(699) Chelidorhynx hypoxanthum (Blyth).
THE YELLOW-BELLIED FLYCATCHER.
Chelidorhynx hypoxanthum, Fauna B. I., Birds, 2nd ed. vol. ii, p. 275.
This tiny Flycatcher occurs in the West in Simla and Garhwal, and thence through Nepal and Sikkim to the extreme East and South of Assam. It also extends throughout the Burmese higher ranges to Tenasserim, but whether and, if so, where it breeds in these hills is not yet proved. It certainly also breeds in Eastern Tibet and Yunnan.
The differing elevations at which these birds breed are very puzzling. Thompson found it breeding at about 1,000 feet in the Kuman Bhaber, West of the River Sarda ; I found its nest at 3,500 to 5,000 feet in the Assam Hills ; B. B. Osmaston took othersat 7,000 and 7,500 feet near Darjiling ; A. E., Osmaston found them breeding in the Tons Valley at 11,000 and 11,500 feet ; and finally, Whymper took a nest at 12,000 feet at Dandar, in Garhwal.
It is a bird of deep forest, haunting ravines and the banks of streams, and I have never seen it in open country except when migrating to low levels in the Winter.
In North Cachar I had two nests brought to me in May and found one myself with young in June. Two nests were built on horizontal branches of small trees hanging over little streams in dense evergreen forest ; the other was built on the ridge of a great slab of rock jutting out from the bank of a stream in similar forest. The nests were all alike, tiny affairs with straight sides, the top and bottom being equal in size, or the latter slightly bigger. In diameter they measured externally about 2 inches by about to 2.3/4 inches in depth, with egg-cavities about 1.4 x 1.1 inch. The only material used was fine fluffy moss, with the tiny roots still attached ; this was well matted together, the roots more numerous inside than outside the nest, forming a very compact, strong little cup. In two nests the outer walls were plastered with cobwebs and white lichen ; in the third, which was the first taken, there was no lichen at all. The two nests on branches were about 5 and 6 feet respectively above the ground, whilst that on the rock may have been 7 feet above the stream.
In 1896 B. B. Osmaston found a nest in the Tons Valley, in Garhwal, between 11,000 and 12,000 feet. This he describes (Journ. Bomb. Nat. Hist. Soc. vol. xi, p. 70, 1897):—“On June 11th I noticed a Willow-Warbler enter its nest high up on a bough of Silver-fir. My orderly was told off to scale the tree and, while he was thus engaged, I noticed a pair of Yellow-bellied Fantails in the same tree which seemed much upset by the intrusion. I watched them carefully and, just as my man reached the ground, I saw one of the Fantails settle down comfortably on what looked like a little lump of moss on a small branch of the fir, not six feet from where the Willow-Wren’s nest had been.
“The nest is in shape rather cylindrical, 2.3/4" in external diameter and 1.1/4" across the inner diameter. The depth of the cavity is about 1" and that of the nest about 3". It consists of moss, firmly com¬pacted together and covered with grey lichen. It has a scanty lining of moss fruits with their stalks.”
The nest contained two hard-set eggs.
Later A. E. Osmaston took another nest in Garhwal and Whymper took many. The former describes his nest as exactly like that taken by his brother, but bigger, 3 inches in diameter and placed 15 feet above the ground on a horizontal branch of a Silver Fir.
Whymper says of one nest taken by him :—“Nest a very beautiful one, a truncated cone 2.1/4" high, made of moss and lined with hair and feathers, completely coated outside with lichen. The cavity is 1.1/4” deep and about the same across. This was placed on a silver fir. Other nests were exactly similar but were usually built on deodars, rhododendrons and birch-trees, between 11,000 and 12,000 feet. They all contained three eggs.”
My nests at the lower levels were taken in May, but all those at higher elevations, including those taken by B. B. Osmaston at 7,000 feet, near Darjiling, were taken in June.
Hodgson describes the nests of those seen by him in Nepal as exactly similar to those found by Osmaston. Thompson’s nest was also similar but he gives the breeding season as May and June.
The normal full clutch seems to be three, though two nests were taken by Osmaston in Darjiling with only two eggs each.
The eggs are very beautiful, like tiny pink pearls, with a deeper pink flush at the larger end. In reality they have a ground-colour varying from almost white to a delicate creamy pink, marked with a faint ring at the larger end of deeper pink, composed of the most minute stippling. In some eggs the rings are well defined, in others hardly visible.
In shape the eggs are broad, obtuse ovals, the texture rather coarse, but strong for such tiny eggs, while the surface is quite glossless.
Twenty-four eggs average 14.4 x 11.3 mm. : maxima 15.3 x 12.0 mm. ; minima 13.2 x 10.7 and 14.0 x 10.6mm.
699. Chelidorhynx hypoxanthum
(699) Chelidorhynx hypoxanthum (Blyth).