Winter coats are welcome at this time of the year
Substantial snowfalls last weekend brought things to an abrupt halt on some of our major roadways!
This has been a snowy winter thus far, making it tough not just for drivers but for much of our wildlife too. Indeed, the helping hand we give to the birds will have been especially valuable this time round.
Some of our wild creatures are better equipped than others to handle such conditions and are prompted to change their coats accordingly. Up on our mountains, those who venture to such places to enjoy some ski-ing, winter walking or mountain climbing will be familiar with both ptarmigan and mountain hares.
However, the stoats, which also undergo this transformation and miraculously become ermine, are perhaps more familiar at lower levels.
Of course, it is not within the gift of any of these creatures to change their coats at will. Rather does the change in coat come in response to a combination of factors, one of which is definitely not true. Once upon a time, there were those who believed that a stoat only had to eat snow in order to change its coat to white! The change of coat is, of course, caused not by such activity but by climatic conditions – the shortening of daylight hours and lowering temperatures being the principal triggers.
Thus, ptarmigan and mountain hares automatically change their plumage and pelage respectively because they dwell at higher altitudes. Stoats do not necessarily go through a complete change and may end up almost piebald. In some cases, especially those animals that dwell close to sea level don’t change at all.
Elsewhere in northern Europe, one other animal, the weasel, also changes its coat although to my knowledge, weasels resident in these islands show no inclination at all to do so. This change of coat certainly offers both ptarmigan and mountain hare an exceptionally useful means of obfuscation, living as they both do in terrain in which eagles regularly patrol the skies above their largely snow covered territories. The degree of camouflage can indeed be remarkable and I have personally witnessed both these creatures only becoming visible when they moved!
In recent years, there has been concern about declining populations of both ptarmigan and mountain hares and several estates no longer shoot them. Incidentally, the mountain hare is our one and only native hare, the brown hare having been introduced here thousands of years ago.
The mountain hare is somewhat smaller than the more familiar brown hare, weighing perhaps a third less, having shorter ears and legs. It is often referred to as the blue hare, its summer coat having a bluish grey tinge. When, as winter descends, it changes its coat to white, the ear tips remain black. Sometimes, more southerly based mountain hares may not completely change their coats and this led to some early naturalists calling such animals ‘variable’ hares. Some even suggested that these were crosses between mountain and brown hares. However, there is no evidence whatsoever that these two animals interbreed. Scottish hares were introduced at various times to the Isle of Man, various locations in the Pennines and to North Wales. There may also have been an introduction locally to the nearby mosslands in this airt for I well remember many years ago accompanying a colleague on to the mosses where we had been asked to pass comments on a proposal to extract peat commercially. During our survey we had blue hares springing almost from under our feet. Happily, the proposal to extract peat was refused.
Whilst there are plenty of brown hares lingering around those mosses these days, there are now no mountain hares. I suspect therefore that they may have been introduced to this low ground by some of the shooting estates, perhaps early in the 20th century.
Recently, I watched an item on TV about Canadian lynx. They depend almost entirely on mountain hares for food and it set me wondering about the possible re-introduction of lynx here and the impact that might have on our mountain hares.
I have had several close encounters with stoats and weasels, albeit that hereabouts the population of both seems to have plummeted in recent years.
There are one or two hotspots where I still see them but not in the numbers I used to. I guess the main reason for their demise is the absence of rabbits, probably the stoat’s main source of food in particular.
I once sat entranced by the ‘square dance’ being conducted by a single weasel. I was sat in my car at the time, enjoying a lunchtime sandwich, when I became aware of lots of little birds in the surrounding hedges on either side of the track on which I was parked. They seemed fascinated by something. That ‘something’ was a weasel which, as I watched, began to run up one side of the track, cross over and run back down the other side … repeatedly, doing that strange square dance time and time again. I soon realised that the assembled birds were actually coming down the branches of the hedges as if to get a better look at the dashing, dancing weasel.
And of course, that was just what the weasel was hoping for. Eventually, one particularly ‘hypnotised’ bird flew down to the track. In a flash, the game was over. Lunch had been served. I also watched a stoat in my own garden perform a similar stunt only this time it took the form of a series of tumbling and twisting acrobatics which similarly hypnotised the birds until one dunnock ventured just that bit too near and accordingly paid the price!
The ability of this trio of creatures to turn white and thus acquire that quite marvellous camouflage when snow lies thick on the ground, is one of nature’s neatest tricks. It enables the two mountain dwellers, to go about their plant eating days with the threat of those sharp eyed eagles making a meal of them substantially reduced. The more avaricious stoats dressed regally in their coats of ermine now possess that cloak of anonymity which will make them even more rapacious hunters.