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Photo © Roy Harvey

Possible Horned Lark on the Isles of Scilly in October 2001

By Brian J Small

with photos by Andy Farr and Bryan Thomas from the Scilly 2001 Gallery

One of the more interesting birds in Britain during 2001 was a possible ‘Shore’ Lark Eremophila alpestris ssp. seen on St Agnes and Tresco, Isles of Scilly from 2nd October. Found by Darryl Spittle, this bird generated much discussion at the time, and I published an article in Birding World (February 2002) explaining why, after museum work, I thought it was of the North American race alpestris, colloquially known as 'Horned Lark' in the UK. Reactions to my article were few, but Darryl himself finally contacted me to say that,

"I too visited Tring with another birder who had seen the bird and whose opinion I value. However, unlike yourself, we came to the conclusion that, whilst the bird may well have been alpestris, it was impossible to be sure given the within-subspecies-variation displayed in the skin collection."


Possible Horned Lark, Isles of Scilly 2001 © Andy Farr (mail AT farr25.freeserve.co.uk)


Despite these comments from Darryl (and I am most grateful that he found the time to respond to the article and I will bring in his arguments later), I have revisited Tring, and still feel that my conclusions regarding the various criteria I put forward are sound. The purpose of this edited article is to prompt some discussion from birders in North America as to whether they feel that the Scilly bird is indeed an alpestris, whether the features discussed fit their image of that form, and hopefully draw together a library of images of the various forms in North America or elsewhere - to this end I include a list of the various subspecies recognised by Pyle and other authorities.

Horned Lark was formerly included on the BOU Checklist on the basis of a specimen obtained by Meinertzhagen from South Uist (discussed later), but was subsequently removed. However, the likelihood of Nearctic forms of Horned Lark turning up in Britain was raised by Garner (1999), regarding a Shore Lark observed in County Down, Northern Ireland in 1998. Pétursson and Ólafsson (1999) also describe a similar bird found dead in Iceland in November 1981. The Scilly bird shared many features with both of these birds and they almost certainly belong to the same race. As such this record would be the first record for Britain, hence my interest in it.

At the time of publication I felt sure it was one of the North American races. Reference to photographs of likely races and comparison with specimens housed in the British Museum, Natural History (BMNH) at Tring, leaves little doubt in my mind that the Scilly bird belonged to the nominate form alpestris, which breeds in the arctic regions of eastern North America. Even if the Scilly bird ends up being unproven, the process involved and the information gained will stand us in good stead should another turn up.

The Scilly Horned Lark

Darryl Spittle has written "I found the bird in question and overall the bird did appear different, being generally richly toned (particularly on the marginal/lesser, greater and uppertail coverts and flanks) and clean below, quite different from the classic grey/cold toned flava trundling about east coast saltmarshes. I also thought it appeared quite large (but relative size is, of course, notoriously difficult to judge in the field) and the extent of the grey on the rear of the ear-coverts also looks different from the bulk standard flava."

My first impressions were the same and it was important to see the bird from a variety of angles and in a range of lighting conditions in order to appreciate plumage tones and colour shifts. In strong sunlight, it seemed paler and pinker, notably on the mantle, with darker centres to the tertials; in shade or flat light, strong rufescent tones and heavy streaking were more prevalent. Its general colour and tone differed markedly from the perceptions of typical sandy grey east coast Shore Larks. Rich pinkish rufous or vinaceous tones stood out especially on the lesser and median coverts, with the tertials also seeming to have rich rufous-brown outer webs. The rich, dark upperparts and rufous breast sides and flanks contrasted markedly with white underparts.


Possible Horned Lark, Isles of Scilly 2001 © Bryan Thomas


The head showed the typical Horned/Shore Lark pattern, though the pale shadow to the rear of the ‘moustache’ was distinctly narrow, the grey ear covert patch large. The fore-crown was black - the black reaching back to almost level with the eye, but it was obscured by pale brownish tips; from the rear, the rear crown was strongly streaked darker. The yellow on the forehead, chin and throat was a bright primrose-yellow. At one stage it was attacked by a male Stonechat, which resulted in the ruffling of some of the lark’s crown feathers.

