Southern forms of Chiffchaff Phylloscopus collybita : observations from Iran and Armenia.
© Ali Alieslam
Common Chiffchaff Phylloscopus collybita (probably menzbieri - see text), Kelardasht, N. Iran, April 2017.
Despite the advances afforded by molecular genetics, taxonomy remains an inexact science. Opinions vary, not only on species and subspecies boundaries but over the appropriate criteria to be employed in reaching taxonomic decisions. This situation is nowhere better exemplified than in the Chiffchaff complex. The BOU now follows the IOC World Bird List (at version 9.1 in Jan. 2019) which recognises six subspecies of Common Chiffchaff Phylloscopus collybita viz. P. c. collybita, P. c. abietinus and P. c. tristis in the northern part of the species’ range and P. c. brevirostris, P. c. caucasicus and P. c. menzbieri farther south (Figures 1 & 2). Hereafter, each taxon - including also (Caucasian) Mountain Chiffchaff P. sindianus lorenzii - is generally referred to succinctly by its subspecific name.
Based upon mitochondrial DNA (mtDNA), morphology and vocalisations, Helbig, Seibold, Henning, Schottler & Wink (1996) and Clement, Helbig & Small (1998) greatly clarified understanding of the taxonomy of the Chiffchaff complex. However, the distinguishing features of the southern forms of Common Chiffchaff, brevirostris, caucasicus and menzbieri, remain far from firmly established, while Helbig et al. found the forms brevirostris and caucasicus to be virtually indistinguishable genetically. All three southern taxa have been described as close in appearance to abietinus (e.g. Clement et al. 1998). Other accounts suggest that, as a group, the southern forms are somewhat intermediate between abietinus and lorenzii but closer to the former, being rather 'browner' than typical abietinus and with reduced yet still-evident olive and yellow hues. However, references to menzbieri frequently acknowledge the lack of current information and an absence of photographs. The songs of the southern subspecies are all variants on the 'chiff-chaff' theme but pace and timbre vary while sonograms reveal distinct note structures. Counter-intuitively, the calls of the southern forms do not match the rising 'huit' call of collybita and abietinus but are very similar to the 'straight', plaintive 'eeep' call of tristis. Of the Chiffchaff complex as a whole, Helbig et al. wrote : '... vocal differences, like mitochondrial DNA sequences, reflect evolutionary differentiation within the chiffchaff complex over long time spans much better than does morphology, which is relatively uniform'.
In general, comments on the appearance of menzbieri presented in European literature are inconsistent and third-hand, based upon earlier accounts deriving from the type description (Shestoperov 1937) or Dementiev & Gladkov (1954, English translation 1968), for example. As the form caucasicus was not described by Loskot until 1991, earlier historical accounts of menzbieri do not mention, yet alone compare, caucasicus. Presumably on the basis of a deficit of olive and yellow, Chiffchaffs from NE Iran to SW Transcaspia (i.e. the range associated with menzbieri) were included in tristis (or ‘fulvescens’) by Vaurie (1959), Williamson (1962) and Cramp et al. (1992), though the last added that it might belong with abietinus. Shirihai & Svensson (2018) also suggested plumage convergence between menzbieri and both 'fulvescens' and eastern abietinus. On distributional grounds alone, that Chiffchaffs from Kopet Dagh and NE Iran belong with tristis seems implausible. Watson (1962), in his paper recommending reinstatement of the name brevirostris for the Chiffchaffs breeding in northern Turkey, provided a table of comparative characters of brevirostris, abietinus, menzbieri and lorenzii.. The distinguishing features included in the table are very rudimentary but the word 'brown' is allocated only to the upperparts of lorenzii. The description for the upperparts of abietinus is 'greyish green' and for brevirostris 'greenish grey' (implying that brevirostris is the greyer form). Watson described the upperparts of menzbieri as 'mostly grey, tinged greenish' [my emphasis] but it seems unlikely that this was based upon examination of extensive original material. He noted a west-to-east reduction in lipochrome pigment (as in the northern forms), resulting in whiter underparts, with reduced yellow streaking. The underparts of menzbieri he described simply as: 'white, no yellow'.
