by Greg Mayer

My Okinawan correspondent sends the following photograph of an apparently window-killed bird.

I thought immediately, “a thrush”, noting the similarity in bill, body and leg shape to that of the familiar North American Robin (Turdus migratorius). I was also immediately reminded of the justly famous opening passage in Alfred Russel Wallace’s Island Life, in which, comparing the birds of Britain and Japan, he finds them remarkably similar:

WHEN an Englishman travels by the nearest sea-route from Great Britain to Northern Japan he passes by countries very unlike his own, both in aspect and natural productions. The sunny isles of the Mediterranean, the sands and date-palms of Egypt, the arid rocks of Aden, the cocoa groves of Ceylon, the tiger-haunted jungles of Malacca and Singapore, the fertile plains and volcanic peaks of Luzon, the forest-clad mountains of Formosa, and the bare hills of China, pass successively in review; till after a circuitous voyage of thirteen thousand miles he finds himself at Hakodadi in Japan. He is now separated from his starting-point by the whole width of Europe and Northern Asia, by an almost endless succession of plains and mountains, arid deserts or icy plateaux, yet when he visits the interior of the country he sees so many familiar natural objects that he can hardly help fancying he is close to his home. He finds the woods and fields tenanted by tits, hedge-sparrows, wrens, wagtails, larks, redbreasts, thrushes, buntings, and house-sparrows, some absolutely identical with our own feathered friends, others so closely resembling them that it requires a practised ornithologist to tell the difference. If he is fond of insects he notices many butterflies and a host of beetles which, though on close examination they are found to be distinct from ours, are yet of the same general aspect, and seem just what might be expected in any part of Europe. There are also of course many birds and insects which are quite new and peculiar, but these are by no means so numerous or conspicuous as to remove the general impression of a wonderful resemblance between the productions of such remote islands as Britain and Yesso.

(Perhaps inspired by Wallace, the Japanese ornithologist Masa Hachisuka once published a comparative list of the birds of Britain and Japan.) Wallace went on to contrast the remarkable similarities between the birds of these two distant archipelagos with the differences one finds when crossing the narrow strait between Bali and Lombok:

In the Malay Archipelago there are two islands, named Bali and Lombok, each about as large as Corsica, and separated by a strait only fifteen miles wide at its narrowest part. Yet these islands differ far more from each other in their birds and quadrupeds than do England and Japan. The birds of the one are extremely unlike those of the other, the difference being such as to strike even the most ordinary observer. Bali has red and green woodpeckers, barbets, weaver-birds, and black-and-white magpie-robins, none of which are found in Lombok, where, however, we find screaming cockatoos and friar-birds, and the strange mound-building megapodes, which are all equally unknown in Bali. Many of the kingfishers, crowshrikes, and other birds, though of the same general form, are of very distinct species; and though a considerable number of birds are the same in both islands the difference is none the less remarkable—as proving that mere distance is one of the least important of the causes which have determined the likeness or unlikeness in the animals of different countries.

Wallace, of course—in this and many other works—went on to explicate what the important causes of these disparities were, not the least of which are the evolutionary and geological histories of the organisms and land masses. (In the case of Bali and Lombok, the key factor has turned out to be that Bali is on the Asian continental shelf, and thus has been in frequent dry-land contact with the continental fauna, while Lombok is off the shelf, and has received its fauna over water by occasional means of transport.)

Like Wallace’s traveling Englishman, I too was struck by the great familiarity to me of this bird from the opposite side of the world. But while it was certainly a thrush, and almost certainly in the genus Turdus, I could not identify the species. I don’t have a Japanese or East Asian bird field guide, but checking some pictures on the internet, it seems most similar to T. pallidus, a winter visitor to Okinawa. Our deceased friend seems too white below, so I leave its species undetermined. Perhaps some reader will be able to identify it.

In addition to being a familiarly thrush-like bird, it was also, sadly, in a familiar posture: dead outside a glass door. Window-killed Swainson’s thrushes (Catharus ustulatus) are an all too familiar sight here in southeastern Wisconsin. My correspondent added about this bird, “Such a shame to see a dead bird, because they’re actually kind of rare to see. I blame the cats and Habu.” Habu are any of various pit vipers found in the Ryukyu Islands, which I thought were not common. I’ve queried my correspondent as to the relative abundance of cats and habu.

Hachisuka, M.U. 1925. A Comparative Hand List of the Birds of Japan and the British Isles. Cambridge University Press, Cambridge. (paperback published 2015)

Wallace, A.R. 1892. Island Life. 2nd ed. Macmillan, London. (at Wallace Online)