中海におけるアカエイを用いたバイオテレメトリの基礎実験

We observed swimming behaviour of the target fish(Dasyatis akajei) using a miniature acousitic pinger and an acoustic animal position detection system(AAPDS) based on SSBL(Super Short Base-Line) system in Lake Nakaumi. The pinger is attached to the head of the target and AAPDS is installed in a ship. The pinger generates a sound wave of 20kHz in every six seconds. The AAPDS measures range and direction of sound. The position(X, Y) of the target on the earth is decided by the data ofthe range and direction between the target and the ship, and ship position and heading. The depth(Z) of the target is obtained by a depth gauge installed in the pinger. In this experiment, we observed that the target swam in about 2.3 km/h(max.) and in through the middle depths of water.