This is the third and last of this series of papers based on observations in

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1 Identification of Olive-backed Pipit, Blyth's Pipit and Pallas's Reed Bunting Alan R. Kitson Three species which occasionally reach western Europe. Knowledge of their field characters may help us to increase the number of vagrancy records This is the third and last of this series of papers based on observations in Mongolia in The general introduction to the series appeared with the first paper (Brit. Birds 71: ). Olive-backed Pipit Anthus hodgsoni From mid May onwards, this species becomes common in Mongolia, inhabiting forests and the interface of forest and mountain steppe. The race concerned is yunnannesis (Vaurie 1959), to which Dennis (1967) continued [Brit. Birds 72: , March 1979]

2 Olive-backed and BlytKs Pipits and Pallas's Reed Bunting 95 Fig. i. Olive-backed Pipit Anthus hodgsoni, Mongolia, June 1977 (Alan R. Kitson) tentatively assigned the two autumn vagrants on Fair Isle in 1964 and Olive-backed is easy to identify and, although this has been understood by those who have recently encountered it as an autumn vagrant in Britain, the diagnostic characters have not been properly analysed in any of the current field guides. In size, Olive-backed is similar to Tree Pipit A. trivialis. It is definitely not smaller, as stated by Peterson et al. (1974). In stance and gait, Olivebacked again recalls Tree, but, even more than that species, it habitually wags or, better, pumps its tail. The movement is so pronounced that it recalls that of a wagtail Motacilla, Those in Mongolia, both migrants and breeders, were notably timid. When disturbed, they would fly up, calling loudly and scatter into the tree canopy, perching on boughs and even hiding in dense foliage. Such behaviour has been shown by at least two of the recent Olive-backed Pipits in Britain (D. I. M. Wallace in litt.). As most texts point out (but few illustrations do justice to), Olivebacked is a beautiful bird, with obvious contrast between its dark olivegreen and relatively unstreaked upperparts (with feather marks much reduced even compared with Tree) and its clean, mainly white underparts. The latter are suffused yellow-buff and heavily spotted black in front and streaked black along the lower flanks. It is, however, the head pattern that is most distinctive. Crown basically olive, with heavy black flecking, and black line over supercilium. Supercilium obvious, buff-orange before and startlingly white behind eye: contrasting with dark eye-stripe which forms upper border to olive-brown cheeks and divides end of supercilium from obvious, white, drop-shaped mark on rear upper ear-coverts; last mark contrasts with noticeable black spot immediately below on rear ear-coverts which runs down around lower edge of cheeks. Combination of black-outlined white supercilium, white drop-like mark (appearing as broken end of supercilium) and black ear-spot unique among Palearctic pipits (see fig. 1).

3 96 Olive-backed and BlytKs Pipits and Pallas's Reed Bunting 35. Olive-backed Pipit Anihus hodgsoni, Mongolia, June 1977 (Alan R. Kitson) Some photographs of vagrants recorded in Britain have not shown the 'supercilium drop' (see, for example, plate 20 in Dennis 1967), but I suspect that it was obscured by the positioning of the birds in the hand; it is well shown in Broad (1976), in R. A. Hume's sketch of the October 1976 individual in the Isles of Scilly reproduced in Conder (1979) and in my photograph of one in the field in Mongolia (plate 35). The flight call of Olive-backed always reminded me of Tree and often also of Richard's Pipit A. novaeseelandiae. It was a hoarse 'tzee' or 'tzeep', much more striking than the thin, inflected call of Red-throated Pipit A. cervinus. It can sound surprisingly loud in close cover, even suggesting Redwing to some ears (D. I. M. Wallace in lift.). BIyth's Pipit Anthus godlewskii From mid May onwards, this pipit became common around Ulan Bator and was common in the Hangai in June, inhabiting dry, grassy hillsides. I found Richard's Pipit A. novaeseelandiae of the eastern race dauricus (Vaurie 1959) in the last few days of May at Ulan Bator and in June farther down the Toal Valley, confined to the rank vegetation of marshes and wet flashes below the habitat of BIyth's, from which it is clearly ecologically separated. Drawing upon this fortunate chance to compare them, I am able to comment on their differentiation in Mongolia. BIyth's is the same size as or slightly smaller than Richard's, usually assuming a less upright posture, appearing shorter-legged, but not showing in the field the slightly finer and less thrush-like bill obvious in skins. Occasionally, my patient use of a telescope made visible the short hindtoe claws of BIyth's and, more obviously, the ridiculously long hindtoe claws of Richard's. In plumage, BIyth's appeared almost identical to Richard's (of the race dauricus) and my notes on plumage could apply to both, apart from the colour (and prominence) of the tips to the median wing-coverts. In BIyth's, these were usually white or whitish, forming, with the black bases to the same feathers, a row of dark spots and a white wing-bar (see fig. 2). In

