Sensor Fish (IMAGE) DOE/Pacific Northwest National Laboratory Caption PNNL's Sensor Fish is a small tubular device filled with sensors that analyze the physical stresses fish experience as they pass through dams and other hydropower structures. Credit Pacific Northwest National Laboratory Usage Restrictions Credit PNNL License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.