Conservation efforts see red squirrel numbers increase

Saving Scotland’s Red Squirrels (SSRS) is a partnership project, led by the Scottish Wildlife Trust, working in key areas across the country where populations of red and grey squirrels meet.

The Highland Line control zone is a priority area for the project, following the Highland Boundary Fault, a geological feature which acts as a natural barrier to invasive non-native grey squirrels, limiting numbers traveling into the red squirrel stronghold of the Highlands and Grampians.

This zone covers significant parts of the Angus, Aberdeenshire, Perth and Kinross, Argyll and Bute, and Stirling council areas.

SSRS project partners, a dedicated network of volunteers and individual landowners are doing their bit to defend the Highland Line, preventing any incursions of grey squirrels to the north and expanding red squirrel territory to the south.

Monitoring and humane lethal control to remove grey squirrels create safe habitats for red populations to recover.

Greys outcompete red squirrels for food and habitat, and can replace an entire population of red squirrels within 15 years. Some also carry the squirrelpox virus, which does not affect them but is deadly to reds if transmitted.

There has never been a case of squirrelpox recorded along the Highland Line, and there has only been one positive case north of the Central Belt, in Dunfermline in 2024. Keeping the number of grey squirrels down in this area means an outbreak is less likely to occur.

At Strathmore Estates at Glamis, dedication from SSRS staff and the estate has led to a significant decline in grey squirrel numbers. In 2022, red squirrels were a very rare sight on the grounds. This year, they are now the most commonly seen squirrel species.

Working with the National Trust for Scotland at the House of Dun Estate, near Montrose, SSRS detected one grey squirrel in July, through a hair sample left at a monitoring feeder box. Since then, no further grey squirrels have been detected.

At Sunnyside Estate, also near Montrose, and the surrounding area, no grey squirrels have been detected since March 2025. Across East Angus, the greys’ breeding populations have been reduced to just two locations, where control is being carried out. With populations significantly reduced in this area, SSRS’s primary activity is now monitoring to confirm presence or absence of grey squirrels.

Jen Payne, conservation lead for the Highland Line, said: “It is really encouraging to see red squirrel populations recover. We know how important this area is for preventing the spread of grey squirrels further north, so our work to defend the line and hopefully expand red squirrel territory further south is vital to protect the red squirrels of the Highlands and the North East.

"We’re grateful to have so many passionate volunteers, partners and landowners helping us to look after this iconic species.”

The public can support the project by reporting squirrel sightings – red and grey – to the SSRS website.