The red squirrel has come under increasing threat
Red squirrels are returning to areas of Scotland where they have not been seen for years, according to campaigners.
Efforts to control the more aggressive grey squirrels have allowed the reds to regain territory in parts of Aberdeen and Tayside.
Grey squirrels had been gradually squeezing the native reds out of Britain's woodlands since their introduction from the US a century ago.
It is thought only 121,000 reds - most of the UK total - remain in Scotland.
For the past year Saving Scotland's Red Squirrels (SSRS) has been working to check the spread of grey squirrels and to halt a virus which affects only the reds.
They have reported signs of a red squirrel revival, particularly in parts of Aberdeen, including Cults, Countesswells and Bieldside in the city centre.
Speaking at a conference discussing the issue in Perth, SSRS project manager Mel Tonkin said: "It's heart warming to know that Scotland's red squirrels and the communities lucky enough to still share the natural world with these amazing creatures are the ones beginning to reap real rewards.
"In the north east, thanks to a programme of carefully planned grey squirrel control activity, we can report that red squirrels are now being spotted in areas of Aberdeen where they hadn't been seen for several years.
"This indicates that grey squirrel control is necessary action which not only protects red squirrels from further decline, but allows local populations to return to areas they inhabited before the arrival of the grey squirrel."
He added that in Tayside an increasing number of landowners were committed to controlling grey squirrel populations on their land and helping the SSRS to monitor its effect on red squirrels locally.
"With our project soon to appoint a project officer for west Scotland and with our sister project, RSSS, continuing its important work to contain squirrel pox in the south, we now have all the tools in place to give red squirrels the best chance of retaining its place as one of the best-loved icons of Scottish wildlife for many years to come."
Under the UK Biodiversity Action Plan, the red squirrel is one of the first species identified as requiring conservation.
Environment minister Roseanna Cunningham said: "The red squirrel is one of our most iconic and beautiful species and we must do everything we can to protect it.
"The organisations involved with Saving Scotland's Red Squirrels have shown real vision in coming together to save the species."