(1747) Aquila heliaca heliaca
THE IMPERIAL EAGLE,
Aquila heliaca Savigny, Descrip. Egypte, Ois., p. 82 (1809) (Upper Egypt); Blanr. & Oates, iii, p. 334.
Vernacular names. Jumiz, Jumbiz, Barra Jumiz, Satangal (Hind.); Frus (Beng.).
Description. The lanceolate feathers of the crown and sides of the head, nape, hind-neck and sides of the neck pale tawny-buff, the lores deeper in tint and the forehead more or less streaked with black; feathers of the hind-neck with black or dark rufous centres ; tail tipped whitish with a broad subterminal band of black, remainder of feathers with alternate mottled bands of grey and dark brown ; some of the scapulars pure white ; remainder of plumage deep blackish-brown ; in some specimens, probably not very old, the wing-feathers and dark scapulars are edged with dull buff; vent and under tail-coverts dull buff.
Colours of soft parts. Iris light hazel or hazel; young birds duller and browner ; bill bluish-horny tipped blackish; cere yellow to greenish-yellow ; legs and feet dull yellow.
Measurements. Indian specimens: wing, 575 to 600 mm., 605 to 630 mm.; tail 253 to 270 mm.; tarsus about 91 to 95 mm.; culmen about, 54 to 55 mm., 60 to 66 mm.; hind claw, 35 to 36 mm., 38 to 43 mm.
Young birds have the whole upper plumage tawny-buff, the lower back, rump and upper tail-coverts almost immaculate, the remaining feathers with broad brown edges; wing-quills blackish, paling to buffy-brown on the innermost secondaries and all but the first three primaries tipped pale buff; tail dull rufous-brown, the tip pale rufous; lower surface pale rufous-buff, the throat faintly, the breast, flanks and abdomen boldly edged with dark rufous-brown.
In a later stage the dark markings of the lower surface become blacker and more extensive, the tail shows mottlings at the base and the wing-coverts and scapulars less buff.
The fully adult, almost black plumage, with many conspicuous white scapulars, probably takes about six years to acquire.
Distribution. South-East Europe; Central Asia to Mongolia, South to the Himalayas and in Winter further South again to the Deccan and as far East as Earidpore in Eastern Bengal.
Nidification. The Imperial Eagle breeds throughout its area to the mountains of Northern India. Within our limits but very few nests have been found which can with certainty be identified but there are authentic nests and eggs from Kashmir, Dehra Ismail Khan and from the Baluchistan-Sind Hills. It is a tree-breeder, making a large nest of sticks and branches lined with smaller branches or with no lining at all. The eggs, two in number, vary greatly in colour but as a series are very poorly and weakly marked. The ground is white or greyish-white, in some unspotted or almost so, in others weakly spotted and smudged with grey-brown or light reddish, whilst in a few only are there handsome markings of red-brown or deep reddish. Jourdain gives the average of twenty-three European eggs as 73.3 x 57.6 mm.: maxima 76.4 x 59.0 and 74.6 x 61.7 mm.; minima 67.2 X 55.4 and 68.5 x 52.3 mm. Six Indian eggs in my collection average only 70.1 x 54.0 mm.
In Europe the breeding-season is April and May but in India November to January.
Habits. The Imperial Eagle is a bird of the plains and the lower hills. In Kashmir it appears to he found up to some 7,000 feet but breeds much lower than this, though authentic records are scarce. It is very inferior in all ways to the Golden Eagle, a poorer flier, a weaker, less bold bird and often an eater of carrion. It kills small mammals, birds and reptiles but is of a very sluggish disposition, spending much of its time perching on trees or rocks or even on the ground. It has often been compared with a Buzzard rather than with other Eagles.