Use of a Sweeping Low Frequency Pulsed DC Electrical Field to Control Bighead and Silver Carp

The goal of this research was to evaluate the efficacy of various electric field settings to direct bighead (Hypophthalmichthys nobilis) and silver (Hypophthalmichthys molitrix) carp movement. Behavioral responses of varying sizes of bighead (4 – 100 cm) and silver (mean TL 16 cm) carp were recorded for a low voltage, low frequency pulsed DC sweeping field. The effectiveness of the sweeping field was characterized by the ability the number of sweeps required to move all four size classes of fish into a predefined area. Traditional graduated field fish barriers immobilize fish as they swim upstream through the field and subsequently returned downstream from the barrier via flow. In low to no-flow environments such as a lock chamber, however, there exists no flow capable of returning fish downstream of the barrier. The implications of these findings for fisheries management goals related to Asian carp and other species will also be discussed.