The upperparts were fairly rich warm brown (paler in strong light) with prominent black streaking on the mantle and scapulars - the apparent strength of the black streaks varied according to light, generally the black was slightly wider than the brown; a paler, sandy-brown area on the lower back contrasted with a rich pinkish, pinky rufous-brown rump and uppertail coverts. The rump was unmarked, whilst the upper tail-coverts had narrow black shaft streaks. The central tail feathers had broad black centres with quite narrow inner and outer edges; the outer rectrices appeared jet black and the pointed tips to tail feathers produced a small notch in the tail. The outermost rectrix also had narrow white outer edges.

The colour and pattern of the upper wing-coverts were distinctive. The lesser coverts were pinkish rufous and unmarked save for a few whitish tips and the median coverts were largely unmarked pinky rufous, but with small black spots in the upper corner of the inner web and prominent white tips. The greater coverts appeared wholly rufous brown with paler edges and small white tips. The colour and pattern of the tertials varied a lot according to angle and light: at times appearing to have a black inner web, rich rufous-brown outer web and pale cream edge; on other occasions it seemed to be wholly black, with limited rufous on the outer web. Importantly, at all times the blackness was distinct. The primary coverts were almost wholly pinkish brown, with a thin black shaft streak. The four primaries visible beyond the longest tertial were jet-black with narrow white tips, most marked on the tip of the primary showing just beyond the longest tertial.

On the area just below the black breast patch, there were strong darker streaks made up of dark triangular or arrowhead shaped streaks. These merged with rich rufous-brown breast-side patches and flanks, which were also streaked. The belly and vent were clean white; the thighs were warm brown and appeared quite shaggy at times.

The only call I heard the Scilly bird make was like a strong Meadow Pipit or an almost Richard Pipit-like "stree"; although I have heard Shore Larks call similarly, this seemed louder and differed from my recollections of flava in being more robust. I did not hear it make the characteristic call of flava.

Separation of Horned and Shore Larks

Following examination of specimens at BMNH, Tring, I suggest the following criteria, based on structure and plumage, might be of use in the separation of alpestris from flava.


nigrifrons Shore Lark © Peter Kennerley


Structure

Few structural differences exist between alpestris and flava, so perceived features such as primary projection or relative tail length are of little use in their separation; similarly, most measurements show an almost complete overlap. However, bill shape is consistently different and is as, or more, distinct as the bill shape of Eurasian Skylark Alauda arvensis and Oriental Skylark A gulgula (or even Richard’s Pipit Anthus richardi and Blyth’s Pipit A godlewskii). The tail shape may be a further clue.

Bill length and shape. A distinct difference between flava and alpestris is the shape and length of the bill. Measured from the tip to the nasal hairs that cover the nostril, the bill of alpestris is on average 2.0mm longer than that of flava. Although small, this measured difference gives a characteristic shape to the bill in the field, when it appears longer and more spiky, with a straighter edge to the lower mandible (hoyti has a similarly long and pointed bill). On flava, the bill tends to be shorter and stubbier, with a slightly convex edge to the lower mandible.

DS comments: "Bill structure - I believe the differences in bill structure may simply the result of alpestris being slightly larger on average, a large flava would have a relatively spikier bill with a straighter edge to the lower mandible."

Checking this feature I still feel tha structurally, the Scilly Horned Lark had a bill typical of alpestris, with a spiky tip and straight edge to the lower mandible, within the limits for alpestris and outside those for flava.

Outer tail feathers. The only other aspect that might help and be visible in the field is the shape of the outer tail feathers, which, irrespective of age, on alpestris seem consistently to be more pointed, and on flava tend to be more rounded at the tip. As a consequence, on alpestris and other Nearctic races the tail seems slightly notched, whilst on flava and other Palearctic races the tail may look more square-ended.

DS comments, "Outer tail - I can't really comment on this feature I simply did not see the small differences you describe on the skins (I accept I may have missed this) and I didn't note the outer tail feathers on the Scilly bird as particularly pointed (but then I didn't note them as particularly rounded either). I would suggest, however, that due to feather wear (particularly on a ground-feeding species) this feature may be of marginal value even in the hand."


flava Shore Lark © P Leasley


Plumage

Pyle et al. (1987) state that ‘no reliable plumage criteria are known for ageing (Horned Larks) after the first post-breeding molt’. Adult post-breeding moult in flava is complete by early October (Cramp et al, 1988), though it may be earlier in the Asian forms. Post-juvenile moult is usually complete by mid-October (Cramp et al, 1988), again possibly earlier in Asian forms. Due to the range of variability amongst adults, first-winter birds are indistinguishable from autumn adults (especially females) in the field; the following points are applicable to the separation of alpestris from flava in fresh plumage in autumn and winter.

