(1783) Ichthyophaga humilis plumbeus.
THE HIMALAYAN GREY-HEADED FISHING-EAGLE.
Polioaetus plumbeus Jerdon, Ibis, p. 336 (1871) (N.W. Himalayas). Polioaetus humilis. Blanf. & Oates, iii, p. 371 (part.).
Vernacular names. Na-Daoling-kashiba (Cachari).
Description. Similar to the preceding bird but larger.
Colours of soft parts as in I. ichthyaetus.
Measurements. Wing 435 to 495 mm.; tail 223 to 248 mm.; tarsus 78 to 91 mm.; culmen 40 to 46 mm.
Distribution. Sub-Himalayas from Kuman and Kashmir to Eastern Assam and Upper Burma. In Winter it has occurred as far South as Lucknow and wanders into the plains below the hills.
Nidification. This Eagle breeds all along the Himalayas from the foot-hills a few hundred feet high up to 5,000 feet, nearly always placing its nest in high trees on river-banks. In Assam the nests were always on forest-trees and this is the rule elsewhere, but occasionally one may be seen on solitary trees standing in cultivation or grass-land and this seems not uncommon in Kashmir. The nests are quite typical of the genus and are resorted to for many successive years, being repaired and added to until they are of very great size. The breeding-season varies from January to April, March and April being the two chief egg-laying months. The eggs, two or three in number, only vary from those of I. i. ichthyaetus in being smaller. Twenty average 64.6 x 20.1 mm.: maxima 70.6 X 53.0 mm.; minima 60.2 x 46.6 mm.
Habits, Except that this bird keeps almost entirely to the hills its habits are similar to those of the Large Grey-headed Fishing-Eagle. In Assam and Burma it is more definitely a forest- bird. The haunts of the two eagles overlap and I have taken the nest of this Eagle on the Diyung River in North Cachar, two days' journey by boat below where I have taken nest and eggs of its larger cousin. This Eagle is sometimes extremely noisy on moonlight nights during the breeding-season.