Hydrocotyle ranunculoides was first recorded as being naturalised in the UK in Essex in 1990 and has since been found across England, Wales and Northern Ireland. The weed clogs up slow-moving water bodies, hampering access for recreational activities, such as fishing, and reduces the aesthetic appeal of landscapes, with knock on effects to tourism. It also negatively impacts on water flow, sedimentation, and light and oxygen levels, and endangers communities of native plant species and associated fauna. The weevil Listronotus elongatus has shown promise as a biological control agent of H. ranunculoides. The Centre of Agriculture and Bioscience International (CABI) produced a risk assessment of the weevil for release in England, which was reviewed by Defra and externally by the Advisory Committee on Releases to the Environment and other bodies.
A stakeholder/public consultation subsequently took place between March and May 2021, and a summary of responses to questions raised in the consultation can be found here.