Contrary to the more common way of fishing ‘hook, line, sinker’, there is electro-fishing! Electro-fishing is a method used for scientific surveys of fish populations. Using direct current electricity you can create an electric field that stuns nearby fish. This makes it incredibly easy to net them. Once they’re netted you store them in the live well while you continue your survey, in which time they usually start to come back to normal.
When you’re finished collecting fish in your survey area then you can start to identify them. You keep track of the different types of species found and how many. Depending on the fish size, they may also be weighed and measured.
Knowing what types of fish are there and in what abundance really helps to inform you on water quality. Fish that are more reliant on clean water and are pollutant sensitive are a good sign. While having a profound amount of pollutant tolerant fish might mean higher pollution in the water.
These waterways are vital to the ecosystem, as are the fish that live in it, so these surveys really help to give us a good idea of the good and bad changes that’re happening in that environment.