Roselaar, writing in Cramp et al. (1988) states for Palearctic subspecies that first-winter birds are ‘similar to adults’ and ‘often indistinguishable’, though the inner fringes of the inner primaries on first-winters are rufous and not as greyish white as adults. Despite the difficulties in separating age and sexual differences in the field in autumn, Roselaar also indicates that adult males have the strongest face pattern and first-winter females the weakest, with the black almost completely obscured by pale fringing; first-winter males are very much like adult females. So it may well be, and specimens tend to support this, that the strength of the facial pattern of the Scilly bird was indicative of a male.

Head/upper breast pattern. The basic pattern and colour is very similar to flava; the black on the forecrown and above the supercilia is very similar, though evidence might suggest that the black on the fore-crown is more extensive on alpestris. The crown streaking, most obvious on the rear crown/nape area is broader and darker (black) on alpestris compared to the thinner and browner streaking on flava. The black loral area and moustache on the fore ear coverts is similar in extent and obscured by pale feather tips, but the pale area shadowing the black moustache is on average narrower on alpestris (thinner than the moustache) than on flava (equal to or broader than the moustache), leaving a larger olive-grey rear area on the ear coverts on alpestris. The face is perhaps more strongly washed yellow on alpestris, though variability makes this almost useless; the colour differs slightly in being a primrose-yellow in alpestris and more lemon- or citrine-yellow in flava. Alpestris has a subtly pinker crown and hindneck, and this is sandier and greyer in flava.

DS comments, "Head and upper breast pattern - the black on the fore-crown shown by the Scilly lark was no more extensive than that shown by many flava; in a similar manner the extent of crown/nape streaking was not beyond the variation shown in flava, in some photos, however, the streaks possibly appeared darker than the average flava; the greyish rear edge to the ear-coverts did look more extensive than the majority of flava; I don't think the colour or saturation of the yellow on the face is particularly useful in separation of individuals of these subspecies."

Upperparts. The mantle and scapulars are similarly coloured, with a tendency for alpestris to be slightly richer, but the most significant difference is that alpestris has broader dark (blackish) centres to the feathers compared with thinner and browner centres on flava; hoyti seems intermediate between the two, in being slightly paler and with less broad streaking. In the field, this gives alpestris a richer, darker and more heavily streaked appearance to the mantle. A subtle, but possibly significant, difference is that alpestris has a paler, less richly coloured lower back, which contrasts with the richer upperparts and even richer pink-rufous rump and upper-tail coverts; flava is more uniform in colour and with a more chestnut rump.

DS comments, "Upperparts - although on average alpestris shows slightly more saturated (darker/richer) upperparts, there was so much overlap in the specimens it was easy to locate birds which, on this feature alone, appeared to be in the wrong tray. I don't believe the bird was distinctly heavier streaked than some flava."

Closed wing. The pink-rufous median coverts of alpestris and hoyti appear more uniform with the lesser and marginal coverts. They show a neat white edge and a black spot on the inner web away from the shaft (a few show a small brown mark on the outer web, but this is obscured by the overlying feather). On flava, the colour of the feather is a darker orange-brown, with more prominent dark brown inner and outer webs and on average a marginally broader white tip. The greater coverts differ subtly also: on alpestris the inner area (inner web) is darker, black almost, with a pinkish rufous area on the outer web and neat, quite small white tips; on flava, the centres are paler, with a more ochrous brown edge and, on average, a wider white tip to outer web. The tertials are similarly patterned with a blacker inner web and more rufous outer web on alpestris (at varying angles the feather centre can look all black); on flava they are slightly paler, brown-black inner webs and less rich outer. The primary coverts are edged more richly on alpestris. The effect of the warmer rufous coverts on alpestris is to give a richer look to the wing.

DS comments, "Closed wing - I had anticipated that the median coverts of the Scilly bird would prove a bit of a clincher, however, on inspection of the skins a number of flava showed pinkish medians that did not contrast strongly with the marginal/lessers; I did not see (and have not seen photos of) the inner
webs of the greater coverts well enough to determine the subtle differences you described; yep, the outer webs appeared warmer than the average flava
but I couldn't see any real difference in the white-tipping; and finally I think any differences in tertial pattern/colour could only be seen with series of skins laid out on the bench, I don't think the Scilly bird was particularly notable in this respect."

