate the distribution of bear food in early summer. First, because Japanese mulberry is an intolerant tree, we compared the number of Japanese mulberry trees along forest roads using line-transect method. Results showed that numerous Japanese mulberry trees are distributed along forest roads, and that the areas with most frequent distribution are between forest roads and creeks. The results were affected by the degree of canopy density and the amount of moisture in soil. We investigated the existence of scars made by bears on Japanese mulberry trees by size. Scars on Japanese mulberry trees were found most frequently on trees of 11-20 cm DBH. Bears might prefer trees of this thickness. Additionally, we frequently observed bear scars at places that were not facing forest road lines. Future studies must clarify why most scars were made at 11-20 cm of DBH and show why bears use Japanese mulberry trees distributed in areas that are not facing forest roads.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract