The featured image is an electrical field intensity map for a Missouri Department of Conservation stream electrofishing boat. The boat is depicted as the white area; the two anode array fields are shown in red. Many thanks to Andy Turner of MDC for providing this graphic.
In electrofishing classes, Alan Temple often uses the term electrical net when discussing standardizing by power. The analogy is that a gill net, for example, can be of a fixed size – length, height, bar mesh – and construction and can be deployed the same way for standardized fishing. When we standardize by power in electrofishing, the objective is to produce the same size effective fishing zone for any water conductivity. That requires adjustments to the applied voltage, current and power in waters of different conductivity so that the same electrical power density in the water enters the fish and causes the desired fish capture response. But how large is the electrical net? This blog presents a method of calculating the size of the electrical net based on hypothetical but realistic values for a typical two-boom electrofishing boat with the boat hull as the cathode and with either Wisconsin rings or spider arrays for the anodes. Be aware; there will be formulas and calculations. Hang on, I think it will be worth it.