Underparts. The breast-sides and flanks are washed a richer and darker rufous in alpestris, with broader dark streaks; paler and less rich in flava (though a few show richer flanks similar to the nominate). The most striking aspect of the underparts is the contrast between the rich flanks and breast side patches and the clean white belly; this compares with the paler and sandy pink flanks and dingy white underparts of flava. The contrast between the dark rich upperparts and white underparts is also well marked in hoyti. On both alpestris and flava streaking breaks away from the lower edge of the breast band, but, given good views, they can be seen to be neat dark triangles or arrowheads on alpestris, and less triangular, more diffuse and smudgy on flava.

DS comments, "Underparts - Again, on average, alpestris is indeed warmer toned on the flanks, cleaner white below and shows a neater pectoral band as compared to the average flava, but once again there was much overlap in the specimens."

In summary, following completion of the post-breeding and post-juvenile moult, alpestris is darker above and whiter below than flava, which is paler, slightly greyer or sandier above, and more dingy below. The crown and upperparts are more broadly streaked; the streaks below the jugular band are darker and neater; the remiges are blacker; the rufous on the coverts more pinkish compared to the more ochrous-rufous of flava. In all, alpestris seems a more contrastingly marked bird with neater, stronger markings. The Nearctic form hoyti breeding to the west of nominate alpestris is quite similar and intergrades between them occur. Typically, it differs in having less yellow on the face, an even richer pink element to the slightly paler upperparts, and a slightly longer and more pointed bill.

DS comments, "As far as I can see we saw the same bird, looked at the same skins and came to different conclusions."

Distribution and variation

A host of subspecies (about 36 depending upon which authority you choose) extend across Europe, North Africa, Asia and North America, and one form in South America. Of these, the Scilly lark was most likely to be of one of the North American subspecies, but few observers at the time were familiar with the suite of features that characterise alpestris, and indeed forms other than flava, to say with certainty that this form was involved.

Palearctic Forms
Within the Palearctic region alone, Vaurie (1959) recognises 14 races, and recently Roselaar (1997) has described an additional subspecies, E.a. kumerloevei from western Turkey. Examination of specimens makes it clear that some of these forms intergrade, making identification and separation of races difficult.

Within the Palearctic, these 15 races fall into three clearly defined groups. Two races, flava of arctic Eurasia and atlas from the mountains of North Africa form the western group and typically show darker upperparts and a distinct yellow facial appearance. A further five races resembling penicillata are confined to southeast Europe and the Middle East, and are characterised by the black of the mask joining the sides of the breast band, leaving a variable pale yellow or white chin, throat and facial colour. The third group comprising the remainder originate from central Asia. These birds lack all traces of yellow and are generally larger and paler than the western races, ranging between the smaller brandti from the steppes of central Asia to the large form khamensis from the Tibetan plateau.

List of Palearctic forms
Only two Palearctic races of Shore Lark show significant amounts of yellow on the face: flava, breeding from the mountains of southern Norway (and occasionally Scotland) north and east across the tundra of arctic Europe and Siberia east to at least 181º E in the Anadyr region; and atlas, confined to the mountains of North Africa.

In southeast Europe and Turkey, the distinctive races balcanica and penicillata exhibit a variable facial colour, appearing whitish in some birds and washed yellow in others. However, in these two races along with kumerloevi, bicornis and albigula, the black ‘mask’ joins with the sides of the black breast patch (‘jugular band’ as Vaurie (1951) describes it), leaving only a small pale throat patch.

To the east, the breeding ranges of a further eight races extend across the steppes and mountain ranges of central Asia to eastern Mongolia, south into northern Iran and Kashmir, and east across the Tibetan plateau to Shanxi province in central China (Vaurie, 1959, Cheng, 1987). Of these, the wide-ranging brandti from the steppes of central and eastern Asia resembles flava in size but is paler and greyish pink above, and the yellow tones of the face are replaced with white. The remaining seven races are restricted to the Tibetan plateau and adjacent arid grasslands and mountain ranges. They are surprisingly distinctive and form a recognisable grouping characterised by their large size, white facial appearance and variable pale vinaceous or grey wash to the upperparts. They range from the large khamensis of south-east Tibet, to the very pale and smaller argalea of Kashmir and Xinjiang region of China. Longirostris closely resembles khamensis, but has a long, strong bill up to 4 mm longer than other taxa.

