Burger, Carl V.Murphy, AaronCarstensen, LeeO’Farrell, MartinParkin, John W.2024-04-262024-04-262013-06-27https://hdl.handle.net/20.500.14394/24670<p>Carl Burger has led the Science Department at Smith-Root, Inc. (Vancouver, WA) since 2007. He coordinates research and R&D trials, and helps conceptualize technology for fish and marine mammal behavioral guidance. He spent a previous 31-year career with the USFWS ... in venues that included a Pacific salmon research scientist (Alaska), a science center director (Washington State), and a recovery plan administrator for listed Atlantic salmon in Maine. He served as President of the American Fisheries Society from 2000-2001. His presentation today will focus on the use of graduated-field electric barriers to safely influence the behavior of downstream-moving fish at several example locations in the U.S.</p>Safe, effective downstream fish passage has been a high priority for both hydropower and fisheries managers for several decades. Many technologies have been evaluated. These include physical structures (such as inclined planes and screens), sound (in various forms), lights, and other techniques (e.g. bubble barriers) in attempts to guide downstream-moving fish away from irrigation and hydropower-related water intake canals. This paper focuses on the use of mild, electric gradients (innovative applications of pulsed DC) to control downstream fish behavior and movements. While most deployments of Graduated-Field Fish Barriers (GFFBs) have been used for upstream deterrence, several evaluations have been conducted on attempts to direct downstream-moving fish, where approach velocities have not exceeded about 0.5 m sec-1. Three examples are highlighted. The first involves a GFFB installation to reduce juvenile salmon entrainment into an irrigation canal on the Sacramento River, CA. Despite poor barrier siting and river flows directed toward the intake, entrainment of downstream-moving, juvenile Chinook salmon was reduced by up to 79%. The second example is a recently installed downstream barrier to keep adult salmonids from entering the Gunnison Tunnel, an irrigation diversion near Montrose, CO (that will soon address hydropower needs.) The third example involves controlled, laboratory-raceway trials on the “transformer” life stage of invasive sea lamprey at the USGS Hammond Bay Biological Station in Michigan. Preliminary data show that very low voltage, graduated fields of pulsed DC successfully guided 55-74% of the downstream-migrating sea lamprey transformers into a mock trap at the downstream end of the raceway (at four different water velocities). An innovative, hybrid-design concept is proposed for future downstream guidance of fish. The concept involves graduated, pulsed-DC electric fields in concert with low-frequency acoustics (using pulse-pressure, seismic water-gun technology to elicit a fright response and move fish around water intakes upstream of GFFB arrays). This combination of approaches may be key to achieving high levels of success in future downstream fish guidance applications. Once fully tested, this tandem approach may be a useful tool for managers who desire novel ways to enhance downstream fish passage outcomes.event