PHOTOGRAPHIC STUDIES OF SOME LESS FAMILIAR BIRDS XCVII. YELLOW-BREASTED BUNTING

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1 PHOTOGRAPHIC STUDIES OF SOME LESS FAMILIAR BIRDS XCVII. YELLOW-BREASTED BUNTING Photographs by ERIC HOSKING (Plates 25-32) Text by I. J. FERGUSON-LEES OF THE THIRTY species of true buntings (Emberiza) in the Palaearctic, only five have breeding distributions which straddle the whole width of Asia and extend into Europe, and one of these is the Yellow-breasted (E. aureola). It is true that in Europe, outside Russia, it is confined to Finland as a breeding species, but from there it extends right across Siberia to Manchuria, Korea, Japan and Kamchatka, chiefly between about latitude 5o N. and the Arctic Circle. Further, it appears to have extended its range in Finland during the present century from the ceded territory of Karelia to the shores of the Gulf of Bothnia and, though the Finnish population is still estimated at not more than 100 pairs (Merikallio, 1958), some colonies have been discovered only in the last ten years. Thus it may continue to spread westwards, though, as the species has a south-easterly migration and appears to be confined in winter to S.E. Asia, it is unlikely at the moment to occur with much greater frequency in western Europe: to date there are only eleven British records and a small scattering from Continental countries as far west as the south of France. The first Yellow-breasted Buntings to be found in the west of Finland were located in the Oulu area in 1920 and there were inland records in the 1930's and i94o's, but it was not until 1952 that the first of the larger colonies in the marshland on the eastern shores of Liminganlahti Bay was located: this held 15 pairs in 1952, 19 in 1957 and about the same in Other pairs and colonies have still more recently been located in the same general area south of Oulu and in one or two other districts on the Bothnian coast. With much help from Nils Fritzen and J. Siira, to whom we are particularly grateful for introducing us to the birds, and from C. J. Booth, three nests were found at the beginning of July 1958: two in the original colony on the shores of Liminganlahti Bay and the third about four miles away near Kempele. It is the last nest that appears in these photographs which, with the exception of the habitat ones, were all obtained on 9th July. The typical Finnish habitat is the vicinity of willow thickets or birch scrub in marshland or sometimes in adjacent grassland'; but elsewhere, according to The Handbook, dry scrub and steppe country are also favoured. The three nests we found in Finland in 1958 were in a variety of sites, but all were on the ground and not "in low bushes, on stumps... usually 2 or 3 ft. from ground" 161

2 162 BRITISH BIRDS [VOL. LII as described in The Handbook: ground-nesting- appears to be normal in Finland. One nest was among- a tangle of rank grass, reed and meadowsweet growing- several yards inside a willow thicket 6-9 feet hig-h (plate 29 lower). The other two were yards from the nearest bushes, one in rank vegetation if-2 feet high (plate 29 upper) and the other in quite short grass right out in the open. Thus the site seems to be as variable as it is with Reed Buntings (E. schoeniclus) which, incidentally, were common in the thickets and surrounding- marshland where the Yellowbreasted Bunting's were. A description of the nest itself appears under plate 31, but it might be added that one of the nests we found was little more than a scantily lined hollow. The Handbook gives the normal clutch-size as "4-5, rarely 6", but two of the three nests contained 6 eggs and 6 young respectively and the third was not revisited after the day on which its fifth egg was laid: we understood that 6 eggs appeared to be the usual clutch in Finland. Both sexes are said to incubate and the male was flushed from the nest with the incomplete clutch on one occasion. "Injury-feig-ning" was observed when a female was flushed from a nest in the twilight of the sub-arctic night. The male assists in brooding the young (plate 31) and in feeding- them. According to Dementiev and Gladkov (1954; see Harber, 1955), incubation takes 13 days and the young leave the nest when days old. Details of the breeding plumages are given in the captions to the plates and need not be repeated here, except in so far as it is worth drawing attention to the distinctive head-pattern and colouring of the female (see especially plates 26 and 28): the striped head is quite noticeable in flight and with the blackstreaked yellowish-brown back the general impression is not unlike that of an Aquatic Warbler (Acrocephalus paludicola), though, of course, the shape and size are very different. With the additional distinction of the unmarked breast, the whole appearance is paler and more contrasting than is the case with the female Yellowhammer (E. citrinella) or Cirl Bunting (E. cirlus). The double wing-bar which is often quoted can be very inconspicuous, particularly in worn plumage; the second wingbar on the male is similarly rather indistinct (plates 27 and 32 left). There is only one British record of a male in full plumage (antea, vol. xlv, p. 230; Scot. Nat., vol. 63, pp ) an d so it should be remembered that in the winter male much of the black on the face is lost, the chestnut upper-parts and breast-band are partly obscured by buff tips, and the wing-patch is buffish freckled with dusky marks. The song, though simple in pattern, is unusually melodious for a bunting: though often likened to the song of the Ortolan (E. hortulana), it is faster and much more liquid and musical, with a considerable carrying power of up to a quarter of a mile in good conditions. It is often uttered from exposed twigs in the willow thickets (plate 29 lower). More important to observers in this

3 VOL. LII] YELLOW-BREASTED BUNTING STUDIES 163 country, the normal call-note is a very distinctive "tick" that is astonishingly like that of a Robin (Erithacus rubecula). REFERENCES DEMENTIEV, G. P., and GLADKOV, N. A. (1954): The Birds of the Soviet Union. Moscow. Vol. 3, pp HARBBR, D. D. (1955): Special Review of The Birds of the Soviet Union. Brit. Birds, xlviii: 450. MERIKALLIO, E. (1958): Finnish Birds: Their Distribution and Numbers, Helsinki, p. 153.