More recently, Copete & Lopéz (2013) and Shirihai & Svensson (2018) have questioned aspects of the prevailing taxonomy of Common Chiffchaff. Both sets of authors suggested, on the basis of morphology, that brevirostris be subsumed with collybita. Copete & Lopéz noted that photos of type specimens of caucasicus provided to them by Vladimir Loskot exhibited upperparts similar to abietinus but 'yellow much more clearly present on the edge of the wing, lower parts clearly whiter'. The legs were also noted to appear densely black, more so even than in tristis. They considered that the material they had examined showed a consistent appearance but concluded that examination of a longer series was required to confirm the validity of caucasicus. Despite the near-identical mtDNA of brevirostris and caucasicus, Shirihai & Svensson (2018) - who advocated merging brevirostris with collybita - suggested that caucasicus be merged with abietinus. While retaining menzbieri, at least pro tem, Shirihai & Svensson also raised doubts over that taxon's validity. This comes close to negating the entire group of southern subspecies. As the appearance of typical abietinus is also emphasised as very close to that of nominate collybita (e.g. Svensson 1992), functional differences in appearance among the Common Chiffchaff races are inferred to be very subtle indeed (with a more-singular image emerging only for 'classic' tristis). In contrast with other subspecies, Copete & Lopéz (2013) concluded that they could not comment on the morphology of menzbieri, as there was a lack of accessible data.
One of the very few accounts based upon first-hand observations of menzbieri in the Kopet Dagh, from where the original 'type specimens' were obtained, is that of Marova & Leonovich (1997). They noted that this region is rarely visited by ornithologists and also that the original type specimens were destroyed in a fire. This has no doubt contributed to the dearth of clear documentation in the literature. Discussing distribution, the authors noted that Kopet Dagh was the established range but they included citations to menzbieri in the Elborz mountains of northern Iran. They suggested that the Elborz population was probably menzbieri but acknowledged that further information was required. This account provided explicit comments on the comparative appearance of menzbieri and caucasicus. It is in Russian but includes an English summary, from which the following is an extract (verbatim):
'Contrary to Ph. c. abietinus, Ph. c. menzbieri has only a trace of yellow colour on the breast, white belly and white undertail coverts. From Ph. c. caucasicus it differs both in the bright yellow colour of the axillars and the wrist and in the brighter green colour on the back and on the edge of the primaries and tail feathers'. Once again, rather white underparts enter the frame for the southern races but that menzbieri exhibits slightly more olive and yellow than caucasicus might be unexpected, given the general depletion of these hues from west to east among the Chiffchaff complex. However, Irina Marova (in litt.) states that, while the appearance of menzbieri has little in common with tristis or lorenzii (contra some earlier literature), the differences between menzbieri and caucasicus noted by Marova & Leonovich (1997) are relatively small.
Thus, a clear image of the precise distributions, the appearances of, and distinctions between, the southern races are not forthcoming from the existing literature. The following text is based upon photographs and sound-recordings of Common Chiffchaffs observed at Kelardasht and Kiaser in the Elborz Mountains of N. Iran during April 2017 and in the Armenian Caucasus at Dilijan and the Vorotan Valley during May 2018. Following the taxonomic and distributional data prevailing at the time of these observations, the Armenian birds were equated with caucasicus while those in Iran were left indeterminate between caucasicus or menzbieri, as the distinguishing features and precise ranges of these two forms were inadequately defined. Later examination and comparisons of the sonograms of these Iranian Chiffchaffs with sonograms published by Helbig et al. (1996) and Marova & Leonovich (1997) - see 'Vocalisations' below - suggested a slightly better match with menzbieri rather than caucasicus but this remained tentative.
