Experimental set-up for small fish. Picture by Dr. Jan Dean
Lab or tank experiments on fish have been around for decades, beginning with studies of fish behavior in electric fields. Presently, tank experiments are used for evaluating the effectiveness of candidate waveforms, estimating thresholds for various reactions that assist capture, guidance, and electrosedation, and determining probability of trauma. While insights gained by lab work, in combination with field trials, can and have improved fisheries sampling and provided insights for risk analysis, there are pitfalls that can sink the ship. A couple problems that often occur are the rationale for setting dose levels and the actual description of dose levels. These issues can lead to misinterpretations, inappropriate management decisions, and constrain application of experimental results. In fact, dose setting is becoming a big issue in electrofishing experimentation. I have seen studies lately that have used incredibly high doses, in fact extreme overdoses, preventing a connection from the lab to application in the field. I think the results of those studies are relatively meaningless. And, most of the disconnect is due to a poor understanding of electric fields generated by common sampling gears and typical exposure times while electrofishing.