Are Human Activities Stressful for Wildlife? : Evaluation of the Physiological Stress in the Japanese Giant Flying Squirrel Inhabiting Mt. Takao

Abstract

　Many people visit Mt. Takao in Tokyo for recreation, such as climbing and wildlife viewing. These human activities may be stressful for the Japanese giant flying squirrel inhabiting Mt. Takao. Chronic stress negatively influences reproductive and immune system, leading to decline fitness. Therefore, it is essential to evaluate the stress of the human activities for an eco-friendly recreation. Here, we compared the physiological stress in Japanese giant flying squirrels using a fecal cortisol metabolites analysis between Mt. Takao and less human active area. In addition, because increase in human activities in holiday may cause the stronger stress levels in Mt. Takao, we tested whether fecal cortisol metabolites (FCM) levels increase due to Golden Week holiday. We found no significant difference of FCM levels between squirrels inhabiting Mt. Takao and less human area. Furthermore, although there was significant effect of holiday (before or after Golden Week holiday) on the FCM levels, no significant effect of interaction of area (Mt. Takao or less human area) and holiday. This result, therefore, did not support our hypothesis that the increase of human activities in holiday Mt. Takao causes stronger stress. Our results indicate that Japanese giant flying squirrels inhabiting Mt. Takao were not subjected to stronger stress due to human activities.