Subsequently, a more-comprehensive genetic study of the Chiffchaff complex has been published by Raković et al. (2019). This is essentially a genetic study and did not examine morphology or vocalisations. Its findings broadly support the conclusions of Helbig et al. (1996) and the validity of the currently recognized subspecies of Common Chiffchaff, while also describing the genetic makeup of the newly discovered Chiffchaff population breeding at Mt. Hermon, on the border between Lebanon and Syria - see Raković et al. for details. As with Helbig et al., this new study noted that, effectively, brevirostris and caucasicus were genetically inseparable by cytb and, therefore, these were combined as a joint genetic clade. Significantly, a separate clade was identified around Transcaucasia, south and east from, and genetically distinct from, the brevirostris / caucasicus clade. The inference that this clade equated with menzbieri (the only recognised subspecies south and east of 'caucasicus') was supported by the single genetic sample of menzbieri in GenBank. Thus, on geographic and genetic grounds, this Transcaucasus clade was reasonably equated with menzbieri. The authors note that in some taxonomic publications the form(s) of Common Chiffchaff found in southernmost Armenia and northern Iran have been left undefined (e.g. in the Checklist of Birds of the World compiled by Clements et al. 2015) and, to place this new interpretation beyond doubt, a much larger and representative series of genetic material was required from across N Iran and from Kopet Dagh. The implication, however, is that menzbieri extends from southern Armenia (south of Goris), continuously through the Hyrcanian forest of the Elborz mountains of N. Iran and east to Kopet Dagh in Turkmenistan, a much more extensive range than the often-quoted 'isolated range' around Kopet Dagh. Given the validity of Raković et al.'s conclusions, the Elborz birds encountered in April 2017 were menzbieri while those in the Vorotan Valley near Goris in May 2018 were in the region where the ranges of caucasicus and menzbieri converge and appear to overlap (see Figure 2).
Hopefully, the photos and sonograms below, from the Iranian Elborz Mountains and the Armenian Lesser Caucasus, will provide useful supplementary (and relatively 'accessible') reference material on the appearance and vocalisations of the enigmatic Chiffchaff forms inhabiting these areas. If the distribution of menzbieri as inferred by Raković et al. is correct, then plates 2 to 7 below from N. Iran (especially those by Ali Alieslam, Steve Rooke and Robert Tizzard) will help to address the previous dearth of published photographs of menzbieri.
Figure 1 shows the breeding ranges of the southern species and subspecies as depicted by Copete & López (2013) and modified from Handbuch der Voegel Mitteleuropas, Glutz von Blotzheim & Bauer (1991). Of necessity, the ranges shown were no more than approximate, as the full distributions of the southern subspecies of Common Chiffchaff still remain imprecisely clarified (while (Caucasian) Mountain Chiffchaff (lorenzii) certainly has a wider distribution than indicated in Figure 1, e.g. extending into the western Elborz Mountains of Iran). Superimposed on this map are the approximate locations of Kelardasht and Kiaser, in Iran, and Dilijan and Goris in Armenia.
The locations of Kalerdasht and Kiasar, in Iran and Dilijan and Goris in Armenia, superimposed on range map for caucasicus and menzbieri (and other southern forms)
as portrayed by Copete & López (2013) and modified from Handbuch der Voegel Mitteleuropas, Glutz von Blotzheim & Bauer (1991).
Kelardasht is at the eastern extreme of the range depicted for caucasicus in Copete & López (2013) while Kiasar lies close to the western end of the range depicted for menzbieri (its core range being in the Kopet Dagh in Turkmenistan) - see Fig. 1 above. These two locations thus appear to demark an apparent gap in the depicted distributions of the Chiffchaff races but may merely reflect inadequate data. As at April 2017, how far west menzbieri extends was not established. Similarly vague was the true extent of the range of caucasicus along the southern shores of the Caspian Sea. On the basis of range, it was not possible in April 2017 to allocate the Chiffchaffs at Kelardasht and Kiasar to one form or the other.
