The Rufous-breasted, Black-chinned or Nilgiri Laughingthrush, Trochalopteron cachinnans, is a species of Laughingthrush endemic to Peninsular India.
Recent treatments move this from the genus Garrulax to the older genus Trochalopteron and treat the former taxa T. jerdoni jerdoni (Banasore Laughingthrush) and T. cachinnans cachinnans as two races of a single species, which is given the new common name of Black-chinned Laughingthrush. The race jerdoni is restricted to the Brahmagiri areas of Coorg and Wayanad, while the nominate race cachinnans is found in the Nilgiri hills. The race jerdoni has a grey breast with faint streaks. The two races are found north of the Palghat gap.
Interestingly Jerdon had noted that his T. jerdoni had a close affinity with the Nilgiri race well before the 2005 work by P C Rasmuseen.
T. jerdoni has hitherto only been found by myself on the peak of Banasore, a hill on the south-western edge of the Tognaad, at a height of between 5000 and 6000 feet ; but it will probably occur in other equally elevated ridges in that mountainous district or in the conterminous region of Coorg, from which it is not separated by any depression. Banasore is at no very great distance (say 50 or 60 miles) from the western slopes of the Neilgherries; and it would not have been at all remarkable had the Neilgherry species extended all along the crest of the Tognaad to Banasore ; but the mass of the heights intervening are mostly at a lower level than this species loves. South of the Neilgherries and the Tognaad occurs a great gap in the hill- region, narrow towards the west, but opening out into the plains of the Carnatic eastward. The Pulney hills rise out of this plain ; and they are continued, though at unequal elevation, westward to the Annamally range, which is believed to be still higher, at all events to include certain much more elevated points than.the Pulneys. It will be interesting to find what species of Trochalopteron inhabits this range, whether T. fairhanki, which is perhaps most probable, T. jerdoni, or a distinct race. I trust that some of the rising race of ornithologists in the south of India will ere long determine this point, as well as the extension of T. jerdoni to Coorg.
"?T. C. Jerdon
This species forages at the forest edge on invertebrates, nectar, flowers and fruits, mostly within 3 m of the ground, and mostly in the early morning and late afternoon. Peruvian cherry Physalis peruviana, Rubus and Hill Guava Rhodomyrtus tomentosa are favourite fruits.
The Black-chinned Laughingthrush nests from February to the beginning of June.
Race jerdoni of the Brahmagiris and adjoining Wayanad
A nest of this species sent me by Mr. H. R. P. Carter, who took it at Coonoor on April 22nd (when it contained two fresh eggs), is externally a rather coarse clumsy structure, composed of roots, dead leaves, small twigs, and a little lichen, about 5 inches in diameter, and standing about 4.5 inches high. The egg-cavity is, however, very regularly shaped, and neatly lined with very fine grass-stems and a little line tow-like vegetable fibre. It is a deep cup, measuring 2.5 inches across and fully 3.75 inches in depth.
A nest taken by Miss Cockburn was a much more compact structure, placed between four or five twigs. It was composed of coarse grass, dead and skeleton leaves, a very little lichen, and a quantity of moss. The egg-cavity was lined with very fine grass. The nest was externally about 5.5 inches in diameter and nearly 6 inches in height, but the egg-cavity had a diameter of only about 2.5 inches and was only about 2.25 inches deep.
Mr. J. Darling, Jr., says :"?" This bird breeds from February to May. I have found the nests all over the Nilghiris, at elevations of from 4500 to 7500 feet above the sea. The nest is placed indiscriminately in any bush or tree that happens to take the bird's fancy, at heights of from 3 to 12 feet from the ground. "In shape it is circular, a deep cup, externally some 6 inches in diameter and 5 or 6 inches in height, and with a cavity 3 to 4 inches wide and often fully 4 inches in depth. The nest is composed of moss and small twigs, at times of grass mingled with some spiders' webs : sometimes there is a foundation of dead leaves. The cavity is lined with fur, cotton-wool, feathers, &c. ... The eggs are two or three in number."
Mr. Davison tells me that "this bird breeds commonly on the Nilghiris, just before the rains set in, in May and the earlier part of June, bat it occasionally breeds earlier (in April) or later (in the latter end of. June). The nest is cup-shaped, composed of dead leaves, moss, grass, &c., and lined with a few moss-roots or fine grass. It is placed in the fork of a branch about 6 or 8 feet from the ground. The eggs are a bluish green, mottled chiefly towards the larger end, and sometimes also streaked with purplish brown. The normal number of eggs is two; sometimes, however, three are laid."
"...The Laughing-Thrush, builds a pretty, though large, nest, and generally selects the forked branches of a thick bush, and commences its nest with a large quantity of moss, after which there is a lining of fine grass and roots, and the withered fibrous covering of the Peruvian Cherry (Physalis peruviana), the nest being finished with a few feathers, in general belonging to the bird. The inside of the nest is perfectly round, and rarely contains more than two eggs, belonging to the owner. The eggs are of a beautiful greenish-blue colour, with a few large and small brown blotches and streaks, mostly at the large end. I have found the nests of these birds in February, March, and April. Occasionally the Black-and-white Crested Cuckoo, which appears on these hills in the month of March, deposits its eggs (two in number) in the nest of this Thrush.
More or less pyriform varieties are common. In some eggs the markings are almost entirely wanting, there being only a very faint brownish-pink freckling at the large end; and in many eggs. even some that are profusely spotted all over, the markings consist only of darker or lighter brownish-pink shades. Occasionally a few, almost black, twisted lines are intermingled with the other markings, and in these cases the lines are frequently surrounded by a reddish-purple nimbus.
The eggs vary in length from 0.92 to 1.08, and in breadth from 0.74 to 0.8, but the average of twenty eggs measured was 1.0 by 0.76.
This noisy bird is to be met with in all the thick woods on the summit of the Neilgherries, and its loud laughing call is often heard when the bird itself remains unseen. I have met it in no other locality. It is sometimes seen in small flocks, but often wanders about alone, though at no great distance from some of its species, with whom it continually keeps up a noisy communication as signal of the direction it is going, or of the abundance of food obtained. They keep chiefly to the lower branches of trees and brushwood; on being observed, they hop and climb up the stem and thick branches of the nearest large tree, but they do not appear to ascend to the tops of trees. I occasionally, though rarely, observed them hopping and feeding on the ground. They fly heavily, and never to any distance. The cry of the laughing thrush is very peculiar, and, once heard, cannot be forgotten ; it has a sort of cracked Punch and Judy laugh, and is no sooner commenced by one than several others take up the chorus. The chief food is fruit of various kinds, especially the pleasant fruit of the Brazil cherry (Physalis tomentosa), now so abundant in most of the woods in the neighbourhood of Ootacamund. It also occasionally feeds on caterpillars and other soft-bodied insects. On one occasion, I found the nest on a bank overhanging the road, on the top of the Nediwuttum Ghaut of the Neilgherries. It was made of roots, grass, and moss, and contained four long oval pure white eggs.
"?T. C. Jerdon