PHOTOGRAPHIC STÜDIES OF SOME LESS FAMILIÄR BIRDS LXXXI. ORTOLAN BUNTING

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1 PHOTOGRAPHIC STÜDIES OF SOME LESS FAMILIÄR BIRDS LXXXI. ORTOLAN BUNTING Photographed by K. KOFFÄN (Plates 33-35) ALTHOUGH only a vagrant in Britain, the Ortolan Bunting (Emberisa hortulana) has a wide distribution in the Palaearctic region, breeding in most parts of Continental Europe from Spain in the south to the arctic circle in the north, and in south-west and central Asia as far east as western Mongolia. It is a summervisitor, wintering almost exclusively in Africa north of the Equator, only a few remaining in the south of Europe. It has no subspecies, but in the south its breeding-range overlaps those of two similar and closely-related species, E. buchanani in Persia and Turkestan, and' E. caesia. in Greece and Asia Minor. Notwithstanding its distant and restricted breeding-range, the latter species, known as Cretzschmar's Bunting, might just conceivably occur in Britain, for it was at one time recorded as a fairly regulär spring-visitor to Heligoland. continued

2 198 BRITISH BIRDS [VOL. L The Ortolan Bunting has a curious distribution in Europe, being common in the Mediterranean area (where it has gained an unenviable reputation for gastronomic excellence) and also in Sweden and Finland, but considerably less numerous in intervening areas. It is, for example, absent from north-west France, Denmark and the westernmost bulge of Norway, and decidedly local in north-east France, Switzerland, Belgium, Holland and north Germany. In the last twenty years, however, it has been extending its ränge in these countries and has increased considerably in numbers, probably due to climatic changes, but doubtless also in part to the recent prohibition of trapping in France and Belgium. J. Spaepen (1952, Gerfaut, vol. 42, pp ) has recently summarized its distribution in Europe, and gives also an interesting account of its migration, including an account of field-observations in Belgium and a list of ringing-recoveries. So far there has been only one recovery of a bird from Scandinavia, a nestling ringed in Finland and recovered in its first autumn in northern Italy. This, however, is of particular interest, as it suggests that the northernbreeding Ortolans follow a rather more easterly route in autumn than some other species which breed in the same area, and thus keep well away from the British Isles. Nevertheless, a few are recorded each year in Britain, either in May or in late August or September, and it is in fact one of the commonest of the rarer Continental "drift-migrants" on the east coast, sharing this distinction with the Bluethroat (Cyanosylvia svecica), a species of somewhat similar distribution. It is most numerous on Fair Isle, where as many as 15 were seen in May 1952 (antea, vol. xlvi, p. 424), but occurs fairly frequently along the whole of the east coast of England and Scotland and, more rarely, on the south coast. It is again fairly regulär on the islands in the Bristol Channel area, occurring annually on Lundy, and less frequently on Skokholm (where Mrs. Angela Davis's photograph reproduced on plate 36 upper was taken in 1956), but is otherwise rare in the west, and there are only three records for Ireland'. But for its elusive behaviour and undistinctive autumn plumage it would doubtless be recorded much more frequently. In spring the male Ortolan (plates 33 upper and 34) is a distinctive bird, with an unmistakeable greenish-grey head and breast, set off by warm rufous under-parts, ä yellow throat and moustachial stripe, a bright pink bill and a startling yellow eyering or "spectacle". In this plumage it could hardly be confused with any other European species except Cretzschmar's Bunting, which has a similar plumage-pattern, but a bright bluish-grey head and orange throat. Females are less brightly coloured and often lack some of these characteristics plates 33 lower and 35, for example, show a bird with little trace of the celebrated "spectacle" but are usually distinctive enough: it is the juveniles in autumn which present the greatest difficulties (see antea, vol. xlix, pp ). Although some autumn birds such as that

3 VOL. L] ORTOLAN BUNTING STUDIES 199 illustrated in plate 36 Upper still show a prominent eye-ring, in the majority of juveniles this is reduced or lacking and the colours are obscured by brown tips to the feathers, while the distinctive pink colour of the soft parts is often slow in developing. Such birds must be identified by more subtle characteristics, of which two are well shown in the photographs. Plates 33 and 35 illustrate the neat patterning of the mantle and wing-feathers which is a noticeable feature at all ages, while plates 35 and 36 upper show particularly well the flat forehead and the pale, deep-based bill, which in conjunction with the large dark eye give the bird a mysterious, staring expression which is very characteristic. Once the bird is known, however, it is much more readily identified by its call-note, a high "tlip" or "pwt" with a distinctive soft and liquid quality. Autumn migrants are usually difficult to observe, sometimes skulking in cover, and at other times wild and shy, perching high and flying far when only slightly disturbed. In summer the Ortolan Bunting occurs in a wide variety of habitats, ranging from Mediterranean scrub through all kinds of waste ground to alpine pastures and Clearings in northern forests. At least in northern Europe, however, it is characteristically a bird of cultivation, and is particularly associated with cornfields, frequently nesting in the growing com and feeding in the stooks and stubbles after the härvest. Its habitat requirements have recently been discussed by S. Durango (1948, Alauda, vol. 16, pp. 1-20), by H. Bruns (1951, Orn. Abhandl., No. 12) and by P. GeVoudet (1954, Nos Oiseanx, vol. 22, pp ). It appears that it needs not only a warm dry summer climate with open ground available for feeding, but also an adequate supply of high perches, and enough cover to hide the nest without being too thick to allow the birds to approach it on foot. This combination of requirements doubtless accounts in part for its broken distribution in Europe, and for its curious patchiness even in areas where it is common; another important factor is probably its association with agriculture, for it has probably colonized much of the northern part of its ränge in comparatively recent times,' after the clearance of natural forests and the drainage of marshes processes which are still continuing. Mr. Koffän's excellent photographs were taken in Hungary, and illustrate well the nesting habits of the species. The nest is nearly always on the ground (only two out of 102 nests described by Durango were not), and is usually well hidden under thick Vegetation. It is rarely built more than fifty yards from some prominent perch which is occupied by the male during incubation, and used by the female as a look-out post on her journeys to and from the nest. Mr. Koffän's nest contained four young, but clutches of five appear to be the most frequent, at any rate in southern and central Europe, while clutches of six are not rare. It is a late breeder, nesting from mid'-may onwards in central Europe, but mainly in early June in the north, and normally has only one

