The anglers clearing a Torfaen canal of duck weed

"The canal is so full of duck weed, it is stopping the sunlight penetrating the water and the fish are struggling," says Kevin Putnam, a member of the Valley Carpers.

An estimated quarter of a tonne of weed has been cleared by the group in just two evenings at Pontnewydd.

They said Torfaen council is not dealing quickly enough to clear waterways around Cwmbran that are swamped in weeds.

Torfaen council said it had been in talks to arrange a meeting "at the earliest opportunity".