4 PLATE 25 MALE YELLOW-BREASTED BUNTING (Emberiza aureola) AT NEST: KEMPELE, FINLAND, O.TH JULY 1958 The male in breeding plumage is unmistakable and the general pattern is well shown here: dark chestnut above and yellow below, with a narrow chestnut band across the breast, a black face and a conspicuous white patch on the wing. The amount of black on the face varies and does not stand out from the chestnut except at closer ranges, so that the chestnut division of the yellow under-parts and the white wing-patch are the most striking features.

5 PLATE 26 FEMALE YELLOW-BREASTED BUNTING (Emberiza aureola): FINLAND, JULY inrg The female is yellowish-brown above, broadly streaked with black on?he mantle and scapulars with a chestnut tinge to the rump; the under-parts are mainly unmarked yellow more or less tinged with buff, with purer buff on the sides and under-tail, and streaking only on the flanks. The general effect is *?7 Pak b ' rd Wlth a notlcea My freaky back, two pale and narrow wing! bars and a conspicuous pattern of light and dark stripes on the head (see plate 28 and pages ).

6 PLATE 27 MALE YELLOW-BREASTED BUNTING (Emberiza aureola): FINLAND, JULY 1958 This shows the inconspicuous second wing-bar formed by the bumsh-white tips to the greater coverts, but except in fresh plumage it is less distinct than many book illustrations suggest. Note also the broad chestnut-black streaks on the flanks. There is a white band across the outer tail-feathers (see plate 25), but this is usually seen only in flight when it adds to the bird's shape and wing-patch to give the male a superficial resemblance to a Chaffinch (Fringilla coelebs).

7 PLATE 28 FEMALE YELLOW-BREASTED BUNTING (Emberiza aureola): FINLAND, JULY 1958 The upper photograph shows the two wing-bars which are often too inconspicuous to be very useful as a field-character, and the lower the singularly stripy head. The yellowish-brown crown-stripe is bordered with blackish which in turn gives way to the broad yellowish-buff eye-stripes; a dark line through and behind the eye, and a dark line below the brown ear-coverts add to an effect which with the streaky back recalls an Aquatic Warbler (Acrocephalus paludicola).

8 1'l.ATR 2g YELLOW-BREASTED BUNTING (Emberiza aureola) HABITATS : FINLAND, JULY 1958 The surroundings of the photographed nest (upper) were open; the nest itself was in a tangle of grass and other rank vegetation such as horsetails, 1^-2 feet high, in which shoots of willow were growing, but it was some 30 yards from the bushes in the background. By contrast, the lower shows the site of another nest which was well inside and under a thicket of willow 6-9 feet high (see page 162); dead twigs such as those on the left were favourite song-perches.

9 PLATE 30 PAIR OF YELLOW-BREASTED BUNTINGS (Emberiza aureola): FINLAND, JULY 1958 Both sexes feed the young and here the female is about to remove a faecal sac: these may be swallowed or taken away. Food at this nest consisted of hover-flies, clegs, crane-flies, lacewings and various caterpillars. Note again the broad buff eye-stripe of the female. There were six young here and this appears to be a commoner clutch and brood-size than The Handbook suggests (see page 162). The nestlings have blood-red interiors to their mouths.

10 PLATE 31 Eric Hashing MALE YELLOW-BREASTED BUNTING (Emberiza aureola): FINLAND, JULY 1958 Incubation is mainly by the female, but both sexes take turns in brooding the young. Nests are made of dead grasses lined with finer grasses and sometimes a few hairs (no feathers). Contrary to the statement in The Handbook, most nests in Finland are on the ground, in more or less dense vegetation with or without bushes (see plate 29 and page 162). This is one of the smaller buntings and it has a fairly short tail, but it does not seem strikingly small in the field.

11 PLATE 32 Eric Ho skin g MALE AND FEMALE YELLOW-BREASTED BUNTINGS (Emberiza aureola) AT NEST: KEMPELE, FINLAND, QTH JULY 1958 In each case the parent bird has adopted the familiar air of expectancy with which Passerines wait, after feeding their young, for the passing of a faecal sac. Note how the yellow above the male's chestnut breastband extends conspicuously on to the sides of the neck; the second wing-bar and the extent of the dark streaking on the flanks are also well shown here. The beak is dark brown on the upper mandible, paler at the base and on the lower mandible.