Subsequently, Shirihai & Svensson (2018) mapped the distribution of menzbieri from Kopet Dagh west through the Elborz to approximately the longitude of Rasht, in the Gilan Province of Iran, but this was provisional. Figure 2 below shows the ranges of the Chiffchaff complex as depicted by Raković et al. in 2019, based upon genetic clades. This map infers an even wider distribution for menzbieri, including Kopet Dagh and through the Elborz mountains of N. Iran and yet farther west into southernmost Armenia (south of Goris according to their text). Following this map, the Chiffchaffs observed in Iran in April 2017 would be menzbieri and those in Armenia in May 2018 in the convergence zone between menzbieri and caucasicus.
'Ranges of Common Chiffchaff subspecies, sample localities and mtDNA clades', from Raković et al. (2019).
© A. R. Dean
Common Chiffchaff Phylloscopus collybita ssp, (probably menzbieri), Kelardasht, Elborz Mountains, Iran, April 2017.
The image above shows a Common Chiffchaff Phylloscopus collybita observed in the central Elborz Mountains near Kelardasht, in northern Iran, during April 2017. The species was quite numerous in light woodland (including oak, hornbeam and hawthorn) at an altitude of around 1500m, a habitat shared with Green Warblers P. nitidus. Chiffchaffs of similar appearance and vocalisations were encountered subsequently in denser woodlands farther east, near Kiasar. Plates 3 to 6 capture their appearance particularly well and I am grateful to Ali Alieslam, Steve Rooke and Rob Tizard for providing their excellent images.
© Ali Alieslam
© Ali Alieslam
© Steve Rooke
© Rob Tizard
© Rob Tizard
Plates 3 to 7. Common Chiffchaffs, c. 1500m in Elborz Mountains near Kelardasht, Iran, April 2017
The appearance of the Elborz Chiffchaffs differed in several respects from that of typical abietinus. Their upperparts exhibited a strong grey component (greyer on the mantle, somewhat browner on the crown). Their underparts were conspicuously white (though slightly sullied), lacking field-evident yellow anywhere in the body plumage (though with a tinge at the front of the upper eye-ring). The upperparts away from the crown were streaked with olive and there were well-developed olive-yellow fringes to the remiges and rectrices. The legs and feet were decidedly black while there was a conspicuous pale base to the lower mandible. Often the plumage appeared rather pale overall but, at close range and in duller light, a browner aspect to the upperparts was apparent. Thus, viewed dorsally in duller light conditions, they could be taken for abietinus but, viewed in profile or from below, the 'whiteness' of their underparts was consistently distinctive.
At higher altitudes above 2500m, on relatively bare mountain slopes with scrub and isolated clumps of small trees, these rather 'grey and white' Chiffchaffs were replaced by (Caucasian) Mountain Chiffchaffs P. lorenzii which, even in the brightest light, exhibited much browner upperparts (lacking olive), a distinctive fulvous-buff wash on the breast, 'plain' wing and tail edges (lacking the prominent olive-yellow fringes of the Common Chiffchaffs) and a more-prominent supercilium (together with subtly different vocalisations).
To my eye, except for a deficit of yellow, the Iranian birds did not suggest classic tristis and they were paler, less 'tan-brown-and-buff' than even 'fulvescens' (see above). While lorenzii encountered in Iran and Armenia certainly draw comparisons with classic tristis (they share a brown aspect and a lack or deficit of olive and yellow hues) this cannot be said of the Common Chiffchaffs. Above all, the predominantly white appearance of their underparts sets them aside. Combined with a grey tinge to their upperparts, this produces some convergence with the 'grey and white' Chiffchaffs discussed extensively elsewhere on this website, As noted there, while 'grey and white' Chiffchaffs may include intergrades between abietinus and tristis, it is also likely that a minority of abietinus from the east of its range naturally exhibits a relatively grey and white appearance. That some abietinus are greyer and whiter than typical individuals may seem in accordance with the decision of Shirihai & Svensson (2018) to synonymise caucasicus with abietinus and to question the validity of menzbieri. However, the majority of abietinus are very similar to collybita (as emphasised by Svensson 1992 and Shirihai & Svensson 2018) and only a minority exhibits evidently greyer and whiter livery. Conversely, this appearance, especially the whiteness of the underparts, is a striking and consistent aspect of the Caucasian and Elborz birds. It would seem more appropriate to say that some abietinus (a minority) approach the 'greyer and whiter' appearance of these southern forms rather than negate the southern forms on the basis that their appearance is approached by a minority of abietinus.