4 Olive-backed and Blyth's Pipits and Pallas's Reed Bunting 97 Fig. 2. Blyth's Pipit Anthus godlewskii, Mongolia, June 1977 (Alan R. Kitson) Richard's, the tips to the median wing-coverts were invariably buff, and the wing-bar was correspondingly less marked. Later, examination of skins showed that, whereas the tips to the median coverts were white on 63% of Blyth's, they were similarly coloured on only 7% of Richard's (of the races dauricus and richardi). Unfortunately, there is evidence that the Richard's which show white tips are immature. Two individuals so marked have been taken in Europe and thus the tentative separation suggested here probably applies only to adults. Thus far I have been comparing the two species as they appear in Mongolia. Drawing on my experience of 12 Richard's of the race richardi in autumn in Britain, I believe that Blyth's may be more easily separated from that form. It will appear as a confusing intermediate between Richard's and juvenile or immature Tawny Pipit A. campestris. It should look as large as the former, but be paler and tawnier in appearance, approaching the latter. Close study will, however, show richer plumage tones, including orange on the underparts (particularly on the undertailcoverts). Since a certain Blyth's in Finland in September 1975 showed clear orange-buff flanks (P. J. Grant in prep.), I sense that the elucidation of large pipit plumage characters is not far off. Initially, in Mongolia, I found the calls of Blyth's and Richard's similar, but, after much practice, I learned to separate them. The only call that I heard from Richard's was a rasping 'shreep', which had a dry tone recalling House Sparrow Passer domesticus and was precisely the same to my ears as the note of autumn vagrants in Britain. From Blyth's, I heard a dry, anxious 'dzeerp' (which I suspect is uttered only by breeders) and a harsh, terminally inflected 'psheeoo', somewhat recalling Yellow Wagtail Motacilla flava and far too coarse to cause confusion with Tawny.

5 9 8 Olive-backed and Blyth's Pipits and Pallas's Reed Bunting This second call was often prefaced by a soft, single or double 'chup', which did recall Tawny and is, I think, never given by Richard's. Considering the Finnish record noted above and the 19th century specimen from Sussex (Williamson 1977), the recurrence of Blyth's in Europe is probable, and most likely in autumn. Indeed, large pipits intermediate between Richard's and Tawny have sorely tried British observers in several recent autumns. Pallas's Reed Bunting Emberiza pallasi Almost the first spring migrant to reach Ulan Bator on 30th March was a small, buff-coloured bunting with a conspicuous pale rump, a pair of pale back-stripes, distinctly angled moustaches and a call that reminded me of Yellow-browed Warbler Phylloscopus inornatus. Its size and rust-brown cheeks suggested Little Bunting E. pusilla, but the call and pale rump puzzled me. On 10th April, I came upon a party of similar birds which included males and I realised that I was involved with Pallas's Reed Bunting. Throughout my stay in Mongolia, the species never became common, but I saw about 60 in all, finding migrants both in tussock grass and in the bases of clumps of willow Salix in the valley of the Toal River and among larch Larix and birch Betula at 2,000-3,000 m in the mountains. It also occurred in reeds Pkragmites at Orok Nor and was breeding in tussock grass within sight of water. Pallas's Reed is a small bunting, particularly so in comparison with Pine Bunting E. leucocephala. I judged it to be the same size as Little, although I was not able to compare the two species directly. Pallas's Reed showed the same tail movements as Reed Bunting E. schoeniclus: it frequently flicked its tail upwards, at the same time fanning it slightly and revealing the white outer feathers. The 60 that I came across exhibited much individual variation in plumage, and the males in particular showed three types which I interpreted as 'transitional (from winter)', 'spring' and 'full breeding'. In detail, the changing plumage of the males showed the following characters between mid April and July: 'TRANSITIONAL (FROM WINTER)' Highly of breeding plumage (fig. 3 c), typified by variable (fig. 3 a, b), but in mid April black head and usually long bib most still showed essentially winter separated by white moustache, neat white plumage, typified by general buff tone, nape-collar, suffused yellow or yellowwith this the ground colour of the back, orange on nape, pale back with prominent and with both nape-collar and rump pale stripes of black and grey-white (recalling fawn; head-pattern still fragmented, with zebra), unstreaked grey-white rump, pure dark brown cap separated by pale buff white underparts and obvious white tips supercilium (of variable length) from dark to black median and greater coverts; in brown or blackish cheeks, and black bib this plumage, they had black bills and usually patchy and incomplete; wing-bars brownish legs. buff, breast and flanks occasionally buff. Some had yellowish nape-collars and darker heads. 'FULL BREEDING' Four singing birds in July all had pure white nape-collars, 'SPRING' By 10th April, most males in lacking all trace of yellow; upperparts less transitional plumage (see above), but a contrasting than in April, but with rump few much brighter, showing main features still remarkably pale.

