(571) Turdus boulboul (Lath.).
The GREY-winged Blackbird.
Turdus boulboul, Fauna B. I., Birds, 2nd ed. vol. ii, p. 130.
This Blackbird has a very wide range, over the greater part of which it is very common. In and about Murree it breeds in great numbers between 6,000 and 8,000 feet and, in smaller numbers, up to 10,000 feet. Dodsworth and Jones took many nests in the Simla States between 6,500 and 7,500 feet ; Osmaston obtained its nest at Chakrata at about the same elevation. In Nepal it was found breeding by Hodgson and, in the East of that State, Stevens took its nest as low down as 4,000 feet, but records that it also occurs up to 9,000 feet in Summer, whilst in Sikkim Gammie records it breeding at 4,000 and 5,000 feet, and Stevens at Gopaldhara between 4,500 and 6,500 feet. Though it occurs East to the Hills North of Sibsagar, I have no records of it breeding there, but I was surprised to find its nest South of the Brahma¬pootra on several occasions in the North Cachar Hills in hot, humid forests at 4.000 and 4.500 feet elevation.
It is a forest bird that, except in the Assam Hills, keeps to rather open forest or to the edges of, and glades in, the denser parts.
The site chosen for the nest varies greatly. Perhaps 50 per cent, of nests are built in small trees, often Oaks, at heights of, and under, about 25 feet. It is in such cases built either in a stout fork, on a bough at its junction with the trunk, or on some moss- covered excrescence, concealment, apparently, being a matter of little import. At other times it is built in banks in some natural hollow or among the roots of some large tree. A favourite position with this Thrush, as with many others, is in among the roots of some fallen tree, tucked away in a hollow from which the earth has fallen, and supported by the masses of exposed roots. Gammie, writing of the Grey-winged Blackbird in Sikkim, says that for the nest “the favourite position is, at the height of 20 or 30 feet, tight on the summit of a stump of a Ficus-tree, from which the Bhutias have cut the top, and pollarded for the sake of the leaves for their milch cows. The nest is kept in its place, and concealed, by the upright shoots springing away from below the stump end ; the bottom of the nest fits the end of the stem."
The nest is the usual bulky cup, covered outside with moss and constructed internally of grass-roots and leaves, with a lining of finer roots or, more often, grass. Sometimes mud is used as an inner lining, but this is often dispensed with. Gammie took one nest on the 20th May in the Government Cinchona Reserve, of which he says : “No mud at all had been used in the construc¬tion of the nest” ; whereas of another he says, “a neat compact shell is first made of twigs and moss, then a good coating of mud and, finally, a thick lining of fibry roots. Externally it measures about 6 inches across by 3.2 in height ; internally the cavity is 3.5 inches in diameter by 2 in depth.” Hodgson describes the nest as without a mud lining, but Sir E. Buck took one with “a layer of mud between external and internal layers.”
The normal breeding season is May and June but, whilst a few birds breed on into July, some commence much earlier, Stevens having taken one nest with fresh eggs on the 8th March at Polpoti in Nepal. Home took one nest with two eggs as late as the 8th August near Almorah.
Three or four eggs are laid, there being no record of any clutch of five or of two which showed signs of incubation.
On one occasion Dodsworth took two fresh eggs from a nest on the 9th of June and on the 18th took two others which were considerably incubated. These, however, were undoubtedly just a normal clutch of four.
The eggs could not, I think, be distinguished from those of the preceding bird but they show a good deal more variation. In my series I have a set of four so closely marked with deep brownish-red that they appear to be almost unicoloured mahogany ; another set has a pinkish stone ground, marbled all over with chestnut- brown primary and lavender-pink secondary blotches. In yet a third set the ground-colour is a distinct green, heavily blotched with dark reddish-brown, dense and coalescing at the larger end and then decreasing numerically towards the small end. Most eggs are like handsomely blotched eggs of the Blackbird, generally of the reddish type, whilst I have seen no eggs of the more Thrush¬like character of the southern birds’ eggs.
In shape they are rather long ovals, sometimes slightly pointed, and broad ovals are exceptional. The texture is fairly fine and close and most eggs have a slight gloss.
Fifty eggs average 29.0 x 20.9 mm. : maxima 33.9 x 23.3 mm. ; minima 24.0 x 21.4 and 27.2 x 19.9 mm.
Turdus rubrocanus rubrocanus. The Western Grey-headed Thrush.
(Baisaran, Kashmir, 8,000 ft., 20.5.32.)
This Thrush is said to be extremely wary, slipping off the nest before the intruder is near enough to see it but, in N. Cachar, I found that, when disturbed, both male and female soon returned to the nest and it was easy to trap the female or shoot the male for purposes of identification. The female alone carries on incu¬bation, so far as is known at present, but both birds share in the work of building the nest.
571. Turdus boulboul
(571) Turdus boulboul (Lath.).