(1779) Haliaetus leucoryphus (Pall.).
THE WHITE-TAILED, or PALLAS'S, FISHING-EAGLE.
Haliaetus leucoryphus, Fauna B. I., Birds, 2nd ed, vol. v, p. 112.
This Eagle, formerly known as Pallas’s Sea-Eagle—a misnomer, as it by no means keeps to the sea-coast—is distributed over the whole of Northern India from the Himalayas South to Sind, Punjab, United Provinces, Bengal and Orissa. In Burma it extends from the North to Southern Pegu. In the Himalayas it breeds commonly up to an altitude of some 6,000 feet, possibly much higher, as Ludlow says that it is common on the larger lakes in, Tibet, such as Bhamtso and Kalo Tso, in Summer, occasionally at an elevation of 12,000¬-14,000 feet.
It is the moat common of all our big Indian Eagles. Hume says (‘Nests and Eggs,’ vol. iii, p. 163) : “In Upper India I do not know a single large jheel which retains water in it as late as February where a pair of this species does not breed ; and all down the Jumna, Ganges, Charabul, Indus, Chenab, Jhelum and Sutledge, wherever I have been I have invariably met with at least one pair every 3 or 4 miles, and in particular localities every half mile.”
The same may also he said of the rivers of Eastern Bengal and Assam, the Megna, Hugli, Barak, Brahmapootra etc., while in the huge lakes, swamps and morasses of the Sunderbands the nests are constant and conspicuous sights wherever one goes. They never breed far from water of some kind and, in Assam and Eastern Bengal at all events, the favourite sites for building are in the great trees nearly always to be found in or on the outskirts of some small fishing village. I have seen their nest in trees in the middle of bazaars, where the birds have fed their young or incubated their eggs with perfect content in a babel of sound above which their own raucous voices passed almost unnoticed. In the district of Sylhet a pair chose for their home a single huge Peepul growing by a steamer-ghat on the Barak River, paying not the slightest attention to the whistles and hootings of the steamers or to the turmoil of loading and unloading going on almost under the nest itself.
Like that of so many other Eagles, the nest is occupied year after year. It is big even when first made, a new nest measuring anything up to 4 feet in diameter by a foot or more in depth but, as season succeeds season, it may be added to until it is nearly half as wide again and three or four times as deep, I have never seen any lining in the nest but, sometimes, it certainly, adds grass, finer twigs, sticks and green leaves to the hollow in which the eggs lie. The sticks used for the body of the nest are often of considerable size, in some instances as much as 3 to 4 feet long and 2 to 3 inches thick, which must weigh several pounds.
Big trees are generally chosen for the nests and generally such as have dense foliage, but Doig, in Sind, obtained nests which were built on trees growing in the middle of swamps, usually decayed and devoid of foliage. The nests are constructed on large houghs as near as possible to the tops of the trees but not always at great heights. I have seen them on Mango and Banyan-trees 30 feet from the ground and, on the other hand, on Peepul, Bombax and other huge trees at all heights from 40 to nearly 100 feet up.
Everywhere the breeding season is the same, November, December and January, but eggs have been taken from the 10th October to the end of February.
The usual clutch of eggs is three, but two only are often laid and occasionally four. They are white, unless sullied in the nest, the texture coarse, but the surface is generally rather smooth, some¬times quite smooth, though never glossy.
Sixty eggs average 69.7 x 55.1 mm. : maxima 76.8 x 57.9 mm. ; minima 63.5 x 53.5 and 69.0 x 50.0 mm.
This is one of the few of our big Indian Raptores of which we really have ft life-history, most of it embodied in Hume’s fascinating account:—“I do not think that this species ever takes possession, of other birds’ nests. It either builds a new nest for itself, or repairs one formerly belonging to it, even though this may in the interim have been usurped by Otogyps calvus or Ketupa ceylonensis, both much addicted to annexing the poor Fishing-Eagle’s laboriously constructed nest. I say laboriously constructed, because I once saw a young pair constantly occupied for a full month building a nest, which they were still at work finishing off when I left. Nothing can seem rougher or more rugged than their nest when finished, and yet out of every four sticks and branches that they brought they rejected and threw down at least three. Both birds brought materials, side by side the pair would work away, then apparently they would quarrel over the matter—there would be a great squealing — and one would fly away and sit sulky on some cliff point near at hand ; after a time the one left on the nest would go off in quest of materials. Immediately the other would drop softly on to the nest and be very busy (though what they did, except lift a stick and put it down in the same place, it was impossible, even with a good glass, to make out) till the absent bird returned, not in¬frequently with a fish instead of a stick.
“One curious point about these birds, unlike most Eagles, they do not always desert a plundered nest, I have twice taken single eggs out of nests and ten or twelve days later I found that a couple more eggs had been laid.”
This, of course, really meant that the birds had completed their laying, but there are several instances known in which the birds, having lost their first full clutch, have again laid, after a month or so, another full clutch in the same nest. Hutton describes how a pair of these Eagles defended their young ones so savagely that he had to fire at them, both birds repeatedly swooping at the man as he climbed the tree, collared a youngster and returned. Doig also says that once in Sind he came across a pair of Eagles who made some attempt to protect their young. In the very great number of cases in which I myself, Hume, and many others have taken egga or young the birds have flapped slowly away, making no sign of attack whatever.
Both parents share in the work of incubation, though possibly the male does less than the female ; on the other hand, when the young are first hatched the male does more of the catching fish etc. for their food than the female does.
Incubation lasts thirty days, possibly sometimes two days more or two days less. Eggs, a clutch of three, laid on 3rd, 5th and 7th December, after which the birds began to sit, hatched 5th and 6th January, and the birds remained in the nest until the 18th April, when they climbed out on to adjacent branches, beginning to attempt flights on the 20th, and flying well on the 23rd.
A curious incident came under my observation once when a pair of birds deserted their nest on a huge Simul-tree on the banks of the Brahmapootra, although it was some yards from the edge. In the spring floods the banks were washed away and the tree fell with a mighty crash into the river. What kind of instinct had warned the birds of the impending disaster ?
1779. Haliaetus leucoryphus
(1779) Haliaetus leucoryphus (Pall.).