What is pulsed direct current (DC) in relation to electrofishing?

Pulsed direct current (DC) is particularly effective for capturing fish during electrofishing because it allows for controlled stimulation of the fish's nervous system without causing significant harm. The pulsed nature of the current means that it can create a series of short bursts rather than a continuous flow, which effectively attracts and immobilizes fish temporarily. This method is preferred as it can be tailored to various species and environmental conditions, maximizing the efficiency of capture while minimizing stress and injury to the fish.

In contrast, options relating to high voltage or methods for increasing fish size do not align with the principle or purpose of pulsed DC in electrofishing, which focuses solely on the capture and study of fish populations. Similarly, mechanical fishing does not pertain to the principles of electrical techniques used in electrofishing.