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| Alpine Swift - species with 'vast powers of flight' |
This month has seen a remarkable influx - numbering more than 150 individuals - of Alpine Swifts to Great Britain. Below is an extract from The Birds of Great Britain, written and illustrated in 1873, by John Gould
The Alpine Swift is a summer visitant to the central and southern portions of Europe.
As its name implies, it is also a denizen of the Alps, and, I believe, of the Apennine ranges also - rocky regions appearing to be peculiarly attractive to it, although it is said also to frequent plains.
In Berne and Fribourg, besides many other places, it is known to breed in the steeples of the cathedrals and churches of those fine old towns.
Like the Common Swift it is a migrant, and in the early part of autumn leaves all the parts of Europe it frequents, and passes into Africa.
How far its range extends southward in the latter country is not known, the bird from the Cape Colony formerly supposed to be the same having been ascertained to be a distinct species.
Besides being dispersed over Central and Southern Europe, the Alpine Swift is abundant in the Holy Land, Asia Minor, Persia, and, doubtless, all the intervening countries to Afghanistan and Western India, where, as will be seen by Mr. Jerdon’s notes given below, it is very numerous.
Almost every person who has had an opportunity of observing this bird speaks in terms of admiration of its vast powers of flight: it is not surprising, therefore, that an individual should now and then wing its way across the Channel to the British Islands, and course over our meads and fields until it is shot.
Its occurrence here is almost exclusively confined to England; for I find no record of its having been seen in Scotland, and only two instances of its having been killed in Ireland.
The first specimen known as British was shot early in June 1820, by the bailiff of the late R. Holford, Esq., at Kingsgate, in the Isle of Thanet, and is now, I believe, in the possession of R. B. Hale, Esq., of Alderley Park, Gloucestershire.
Since that date a few more examples have been killed in this country - one in Norfolk, another in Essex, a third in Kent, a fourth in Cambridgeshire, a fifth in Berkshire and a sixth in Lancashire; and there may have been others unknown to me.
Having had no opportunities of studying the habits of the bird myself, I must refer to the writings of those who have been more fortunately placed.
"During the past summer," says Mr. Hewitson, in a note to myself, " I noticed the bird wherever I went in Switzerland, on the mountain-passes on both sides and at the top of the Gemini, in the Canton Valais, and on the Righi.
"In former visits I saw it about the cathedral at Berne only.
"There I have many a time watched its glorious flight, and witnessed how superior it is in speed to the Common Swift.
"Whilst the latter species sweeps round you and below the promenade on which you stand, this bird pursues his wonderful flight high in the air."
Badly states that it is quite as common in the rocky portions of Savoy during the months of summer as it is in Switzerland and the Tyrol, that it arrives there from the 15th to the 20th of April, and that it feeds exclusively upon insects which it captures as it skims along with astonishing rapidity over bushes, trees, ditches, and the surface of the water into which it occasionally dips to secure its prey.
It commences the duty of incubation about the end of May or beginning of June.
Both sexes engage in the construction of the nest, which is usually placed in a nearly always inaccessible cleft of a rock, but occasionally among ruins or in a building situated on some mountainous ridge, and also under the stones on the roofs of the chalets.
It is externally composed of small sticks and roots, intermingled with which are pieces of straw, which they seize with such address while skimming over the ground that the action is scarcely perceptible.
The interior is lined with the catkins of poplars, the down of flowers, etc. which they seize in a similar manner or when blown about in the air, the whole being cemented together with the bird’s glutinous saliva.
The eggs are two or three in number, and of a pure white.
"The Alpine Swift,"' says the Rev. H. Tristram, "though very abundant, is rather a local bird in the Holy Land, and only a summer migrant.
"The first time we noticed it was at daybreak, on February 12th, when, camped outside the walls of Jerusalem, we saw large flocks passing with amazing rapidity, at a great height, towards the north.
"A few days afterwards, we noticed several of these birds among the Hills of Benjamin, disporting themselves, and often descending to the ground.
"They were probably preparing to breed in some of the deep ravines which run down towards the Jordan.
"From that time, throughout the summer, we rarely lost sight of this noble bird.
"The Wady Hamam, opening into the plain of Gennesaret, was a favourite resort of large flocks, which bred in the fissures of the stupendous cliffs, hopelessly beyond the reach of the most ardent rock-climber and nester.
"From their habit of selecting chinks under the overhanging ledges, it was impossible, even with the aid of ropes, to reach their holes; and could they have been attained, the pick and chisel must have been applied indefatigably to reach many of the nests.
"About daybreak, they might be seen dashing in long lines, with lightning speed, down the ravine, and exercising themselves over the plain.
"At this time in the morning, we were able occasionally to secure a specimen, but very soon they began to rise higher and higher, mingled with numbers of two other species, till in the depth of that dark, blue, cloudless sky they were at last lost even to the keenest sight.
"Towards evening they began to descend, flying lower than either of their associates, sometimes sweeping close to the ground, and dashing past us with bewildering swiftness.
"The sharp, grating sound of the whirr of their wings struck the ear for a moment , but the eye could scarcely follow them. However, as their flight was always remarkably straight, we were able to secure several specimens as they passed us.
"The motion of their long sharp wings was scarcely perceptible.
"Near Safed we found a colony breeding In a much more accessible position, evidently having young in the middle of May.
"We obtained several specimens, but had neither time nor appliances to attempt their nests.
"Once only did we find this swift breeding near the ground.
"On the 2nd of May we had climhed to the summit of Mount Gilead, overlooking the deep Jordan valley from the east side, one of the grandest panoramic views in Palestine.
"After standing for some time on a projecting platform of rock, which forms the western brow of the mountain, we descended to examine the face of the cliff, and discovered three large and partly artificial caves immediately below us.
"They were a mass of fossilized ammonites; and, while hammering at these, in one of the caves out flew two Alpine Swifts, whose nest we soon discovered in a crevice about six feet above the floor of the cavern.
"The chink, which was about three inches in perpendicular diameter, was contracted by a plastering of very hard mud, which cost us some labour to work out.
"Inside, the cavity enlarged as it descended, and, after scooping away the clay and portions of the rock, I was at length able to touch the two eggs with the tips of my fingers, but was unable to remove them.
"This was the only instance in which we observed the species breeding not in large colonies.
"Their roosting places are few, but what matters this to a bird that can traverse the whole extent of the Holy Land in an hour?
"The bird does not appear to resort much to the Hermon or the Lebanon, preferring the far more precipitous though lower cliffs which line the ravines running down to the Ghor.
"One other nesting-place we noticed, in a spot certainly selected with a view to the picturesque.
"Just above Ifka where the ground is strewn with the marble shafts of the famed temple of Venus, at Adonis, the classic stream of the Adonis bursts, full-grown at birth, in a prodigious volume, from the foot of a shallow cave under a lofty precipice.
"Here, on the 18th of June, a colony of Alpine Swifts were busily engaged in feeding their young.”
"The scream of this bird is much louder than that of the common Swift, and quite as harsh.
"It appears less reluctant than the common species to descend to the ground."
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