Weekly Nature Watch

The Tide of Autumn

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The tide of autumn has really begun to run as suddenly there is a deluge of leaves and almost as abruptly, overnight, the landscape now glows with greater intensity, as the autumn colours with each passing day, strengthen. Now we see a landscape enjoying its final, vibrant fling, blazing golden and red in a last joyous gesture, before winter closes in. And this final flutter surprisingly has its own musical accompaniment as redbreast continues his sweet soliloquy … except he is not after all a lone songster, for he has been joined by another, very appropriately, a solitary jenny wren.

His song, though not as sweet in tone as that of the robin, is nevertheless cheery and vibrant in the extreme and typically delivered with the kind of panache that seems to be the exclusive prerogative of the wren. His is a rat-a-tat-tat message of territorial integrity that astonishingly, may deliver as many as a hundred notes in as little as eight seconds! Thus he shares with the robin a vocal pronouncement of claim over a winter feeding territory. But then the robin and the wren have always somehow been linked. An old verse for instance, deems that to harm a robin or a wren is sure to bring ill fortune to the perpetrator … be he boy or man!
 
Another declares that ‘the robin and the wren are God Almighty’s cock and hen’, a declaration that seems to emasculate the poor old wren, which of course is commonly known as ‘Jenny Wren’. The rat-a-tat merchant in my orchard, make no mistake, is no shrinking violet. Rather is he a fiesty, red-blooded cock bird, like his robin compatriot, ready, willing and able to defend that territorial integrity against all comers (as long as they are rival, cock ‘jenny’ wrens of course).
Perhaps because both are inhabitants of similar habitats, typically gardens or indeed woodland, are seen to be ‘perky’ little birds, full of jauntiness, readily known for the ‘attitude’ they exude and of course both sing during the bleak winter months, they are inevitably linked with each other. Indeed they both seem to enjoy the company of people, often finding nesting sites in sheds, in discarded kettles, old clothes and a whole host of other curious places. That both provide music during the otherwise barren winter months of the year also strengthens that link. Indeed, they were in the past, widely thought to be the cock and hen of the same species. 
 
Surprisingly perhaps, the wren is said to be the most numerous of all British birds with an estimated eight million of them thought to live in Britain. However, although we may regard the wren as a bird of parks, gardens and woodlands, some are able to exist in the unlikeliest of places. The remote, treeless islands of St Kilda for instance, boast a population of wrens, which in such isolation have even evolved in such a way as to deserve the status of a sub species. The St Kildan wrens are marginally larger than their mainland cousins as are wrens on the almost equally isolated Fair Isle, in the Shetlands and the Outer Hebrides.
 
As the diet of wrens comprises of spiders and other insects, bad winters can hit these tiny birds particularly hard. There were, it is known, huge losses of wrens during the severe winter of 1962/3 and indeed their absence here since the harsh winters of 2009/10 is further testimony to their vulnerability. However, even after such disasters, they seem to bounce back and recover their numbers in a relatively short time. As a means of combating adverse conditions, wrens sometimes act corporately by packing themselves in large numbers into confined spaces such as artificial nest boxes so as to share in the heat so many little bodies can generate. 
 
Many birds of course choose not to face the rigours of winter and instead fly south, in some cases over vast distances, to enjoy what the tropics have to offer. However the tiny wren, not the most powerful of flyers, does not see such flights of fancy as an option. So they face forthcoming winter with trepidation, with no food reserves in hand and as a result they are clearly vulnerable if the winter is lengthy and harsh.
 
Other creatures do make provision. Some of course, choose the long sleep as their means of escaping the winter months. Hedgehogs and bats hibernate, sleeping through the worst of the weather. The success of this tactic, at least as it is employed by hedgehogs, depends upon how well they have feasted during Nature’s harvest time and how much body fat they have accumulated. This fat is the reserve upon which they will depend as their systems slow down and sleep overtakes them. For others however, the collection and storage of surpluses in caches, carefully laid up for those hard winter days when natural food sources are scarce or even non-existent is their means of winter survival. Famously squirrels bury nuts in vast quantities during the autumn.
 
A recent search for sloes revealed a cupboard, which this year is almost bare. Conkers, the fruits of the horse chestnut, are also very scarce this autumn but there does, on the other hand, seem to be a good supply of acorns for which I’m sure, those for whom the fruits of the oak are vital for winter survival, will be grateful. Amongst those creatures for which acorns are an important winter supplement, are jays. Indeed, this, the most colourful member of the crow family, is as far as I can work out, the only avian creature that has the wit to lay stores of any magnitude in for the winter months. But then, as often remarked before, the crow clan in general is blessed with surprisingly high intellect.
 
Such is the energy devoted to this collection and storage of winter supplies that jays are said to be responsible for a remarkable degree of oak woodland re-generation. I guess that makes jays ardent conservationists! The extent to which these amazing birds will go in order to establish meaningful winter stores is illustrated by studies made by a scientist back in the nineteen fifties. His observations revealed that a single jay could store enough acorns in an autumn season as to produce a small forest! Carrying just three or four acorns at a time, the bird averaged some sixty flights during each ten-hour day. It was estimated that in total, it stored as many as 5,000 acorns that autumn! 
 
The jay perhaps gets a worse press than it deserves, perhaps because it is often tarred with same brush as its fellow crow clan member, the magpie. It is guilty in the spring of the year of taking the chicks of other birds but it is also deserving of merit for its colourful plumage. Its pink, going on chestnut body gives way to striking black and white on the wings and tail, a prominent white flash on the rump is what is often seen as the bird flies away from you. More subtle, is the flash of azure blue on the wings, all of which moved one ornithologist to dub it, "The British bird of Paradise!" Pity it can’t really sing!
Any natural place contains an infinite reservoir of information, and therefore the potential for inexhaustible new discoveries.

Richard Louv, Last Child in the Woods