In May 2018, Common Chiffchaffs were observed, photographed and sound recorded in the Dilijan region and in the Vorotan Valley of Armenia. Again, Green Warblers were found in the same habitats while lorenzii overlapped in altitudinal range. At the time these Armenian birds were assumed to be caucasicus but the recent genetic studies by Raković et al. indicates that menzbieri extends into Armenia south of Goris and that Transcaucasus and especially the Lesser Caucasus comprise a transition zone between caucasicus and menzbieri (see Figure 2).
© A. R. Dean
© A. R. Dean
© A. R. Dean
Plates 8 to 10. Common Chiffchaffs, near Dilijan, Armenia, May 2018.
Note basic similarity of these Chiffchaffs in Armenia to Chiffchaffs in Iran in plates 2 to 7 but with olive more apparent on upperparts.
If valid, this implies that Armenian Chiffchaffs are slightly more olive, not less, than northern Iranian Chiffchaffs (c.f. Marova & Leonovich 1997)
© A. R. Dean
Common Chiffchaff, near Dilijan, Armenia, May 2018. Close-up of wings showing contrasting yellowish fringes to flight feathers.
© A. R. Dean
Common Chiffchaff, near Dilijan, Armenia, May 2018.
Close-up of underparts, showing their distinctive white ground-colour.
Being in soft shade, the underparts are not overly-illuminated nor 'burnt-out' and their basic 'whiteness' is evidently genuine.
The distinctly white-looking underparts, well-defined olive-yellow fringes to flight-feathers and 'densely black' legs accord with the impressions noted by Copete & López (2013), based upon photographs of type specimens of caucasicus (provided to them by Vladimir Loskot). However, they are also consistent with the characters noted for menzbieri by Watson (1962) and Marova & Leonovich (1997) and how closely these features may be shared by the two forms remains to be resolved.
© A. R. Dean
Common Chiffchaff, Vorotan Valley near Goris, Armenia, May
2018. Chiffchaffs 'south of Goris' are part of the Transcaucasus clade equated
by Raković et al. (2019). The individual above (plate 13) appears very similar to the Chiffchaffs in N. Iran in plates 2 to 7, including little olive in the upperparts
as well as a deficit of yellow below. However, north from Goris, the ranges of menzbieri and caucasicus apparently converge (Raković et al. - see Figure 2).
Helbig et al. (1996) and Clement et al. (1998) provided sonograms of the songs and calls of all subspecies. These are used to provide a platform by which to evaluate sound-recordings made in Iran in April 2017 and Armenia in May 2018.
A recording of the song from Kelardasht, Iran, can be heard <here>. Compared with collybita / abietinus, the notes have a harder, 'punchier' and more staccato delivery. A sonogram appears as the upper graph in Figure 3, with comparative sonograms of caucasicus and menzbieri from Helbig et al. presented below.
Sonogram of Chiffchaff song recorded at Kelardasht, in Elborz Mts,
Iran, April 2017
compared with sonograms published by Helbig et al.(1996) and Clement et al. (1998).
The sonogram from Kelardasht shows simple introductory notes which also appear in the sonograms of caucasicus by J. Martens and menzbieri by I. Marova & P. Tomkovitch. Subsequent notes are more complex but each note-structure in the Iranian recording from April 2017 has a close match in the sonograms of menzbieri presented by Helbig et al. (1996). Similar though less precise matches for many notes can be found in Helbig et al.'s sonogram of caucasicus. The exception lies in the note found at the fourth, sixth and eighth positions in the Iranian recording from 2017, position six in Helbig et al.'s first sonogram of menzbieri and positions five and seven in their second sonogram. This note includes a rising 'saw-tooth' flourish or appendix positioned wholly above the base of the initial down-stroke. This is the 'hardest' note and is evident to the ear in the sound-recording from 2017. In the sonogram for caucasicus provided by Helbig et al. this note is not present. (At first sight, notes six, eight and thirteen may hint at a similar structure but in each of these notes the appendix is positioned lower and contains a gap, which indicates that a lower-frequency downward-extending 'spike' has been truncated i.e. these notes are in fact notes of the type exhibited at positions three, four and five in the first of Helbig et al.'s menzbieri sonograms). At the time of the recording (April 2017), this 'saw-tooth appendix' suggested that the song of the Elborz birds may favour menzbieri. That the Elborz Chiffchaffs are menzbieri is now supported provisionally by the genetic studies of Raković et al. (2019).