4 200 BRITISH BIRDS [VOL. L brood, although second clutches are not infrequently recorded in Germany. Geroudet (1951, Nos Oiseaux, vol. 21, pp. 1-6) describes a curious incident in which a female Ortolan apparently rernoved all her young from the nest immediately after they had been ringed, abandoned them and at once started to build a new nest. I. C. T. NISBET ADDENDUM As we were about to go to press, we received a letter from Mr. Koffän with whom we had lost touch in recent months. Commenting on Mr. Nisbet's Statement that in the last twenty years the Ortolan Bunting has been extending its ränge, he teils us that this agrees with his observations in Hungary, particularly in the hüls of Budaörs, near Budapest, where his photographs were taken. During the last years the Ortolan's ränge has been continually widening there, "though in some of their traditional places the density has not increased". Moreover, it is also noteworthy that recently this bird has frequently been found in vineyards, and particularly in the shrubby, rocky areas surrounding such places. On one occasion Mr. Koffän found a nest in a hawthorn (Crataegus oxyacanthoid.es) about 20 cm. (=8 inches) above the ground, but most nests are actually on the ground in quite a variety of sites. For example, he has found a number of nests in thick grass in Clearings in coniferous woods (the nest shown in these photographs comes into this category); others among dense shrubs on a hill-slope facing south; and on rocky slopes covered with Clematis vitalha, facing east. In 1956 he found a nest with three young on one of the highest tips of the hüls of Budaörs, about 1150 feet above sea level, on a steep rocky slope almost without Vegetation, facing north-west, the nest being well built into the slope under a piece of stone. Another nest in 1956 was in a similar place on the flat side of an old quarry, facing south-east, deeply in under what was perhaps equivalent to about 3 cwt. of rock. In Hungary the Ortolan generally lays 4-5 eggs, and Mr. Koffän has only once found a nest with 6 and once one with 3. The Ortolan generally arrives in the hüls of Budaörs in the second half of April. Thus Mr. Koffän saw the first ones in 1951, 1952 and 1953 on i8th and igth April; in 1949 ön 28th April; and in 1954 on ist May. They are seen in pairs a few days after their arrival. In favourable weather nesting usually Starts in the first half of May; and there are sometimes two broods. The pair shown in the photographs were very shy: they spent a long time sitting or Walking on the branches of surrounding trees before flying to the nest, giving short anxious cries which might well be mistakenfor the calls of breeding Rock Thrushes (Monticola saxatilis). They never flew directly to the nest, but like many other terrestrial birds walked to and from it. They fed their young entirely on insects. I.J.F.-L.

5 Pl.ATE 33 K. Kofjän MALE ORTOLAN BUNTING (Emberiza hortulana) AT NEST This shows the position of a typical nest, on the ground and hidden at the base of fairly thick Vegetation. Both sexes attend the young, but the female alone builds and incubates, while the male mounts guard on a prominent perch near-by (See page 197). K. Kofjän FEMALE ORTOLAN BUNTING (Emberiza hortulana) FEEDING YOUNG BuDAÖRS, HUNGARY, I5TII Ji:NE 1952 This gives an Illustration of the bold pattern of dark streaks and lightish markings on the upper-parts ; when seen from bebind, thcsc markings form an inverted horseshoe-shaped area and contrast with the di.stinctive warm buff rump (see page iy<)).

6 PLATE 34 K. Koffdn MALE ORTOLAN BUNTINO (Emherisa hortulana) FEEDING YOUN'C: BUDAÖRS, HUNCARY, 15m JUNE 1952 In sumtner plumage the moles have a distinctive grecnish-grey hcad and breast, yellow throat and moustachial stripe, and warm rufous under-parts, the female being paler, duller and less green ; both sexes have a bright pitik bill. This photograph also shows fairly well the siriking eye-ring or "spectacle". This pair never ftew directly to the nest, but like many ground-breeding species walked to and from it (sce page 200)

7 PLATE 35 K. Koffdn FEMALE ORTOLAN BUNTING (Emberha hortulana) AT NEST: BUDAORS, HUNGARY, 15TH JUNE 1952 Unlike many females in summer, this bird has little trace of a light eye-ring, but the photograph shows well the neat pattern formed by the light edgings to the wing-feathers, and the bird's flat forehead which, with the pale deep-based bill and the large dark eye, gives it a curious facial expression. These are useful characters at all seasons. The clutch normally consists of 4-5 eggs, sometimes 6, and there were four young here ; they were fed entirely on insects.

8 PLATE 36 Angela Davis JUVENILE ORTOLAN (Emberiza horlulana): SKOKIIOI.M, 12TH SEPTEMBER 1956 The juvenile lacks the green, yellow and pinkish colouring, so that call-note, back-pattern, bull: rump, pale bill, white outer webs (as well as inner) to outer tail, and sometimes the eye-ring, are the best characters (but see pages 199, 206 and vol, xlix, pp ).