(1520) Eurystomus orientalis orientalis Linn.
THE BROAD-BILLED ROLLER.
Eurystomus orientalis orientalis, Fauna B. I., Birds, 2nd ed. vol. iv. p. 228.
This handsome Roller has a very wide range. In India it is found in the Himalayas from Kuman to Eastern Assam, while it also occurs in Ceylon and South-West India from Travancore to the Wynaad. It extends over the whole of Burma and thence East, all through the Indo-Chinese countries and Yunnan, to Manchuria and Eastern China. South it extends through the Malay Peninsula to Java, Sumatra, Borneo, the Philippines, Celebes and numerous other islands.
It is found in the plains near the mountains, but is most common between 1,000 and 2,500 feet, sometimes wandering up as high as 4,000 fect.
Unlike other Rollers, this bird is one of forests, the damper as well as the dry deciduous ones, I have seen a fair number of nesting sites of this Roller, though in some cases all I have been able to do is watch, note, and then pass on, the trees being unclimbable without the expenditure of much time, often not available. Two examples give a good idea of their favourite breeding haunts. One of the first nests I found was in a hole in an enormous dead tree standing in a patch of rice cultivation on the summit of a hill and surrounded on all sides by forest. The rice-patch was an old one, and the tree, which had been ringed and left standing, had the trunk comparatively sound but many of the limbs rotten and broken away. Some 60 or 70 feet up the trunk I noticed one of the Rollers disappear into a hole and, as I was camping not far away, we determined to have a try at it. Bamboos and canes were growing near by in. plenty, so it was merely a question of time and trouble to construct a kind of ladder up to the nest. Eventually bamboos were tied, two by two, to the trunk with green canes until they reached up to the place where the birds were breeding, a large natural hollow with a rather small entrance. Inside this hollow and about 2 feet from the entrance three egga lay on a bed of touchwood and chips, no nest of any kind having been made for their reception. Another pair of birds were found breeding in a gigantic Bombax in very high forest, standing beside a jungle-path. In the forest close to the tree nothing could be seen of the nest, as it was in a hole in the trunk above the surrounding trees, but we had spotted the birds and their nesting-hole while we were on an adjacent peak. The tree was one of the largest, and certainly the nest-hole was 100 feet from the ground and quite possibly a great deal higher. The nest took us two days to get at, being placed in a hole in a diseased swelling on one of the main great branches, only approachable by means of pegs driven into the trunk and then the branch itself. The pegs were steadied and strengthened by bamboos fastened to their free ends, the whole forming a primitive but very tough ladder, The diseased swelling was about 2 feet or more in diameter, and the whole of the interior had rotted away, leaving a round shell about 4 inches thick, with a small entrance on the underside barely 4 inches across by which the birds obtained access. No nest or lining was in the hole, the three hard-set eggs lying on the bare, very hard wood.
Occasionally holes are selected in rather smaller trees, lower down, yet very seldom under 30 feet. Other accounts of the nidification all agree with mine. Thompson says that in Kuman they are strictly confined to heavy forest and breed in holes in great trees never under 50 feet from the ground. F. W. Bourdillon obtained one clutch of eggs in a tree 40 feet up on the 17th of April and, later, a similar clutch on the 18th of April in a hole even higher up than this. In Burma Hopwood took a clutch of four eggs “very high up in a Tetrameles nudiflora tree” and Macdonald one “high up in a Pinkado tree in forest.”
The brothers Bourdillon give the breeding season in Travancore as September to May, but T. F. Bourdillon notes in the data on a clutch of eggs given to me that the season is March to May, months which correspond to the season in Assam and Burma,
A very curious fact noted by La Touche about this bird’s breeding in China should not be overlooked. He says that he found this Roller breeding freely about Foochow, where they invariably de¬posited their eggs in Magpies’ nests, a habit which is also recorded by David and Oustalet.
The full clutch of eggs is three or four, generally the latter.
Twenty-five egga average 30.3 x 28.2 mm. : maxima 36.9 x 26.1 and 35.0 x 29.3 mm. ; minima 31.7 x 25.6 and 32.5 x 25.3 mm.
Both birds incubate.
The same nest-hole is resorted to year after year, and one such, situated about 100 feet, up in an enormous Simul-tree, was occupied for about six years in succession.
1520. Eurystomus orientalis orientalis
(1520) Eurystomus orientalis orientalis Linn.