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The bio-logging technique is extensively used in the fields of ecology and ethology, wherein a data logger, such as a sensor or camera, is attached to the target animal’s body to collect the required data. In this method, the efficiency of recovery of the data logger is not ideal. In this study, we proposed a new recovery method, with the aim of addressing the aforementioned problem in bio-logging. The authors previously fabricated a data-logger separator, which weighed approximately 10 g, and was targeted at small seabirds. Because there were some problems associated with the circuit board and the separation performance of this device, we modified the device to overcome the previous drawbacks. We fabricated a flexible printed circuit to improve the operation of the mounted actuator and wireless microcomputer, and improve the efficiency of the fabrication process. We conducted an experiment to determine the proper length and position at which the actuator is attached, in order to achieve a stable motion. We thus fabricated a new prototype with these improvements and performed an operational test at low temperatures from a particular distance, simulating actual usage in a natural environment. The results demonstrated that separation occurred without failure, thus indicating that the separator can be efficiently used in practical environment.

The biologging approach of attaching a logger to the body of an animal provides information that cannot be obtained by conventional direct visual observation. Marine zoologists have used this technique for observing sperm whales preying on giant squids in the deep sea. However, it is almost impossible to capture a sperm whale to attach a logger, because of its large size. Therefore, researchers have used a long pole to attach a logger from a ship to the back of sperm whales. Unfortunately, this method is risky and requires a skilled team. In this paper, we propose a logger attaching system using a drone to solve this problem. The proposed method can be trained on land; thus, it is relatively easy to train a team, and the mobility of the drone can shorten the installation time. Several pieces of equipment developed for the proposed method are described in detail. Furthermore, field experiments were performed with sperm whales to confirm the feasibility of the system. A suction cup of the seventh prototype of the whale rover was adsorbed onto the back of a sperm whale. Although a complete installation was not possible, it was demonstrated that operation was possible in a short time using the proposed method.

In ecology and ethology, a technique called ‘bio-logging’ has been used to record the behaviour of wild animals by attaching a small logger, which includes a global positioning system (GPS) or acce...