What is the relationship between water temperature and electrofishing effectiveness between 7° and 16°C?

The relationship between water temperature and electrofishing effectiveness in the range of 7° to 16°C indicates that both water and fish exhibit comparable conductivity within this temperature range. As water temperature increases, the conductivity of water generally rises due to higher ion activity, which aids in effective electrofishing.

When fish are metabolically active, they engage more with the electrical field created during electrofishing, enhancing the likelihood of capture. The fact that both water and fish become equally conductive means that the electrical field can efficiently interact with the fish. This makes electrofishing more effective since the fish can respond accurately to the field, leading to better results in capturing fish.

In contrast, the other choices do not reflect the physics of electrofishing effectively. For instance, while water being more conductive is a correct observation as temperature rises, it doesn’t address the comparative conductivity of fish. Similarly, the idea of current avoiding the fish or voltage gradients becoming steeper does not align with how fish respond to electrical fields. Therefore, the understanding of both mediums—water and fish—having similar conductive properties is critical for successful electrofishing practices at these temperatures.