(1965) Arborophila atrogularis.
THE WHITE-CHEEKED HILL-PARTRIDGE.
Arboricola atrogularis Blyth, J, A. S. B., xviii, p. 819 (1849) (Assam). Arboricola atrigularis. Blanf. & Oates, iv, p. 127.
Vernacular names. Peura (Sylhet); Du-boi, Dubore (Assam); Sun-batai (Chittagong); Dao-bui or Dao-bui-yegashi (Cachari); Inrui-whip (Kacha-Naga); Toung-kha (Burm.); Wo gam or Gam-toung (Kachin).
Description.— Male and female. Forehead grey, changing to olive-brown on the crown and to rufous on the nape, each feather with a broad black spot; the grey forehead produced batik to form a supercilium, below which is a black line meeting the black lores and upper cheeks; back, rump and upper tail-coverts light olive-brown, the feathers tipped and barred with black; scapulars the same but more grey; innermost secondaries also similar but with bold terminal black bars and edged and mottled with rufous; wing-coverts olive-grey mottled with brown and sometimes, especially on the greater coverts, with rufous; quills brown, secondaries mottled with rufous and brown on the outer webs, which are greyish towards the tips ; tail mottled olive and brown; cheeks white, passing into rufous on the posterior ear-coverts, which have a few fine shaft-lines of black; chin, throat and fore-neck black; lower neck black and white; breast and flanks grey, passing into whitish on the centre of the abdomen; posterior flanks with white drops; under tail-coverts rufescent, edged with white and spotted with black.
The spotting on the flanks varies greatly. In one Assam bird there are also bold black-and-white spots on the breast but other birds from the same district are quite normal.
Colours of soft parts. Iris brown or red-brown; bill black; orbital and gular skin bright pink, becoming brilliant deep red in the breeding-season; legs dull orange to a bright orange-red, or red, during the Spring and Summer; in the female the bill is dark brown and the legs vary from dull wax-yellow to dark wax-yellow tinged with red.
Measurements. Total length about 275 mm.; wing, 135 to 147 mm., 126 to 130 mm.; tail about 60 to 65 mm.; tarsus about 42 to 44 mm.: culmen 18 to 20 mm.
Distribution. Assam South of the Brahmapootra; Dafla and Miri Hills, North of that river (Stevens); Cachar, Sylhet, Tippera and Arrakan into the Chin and Kachin Hills (Anderson); Myitkyna, Ruby Mine, at 2,500 feet (Whitehead)', Kamdoung (Bateman). Col tart and I both found it extremely common in Lakhimpur and Sadya in Assam, both North and South of the Brahmapootra and East of the Dibong.
Nidification. This Hill-Partridge is the low-level representative of the genus, 5,000 feet being about its maximum breeding-elevation, whilst it is common only at and below 3,000 feet, spreading right into the plains wherever the ground is broken up and there-is sufficient cover. Wherever found it breeds, commencing in April and laying up to the middle of June. The nest varies— sometimes it is just a hollow filled with leaves and grass, whilst at other times it is a most elaborate affair with the growing grass all round wound, twisted and bent into a complete canopy. In such a nest there is nearly always a thick pad of grass for the eggs to rest on and a neat tunnel of grass as an entrance, closed carefully whenever the bird leaves it. Pour eggs is the normal full clutch, sometimes three or five and, it is said, occasionally up to seven. One hundred eggs average 37.6 x 28.4 mm.: maxima 42.4 x 31.8 mm.; minima 32.4 x 26.2 mm. The hen bird is a very close sitter and once incubation commences will not leave until almost trodden on.
Habits. This species frequents both the plains at the foot of the hills and the hills themselves up to 5,000 feet but is most numerous below 2,000 feet. It spreads far into the plains where these are broken up and have small hills, intersected with ravines and patches of cultivation. Otherwise its habits are those of the genus, except that it prefers bamboo, scrub and grass cover to tree-forest.