A session showing locals how to evaluate river health was arranged by the Wye and Usk Foundation together with the Freshwater Habitats Trust.

The event sought to teach attendees how to identify different types of stream-dwelling creatures.

These animals, such as caddis flies and stone flies, reveal the condition of water ecosystems and provide an important food source for fish.

Recording various invertebrate species allows volunteers to supply data that shapes protection work and restoration schemes.

A spokesperson said that giving volunteers the ability to find and record these species provides the organisations with extra details to inform their conservation work and restoration projects.