6 Olive-backed and Bljth's Pipits and Pallas's Reed Bunting 99 Fig. 3. Pallas's Reed Buntings Emberiza pallasi observed in Mongolia in (a) male 10th April; (b) male 28th April; (c) male 10th April; (d, e) females 30th March (Alan R. Kitson) Thus, while the male Pallas's Reed Bunting strongly suggests a small Reed Bunting and exhibits a basically similar plumage pattern, it does possess diagnostic characters. In spring, the white nape-collar is washed with yellow-orange and, in spring and summer, the black and pearl-grey (not black and brown) markings of the back and the conspicuously whitish rump are very obvious. The female Pallas's Reeds (fig. 3 d, e) showed much less variation in their plumage and appeared as essentially buffy occasionally brown buntings with pale rumps and heavily marked moustaches. In detail, their plumage may be summarised as follows: Forehead and crown brown (often with warm chestnut tone and darker flecks); supercilium pale buff-white, but no dark eye-stripe; cheek patch uniform brown, often with rust or mahogany tone and with or without black spot or comma-shaped mark in lower rear corner. Nape-collar fairly pale, grey-buff. Back buff or brown, overlaid with black streaks and showing pair of even paler buff stripes (on each side of back). Rump invariably pale, grey-buff or buff. Median coverts black, edged chestnut; greater coverts and tertials black, edged buff. Malar area between cheeks and moustaches white or buffwhite ; moustaches black, noticeably widening towards sides of breast and then, on some, turning downwards almost to join in centre of breast. Underparts basically white, not infrequently with buff wash on sides of breast and flanks and variable sparse brown flecks on same areas. Bill horn-brown, with flesh base to lower mandible. Thus, the female Pallas's Reed differs notably from Reed in its pale rump, heavy moustaches (not breaking out into similarly coloured streaks

7 ioo Olive-backed and Biyth's Pipits and Pallas's Reed Bunting on the underparts) and generally paler, buffier plumage. The pale back stripes and nape-collar also catch the eye. Both sexes share similarly coloured tails, with white outer, black inner and dark brown central feathers, and chestnut lesser wing-coverts, the latter apparently identical to those of Reed. I heard two calls from Pallas's Reed, both distinct from the calls of Reed and Little. The commoner utterance was a trisyllabic 'peeseeoo' reminiscent of Yellow-browed Warbler, the other was a 'ch-reep' recalling both House Sparrow and Tawny Pipit. Acknowledgements To the acknowledgements made in the first paper in this series (Brit. Birds 71: ), I wish to add my thanks to Tony Gaston, Steve Madge, Richard Porter and Michael Rowntree for additional notes on Green Warbler, and to Tim Inskipp for notes on certain species which he supplied when I was in Mongolia. Summary Field characters of Olive-backed Pipit Anthus hodgsoni, Biyth's Pipit A. godlewskii and Pallas's Reed Bunting Emberiza pallasi are described, based on observations made in Mongolia in spring and summer Biyth's Pipit is compared with Richard's Pipit A. novaeseelandiae. References BROAD, R. A Fair Isle Bird Observatory Report (plate opposite p. 34). CONDER, P Britain's first Olive-backed Pipit. Brit. Birds 72: 2-4. DENNIS, R. H Olive-backed Pipits on Fair Isle: a species new to Britain and Ireland. Brit. Birds do: PETERSON, R., MOUNTFORT, G., & HOLLOM, P. A. D A Field Guide to the Birds of Britain and Europe. London. VAURIE, C The Birds of the Palearctic Fauna, Passeriformes. London. WILLIAMSON, K Biyth's Pipit Anthus godlewskii in the western Palaearctic. Bull. BOC. 97: Alan R. Kitson, 45 Channel View Road, Woodingdean, Brighton, Sussex BN2 6DR