The Zoologist/3rd series, vol 1 (1877)/Issue 1/On the Occurence for the First Time in England of the American Red-breasted Thrush (''Turdus migratorius'')

by J.E. Harting ("the Editor")

 

ON THE OCCURRENCE FOR THE FIRST TIME IN
ENGLAND OF THE AMERICAN RED-BREASTED
THRUSH (TURDUS MIGRATORIUS).

By the Editor.

 

It is not a little remarkable that most of the specimens of North American birds which are recorded to have been found in Europe were taken in England. According to Professor Spencer Baird this has happened in fifty out of sixty-nine instances, and in nearly every case these specimens belonged to species which are abundant during summer in New England and the Eastern Provinces of British America. This computation, however, was made ten years ago,^[1] since which time the increased attention paid to Ornithology has resulted in the detection in Great Britain of several North American birds which had not been previously observed here, as well as many fresh instances of the appearance of species which had been already noted as occasional visitants to this country.

On referring to my 'Handbook of British Birds' (Introd. pp. x., xi.), I find that I had noted at the date of its publication, in 1872, the reported occurrence in the British Islands of 212 North American birds belonging to 42 different species. Omitting a few of these which have proved to be of doubtful authenticity, but adding some that I had overlooked, and a few others that have since occurred, we have in round numbers about 220 instances of the occasional appearance in Great Britain of North American birds. Of the forty-two species above referred to, five have been birds of prey, fourteen Passeres and Picariæ, one Columba, fourteen Grallatores, and eight Natatores.

I have now to add another to the list of passerine birds, in the shape of the American Migratory Thrush (Turdus migratorius), familiarly known as the American Robin.

In the month of September last I received a letter from Lieut. Charles Pope, of the 24th Regt., then stationed at Dover, in which he informed me that a friend of his had in his possession, alive, a remarkably coloured Thrush which he was unable to identify. It had been observed to fly in from the sea in a very exhausted state on a wet windy day during the previous month of April (or May, he was not sure which), and perching upon the first resting-place which presented itself, the balcony of a house facing the sea at Dover, had suffered itself to be frightened in through an open window and eventually caught. It lived in a small wicker-cage from April until September, when I first heard of it, and although the plumage became much soiled by confinement, it remained in good health.

From a description and sketch which Lieut. Pope forwarded, I had no doubt from the first that the bird was the North American Red-breasted Thrush, but it was not until two months later that I was enabled to pronounce with certainty upon the species. Being unable to refer to any of the works on American Ornithology to which I had referred him, Lieut. Pope prevailed upon his friend to forward the bird to me in London, and I duly received it on the 6th November last. My surmise was correct: it was undoubtedly Turdus migratorius.

With the Secretary's permission, I at once placed it in the Western Aviary in the Zoological Society's Gardens, where it may still be seen in good health, and in much improved plumage.

Now, how did this bird get to Dover? On my mentioning the circumstances of its capture to Mr. A.D. Bartlett, whose long experience as Superintendent of the Zoological Society's Gardens gives weight to his opinion in such matters, he was inclined to believe that it had escaped from some homeward-bound vessel in the Channel, and had made for the nearest land; a view which he thought was strengthened by the fact that the bird when he received it was very tame.

In this I do not quite concur, for I imagine that most homeward-bound vessels from New York return to Liverpool, and not viâ Dover; while the bird's tameness is easily accounted for by the fact that when Mr. Bartlett received it into his care it had already been in captivity for about six months. I am thus disposed to regard this as a genuine case of involuntary immigration.

Many such cases are already on record, and although this particular species is not known with certainty to have occurred here before, it has been met with on more than one occasion on the European continent, and, from its migratory habits, is just one of those birds which one would naturally expect now and then to arrive.

To account for the appearance of North American birds in this country is not so easy. I was at one time inclined to believe that the majority of them must find their way here from Greenland viâ Iceland,^[2] but the investigations of Professor Spencer Baird have led me to alter this opinion, and to concur for the present in his own view that their appearance here is due principally, if not entirely, to the agency of the winds at the period of their migrations. Prof Baird's remarks on this subject are so extremely interesting and at the same time so instructive, that they may be here appropriately quoted. After some pertinent observations on zoological geography and the general principles of distribution to which he has been led by an examination of the large collection of specimens in the Museum of the Smithsonian Institution, he proceeds to deal in detail with the migration of North American birds, and referring to the species which are reported to have occurred in England, he says:—

"Birds of North America rarely, if ever, reach England from Greenland by direct spontaneous migration by way of Iceland, as shown by the fact that only three of the American birds occurring in Greenland are found in Iceland, and that few of the American species observed in Europe are found in Greenland at all. Most specimens of American birds recorded as found in Europe were taken in England (about fifty out of sixty-nine), some of them in Heligoland, very few on the Continent (land-birds in only five instances). In nearly all cases these specimens belonged to species abundant during summer in New England and the Eastern Provinces of British America. In a great majority of cases the occurrence of American birds in England, Heligoland, and the Bermudas has been in the autumnal months. The clue to these peculiarities attending the interchange of species of the two continents will be found in the study of the laws of the winds of the northern hemisphere, as developed by Prof. Henry and Prof. Coffin. These gentlemen have shown that 'the resultant motion of the surface atmosphere, between latitudes 32° and 58° in North America, is from the west, the belt being twenty degrees wide, and its greatest intensity in the latitude of 45°. This, however, must oscillate north and south at different seasons of the year with the varying declination of the sun. South of this belt, in Georgia, Louisiana, &c., the country is influenced, at certain seasons of the year, by the north-east trade winds, and north of the same belt by the polar winds, which, on account of the rotation of the earth, tend to take a direction toward the west. It must be recollected that the westerly direction of the belt here spoken of is principally the resultant of the south-westerly and north-westerly winds alternately predominating during the year.'^[3]

"From these considerations and facts, therefore, we are entitled to conclude that the transfer of American birds to Europe, is principally, if not entirely, by the agency of the winds, in seizing them during the period of their migration (the autumnal especially), when they follow the coast, or cross its curves, often at a considerable distance from land, or a great height above it. Carried off, away out to sea, mainly from about the latitude of 45° (the line of greatest intensity of the winds), the first land they can make is that of England, whence the fact that most of the species have occurred in the British Islands as well as Heligoland, equally well fitted to attract stragglers and furnish them a resting-place."

In view of these observations from so competent an authority, it is not unlikely that the bird which forms the subject of this notice may have found its way to this country without the agency of man, and if this be so it deserves to be placed in the annually increasing catalogue of "Rarer British Birds."

 

1. See "The Distribution and Migrations of North American Birds," by Spencer F. Baird, in the 'American Journal of Science and Arts' (vol. xli., January, March, and May, 1866). Reprinted in 'The Ibis,' 1867, pp. 257–293.
2. In support of this view, it may be observed that out of the forty-two species of North American birds which are stated to have occurred in this country, sixteen, on the authority of Professor Reinhardt, have been found in Greenland.
3. See Prof. Henry's articles on Meteorology, 'Report of Commissioner of Patents for 1856," p. 489.