Red squirrels re-appearing thanks to the pine marten
These are encouraging times for red squirrels, significantly better than when, in the late 19th century, a craze developed which saw the alien American grey squirrel brought to this country.
It was a certain Mr Brocklehurst, a landowner from Cheshire who brought the first of these subsequently unwelcome squirrels – two pairs of them – and released them on his estate. Inevitably, they went forth and multiplied … with a vengeance! That first introduction occurred in 1876 after Mr Brocklehurst had seen such animals cavorting in New York’s Central
Park and, thinking how charming they were in that setting, arbitrarily decided they would be equally entertaining in this country.
Sadly, he was not alone. In subsequent years, other landowners, not to mention some civic organisations, followed his example and soon grey squirrels were scurrying about all over the place. The first to arrive in Scotland came to the shores of Loch Long in 1895 but by the 1920s, they had so well established a presence especially in the south that young squirrels from sites in England were being freely sold to be released elsewhere in the UK. Not a thought had been given to what the consequences of the impact of this introduction might have on our native red squirrels.
In time, it was apparent that the aggressive nature of grey squirrels would have a seriously deleterious effect on the smaller red squirrels which were unable to compete with the greys for food sources. Furthermore, the reds were exposed to a deadly virus carried by the grey squirrels to which they were immune but the reds were not!
The folly of introducing alien species has since been thoroughly exposed as red squirrel populations have plummeted, except perhaps across Highland Scotland. Yet the lessons were not learned. During the 20th century, mink farms were set up here, the animals also coming from America. Inevitably, some escaped and established themselves in the wild. Even worse, when the bottom dropped out of the mink-fur business, farmers, unable to feed their mink, just released them.
Further devastation occurred when anti-fur farming folk released mink from farms as a means of protest.
The devastation that followed saw many ground nesting birds in the areas close to such releases, fail to rear any chicks for a number of years. The native water vole also disappeared from large swathes of the UK landscape thanks to the predation of mink.
Mink are severely controlled these days but continue to wreak havoc in some places where they are still a force. Water voles, their chief victims, are being re-introduced to many rivers across the UK and mink control has been intensified but until mink are finally eliminated altogether, Kenneth Grahame’s ‘Ratty’ may continue to struggle.
Now another introduction, this time of stoats to Orkney, threatens a whole host of birds and animals native to and precious to those islands. The first stoat was seen there in 2010 and so concerned are folk about the devastation that might occur should they establish themselves that a major scheme to eradicate them is underway. Curiously enough, neither the Edinburgh or London Governments are making a contribution to the tackling of this problem!
The threats these interloping stoats pose are manifold, with the last really significant realm of our hen harriers, which is in Orkney, under threat through predation of harrier eggs and the effect the stoats may have on one of the main sources of harrier food, the unique Orkney vole. The Orkney vole has developed in isolation from its mainland cousin and has reached a size almost twice that of a mainland vole.
Indeed, stoats threaten a whole range of ground nesting birds in Orkney where wildlife is understandably regarded as an asset of considerable substance, a vital factor in Orkney life. No-one seems to know how the stoats got there in the first place but some suspect that this was a deliberate introduction as stoats have never before been among Orkney’s diverse wildlife icons.
There are bitter ironies touching so many aspects of the introduction across Britain of non-native species of all manner of plants, animals, marine organisms and birds. In many parts of southern England, parakeets have firmly established themselves and their noisy presence in gardens is becoming increasingly evident. These originated from the escape of captive birds but when we look at the invasive plant species, they are literally all around us. During previous centuries, plant collectors from Britain toured the world in search of plants which were thought would enhance the British countryside.
Now some of these species are overwhelming some native species as witness the rhododendron bashing that has become a common conservation strategy. There are many others which also have a negative impact, giant hogweed and Himalayan balsam among them.
The ironies about the squirrel equation is that there was a time, prior to and during the introduction of grey squirrels, when our native reds were targets of clubs set up to reduce squirrel numbers because of the damage they caused to new plantations of trees. The Highland Squirrel Club for instance, was set up in 1903 and in the next 30 years no fewer than 85,000 red squirrels were killed by its members! However, the deleterious effect of grey squirrels completely turned attitudes around and these days it is the grey that people wish to see the back of with hopefully, red squirrels returning to fill the void.
Coincidentally, a perfectly natural solution has arisen with the spread of the pine marten across many parts of Scotland and now, with a little help, into parts of England and Wales.
This beautiful arboreal predator had been massively persecuted during the killing years when many aspects of our wildlife were devastated with the rise of the sporting estate. Indeed, pine marten very nearly followed ospreys, sea eagles and polecats into extinction in Scotland.
Fortunately, they managed to cling on in some more remote areas of the Highlands. Given legal protection in 1988, pine marten soon began to respond, re-occupying areas from which they had been forcibly removed and in recent years they have quickly spread to many areas where grey squirrels had established themselves as dominant.
Grey squirrels are considerably heavier than red squirrels and as such provide martens with easier prey to catch. Furthermore, once caught they provide excellent eating! Here, as elsewhere, the activities of pine marten have had a transformative effect upon the grey squirrel population, virtually eliminating them. Happily, there were present, enough red squirrels to fill the void and now I hear that red squirrels are being seen in Stirlingshire villages for the first time in living memory, thanks probably to the intervention of pine marten in the vicinity. In addition, red squirrels have been re-introduced to forests in the north from which they have long been absent.
The lighter red squirrel does sometimes fall victim to pine marten but as they are able to reach the thinner branches of trees where marten fear to tread, giving them much better opportunities to survive, they seldom fall victim.
I’m absolutely convinced that the introduction of pine marten into the Forest of Dean in Southern England will quickly result in a welcome reduction in grey squirrel numbers there. Maybe also red squirrels, freed of the competition of greys, will become re-established. It is becoming the natural way of restoring the balance.
It is now many years since I first came across pine marten in this airt. I had previously travelled to places like Ardnamurchan and Wester Ross to see them. My first sighting here was of a marten running across the road near our local loch but there followed other experiences including an incident in which a pine marten reared her family in the roof space of a house belonging to a friend.
We were richly entertained by the family of martens which in no uncertain terms confirmed that a population was beginning to establish itself here. Indeed, I responded to a request by a local resident as to what had happened to their bird feeder, subsequently found a few hundred yards away from their garden. The culprit from description, a pine marten! So, in recent times there has not been a grey squirrel to be seen!