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| Despite being weak flyers, jays are capable of travelling long distances (picture: Ann Williams) |
Jays are mostly regarded as sedentary rather than migratory birds, but, in some years, there can be large irruptions - flocks arriving here in the UK from eastern Europe for no conspicuously obvious reason. In this paper, published in the January, 1883, edition of The Ibis journal, Lincolnshire ornithologist John Cordeaux explores the Jay-migration phenomenon with special reference to the records of his friend, Heinrich Gätke, who, for many years, monitored bird passage as witnessed on the island of Heligoland off the German coast.
Under such circumstances, the bird seems little capable of crossing any width of sea or of taking a long migratory flight.
The fact, however, remains beyond dispute that this seemingly weak and slow-flying bird is capable of long-sustained flights which will compare even with those of the swift-winged Woodcock and Grey Plover.
Great numbers of Jays, along with other migrants, crossed Heligoland with an east to west flight in October, 1876.
Heinrich Gätke's notes sent to me at that time are as follows: "Oct. 21. East, very strong. Jays, thousands passing the island; some landed, caught; coming, never ending.
"Oct. 22-23. East, strong. Jays, a great many still."
Since that date, and up to this year, Jays do not appear to have been observed at Heligoland.
Mr Gätke's subsequent, and almost continuous, notes make no mention of them.
Either the migration has passed some distance off the island or been carried on at such a height as to be beyond the ken of human vision.
But during the past autumn, Jays have again passed Heligoland in enormous numbers.
On October 8, Mr Gätke writes: "A perfect storm of Jays has passed over, and on both sides of the island, during the last three days.
Either the migration has passed some distance off the island or been carried on at such a height as to be beyond the ken of human vision.
But during the past autumn, Jays have again passed Heligoland in enormous numbers.
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| John Cordeaux - farm manager and ornithologist who lived on the outskirts of Grimsby |
"No one living has ever seen the like here.
"About fifty years ago, enormous numbers were caught here, but during my time only twice or thrice have they come."
It is noticeable that, in both these years, the migration of the Jay was in October, and continued over three days, and that it was carried on under the circumstances of a strong easterly gale.
The question then naturally arises, to whence and whither was this great "storm" of Jays (as Mr Gätke terms it) steering their course?
Seen then seventy miles from land off the mouth of the Elbe, moving from east to west in a strong easterly gale, continuous flock after flock, never deviating from their course which was straightforward, seemingly across the wide tossing waters of the North Sea, with one purpose animating all alike, the forsaking of their native forests for a long flight to the west.
Mr. Gatke has always maintained that autumn migration, as observed at Heligoland, does not run north and south, but from east to west, birds invariably coming from the eastward and passing westward.
The observations taken during late years on the migration of birds, as observed at lighthouses and light vessels, quite confirm the views of the veteran observer.
It is rarely that we find birds coming to our shores from any point north of east.
Migration is from east to west, or points south of east to north-easterly points.
This great passage of Jays across Heligoland points also to the correctness of his theory, for it could hardly have its origin in the north, the whole of Scandinavia failing to supply the stream for more than a few hours.
It is reasonable, therefore, to suppose that they came from Eastern Europe across Germany, from the immense forest area between the Oder to beyond the Vistula, and probably much further east than this to the confines of Eastern Europe.
That the area covered by this flight was very great we may well judge from the fact that the stream was three days in passing.
Whether the first impulse to move began at the extreme east or west of the range, extending backward or forward, we have unfortunately no means of knowing.
It will be interesting to learn if any great flight of Jays, corresponding in any degree with the thousands that crossed Heligoland, have been observed anywhere on the English coast, or any considerable increase in the ordinary number frequenting our woodlands.
Previous to receiving Mr Gätke's letter, I had made a note of the number seen in some small plantations, but certainly not exceeding double what we might expect to see under any circumstances.
In his Birds of Norfolk, Mr. H. Stevenson conjectures that the Norfolk Jays receive at times considerable accessions to their number in the autumn.
So far as I am aware, there is no direct evidence of the fact except the statement, as given by Messrs. R. Sheppard and W. Whitear (A Catalogue of Norfolk and Suffolk Birds, 1826) to the effect that "some years ago, as two gentlemen were sporting at Tunstall in Suffolk, a distance of about five miles from the sea, they observed an extraordinary flight of Jays passing in a single line from seaward to the interior.
