Electrofishing uses a small electric current to temporarily stun fish so they can be caught. This allows us to gather a sample from the stream to record the species and size of fish present. This gives us accurate information to analyse the health of the river.
When conducted by trained individuals, the fish do not experience any physical harm and are returned to the river.
Electrofishing helps us to identify locations where fish numbers are below expected, so where a fish pass or habitat improvement work will be most beneficial.
Assessment of fish populations is also the best way to test how successful work to improve habitat, such as a fish pass or removing a weir, has been. If it is not performing as well as expected, we can make changes and learn lessons for future work elsewhere.
We train volunteers to monitor water quality by kick sampling on a monthly basis. A kick sample involves collecting a sample of invertebrates with a net. We put them into a sampling tray and use an ID guide to record the different types. This gives an indication of the health of the river, for example a high number of true mayfly is a sign of a healthy river.