Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, what recent steps his Department has taken to control the prevalence of (a) floating pennywort, (b) Himalayan balsam, (c) signal crayfish, (d) Japanese knotweed and (e) American mink.

The Government recognises the threats posed by invasive species and has a comprehensive Great Britain Non-native Species Strategy designed to co-ordinate action to tackle these threats.

Floating pennywort, Himalayan balsam and signal crayfish are listed as a ‘Species of Special Concern’ under the Invasive Alien Species (Enforcement and Permitting) Order 2019, which means that they cannot be brought into GB, kept, bred, transported, sold, used or exchanged, allowed to reproduce, grown or cultivated, or released into the environment. This legislation is aimed at preventing further introduction and spread of these species.

Japanese knotweed and American mink are listed on Schedule 9 of the Wildlife and Countryside Act 1981. This makes it an offence to allow American mink to escape into the wild, and to cause Japanese knotweed to grow in the wild.

Floating pennywort, Himalayan balsam and Japanese knotweed control.

In partnership with the Welsh Government and Natural England, Defra is funding specialist scientists at the Centre for Agriculture and Bioscience International (CABI), an inter-governmental, not-for-profit organisation, to conduct biological control (biocontrol) research into the use of naturally occurring, living organisms to tackle floating pennywort, Himalayan balsam and Japanese knotweed. Biocontrol could provide a more cost- and time-effective way of managing these invasive plants as compared to manual removal.

Before any release of biocontrol agents, experts at CABI conduct extensive research and safety testing to ensure that native species will not be targeted, and then obtain formal approval to release them. This research is in its early stages, and releases at trial sites are ongoing for a weevil from Argentina, Listronotus elongatus, that targets floating pennywort; a psyllid from Japan, Aphalari itadori (a sap-sucking insect), that targets Japanese Knotweed; and a rust fungus that targets Himalayan balsam. Information about the research can be found on the CABI website and additional information can be found on the Japanese Knotweed Alliance website.

Defra is also part of a national partnership formed between government and non-government organisations that developed the Great Britain Floating Pennywort Strategy to manage this invasive plant.

Additionally, the Government run awareness raising campaigns such as ‘Be Plant Wise’ and Invasive Species Week. These campaigns provide species information and online training materials on biosecurity for industry and the general public. The Government has also developed guidance on how to prevent the spread of invasive non-native plants, and how to treat and dispose of them, which can be found on GOV.UK:

How to stop invasive non-native plants from spreading - GOV.UK (www.gov.uk)

Signal crayfish

To support on-going management of large and damaging populations of signal crayfish in a feasible, effective and economically viable way Defra has put in place management measures for this widely spread species with containment and exclusion zones for signal crayfish. This approach prevents spread through restricting and controlling the commercial use of the species and preventing the live movement of the species entirely. This is aimed at preventing its continued spread into uninfected waterbodies in England.

American mink

Natural England are funding 5 partner-led projects (2023-25) which will be controlling mink to benefit water vole populations through the Species Recovery Grant Scheme. The total value of these projects is £479k and include projects to build on the work carried out in East Anglia to develop a mink free area stretching from Lincolnshire to the Thames

In the last financial year for which there is data, 2022/23, the Environment Agency spent £136,800 on 8 projects that controlled mink. The Environment Agency’s partners (including local authorities, Natural England, water companies and eNGO’s) contributed an extra £126,900 to those projects.

Local Action Group funding

Local Action Groups, with support from government, play an invaluable role in actively reducing and eradicating invasive non-native species.  Defra is currently funding twelve Local Action Groups (LAGs) across all regions in England to control invasive species through its Local Invasive Species Management Fund. The two-year fund totalling just over £300,000 is being used by LAGs mostly to remove invasive plants including floating pennywort, Himalayan balsam and Japanese knotweed. A small number of LAGs are conducting mink trapping and signal crayfish control. Most of these projects also involve training volunteers, awareness-raising and community engagement.