The British Trust for Ornithology annually mobilises thousands of volunteers to carry out counts in a variety of habitats as part of its Breeding Bird Survey, which monitors the health of the UK’s birds. There is an inevitable time lag between the data being collected and the results published, but we now have the figures for 2018. One interesting trend is that for nuthatch; nationally, the population has been rising for the past quarter of a century, as shown by the thick line on the graph below. At Blean Woods during this period, however, there has not been the same encouraging trend (dotted line). The numbers have been adjusted so that both the national and local populations start from an arbitrary 100, which makes the disparity in subsequent performance all the more striking. It is far from clear why the population in East Kent should have been bucking the national trend and, while it looks as though numbers at Blean Woods may now have stabilised, there is no sign of a major resurgence.
It seemed as though we were blessed with a prolonged feast of autumn colours, the bright yellow birch trees resisting the onslaught of November winds for weeks longer than usual, but the seasons cannot be postponed indefinitely, and the abscission layers being laid down at the base of countless millions of leaves meant that they were being irretrievably weakened, and when the foliage was spangled with the first frosts a trickle of falling leaves soon turned into a rustling torrent, the lightest of breezes freeing them from their summer anchorage. Now the woods are completely bare, the bleakness of winter is upon us, and the only clutched straw preventing the onset of depression is the thought that the days will start lengthening (imperceptibly) just before Christmas.
One of the joys of nature is that it periodically presents us with plants and animals that deviate from the norm – the raw material on which Darwinian selection can act. These deviants, or mutations as we now know them to be, are being thrown up all the time, most never seeing the light of day because they are less able to cope with their environment, but one that crops up regularly at Blean is the albino squirrel, and I was recently able to snatch a photo as a spectral figure scampered up an oak tree beside the access track. This individual has been around for some time, apparently disproving the assumption that sticking out like a sore thumb would lead to its early demise, but it must be at a disadvantage, or else the trait would spread through the population. Still, come the next ice age, our white friend would blend in nicely against a snowy background.
Michael Walter
michaelwalter434@gmail.com
Our very own albino squirrel
Nuthatch courtesy of Dave Smith
I've got three white-furred squirrels in my garden, and at least one has been there for over 2 years. Shows predation can't be that strong.