The following list of forms and their breeding distribution is largely based upon Peters’ Checklist of Birds of the World (1931). The breeding habitat is almost exclusively mountainous areas; in winter a number of races form nomadic flocks that roam across a wide area. The wintering of flava in Britain is said to be a relatively recent phenomenon, dating from c.1870, a pattern mirrored by Germany.

1 flava - mountains of southern Norway (and occasionally Scotland) north and east across the tundra of arctic Europe and Siberia east to at least 181º E in the Anadyr region.
2 atlas - confined to the mountains of North Africa.
3 balcanica - southeastern Europe, including Bulgaria and northern Greece.
4 kumerloevei - eastern Turkey.
5 penicillata - mountains of Asia Minor, Caucasus and east to western Iran.
6 bicornis - southern Asia Minor, including Lebanon and northern Israel (breeds on Mount Hermon).
7 albigula - mountains of northern and eastern Iran, Afghanistan, Tien Shan and western Xinjiang.
8 argalea - Kashmir north to the Kun Lun mountains in Xinjiang, China.
9 teleschowi - southern Xinjiang to the east of argaleus into the deserts regions centred on Lop Nor.
10 przewalskii - north-western Qinghai including the southern part of the Zaidam depression.
11 nigrifrons from eastern Qinghai and north Gansu.
12 longirostris from the north-western Himalayas between the Karakoram to Zanskar but to the south and east it intergrades with elwesi.
13 elwesi from eastern Kashmir east through Sikkim to southern Tibet, north to the upper reaches of the Yellow and Yangtse rivers.
14 khamensis from the south-eastern Tibetan plateau.
15 brandti - steppe and mountains, east of the Volga to western Mongolia, northern China, the Gobi, to northern Gansu.


Nearctic and South American Forms

In North America, Pyle et al. (1987) divide Horned Lark into three groups, totalling 21 races. The northern and eastern group consisting of five forms, including alpestris and hoyti, are ‘dark’ and of variable size, with yellow on the face, and resemble flava quite closely. A second group of ten pale subspecies occur in the drier, arid regions of western and central USA: typified by the very grey, north-western form arcticola from British Columbia, Nevada and Montana, and leucolaema, grey but well-streaked from Texas, New Mexico and Arizona. The western grouping comprises six small races ranging from rubea, a rich, dark and well-streaked form from the Sacramento Valley, northern California, to the pale and pink adusta. Five subspecies, including the small and chunky oxacacae and chrysolaema, occur in Mexico and one race, the enigmatic peregrina, breeds outside the Holarctic region in the Andean grasslands above 2000 metres, south of Bogota, Columbia.

List of Nearctic and Neotropical forms
Subdivided into three groups by Pyle (1998): six Western, rufous forms; ten pale Western forms; four dark eastern forms. Many forms are poorly differentiated, restricted to small geographical areas; most forms are largely sedentary or move short (altitudinal) distances, some such as leucolaema and enthymia have large latitudinal breeding distributions with northern birds wintering in the southern breeding range, but the northern forms of alpestris, hoyti, arcticola and praticola migrate further. The North American races appear to have occupied a larger range of habitats than the Palearctic forms, from coastal plains and islands to more typical mountainous habitat, presumably in the absence of other lark species.

