A cabled acoustic telemetry system for detecting and tracking juvenile salmon.

Abstract

The juvenile salmon acoustic telemetry system (JSATS) is a nonproprietary technology developed by the U.S. Army Corps of Engineers, Portland District for detecting and tracking small fish. The JSATS consists of acoustic microtransmitters; autonomous, cabled, or portable receivers with hydrophones; and data management and processing applications. Each microtransmitter, surgically implanted in fish, transmits a unique 31‐bit binary code encoded using BPSK at 416.7 kHz. Cabled systems are deployed at dams and used to determine passage‐route and near‐dam behavior for fish. Each cabled system is synchronized to a universal GPS clock and waveforms are saved to the computer before being decoded. Valid detections are separated from spurious detections using filtering processes requiring a minimum of six messages with a pulse interval matching that expected from properly functioning tags within a fixed period. Time‐of‐arrival information for valid detections on four hydrophones is used to solve for the 3‐D positio...