Weekly Nature Watch

Country View 26.4.16

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Confusion reigns! Last week’s benign conditions during which spring definitely seemed to be springing, have given way to a sharp downturn of temperatures to those more closely associated with February rather than April. The cause? Apparently this sudden drop is due to the juxtaposition of high and low pressure areas respectively to the west and east of us, which are drawing air down from the Arctic. The sun may continue to shine but that northerly wind reminds us that we are, after all, situated in the northern hemisphere not that far distant from the Arctic Circle.

As a result my supplies, especially of nyjer seed and sunflower hearts are fast diminishing as the flashing colours of the goldfinches and siskins continue to dominate. But also constantly present, hovering up the resulting detritus, are pink breasted cock chaffinches. Chaffinches like many other small birds, surrender their singularity for the security of the flock during the winter months but they do so on a strictly gender based single sex structure. Significantly, although the air is definitely filling with the cheerful chattering of cock chaffinches, all the birds currently feasting under my bird-table, are also cock birds, perhaps reluctant to cast off their winter mind-set whilst the north wind blows.

On the one hand therefore, the cold Arctic blast is persuading these birds to remain for the present together in winter format, yet their hormones are telling them that the breeding season is indeed imminent, for there are spats occurring constantly as an instinctively competitive edge of rivalry infects them. There is also likely to be confusion among those migrants already arrived, A day or so ago, I watched at exceptionally close quarters, a pair of house martins, inspecting with great enthusiasm the nest which presumably they used last year.

Although the ospreys have been back with us for a week or two now and in the past few days I have heard the first, sweet, down-the-scale incantations of a willow warbler, I’m not at all sure what they may be making of the cold conditions. For the ospreys there will not be much of an issue. There are, after all, plenty of fish not necessarily in the sea but in our fresh water lochs, largely as far as I know, unaffected by temperatures. But for the more adventurous swallows now turning up, that willow warbler and the house martins, insect life is the key issue and the cold conditions will inevitably restrict their availability.

Ever since I was a boy, maps have fascinated me. It will come as no surprise therefore that I do not have, nor do I wish to have, Sat Nav! Our increasing reliance upon technology prompts the question whether future generations will be able to read standard maps at all! From what I hear, this new technology can sometimes cause utter confusion too. For instance, living in a rural environment, our post code naturally covers not a few houses in one street but several square miles. As a result delivery van drivers sometimes have great difficulty in finding us. And of course there are tales of lorries getting stuck in narrow lanes, their drivers led into such ‘traps’ by the same Sat Nav and indeed reports of users finding themselves in fields or indeed rivers and even the sea!

All of which, set me thinking about the newly arrived martins which, after navigating their way over several thousand miles from darkest Africa, crossing deserts, seas and mountain ranges, found their way not just to Britain but to Scotland and even to a tiny village and a nest on a building which they probably last saw around six months ago when they departed these shores. Now that really is navigating … and without the said Sat Nav albeit that even if they are unable to tune in to our technology, they are nevertheless, amply equipped with a technology of their own – an in-built Sat Nav if you like!

These days of course, house martins nest almost exclusively on man-made structures, most popularly under the eaves of our houses. However, it is a fair bet that countless generations of these attractive little birds, so full of verve and athleticism, have been coming here since the ice sheet retreated. Then doubtless, they would have nested largely in caves and below overhanging cliff edges. Some still choose such locations although the vast majority now use buildings of one form or another. This is of course, why they are called ‘house’ martins, a nomenclature they share exclusively in the avian world, with ‘house’ sparrows.

This week, the 400thanniversary of Shakespeare’s birthday was celebrated. Well the English bard was certainly a keen observer of things natural and in his ‘Scottish play’, he certainly has martins nesting on the walls of Cawdor Castle; “This guest of summer, The temple haunting martlet …. Hath made his pendant nest and procreant cradle …”. Castles and churches are also renowned as places where martins build their nests.

This is perhaps why we have a special relationship with martins and why in times past they were, together with their close cousins, the swallows,  referred to as “God Almighty’s birds to hallow” - in some versions – “God Almighty’s mate and marrow”. However, martins are, curiously enough, also shrouded in mystery, for there is utter confusion as to exactly where they winter. Although down the years, thousands of British breeding martins have been ringed, as far as I know only two have ever been recovered in Africa, one in Nigeria and one in Senegal. The long and the short of it is that no-one knows where martins go in the winter. If sub-Saharan Africa is the known general destination of these fast flying migrants, detail of exactly where they go is a complete mystery. It is well to remember that Africa is large – the second largest Continent on earth.

Ironically, sophisticated technology is about to solve this problem. The British Trust for Ornithology is to use satellite technology in the shape of shirt button sized transmitters which are to be fitted to some martin’s legs. These mini computers will transmit signals which will at last identify exactly where these birds go during the winter months. Currently, it is conjectured that they spend most of their time there on the wing, high above Africa’s huge forests, gorging on the prolific insect life to be found there. Being places where very few humans live, these birds, if they are there, are therefore, seldom seen. Now a form of Sat Nav will help unravel their whereabouts next winter.

Such knowledge is important because it is known that house martin populations are currently in quite serious decline. The more information we can gather the more likely are we to find reasons for this decline, so that measures can be taken which hopefully may reverse this sad trend.

Hopefully, with the merry month of May just around the corner, the winds will soon begin to blow from warmer points of the compass and our intrepid, returning martins will survive to entertain us with their wonderfully buoyant flight as they pursue those pesky flying insects which are their means of survival and in many cases the cause of so much of our itching! After all swallows and martins are in our minds, the very essence of our summer.

Any natural place contains an infinite reservoir of information, and therefore the potential for inexhaustible new discoveries.

Richard Louv, Last Child in the Woods