Policy paper

Grey squirrel policy statement: managing the impact of grey squirrels

Published 29 January 2026

Applies to England

Introduction

The grey squirrel is a widely spread non-native invasive species. As well as being a threat to the native red squirrel, it poses a severe challenge to the sustainable management of woodlands in England.

Since their introduction to England in the late 19th century from North America, the grey squirrel population has increased to an estimated 2.7 million across Great Britain. The growth of the grey squirrel population has contributed significantly to the decline of the native red squirrel, which is now classed as endangered in this country.

Grey squirrels out-compete red squirrels for food as well as spreading the squirrel pox virus to them – a pathogen that is usually fatal to red squirrels, with greys rarely affected.

In England the red squirrel population is fragmented, now only occurring in isolated populations on the islands in Poole Harbour and the Isle of Wight and across the north of England. England’s population of red squirrels is estimated to be just 38,900. Monitoring of red squirrel populations in the north of England shows that effective management of grey squirrels has stopped the decline in the red squirrel range.

Grey squirrels also cause damage to woodlands by stripping bark from trees, which in extreme cases can lead to tree death. Surveying of one-hectare grid squares across England between 2010 and 2015, as part of the National Forest Inventory Survey, found squirrel damage was present at 16% of sites. The frequency of damage varied across England, with bark stripping damage most common in the south-west (32% of sites) and Yorkshire and the Humber (23% of sites).

The economic cost of damage from grey squirrels to our woodlands, not including costs to our biodiversity, is estimated at £37 million per annum in England and Wales. This comprises an estimated reduction in timber value and restocking costs (£13.7 million), loss of carbon value (£9.2 million) and current costs of grey squirrel control measures (£14.1 million).

New and existing woodlands are crucial to the government’s plans to meet net zero emissions by 2050. The government has therefore committed to increasing woodland and tree canopy cover of England to 16.5% by 2050. Damage from grey squirrels can act as a disincentive to the planting and management of trees and woodlands, particularly broadleaved trees. This in turn acts as a significant blocker to the growth of domestic timber supply chains. The threat of grey squirrel damage can also lead to landowners limiting species diversity in woodland planting, which further reduces woodland resilience.

This is why we are updating the 2014 Grey Squirrel Action Plan to tackle this economic and environmental threat, protecting our much-loved woodlands and vital rural economies. This updated grey squirrel policy statement sits alongside the England Red Squirrel Action Plan (ERSAP), led by the UK Squirrel Accord (UKSA), which aims to reverse the decline of the red squirrel in England, and the Great Britain Invasive Non-Native Species (INNS) strategy, which outlines action for INNS, including the grey squirrel.

The actions we will take over the next 5 years include:

• encouraging landowners to take greater action through financial incentives and advice
• backing our nation’s conservation volunteers and landowners, by leading communication on the impacts of grey squirrel and providing support for training in grey squirrel management
• supporting research into novel forms of population management

Defra and the Forestry Commission will play a leading role in delivering the ambitions set out in this statement. We will work in partnership with the forestry sector, landowners and managers, environmental charities, community and volunteer groups, and researchers to help us meet the challenge. We will act as a catalyst for the sector, providing funding and guidance to accelerate action.

Policy approach

In 2019 Defra carried out a consultation on 14 invasive alien species (IAS), which are widely spread in England and Wales, seeking views on proposed management measures. IAS are also known as invasive non-native species. The consultation included grey squirrels.

The government response to the consultation aims to work towards reducing the impact of these IAS on native biodiversity, ecosystem services and wider socio-economic impacts.

The management measure aims for grey squirrel, listed in the government response, are to:

• control the current population of this species, to reduce its further spread and to eradicate in the wild where possible using humane measures, where outcomes are achievable and benefits are sustainable
• prevent establishment on islands where the species cannot colonise naturally
• prevent establishment in areas that are the preserve of red squirrel populations
• reduce the number of individuals in captivity over time

The actions set out below are in support of the first 3 aims. Managing the number of animals in captivity is dealt with by invasive non-native species licensing. 

Actions

Defra and the Forestry Commission already play a significant role in managing the population and adverse effects of grey squirrels, through advice and incentives for land managers, supporting collaboration and partnerships, funding research, and taking appropriate action in the nation’s forests. We will continue to take a leading role and will work with partners across the sector to implement the actions in this statement.

