While humans have proven to be incapable of protecting the red squirrel, it turns out that their survival may be in the hands of another species – the humble pine marten!

Plans are afoot for pine martens to be deployed as wildlife bodyguards along the east coast of Scotland to stop the continued northward spread of the grey squirrel.

At least 35 artificial pine marten dens are being created by Forestry and Land Scotland (FLS) at strategic locations to try to save the Highland red squirrel populations.

Since the introduction of the grey squirrel to the UK in Victorian times, the red squirrels have been driven out of most of the British countryside. Grey squirrels can not only outcompete the red, but they carry the squirrelpox disease which leaves them unharmed but is fatal to the reds.

But it appears that there is one area where the red has a significant evolutionary advantage over their grey cousins – and it comes in the form of the pine marten. Research has shown that the predatory pine marten has reduced grey squirrel populations significantly, while leaving the native red squirrel populations stable.

Red squirrels and pine martens evolved alongside each other over thousands of years. Because of this, the reds have natural evolutionary defences against the pine marten. For grey squirrel, however, this is a relatively new foe and one which it is yet unable to cope with.

There are great fears that the northward-marching greys from Scotland’s central belt will meet the Aberdeen population and quickly expand, endangering reds across north-east Scotland.

However, it is hoped that the pine marten dens will increase the population density of pine martens and ensure they are living in areas where they can hunt the greys. The science is supported by real-world examples of resurgent pine martens alongside prospering red squirrels, which have returned to parts of Aberdeenshire where they haven’t been seen for many years.

The dens are roofed, wooden boxes attached to trees around five metres off the ground and stuffed with wood shavings. This offers a pine marten a secure and cosy place to shelter and breed. On the ground, pine marten nests are vulnerable to predation from foxes.

Dens will also be installed farther east, around the A90 in Angus and along the A9 corridor.

However, recent studies have shown that pine martens won’t establish in urban areas, giving the grey squirrels a stronghold. This means that if the countryside is constantly supplied with new grey squirrels from urban strongholds, the species is likely to eventually adapt to survive alongside the marten.

According to Gareth Ventress, an environment forester at FLS, “Pine martens are not the answer to the grey squirrel threat by any stretch, but they are part of the answer. The key to this pine marten-grey squirrel relationship seems to be pine marten density. With the boxes we can potentially localise some of the pine marten population.”

“Keeping the grey squirrel populations back will help us diversify, and nature and woodland restoration has a better chance,” added Ventress.


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The declines in our wildlife is shocking and frightening. Without much more support, many of the animals we know and love will continue in their declines towards extinction.

When you help to restore a patch of degraded land through rewilding to forests, meadows, or wetlands, you have a massive impact on the biodiversity at a local level. You give animals a home and food that they otherwise would not have had, and it has a positive snowball effect for the food chain.

We are convinced that this is much better for the UK than growing lots of fast-growing coniferous trees, solely to remove carbon, that don’t actually help our animals to thrive.

This is why we stand for restoring nature in the UK through responsible rewilding. For us, it is the right thing to do. Let’s do what’s right for nature!

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