"This line extended further than the eye could reach, and must have consisted of some thousands."
"Several of them were killed as they passed, but the firing at them did not occasion the rest to deviate from their line of flight."
It may be that the Jays seen crossing Heligoland passed southward along the European coastline, as we know is the case with many birds which regularly cross that island in large numbers, and which rarely turn up on our own coast, except perhaps as solitary examples.
Be this as it may, however, this migration in such enormous numbers is a wonderful and striking phenomenon, and supplies cause for much conjecture - conjecture as to the how and why of this simultaneous movement.
Whether a mere normal phenomenon, which, under certain conditions of wind and weather, is at long intervals brought within the notice of the Heligolanders, or a something out of the ordinary range of migration due to a scarcity of food or some other cause which long patient waiting and extended observation alone can determine.
It is noticeable that, in both these years, the migration of the Jay was in October, and continued over three days, and that it was carried on under the circumstances of a strong easterly gale.
The question then naturally arises, to whence and whither was this great "storm" of Jays (as Mr Gätke terms it) steering their course?
Seen then seventy miles from land off the mouth of the Elbe, moving from east to west in a strong easterly gale, continuous flock after flock, never deviating from their course which was straightforward, seemingly across the wide tossing waters of the North Sea, with one purpose animating all alike, the forsaking of their native forests for a long flight to the west.
Mr. Gatke has always maintained that autumn migration, as observed at Heligoland, does not run north and south, but from east to west, birds invariably coming from the eastward and passing westward.
The observations taken during late years on the migration of birds, as observed at lighthouses and light vessels, quite confirm the views of the veteran observer.
It is rarely that we find birds coming to our shores from any point north of east.
Migration is from east to west, or points south of east to north-easterly points.
This great passage of Jays across Heligoland points also to the correctness of his theory, for it could hardly have its origin in the north, the whole of Scandinavia failing to supply the stream for more than a few hours.
It is reasonable, therefore, to suppose that they came from Eastern Europe across Germany, from the immense forest area between the Oder to beyond the Vistula, and probably much further east than this to the confines of Eastern Europe.
That the area covered by this flight was very great we may well judge from the fact that the stream was three days in passing.
Whether the first impulse to move began at the extreme east or west of the range, extending backward or forward, we have unfortunately no means of knowing.
It will be interesting to learn if any great flight of Jays, corresponding in any degree with the thousands that crossed Heligoland, have been observed anywhere on the English coast, or any considerable increase in the ordinary number frequenting our woodlands.
Previous to receiving Mr Gätke's letter, I had made a note of the number seen in some small plantations, but certainly not exceeding double what we might expect to see under any circumstances.
In his Birds of Norfolk, Mr. H. Stevenson conjectures that the Norfolk Jays receive at times considerable accessions to their number in the autumn.
So far as I am aware, there is no direct evidence of the fact except the statement, as given by Messrs. R. Sheppard and W. Whitear (A Catalogue of Norfolk and Suffolk Birds, 1826) to the effect that "some years ago, as two gentlemen were sporting at Tunstall in Suffolk, a distance of about five miles from the sea, they observed an extraordinary flight of Jays passing in a single line from seaward to the interior.
"This line extended further than the eye could reach, and must have consisted of some thousands."
"Several of them were killed as they passed, but the firing at them did not occasion the rest to deviate from their line of flight."
It may be that the Jays seen crossing Heligoland passed southward along the European coastline, as we know is the case with many birds which regularly cross that island in large numbers, and which rarely turn up on our own coast, except perhaps as solitary examples.
Be this as it may, however, this migration in such enormous numbers is a wonderful and striking phenomenon, and supplies cause for much conjecture - conjecture as to the how and why of this simultaneous movement.
Whether a mere normal phenomenon, which, under certain conditions of wind and weather, is at long intervals brought within the notice of the Heligolanders, or a something out of the ordinary range of migration due to a scarcity of food or some other cause which long patient waiting and extended observation alone can determine.
* Interested in the writings of John Cordeaux? The title below is now available (price £2) as an e-book.
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