Crop damage by wild animals become a serious problem in Japan. Monitoring wild animals is important to understand the circumstance and find appropriate solutions. We have proposed to introduce multiple mobile robots into a monitoring system as a novel ecosystem management method. This method is expected as a safe and efficient observation method compared to conventional methods such as hand-carried sensor and monitoring post. The most challenging task is to have a high locomotion performance of the robot so that the robot cope with complex environment such as forest area where a lot of obstacles and uneven terrain are existing. The objective of our work is to design a platform of mobile robot that can move on rough terrain and improve locomotion performance of the robot so as to move autonomously. We have developed a tiny mobile robot named WAMOT that have high locomotion performance in forest area. We have been engaged in improving the locomotion performance of robots by proposing novel locomotion mechanisms and locomotion algorithms. In this presentation, we are introducing our concept of ecosystem management using mobile robot and reporting the developmental status and some experimental results of operating robot.