1911 Encyclopædia Britannica/Sheld-drake

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SHELD-DRAKE, or, as commonly spelt in its contracted form, Sheldrake, a word whose derivation[1] has been much discussed, one of the most conspicuous birds of the duck tribe, Anatidae, called, however, in many parts of England the “Burrow-Duck” and in some districts by the almost obsolete name of “Bergander” (Du. Berg-eende, Ger. Bergente), a word used by Turner in 1544.

The sheldrake is the Anas tadorna[2] of Linnaeus, and the Tadorna cornuta of modern ornithology, a bird somewhat larger and of more upright stature than an ordinary duck, having its bill, with a basal fleshy protuberance (whence the specific term cornuta), pale red, the head and upper neck very dark glossy green, and beneath that a broad white collar, succeeded by a still broader belt of bright bay extending from the upper back across the upper breast. The outer scapulars, the primaries, a median abdominal stripe, which dilates at the vent, and a bar at the tip of the middle tail-quills are black; the inner secondaries and the lower tail-coverts are grey; and the speculum or wing-spot is a rich bronzed-green. The rest of the plumage is pure white, and the legs are flesh-coloured. There is little external difference between the sexes, the female being only somewhat smaller and less brightly coloured. The sheldrake frequents the sandy coasts of nearly the whole of Europe and North Africa, extending across Asia to India, China and Japan, generally keeping in pairs and sometimes penetrating to favourable inland localities. The nest is always made under cover, usually in a rabbit-hole among sand hills, and in the Frisian Islands the people supply this bird with artificial burrows, taking large toll of it in eggs and down.

T. radjah of Australia, Papuasia and the Moluccas almost equals the true sheldrake in its brightly contrasted plumage, but the head is white in both sexes. Barbary, south-eastern Europe, and Central Asia are inhabited by an allied species of more inland range and very different coloration, the T. casarca or Casarca rutila of ornithologists, the ruddy sheldrake of English authors—for it has several times strayed to the British Islands and the “Brahminy Duck” of Anglo-Indians, who find it resorting in winter, whether by pairs or by thousands, to their inland waters. This species is of an almost uniform bay colour all over, except the quill-feathers of the wings and tail, and (in the male) a ring round the neck, which are black, while the wing-coverts are white and the speculum shines with green and purple; the bill and legs are dark-coloured.[3] A species closely resembling the last, but with a grey head, C. cana, inhabits South Africa. In Australia occurs another species of more sombre colours, the C. tadornoides; and New Zealand is the home of another species, C. variegata, still less distinguished by bright hues. In the last two the plumage of the sexes differs not inconsiderably.

Sheldrakes will, if attention be paid to their wants, breed freely in captivity, crossing if opportunity be given them with other species, and an incident therewith connected possesses an importance hardly to be overrated by the philosophical naturalist. In the Zoological Society's gardens in London in the spring of 1859 a male of T. cornuta mated with a female of C. cana, and, as will have been inferred from what has been before stated, these two species differ greatly in the colouring of their plumage. The young of their union, however, presented an appearance wholly unlike that of either parent, and an appearance which can hardly be said, as has been said (P.Z.S., 1859, p. 442), to be “a curious combination of the colours of the two.” Both sexes of this hybrid have been admirably portrayed by J. Wolf; and, strange to say, when these figures are compared with equally faithful portraits by the same master of the Australian and New Zealand species, C. tadornoides and C. variegata, it will at once be seen that the hybrids present an appearance almost midway between the two species last named-species which certainly had nothing to do with their production.[4]

The genera Tadorna and Casarca, as shown by the tracheal characters and coloration, are most nearly related to Chenalopex, containing the bird so well known as the Egyptian goose, C. aegyptiaca, and an allied species, C. jubata, from South America. For the same reason the genus Plectropterus, composed of the spur-winged geese of Africa, and perhaps the Australian Anseranas and the Indian and Ethiopian Sarcidiornis, also appear to belong to the same group, which should be reckoned rather to the Anatine than to the Anserine section of the Anatidae.  (A. N.) 

  1. Ray in 1674 (Engl. Words, p. 76) gave it from the local “sheld” ( = particoloured), which, applied to animals, as a horse or a cat, still survives in East Anglia. This opinion is not only suitable but is confirmed by the bird's Old Norsk name Skjöldungr, from Skjöldr, primarily a patch, and now commonly bestowed on a piebald horse, just as Skjalda (Cleasby's Icel. Dict., sub voce), from the same source, is a particoloured cow. But some scholars interpret Skjöldungr by the secondary meaning of Skjöldr, a shield, asserting that it refers to “the shield-like band across the breast” of the bird. If they be right the proper spelling of the English word would be “Shield-drake,” as some indeed have it. A third suggested meaning, from the Old Norsk Skjól, shelter, is philologically to be rejected, but, if true, would refer to the bird's habit, described in the text, of breeding under cover.
  2. This is the Latinized form of the French Tadorne, first published by Belon (1555), a word on which Littré throws no light except to state that it has a southern variant Tardone.
  3. Jerdon (B. India, iii. 793) tells of a Hindu belief that once upon a time two lovers were transformed into birds of this species, and that they or their descendants are condemned to pass the night on the opposite banks of a river, whence they unceasingly call to one another: “Chakwa, shall I come?” “No, Chakwi.” “Chakwi, shall I come?” “No, Chakwa.” As to how, in these circumstances, the race is perpetuated the legend is silent.
  4. It is further worthy of remark that the young of C. variegata when first hatched closely resemble those of C. rutila, and when the former assume their first plumage they resemble their father more than their mother (P.Z.S., 1866, p. 150).