1. Landowner responsibilities and incentives

We will continue to ask land managers to assess the risks grey squirrels present to their woodland and add necessary actions to their woodland management plans to reduce grey squirrel impacts. Where landowners and managers receive public funds to reduce the negative effects of grey squirrels, we will require them to demonstrate they are doing this effectively.

Partners are working to improve grey squirrel management techniques to reduce costs and improve effectiveness while meeting animal welfare requirements. As soon as new equipment, such as traps, is licenced and approved, our grants will support its purchase. Landowners will have the latest technology available to support them.

In addition to professional practitioners, volunteers are critical to landowners in delivering grey squirrel management in England’s remaining red squirrel strongholds. Red Squirrels Northern England (RSNE) estimate that community volunteer groups were responsible for 80% of grey squirrel management reported to them across the red squirrel’s northern range in 2024. We will encourage landowners to make use of well-trained, competent volunteers in grey squirrel management across the whole of England.

Defra and the Forestry Commission will:

1.1 Continue to require woodland management plans in support of grant and licence applications to include actions to reduce likely impacts from grey squirrels.

1.2 Continue to support landowners to take action through Countryside Stewardship grants, including funding for appropriate capital items.

1.3 Increase the area of land covered by grey squirrel management options in environmental land management schemes from the 2022 to 2023 baseline.

1.4 Evaluate and support, as appropriate, new methods of grey squirrel management as they become available. We will use best practice methods where management occurs on public land.

1.5 Work with public bodies to agree methods of monitoring the impacts of grey squirrels on public land, where appropriate and practical.

Forestry England (an agency of the Forestry Commission) will:

1.6 Implement the results of their trial, which provided access by volunteers for grey squirrel management on Forestry England land, sharing the results and lessons learned with public landowners to encourage uptake of effective approaches and wider implementation across their estate.

1.7 Undertake grey squirrel management where necessary, practical and resourced.

2. Delivering through partnerships

Grey squirrel impacts are widespread, albeit with some regional variation. The negative interaction with red squirrels is well known and understood. 

There is a strong red squirrel conservation community, with significant experience and knowledge, targeting action in and around red squirrel populations. This action is being coordinated through the England Red Squirrel Action Plan led by the UKSA.

Coordination of of action across landscapes to manage grey squirrels will bring greater results than any one landowner acting alone, and ensures resources are used to the best effect. This requires planning and facilitation between neighbours, including public and private landowners.

Targeting action can help deliver on multiple objectives too. Focussing grey squirrel management activity in the counties bordering the established management groups in and around red squirrel populations has multiple potential benefits, which include: 

• reducing reinvasion of red squirrel territory
• reducing tree damage
• providing opportunities for red squirrel range expansion

Defra and the Forestry Commission will:

2.1 Continue to support expansion of the network of grey squirrel management groups and red squirrel conservation groups by funding project officers in Lancashire, Yorkshire, and County Durham, with the long-term aim of establishing county-wide grey squirrel management groups.

2.2 Continue to work with signatories of the UKSA to improve coordination of action and ensure collaboration across the sector. We will facilitate sharing of knowledge and best practice.

2.3 Work with partners to put the UKSA on a more sustainable financial footing from 2026.

2.4 Promote collaboration between neighbours to deliver landscape-scale grey squirrel management and consider how to support this within new environmental land management schemes or other relevant initiatives.

2.5 Promote management of grey squirrel impacts through relevant plans and strategies, such as local nature recovery strategies and management plans for Protected Landscapes and National Parks.

2.6 Work with Forestry England to investigate further opportunities to support pine marten populations in the Nation’s Forests.

2.7 Investigate further opportunities for pine marten recovery outside of the Nation’s Forests, working with partners like the Two Moors project, which reintroduced pine marten in Dartmoor and Exmoor.

Public bodies will:

2.8 Work collaboratively with each other and adjoining landowners to improve the effectiveness of grey squirrel management, where appropriate and practical, such as coordinating the use of traps and other management methods.

3. Research and development

Grey squirrels affect woodland ecosystems, particularly through selective ringbarking, which is the stripping of bark around the circumference of a tree’s trunk. This leads in some woodlands to tree deaths and can cause removal of a tree species from mixed woodland stands. Bark stripping exposes trees to fungal and insect attack, disrupts flow of nutrients up the tree and weakens the stem.

