2010 年 12 巻 2 号 p. 11-18
Our objectives were to produce a damage risk map (hazard map) to support countermeasures against damage to orchard fields caused by Japanese black bears (Ursus thibetanus japonicus) and to formulate conservation management plans. We investigated orchard fields at 116 sites in Shiwa Town, Iwate Prefecture, Japan, assessing whether the or chards had been damaged by bears and recording the orchard's environmental conditions. Furthermore, we analyzed the relationship between the damage and the environmental conditions in orchard fields using a classification tree model. We classified damage risk into the following three categories: (1) high risk of damage occurring in orchard fields in remote mountain areas with adjacent forests having an adjacency rate of greater than 53%; (2) moderate risk of damage occurring in orchard fields in remote mountain areas with adjacent forests having adjacency rates of 53% or less; and (3) low risk of damage occurring in orchard fields with no adjacent forest or where the forest is divided into smaller parts. To verify whether the model we used was appropriate, we validated the model. We confirmed that it is possible to generate a hazard map for orchards based on the environmental conditions of the orchard fields.