Abstract
To increase catch efficiency, it is necessary to understand the habitat utilization of the target fish around fishing gear. A biotelemetry study using coded ultrasonic transmitters and set receivers was conducted to understand the habitat utilization of largemouth bass around a set net in Lake Biwa, Japan. Three receivers were installed on leader nets of the set net at short intervals by design to understand the fine scale movement of fish. Four fish were implanted with a coded ultrasonic transmitter and released near the set net. Two fish were monitored for over 50 days and showed diurnal habits. Just before the fish left the set net. the main current direction was southwestward and the current velocity was over 5m/sec. In a set net fishery, current profile is an important factor affecting the concentration and dispersion of the target fish.
