Sensor fish are artificial devices containing microsensor transducers to measure the three types of forces (tensile force, compression, and shear strain) a fish may experience during passage. Sensor fish approximate the size and shape of actual fish, and were originally designed as a smolt-sized salmonid surrogate (Figure 14). When released through a passage route and then recovered downstream, sensor fish can provide information on the types of conditions and mechanism that result in various types of injuries.
4.3.5.1 Advantages and disadvantages of approach
Use of the sensor fish devise to assess entrainment effects has advantages and disadvantages relative to the other approaches evaluated, as discussed below:
Advantages
- This method is able to provide substantial information on the source of injury, which can be used to make recommendations on project improvements for passage efficiency.
- Live fish do not have to be used.
- Sensor fish can easily be retrieved by attaching microtransmitters or balloon tags.
- Assessment of multiple passage routes and project operations is possible.
Disadvantages
- Currently sensor devices are too large to be placed inside live fish, and the artificial sensor fish does not simulate behavior of live fish.
4.3.5.2 Site-specific considerations and applicability
Many of the advantages and disadvantages of this approach will depend on site-specific considerations, as discussed below:
- This approach is best used when entrainment and mortality rates are either known or not relevant. The sensor fish can determine appropriate measures for modifying project facilities to lower impacts, but does not determine the rate of those impacts.
- Has been applied at numerous dams on the Columbia River; at the Lower Granite Hydroelectric Project and at the Ice Harbor Hydroelectric Project (both owned by the USACE, Walla Walla District) on the Snake River, Washington; and at the Prosser Irrigation District Dam on the Yakima River, Washington.
4.3.5.3 Selected references
Janowski, P. 2000. Running the dam gauntlet: in the name of science, a rubber fish serves as stunt double. Scientific American March: 18.
Carlson, T. J., J. P. Duncan, and T. L. Gilbride. 2003. The sensor fish: measuring fish passage in severe hydraulic conditions. Hydro Review 22 (6): 62-69.
Carlson, T. J., and J. P. Duncan. 2004. Characterization of spillway passage conditions at Ice Harbor Dam, Snake River, Washington, 2003. Draft final report PNWD-3462. Prepared by Battelle, Pacific Northwest Division, Richland, Washington for U. S. Army Corps of Engineers, Walla Walla, Washington.
Johnson, R. L., B. G. Gray, S. L. Blanton, J. P. Duncan, R. W. Gilbert, G. A. Anderson, and D. A. Neitzel. 1998. Advanced Sensor Tag for Improved Turbine Design. Pacific Northwest National Laboratory, Internal Report, Richland Washington.