1 alpestris - eastern Canada, from southeastern Baffin Island and northern Labrador south and east to Newfoundland (and reportedly Greenland).
2 hoyti - central Canada, from the western shore of Hudson Bay and Southampton Island west to the mouth of the Mackenzie River; also northern Alberta and Manitoba.
3 giraudi - coastal region of Texas into northern Mexico.
4 praticola - southwestern Manitoba, southwestern Quebec south to eastern Kansas east to West Virginia and North Carolina.
5 strigata - southwest British Columbia, Washington and Oregon.
6 actia - Californian coast from Humboldt County to Baja California (intergrades with rubea and ammophila).
7 insularis - islands off the coast of California.
8 sierrae - localised in northeastern California (southern part of Cascade Range and northern Sierra Nevada).
9 rubea - Sacramento valley, California.
10 adusta - southern Arizona and southwestern New Mexico.
11 arcticola - northern Alaska south to the high Mountains of British Columbia and Washington
12 alpina - restricted to summits of Mt Rainier and Mt St Helens, western Washington.
13 ammophila - Amargosa and Mojave dseserts of southwest Nevada and southeastern California.
14 leucansiptila - Colorado Desert.
15 merrilli - central British Columbia, south to northern California.
16 lamprochroma - southeastern Oregon, southwestern Idaho, northeastern California to western Nevada (intergrades with utahensis).
17 utahensis - southern Idaho south to Nevada and western Utah.
18 leucolaema - stretches from southern Alberta in the north, through western and central Montana, Wyoming, to central Colorado, northern New Mexico and northwestern Texas.
19 occidentalis - north and central Arizona east to northern New Mexico.
20 enthymia - stretches south from central Saskatchewan through eastern Montana, eastern Wyoming, to southern Texas and western Oklahoma.

There are a further five forms breeding in Mexico.

21 enertera - west-central Baja California and coastal islands.
22 aphrasta - northern Mexico (Chihuahua and Durango).
23 diaphora - eastern Mexico.
24 oaxacae - southern Mexico
25 chrysolaema - southern part of Mexican plateau.

In South America, only one form occurs, confined to the grasslands near Bogata, Colombia.

1 peregrina

Movements and vagrancy
Only the northerly breeding races, including nominate alpestris and flava from northern Eurasia are migratory outside the breeding season. The remainder, including many of the Asian and American forms, are resident or form nomadic flocks outside the breeding season.

The most likely of the North American forms to occur in Britain is alpestris, which breeds from northern Quebec, through Labrador to Newfoundland (and reportedly Greenland) moving south or south-east to winter on the east coast of the USA from Massachusetts south to South Carolina and Bermuda. The more westerly race, hoyti breeds in the interior of arctic North America, including the Churchill area of Manitoba, is also a long distance migrant, some also winter on the East coast of the USA, and could conceivably occur in Europe.

Pyle et al. (1987) discuss vagrancy of flava to the Aleutian Islands, and Gibson and Kessel (1998) list it as a casual fall migrant in western and southern Alaska on the basis of five specimens. In addition, there have been further sight records (e.g. on Gambell, Saint Lawrence Island, Alaska, in the northern Bering Sea, from 4-10 September 1999, Paul Lehman pers comm.).

Movements of the central Asian races outside their known range is poorly documented. Brazil (1991) mentions brandti may have occurred once in Japan in May 1987, where flava is known as a rare but regular winter visitor. Westward vagrancy by the Asian forms is undocumented, but with both White-winged Lark Melanocorypha leucoptera and Black Lark M yeltoniensis from the steppes of central Asia having occurred in Europe, the future occurrence of brandti from the same region, or even one of the more easterly forms, remains a possibility.

Brian Small (brianjsmall AT aol.com)
December 2001

Acknowledgments
Peter Kennerley for extensive help with the text and study of specimens. Robert Prys-Jones at BMNH, Tring for allowing access to specimens.


References
Cheng, T.H. 1987. A Synopsis of the Avifauna of China. Science Press. Beijing.
Cramp, S. et al. (ed.) 1988. The Birds of the Western Palearctic Vol. V. OUP.
Garner, M. 1999. An interesting Shore Lark in Ireland. Birding World 12: 152-154.
Pétursson, G. and Ólafsson, E. 1999.
A probable Northern Horned Lark in Iceland, Birding World 12: 375-376.
Pyle, P., Howell, S.N.G., Yunick, R.P., and DeSante, D.F. 1987. Identification Guide to North American Passerines. Slate Creek Press, California
Vaurie, C. 1951. A Study of Asiatic Larks. Bull. Amer. Mus. Nat. Hist. 97. New York.
Vaurie, C. 1959. The Birds of the Palearctic Fauna. A Systematic Reference. Vol. II. Order Passeriformes. H.F. & G Witherby, London.
Gibson, D.D. and B. Kessel 1997. Inventory of the species and subspecies of Alaska birds. Western Birds 28:45-95.
Roselaar, C.S. 1995. Songbirds of Turkey, an atlas of boidiversity of Turkish passerine birds. Haarlem.
Sealy, S.G. 1968. An addition to the avifauna of North America: Eremophila alpestris flava. Auk 85:511.