A recording of the song from the Vorotan Valley, Armenia, can be heard <here> while a sonogram is provided in Figure 4.
Song of Chiffchaff in Vorotan Valley, Armenia, May 2018.
The recording from May 2018 in the Vorotan Valley of Armenia shows a basically similar structure of notes to those from Iran in April 2017. At positions eight and nine, Figure 4 includes a note with a rising appendix positioned wholly above the base frequency of the initial downstroke, albeit with a less pronounced 'saw-tooth' structure. At the time, the Armenian birds were assumed to be caucasicus as currently designated, with the implication that such a rising appendix was not restricted to menzbieri. However, the genetic findings of Raković et al. suggest that menzbieri too may occur in southern Armenia, with an area of transition around the Transcaucasus (Figure 2). Recording circumstances (distance etc.) will undoubtedly affect sonogram nuances but, listening to the songs from Iran and Armenia 'back-to-back' <here>, this saw-tooth note is more emphatic in the song of Iranian birds while the corresponding note is relatively subdued in the Armenian birds. Sonograms of menzbieri and caucasicus in Marova & Leonovich (1997) lend some support to a more-even, less saw-toothed appendix in caucasicus. This warrants further investigation, based upon additional recordings of menzbieri from Kopet Dagh and caucasicus from Georgia.
However, while the note-structures of the Iranian and Armenian birds are comparable (though not wholly identical), they differ significantly from the note-structures in the sonograms of brevirostris by P. S. Hansen from Ulu Dagh, Turkey, published by Helbig et al., and in a recording by Manuel Sanchez of brevirostris from Istanbul, available on xeno-canto as XC142271. The song of brevirostris is dominated by a single, repeated note with 'double spurs', as in Figure. 5.
Figure 5. Sonogram of brevirostris song by P. S.
Hansen from Ulu Dagh, Turkey.
Reproduced from Helbig et al. (1996) & Clement et al. (1998)..
Grishchenko et al. (2016) analysed the songs of a newly-established breeding population of Common Chiffchaffs in the Crimea. They concluded that certain elements in the song were shared with caucasicus but not with abietinus and concluded that the Crimean population originated from caucasicus. Using the sonograms published in 1996 by Helbig et al. (and Clement et al. in 1998) they also concluded that menzbieri (and brevirostris too) contained subspecifically distinct elements. Unfortunately, they did not elaborate or include illustrative, annotated sonograms of all forms, so independent evaluation is not possible currently.
A recording of the call of Chiffchaffs at Kelardasht, Iran, in April 2017 can be heard <here>.
A recording of the call of Chiffchaffs in the Vorotan Valley, Armenia, in May 2018 can be heard <here>.
Figure 6 provides sonograms of the calls recorded in Iran and Armenia while, for comparison, sonograms of brevirostris, caucasicus, menzbieri and tristis are included, reproduced from Helbig et al (1996) and Clement et al. (1998).
Clearly, apart from the first call in Helbig et al.'s sonogram 'k', all these calls are relatively straight ('flat') and resemble the call of tristis. There are subtle differences in sonograms but whether they are consistent remains speculative. One of the sonograms of calls attributed to caucasicus in Helbig et al. and in Clement et al.(1998) was from a recording made by J. Martens at Alamdeh (Royan), Iran, which is in the same general region as Kelardasht. It is not stated on what the diagnosis was based and (following Raković et al.) it may well involve menzbieri rather than caucasicus. The first call in sonogram 'k', recorded at Mount Elbrus in the northern Caucasus by J. Martens (well inside the perceived range of caucasicus) is very different, with a strongly rising terminal pitch. Further documentation of this call from Georgia and southern Russia is clearly required (see also addendum below).