Current legal grey squirrel management methods are often described as ineffective by landowners because the work must be repeated each year to manage and reduce effects. There is also public support for non-lethal control. These are among the reasons why we have been supporting research on fertility control.

Creating a fertility control vaccine for grey squirrels has the potential to offer an alternative non-lethal management method to manage population densities and support local eradication efforts. The project is aiming to create an immuno-contraceptive that grey squirrels can ingest orally, accessed through a species-specific delivery mechanism – a bait hopper (a platform for the bait that only grey squirrels can feed from).

Other emerging non-lethal forms of population management include ‘gene drive’, which is a way of modifying genes to increase their chance of being passed on. This ensures that chosen characteristics, such as infertility, are carried through a population rather than eliminated through natural selection. In this way, grey squirrel breeding success could be reduced in the longer term. Gene drives are regulated as genetically modified organisms and would need authorisation prior to release. Authorisation is dependent on consideration of environmental risk by an independent expert committee and public consultation. A full understanding of the environmental risk would be a significant programme of work.

Pine marten presence alongside grey squirrels can also reduce their population and may help to restore ecosystem balance. We need to monitor the effect of resurgent and reintroduced pine marten populations on grey squirrel populations to see if the population changes observed in Ireland and Scotland are as successful in England.

Defra and the Forestry Commission will:

3.1 Continue to support research, led by the UKSA and carried out by the Animal and Plant Health Agency (APHA) into an oral form of fertility control.

3.2 Support research to quantify the effects of grey squirrel damage on woodland ecosystems.

3.3 Work with research funders to address evidence gaps and encourage funding through their relevant programmes – including research into the role of grey squirrel damage in tree disease and woodland composition.

Forestry England will:

3.4 Continue to monitor pine marten populations in the nation’s forests and their effect on grey squirrels, in particular following the Forest of Dean reintroduction project.

4. Communication

To support land managers, their advisers and representatives, conservation groups, and volunteers, we will share evidence on the need for effective management measures.

Defra and the Forestry Commission will:

4.1 Develop an in-depth communications plan to enable us to reach priority audiences with clear messages regarding the management of grey squirrels. We will work closely with key partners to begin delivery of this from the outset of this statement.

4.2 Continue to work with the UKSA and the wider sector to communicate the importance of grey squirrel management to the public, referring to relevant research.

5. Guidance, training and skills

High quality training and standards across the sector are essential for safe, humane and effective management of grey squirrels. Reducing grey squirrels’ impacts will require a greater number of skilled managers and volunteers, and improved levels of knowledge within the woodland and forestry sector at both the practitioner and land manager level.

Defra and the Forestry Commission will:

5.1 Continue to support land managers to access grey squirrel management training through incentive schemes.

5.2 Work with partners to increase sector skills and capacity, including funding forestry apprenticeships and other stakeholders on vocational training and sector skills.

5.3 Work with the UKSA to promote training and produce a training webinar on conducting impact surveys and creating a squirrel management plan by summer 2026.

5.4 Review and disseminate good practice guidance on managing grey squirrels when new techniques or improved management methods are available.

The Forestry Commission will:

5.5 Continue to include effective squirrel management in its apprenticeship programmes, which will train up cohorts of future foresters.

Delivery

Defra, the Forestry Commission and other government organisations will take forward these actions over the next 5 years and will ensure that all actions are delivered. The Defra group will review the delivery of this policy and publish a report on progress by the end of 2031.

The objective of this statement is to substantially reduce the impacts of grey squirrels. We will measure success by:

• monitoring and reporting on grey squirrel effects through the five-yearly National Forest Inventory (NFI) survey – the NFI data records damage observed in sample squares across all woodland types in England
• assessing grant scheme data, including reporting on the area of grey squirrel management supported by environmental land management schemes – we expect this to increase from the 2022 to 2023 baseline
• assessing the change in numbers of tetrad squares in England containing red squirrels from a 2021 baseline
• determining the change in economic impact of grey squirrels

Defra and the Forestry Commission look forward to continuing to work in partnership with the UKSA and all our stakeholders to substantially reduce the impacts of grey squirrels on England’s trees and woodlands.