Monitoring Movements of Juvenile Anadromous Fish by Radiotelemetry

Abstract

We developed miniature radiotelemetry tags to monitor the movement of smolts of Atlantic salmon (Salmo salar) and young-of-the-year rainbow trout (Salmo gairdneri) and American shad (Alosa sapidissima). Transmitter modules (30-MHz, 1.5 x 0.9 cm) were inserted in the stomachs of the salmonids and attached externally to American shad. Signal range averaged 0.6 km in water depths to 45 m. Normal transmitting life was 1 week with a 0.5-g battery.