Tagged fish yield migration data

Roach released in to the river were caught by anglers by rod and line

An experiment is under way to track the movement of 200 electronically-tagged roach which were transferred from a lake into the River Wensum in Norfolk.

Little information exists of movements of coarse fish after restocking.

The Environment Agency and Norfolk Fly Fishers Club, backing the experiment, believe these fish may have escaped into the lake when the river flooded.

They have now been released in fast- flowing water and it is anticipated they may migrate to sheltered areas.

All 200 fish were caught by the anglers using a rod and line.

Boost stock

Before they were released, they were implanted with a transponder tag to enable them to be tracked and monitored.

Equipment placed at strategic locations along the river will track the tagged fish over the next year.

Helen Beardsley from the Environment Agency said: "We hope the addition of the roach into the river will help boost the resident brood stock.

"They're being stocked in a fast-flowing stretch and not a typical deep or slow roach environment.

"We hope that they remain in the same stretch but due to the fast-flows we think that they may drift downstream seeking areas of refuge.

"Tagging the fish will therefore enable us to monitor their movements and obtain never before achieved information."