The calls in the menzbieri sonogram provided by Helbig et al. are unequivocally menzbieri, based upon a recording at Kopet Dagh by Irina Marova. They are 'straight' style calls but rise and fall slightly at the end, hinting at a subtly 'inflected' 'sweeoo' sound. The calls recorded at Kelardasht and Kiaser in April 2017 also show this slight terminal 'rise and fall'. Given the rather straighter call from Alamdeh (near Kelardasht) in Helbig et al.'s sonogram 'k', attributed to caucasicus but on location more probably menzbieri (following from Raković et al. 2019), such variations may be no more than individual variation (c.f. the variation in tristis). The sonogram from Armenia in 2018 is also very 'straight' and matches the three calls in the second section of Helbig et al.'s sonogram 'k'. Once again, longer series of recordings from Georgia and southern Russia are required to clarify the characteristics and variation of calls from the heartlands of currently-designated caucasicus.
In conclusion, the songs and calls of Chiffchaffs at Dilijan and Vorotan Valley in Armenia (respectively north of and close to the overlap zone between caucasicus and menzbieri, as inferred by genetic analyses published by Raković et al.) are similar to but not identical to those of Chiffchaffs encountered in the Elborz Mountains of Iran as far east as Kiaser (which are equated with menzbieri via Raković et al.). Further study is required to determine whether subtle differences are within the limits of individual variation in the two regions or whether they are taxonomically significant.
Observations, photographs and sound-recordings of Common Chiffchaffs were made in April 2017 in the Elborz Mountains of Iran (east to Kiaser) and in May 2018 at Dilijan and the Vorotan Valley near Goris in Armenia. Based upon published distribution maps at the time, it was presumed that the Armenian birds would be caucasicus while the Iranian birds were left indeterminate between caucasicus or menzbieri. Armenia and N. Iran 'bridge' the ranges of currently designated caucasicus and menzbieri but their precise ranges remain undefined. Subsequently, genetic analyses conducted by Raković et al. (2019) detected a distinct clade around Transcaucasia, east and south of the brevirostris / caucasicus clade. Although samples throughout N. Iran and Kopet Dagh were still required for analysis, the authors inferred that this clade equated with menzbieri and that the range of this form included not only Kopet Dagh but the entire Hyrcanian forest of N. Iran and into southern Armenia as far as Goris. This implies that the Chiffchaffs observed in N. Iran in April 2017 were menzbieri while those in Armenia in 2018 were from the region where the ranges of caucasicus and menzbieri converge. If indeed the range of menzbieri is so much more extensive than hitherto implied and extends so far west then, presumably, the prospects of extralimital occurrences in the Middle East and parts of Europe are correspondingly enhanced.
