An army of 2mm long weevils have been introduced into the Llantarnam section of the Monmouthshire and Brecon Canal to help battle the rapid growth of water fern.
Water fern (Azolla filliculoides) can be problematic if left in a canal network because of its quick growth. It can cover a large area of a canal in a matter of weeks which reduces light and oxygen levels within the water killing fish and other wildlife.
It was introduced into the UK in the 1800s as an ornamental plant and is now one of the UK’s most invasive species. The weevils are regarded as the greenest and most sustainable way to tackle the problem as they don’t cause any damage to humans, other animals or plant life.