(1780) Ichthyophaga ichthyaetus ichthyaetus.
THE LARGE GREY-HEADED FISHING-EAGLE.
Falco ichthyaetus Horsf., Trans. Linn. Soc, xiii, p. 136 (1821) (Java). Polioaetus ichthyaetus. Blanf. & Oates, iii, p. 370 (part.).
Vernacular names. Madhuya (Hind.); Machmoral (Beng.); Na-Daoling gadeba (Cachari).
Description. Whole head and neck grey, tinged ashy, the shafts pale in old birds; crown darker and more brown except in the oldest birds; upper back brown, darkening on the wings, lower back, rump and upper tail-coverts; primaries still darker with a plum tinge on the upper aspect; tail white with a dark brown band across the terminal quarter, the extreme tip whitish; breast and anterior flanks brown, lighter than the back and generally rather reddish, occasionally grey-brown; abdomen, posterior flanks, vent, thigh- and under tail-coverts white.
Colours of soft parts. Iris bright golden yellow, paler yellow in young birds, mottled with brown or all brown in quite young birds, blue-brown' in nestlings ; bill dark horny-brown, the base bluish-plumbeous ; the cere brown; legs and feet china-white to dull pale yellowish-grey, claws black.
Measurements. Wing 450 (exceptional) to 515 mm.; tail 248 to 280 mm. ; tarsus 92 to 100 mm.; culmen 47 to 54 mm.
Young birds have the chin, throat and sides of the head grey; the rest of the upper parts dark brown, the head and neck streaked with whitish, the upper parts edged with greyish or fulvous-white; the white of the tail heavily mottled with brown; bases of primaries mottled and barred with white; breast and flanks pale brown, broadly streaked with white and the white parts more or less freckled with light brown.
Distribution. All India except Sind and North-West of Delhi; Assam, Burma, Malay Peninsula and islands East to the Celebes, Java and the Philippines.
Nidification. This Eagle breeds November to February, whilst Bingham took eggs on the 3rd March on the Thoungyeen River in Lower Burma. It is a very common bird in Assam and in many parts of Burma, almost invariably building its nest, a huge structure of branches which it occupies year after year, on a tree directly on a river-bank. This may be quite a small stream or a big river. Sometimes there is no lining, sometimes one of grass and rubbish. In Bengal it not unusually breeds on trees near large tanks or swamps and Jerdon speaks of finding a colony of these birds in Rajmahal, near the Ganges. The eggs number two to four and are pure white, though nearly always much stained; in shape they are proportionately longer than those of the preceding species. Twenty eggs average 68.6 x 51.9 mm.: maxima 70.0 x 51.9 and 69.4 x 54.5 mm. ; minima 59.8 x 50.6 and 66.3 x 50.0 mm. It seems to be a cowardly bird and seldom makes the slightest protest against the robbing of its nest.
Habits. This Eagle is one which seems to require woods as well as water and spends most of the day perched on some tree watching for fish, upon which it swoops with great speed and accuracy. In the rivers near the base of the hills Mahseer often bask by the edges and I have often seen this Eagle seize them. We once picked up one such fish of which the remains were over 12 lbs. This had evidently been seized from a pool with a shelving bank close by and thence dragged into the grass alongside. It will also eat carrion, reptiles and I have seen remains of jungle-fowl, squirrels and chickens near its nest. It has a very loud, deep call, which is not unmusical when heard in wilder country.
* Riley has shown (Proc. U.S. Nat. MUS., vol. lxiv, p. 43; ibid., Richmond, vol. xxvi, p. 492, 1903) that the proper name for this genus is Ichthyophaga) antedating Kaup's name Polioaetus by four years.