(603) Zoothera monticola Vigors.
THE LARGE BROWN THRUSH.
Zoothera monticola, Fauna B. I., Birds, 2nd ed. vol. ii, p. 166.
This fine Thrush is found in the Himalayas from the Sutlej Valley to Assam, both North and South of the Brahmapootra, Manipur and Chin Hills.
I found this bird breeding, though very rarely, in the North Cachar Hills between 3,000 and 6,000 feet. In the Khasia Hills it bred between 4,000 and 6,200 feet, some years being very rare, at others almost common in exactly the same forests. On the 30th May, 1908, Whymper took its nest in Kuman at about 7,000 feet ; on the 15th May, 1910, Venning obtained it breeding at Haka, about 6,000 feet ; A. E. Osmaston got a nest at 8,000 feet in Garhwal and it breeds also in the Simla Hills at about 7,000 feet.
The Large Brown Thrush is a very shy, skulking bird with a beauti¬ful mellow whistle which is much more often heard than the bird is seen. It keeps almost entirely to the deepest and most humid forest and, preferentially, to broken ground running up from streams or to ravines through which water runs more or less constantly. All the nests taken by myself have been close to running water of some kind, though never streams or other water sufficiently big to make a gap in the darkness of the forest. With one exception the nests I have seen in situ, or which have been recorded by other observers, have been on small trees or high boulders between 5 and 25 feet from the ground, very seldom over 15 feet. As a rule it is placed in a fork or on two or more interlacing horizontal boughs but, occasionally, on creepers or on some projecting mass of orchids or ferns on the trunk of a tree. The tree selected is nearly always one more or less covered with moss, which makes the large moss- covered nest look less conspicuous than would otherwise be the case. The one exception referred to was a nest placed against the face of a huge boulder, cuddled in among great wreaths of flowing moss and clumps of fern, much like our English Hart’s- tongue fern, completely screening it from view.
The nest itself is very big and often very shapeless, whilst at other times it is quite a well-shaped cup. The first nest I ever took was a mass of wet moss, much mixed with earth and leaves and with an inner cup of coarse roots, soft twigs and bits of stick and then the true lining of finer roots and fern-rachides. The base of this nest filled in the fork of two big boughs of a small tree and was nearly a foot across but the cup was only about 4 by 2 inches deep. Another nest was made of exactly the same materials but was a fairly neat cup outwardly 6 inches in diameter by 3.1/2 deep, with a well- finished cup about 4 inches across by 2.3/4 in depth.
Other nests were intermediate in shape but the materials hardly ever varied, though I have seen bracken, fern-fronds, a few broad grass-blades, weed-stems and creepers used in small quantities in addition to the materials enumerated. In all my self-taken nests moss has been the main material used but Venning describes one nest in which there was very little :—“It consisted of a large lump of earth for a basis, intermingled with sticks and fibres and with a little moss worked into the outside, the whole being scantily lined with whitish roots or fibres. It was 4 inches across the interior and 1.1/2 inches deep, but the whole nest was about one foot in dia¬meter.”
The breeding season is May and June and I have taken eggs from the 3rd May to the 7th July.
The usual full clutch of eggs is three, though four is not very un¬common and sometimes two only are incubated. The eggs are quite typical Thrushes’ and could all be matched with eggs of the Grey¬headed Thrush, though as a series they are more richly and hand¬somely coloured. The ground ranges from pale grey-green or sea-green to dull pale olive-green and from pale cream or buff to warm buff. The markings in some eggs are pale indefinite specks and freckles of reddish ; in others they are comparatively bold, though small, blotches of rather reddish or purplish-brown ; others are- intermediate between these two extremes. In all eggs the markings are numerous over the whole surface and little more so at the larger than the smaller end ; in some much of the ground is visible and in hardly any are the marks sufficiently dense to completely obscure it. Very rarely the blotches form rings or caps at the bigger end.
In shape the eggs are rather long ovals, seldom at all pointed at the smaller end. The texture is similar to that of the eggs of the true Thrushes and the surface has no gloss.
Fifty eggs average 30.0 x 21.3 mm. : maxima 33.0 x 21.2 and. 31.7 x 23.3 mm. : minima 26.5 x 20.2 and 30.0 x 19.2 mm.
603. Zoothera monticola
(603) Zoothera monticola Vigors.