Review and update to Code of Practice for controlling invasive non-native species

News Release

Immediate Release

08 October 2025

Environmental Standards Scotland calls for a review and update to the Code of Practice for controlling invasive non-native species like Japanese knotweed and giant hogweed

Today Environmental Standards Scotland (ESS) has called on the Scottish Government to commit to a review and update to the Code of Practice for invasive non-native species (INNS) in Scotland.

The Code of Practice for INNS, issued by Scottish Ministers under section 14C of the Wildlife and Countryside Act 1981, is an important reference point for land managers, public authorities and others with responsibilities for INNS management.

However, following a public Call for Evidence on the control and impact of INNS, ESS has concluded that the current Code of Practice is not fit for purpose, and an update of the code would improve the effectiveness of how INNS are managed.

INNS pose a serious threat to Scotland’s environment, economy and way of life. They are one of the leading causes of biodiversity loss globally, disrupting ecosystems, outcompeting native species and contributing to 60% of recorded global extinctions.

In a letter to the Cabinet Secretary for Climate Action and Energy, ESS has called for the Code of Practice to be updated to:

• clarify guidance on roles and responsibilities of public bodies and duty bearers
• ensure the accuracy of contact details of relevant bodies and duty bearers
• ensure legislative references are correct and up to date, setting out how they apply in Scotland
• ensure action is taken to strengthen public awareness of the roles and responsibilities around INNS management in Scotland

The term ‘duty bearers’ refers to organisations or other entities with specific roles in effectively managing INNS, such as landowners, who must prevent the spread of INNS through their land, and individuals, who have a responsibility not to plant invasive species or release invasive animals.

Scotland’s unique ecosystems, including its island habitats, are especially vulnerable to the pressures posed by INNS. A 2023 study conducted by the Scottish Government, identified 30 invasive non-native species with a high risk of arriving, establishing and impacting biodiversity in Scotland in the next decade.

Common INNS in Scotland include Reynoutria japonica and Heracleum mantegazzianum (more commonly known as Japanese knotweed and giant hogweed, respectively). These INNS can often be found along riverbanks and disturbed land, causing damage to native flora and infrastructure. Another example is the presence of stoats in Orkney, an invasive species first reported in 2010, that pose a significant threat to the islands’ native wildlife.

The direct costs incurred by the British economy due to the impact of INNS are estimated to be nearly £1.9 billion annually.

Mark Roberts, Chief Executive of ESS, said “INNS pose a threat to biodiversity, ecosystems and our economy. Once established INNS can be extremely costly and difficult to control.

“The Scottish Government has committed to addressing the challenges posed by INNS through various targets and initiatives. However, to do this we need a Code of Practice for INNS that is fit for purpose and will improve the implementation of the Wildlife and Countryside Act 1981, in Scotland. The Scottish Government should act on our recommendations and ensure that we are in a strong position to tackle INNS effectively in the future.”

ENDS

Notes to editors:

i) You can read ESS’ letter to the Cabinet Secretary here.

ii) ESS’ ongoing work on INNS

This recommendation builds on ESS’ wider analytical work on the control and impact of INNS. In 2024 ESS ran a public Call for Evidence to gather views on how legislation and policy are working in this area. In February 2025, we published a summary of responses, which highlighted that the Code of Practice is valuable but outdated.

ESS will continue to examine other issues raised through its Call for Evidence on INNS, including the effectiveness of prevention and control mechanisms such as Species Control Agreements and Orders. ESS will publish further findings in due course.

For media enquiries please contact:

Nicola McArthur

Smarts

ess@smarts.agency

07866 694 021

Christine Fergison

Smarts

ess@smarts.agency

07957 286 776

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