A rare colony of red squirrels has been discovered on a tree plantation in the Yorkshire Dales.

The endangered species was identified by Julie Bailey from the UK Squirrel Accord (UKSA), a partnership of forestry and conservation organisations.

Ms Bailey said she initially found four red squirrels in the North Yorkshire sitka spruce plantation after using thermal imaging cameras to survey the land.

She then placed two cameras in the area and found the colony had moved in. The landowners said they were “delighted” and now plan to manage the landscape with the red squirrel population in mind, UKSA said.

The plantation of sitka spruce – used extensively for timber and pulp production, but also for Christmas trees – is in the western part of the Dales in North Yorkshire.

The red squirrels had never been identified in the plantation before, but Ms Bailey believes the colony will now prosper and increase.

Project Officer Ms Bailey said: “The plantation owners gave permission to survey a specific area using thermal imaging technology that picks up body heat.

“I found four individual red squirrels. I then placed two cameras in the area and was able to confirm a new colony of red squirrels.

“The plantation owners were delighted.”

Red squirrels are native to the UK but their population has been driven to the verge of extinction by grey squirrels.

There are thought to be just 160,000 red squirrels left in the UK, with their population now mostly restricted to Scotland, Ireland, parts of Northern England and the south coast.

The landowners have given Ms Bailey permission to extend her survey to cover the whole of the plantation.

A new volunteer group, The Yorkshire Dales Red Squirrel Alliance, has been established as part of a pilot project to protect red squirrels and tree health.

It is funded by the Forestry Commission, which is a UKSA signatory, with local volunteers encouraged to join.

Ms Bailey said: “One local volunteer who lives close to the plantation has, for some time, been managing non-native grey squirrels and his work has enabled these reds to move into the plantation.”

There are other red squirrel populations within a few miles of the plantation and Ms Bailey is optimistic for the future of the native species in the Western Yorkshire Dales.

Rebecca Isted, Forestry Commission Squirrel Policy Advisor, said: “Our native red squirrels are an important part of our natural heritage and the discovery of a new population in North Yorkshire is a positive step in our shared aim to protect, identify and strengthen populations across England.

“Red squirrels are endangered and we estimate there are fewer than 40,000 left in England.”

The organisation was “committed to supporting the survival and recovery of our native species in woodlands across the country,” she said.

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