(98) FIELD NOTES ON THE CORSICAN CITRIL . BY JOHN ARMITAGE. (Plates 3 and 4.) DURING the spring of 1937 my wife and I had many oppor­ tunities of observing the breeding habits of the Corsican Citril Finch ( citrineUa corsicana) in the centre and west of Corsica. Thanks to information kindly given by Lt.-Col. R. F. Meiklejohn and details from Col. W. A. Payn's records, we were in touch with Citrils during the greater part of our stay, and notes obtained tallied precisely with theirs, except in one locality where a few pairs had commenced to nest exceptionally early. The male of this form differs from that of the typical which occurs on the British list by its paler yellow underparts and by the warm brown instead of green of its mantle. The typical bird nests chiefly in large , sometimes at a considerable height; but the Corsican form does not breed in trees, although it prefers to be near them, and is closely associated with the white-flowered tree-heath (). It is evident that the Corsican Citril is a common resident of wide distribution in the mountainous parts of the island, and subject to local movement outside the breeding season. On May 6th, small parties were seen in open places among the low stony hills by the north-west coast, perching on rocks and rough ground, and flying about the maquis-covered slopes. They were readily approached and watched from close range, feeding on seeds of grasses and other low-growing plants, and nipping off tender shoots of plants still in flower. When disturbed, they flew up without travelling far, producing a whinnying and metallic flight-call, and it was these notes— reminiscent of Siskins, but distinctive—that made the prompt location of Citrils a simple matter at all times. On May 8th, and again on May 14th, Citrils were seen associating with Serins in two widely different districts, and when flushed, the former twittered and displayed dull greenish rumps, while the Serins contrasted by remaining silent and exhibiting in flight the characteristic yellowish streaks on their lower backs. Citrils in small parties and in pairs were noted high in the Tavignano Valley on May 15th, and three days later about 14 miles farther south, many were settled for breeding on a mountain slope a few hundred feet above an extensive forest of beech and . Lanky heath predominated on the lower part of the slope, but on higher and more exposed ground, the heath grew in isolated patches, dense and matted. Here VOL. xxxi.] CORSICAN CITRIL FINCH. 99 and there were young conifers, and in these and on top of the tufts of heath, cock Citrils were singing happily, their yellow unmarked breasts showing up brightly in the sunshine. The song is sweet and uttered in short phrases, punctuated occasionally with a canary-like " deek". A pair fussed about a short clump of heath a few feet from where we stood, and the hen carried building material into it without displaying the slightest objection to our presence. Next day, a closer search revealed our first nest with three fresh eggs from which the hen was flushed. It was a little over three feet high in a slender fork of heath, and sub­ sequently it proved to be typical both in position and nature of building materials. The nest was a small neat structure with a strong outer fabric of fine stems, grasses and roots mixed with moss, and the rather deep cup was smoothly lined with feathers, hair, and vegetable down. May 22nd found us in a picturesque western locality where for a week among the mountains, we studied Citrils daily in a variety of haunts ranging from 2,800 feet to about 3,500 feet, and sixteen tenanted nests were located. Every suitable patch of heath held one or two pairs of birds, and on a small slope dotted with isolated clumps close to the upper fringe of a chestnut forest, three pairs were breeding. Some nests were built in tall cover, from three to six feet high, and others were well concealed in goat-cropped heath, a few inches to two or three feet from the ground. Most nests held four eggs or young, and two, each held three young and one infertile egg. The only clutch of five eggs was four feet high in a fearsome tangle of bramble ; the nest was completely screened from view and was shown to us by the owners calling excitedly from the bush top, the hen working through to her nest soon afterwards. Incomplete nests, fresh eggs and others near to hatching were found on May 23rd, and we fell in with two pairs of greatly agitated Citrils. A brief search disclosed three scattered young, with stumpy tails and wings capable of sustaining them on short flight. Their recently vacated nest was seen and about twenty feet away, another nest held four fledglings ready to leave, one youngster sitting on top of its companions in the overcrowded nest. Both nests had their rims thickly fouled with excreta from the young. Seeing that most Corsican Citrils do not commence to breed until well on in May, this was a surprising discovery, proving that nest-making must have been in progress during the latter half of April. Anxious to watch and portray the big nestlings being fed, I rigged up a hide in the failing light.and enclosed the young and nest in my partner's hair-net to detain them until the morrow. 100 BRITISH BIRDS. [VOL. xxxi. All went well and both parents came to the young, between periods varying from three-quarters of an hour to nearly two nours. They were fed on small tablets of white regurgitated food. The adults then flew out of the district immediately, and by getting their " line " at midday, we saw they were collecting seeds by the roadside almost a mile below their nesting ground. During their absence, the young sat together in a heap quite amiably, looking round for a time and then dozing peacefully. At a nest with four young in pin-feather, the hen fed her offspring with a sticky white substance that squelched from the corners of her mouth, and at a nest with very small young, the visiting hen invariably ate her brood's excreta before leaving. Always, the incoming parents twittered in flight, and were answered with an expectant " tsip " from the fledged young, and by an occasional " deek". Further finds and periods of watching showed that nests with young are left unguarded for long periods, even when the nestlings are downclad, and it is likely that such nests might be overlooked unless every clump of heath on the mountain slope is peered into. Also, a pair of birds leisurely collecting food by the wayside might give one the impression that they had not begun to build when actually they were rearing a family. Bush-tapping is a dreary though successful method for flushing hens from their nests, and passing Citrils may be picked up through glasses and traced direct to their nests, but one should stay in a likely area for two or three hours to watch down adults feeding nestlings, unless all suitable clumps of heath are parted and examined carefully. By May 28th we knew of four nests of young in various stages; two other broods were strong on the wing, and there was evidence of one nest being built to accommodate a second brood. The down on a day-old nestling is dark brownish-grey, long and plentiful; distribution, inner and outer supra-orbital, occipital, humeral, femoral, spinal, ventral, and crural. The bill is purplish-grey, with dark grey tip to upper mandible. The mouth inside is dull red, tongue similar and unmarked ; external flanges ivory, with pink spot at extreme corners. A nestling about eight days old—in pin-feather—has plenty of long smoky-grey down still adhering. The inside of mouth and tongue are dull scarlet. Colour of external flanges and of corners as in day-old young. Bill horn colour; legs with purplish cast. A fledgling ready to leave the nest has creamy buff under­ pays, and is brown and striated above. Legs are pale brown. The bill is horn, with darker upper mandible, bill of parent seeming distinctly grey when noted together at feeding time. British Birds, Vol. XXXI., PL 3

Two typical haunts of the Corsican Citril Finch (Photographed by John Armitage) British Birds, Vol. XXXI., PI. 4

Hen Citril Finch with fledged young Cock Citril Finch on tree-heath (Photographed by John Armitage)