It is hoped that the material gathered may contribute to discussions of the characters, distribution and taxonomy of the southern subspecies of Common Chiffchaff. The data support a conclusion that Common Chiffchaffs in Armenia and in the Elborz Mountains of Iran, at least as far east as Kiaser, share grey-tinged upperparts and distinctly whitish underparts. A browner ground-colour to the upperparts emerges in duller light conditions with olive restricted and comprising scattered streaking rather than an overall suffusion. The upperparts of the Iranian birds appeared a tad greyer and colder than those of the Armenian birds at Dilijan, which were a little more olive, especially considering their notionally fresher plumage (being in April, compared with May for the Armenian individuals). The Armenian birds in the Vorotan Valley near Goris were closer perhaps to those in Iran but this requires confirmation (Vorotan birds were seen less closely and in very bright light : the different location and different light conditions engender caution). The decidedly whitish ground colour of the underparts is common to the Chiffchaffs in both locations, with very limited yellow streaking, which is generally undetected under field conditions. The fringes to the remiges and rectrices, however, are distinctly yellowish. The legs and feet are densely black. Such features have been associated with the form caucasicus (Loskot 1991), as discussed by Copete & López (2013), but are also compatible with comments on the appearance of menzbieri included in Watson (1962) and Marova & Leonovich (1997). Recordings of songs and calls from Armenia and the Elborz Mountains of Iran (east to Kiaser) also show a basic similarity, though again there are subtle differences. A note with a rising appendix, positioned wholly above the base frequency of the initial down-stroke, is distinctive in sonograms of both forms. However, the rising appendix has a rather more 'saw-tooth' structure in the Iranian birds' sonograms and a 'straighter', more-even shape in the Armenian birds. Confirmation (or otherwise) of the consistency of this apparent difference is required. Jointly, the songs from Armenia and Iran include characteristic notes not found in the songs of other subspecies, including the form brevirostris found adjacently in northern Turkey. More extensive data from across the entire region is needed to clarify whether the clade identified from Transcaucasia by Raković et al. (2019) does indeed equate with menzbieri and extend from Kopet Dagh in Turkmenistan and across the Elborz mountains of N. Iran into southern Armenia. As a group, the geographical distribution of these southern forms, the 'whiteness' of their underparts, their tristis-like calls and the presence of distinctively-shaped notes in sonograms of their songs set them aside from typical abietinus. While the differences are subtle, to discard entirely taxonomic recognition of the southern races would surely under-represent the true diversity of Phylloscopus collybita.
Chiffchaffs of puzzling identity are also encountered in winter in Kuwait. It has been suggested that they might be menzbieri but the basis for this seems wholly hypothetical. Although they share certain plumage features with the Elborz birds. they are less grey-tinged on the upperparts and less white below, showing restricted yet evident yellow streaking. Their call rises and falls but, compared with the Elborz birds, this is much more accentuated, being distinctly arched and reaching a higher frequency. See <here> for photos, sound-recording and sonogram. At first sight, the sonogram does not match closely any of those published by Helbig et al. and Clement et al. However, the flat opening pitch and marked rise at the mid-way point are a very close match with the first call attributed to caucasicus in sonograms 'k' above. The latter apparently lacks a subsequently descending profile, unless the recording or sonogram are truncated (the terminal fall is relatively faint in some sonograms from Kuwait). Interestingly, on the Finnish 'Tarsiger' website, there is a recording <here> by Timo Janhonen of a Chiffchaff in Azerbaijan, from March 19th 2012, that has a call which sounds near-identical to the Kuwait Chiffchaffs. A prepared sonogram shows the same distinctive shape. The breeding form in Azerbaijan is deemed to be caucasicus but, as with southern Armenia, the genetic clade identified by Raković et al. (2019) suggests that menzbieri must also be considered. Further, the early date of the Azerbaijan recording does not confirm birds established on territory. There were several such birds but Timo Janhonen states (in litt.) that they were in lowland shrubberies and meadows by the Caspian Sea (rather than the forest) and, consequently, it is impossible to know whether they were arriving near their breeding grounds or were migrants en route farther afield. Timo also noted a very similar call <here> on xeno-canto, recorded in Azerbaijan in January 2015 by Steve Klasan, so individuals with this call apparently winter in the region. Is this in fact a typical call of caucasicus? There are still many questions to answer!
I would like to thank Ali Alieslam, Steve Rooke and Rob Tizard for discussions in the field and provision of their excellent photographs of Chiffchaffs in Iran; José Luis Copete and Lars Svensson for comments (in litt.); Irina Marova for comments (in litt.) and for providing a copy of her paper with V. V. Leonovich on menzbieri at Kopet Dagh; Roger Riddington for permission to re-use sonograms published in British Birds; Timo Janhonen for providing information on Chiffchaffs he observed and sound-recorded in Azerbaijan in March 2012; Antero Lindholm for discussions of Chiffchaffs in Georgia and surrounding regions; Marko Raković and his co-authors for providing 'open access' to their paper via the PLoS publishing organisation and Martin Collinson for clarifying certain genetic issues in that paper.
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