Development of a Device for Recording Power Output for Electrofishing Standardization

Standardization of boat electrofishing is required for consistency in fish population assessments and for comparisons of data across time and space. Power-based selection of boat electrofisher output to maintain constant levels of power (W, voltage times current) for transfer from water to fish, over a range of water conductivities, is a primary aspect in the standardization of boat electrofishing. Tables of output power goals for ranges of water conductivity, for typical boat electrofishing operations have been developed and published. However, widespread standardization of power output of boat electrofishing control units has been hindered by limitations in the metering of voltage and current. Some control units have metering for voltage or current, but not both and some provide average output while others provide peak output. In response to this deficiency, a device was developed to provide biologists the means to measure various properties of electrofisher output [e.g., peak, root-mean-square (RMS), and average measures of voltage (V) and current (A), pulse-frequency (Hz), and pulse-duration (ms)]. The device plugs directly into the electrofishing system (between the control unit and the electrodes) to allow simultaneous measurement on a standard laptop computer. Tests of the device conducted on a 2.5 Generator Powered Pulsator (GPP) electrofishing unit showed accurate measurements of voltage, current, pulse-duration, and power over a wide Percent of Range (PR 10 – 100%): V_peak 169 – 445; V_RMS 80 – 275; V_average 67 – 234; A_peak 2.0 – 6.6; W_peak 370 – 2500; W_RMS 83 – 981; W_average 58 – 710; pulse duration 2.3 – 6.8 ms). The measurements were input into the software application to match the output of the electrofishing system to established power goals. Additional bench-top and field testing of the device and this approach to standardization of electrofishing output power on other systems are underway.