Currently, where herring go after spawning in Prince William Sound (PWS) remains a mystery. Researchers are using acoustic telemetry to track fish movements so we can learn where they go throughout the year. This project tests the utility of acoustic tags for tracking the movements of adult herring; specifically, if and when adult herring migrate out of and back into the Sound.
Adult herring are captured using jigs and transferred to a seawater aquarium. The herring are sedated, measured and a small acoustic tag surgically is implanted. The tags transmit an underwater sound that can be “heard” by portable hydrophones and groups of acoustic receivers installed in the Sound which “listen” for tagged fish. These receivers are placed near the spawning grounds and at the major entrances to Prince William Sound.
The ability to track herring is critical to answer questions about herring movement patterns between feeding and spawning sites. Knowing where the fish are, we can improve the design of studies that examine factors such as predation, food availability and stock genetics that affect herring populations.