Laboratory Investigations on the Use of Strobe Lights and Bubble Curtains to Deter Dam Escapes of Age-0 Muskellunge

The movement of Muskellunge Esox masquinongy over a dam to leave a reservoir is known as dam escape. It is common in Midwestern U. S. reservoirs and has been as high as 25% of the adult population. A variety of barrier and guidance systems have been used to control fish movement, but the success of such barriers has been mixed and appears to be very species dependent. We examined the effectiveness of a simple, relatively low-power and low-cost bubble curtain, strobe light, and bubble curtain with strobe light barriers to deter Muskellunge from escaping over spillways. In 15 replicate trials of each treatment type conducted in a simulated spillway, age-0 Muskellunge were more likely to escape during daytime trials (P < 0.01), but the three barrier combinations did not reduce rates of escape. Light and bubble curtain barriers will likely not be effective in reducing spillway escapes by Muskellunge.