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 11.1 in January 2021) 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. 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.
Unfortunately, all but two of the original type specimens were destroyed in an earthquake and fire at Ashkhabad but Loskot (2002) provided useful comments from the type description of Shestoperov (1937), including that the upperparts were 'olive grey-brownish with barely visible greenish touch' and the underparts 'whitish, especially pure white in the middle of belly and on under tail coverts', differing from abietinus 'mainly in an absence of yellow streaks on the underparts' and from fulvescens 'in the more greyish upperparts'. Two surviving specimens from the type series had been brought to ZMMU by Dementiev, who had examined the type series and noted that their upperparts were more greyish than in abietinus (Dementiev 1948). Loskot designated one as the lectotype, commenting that it was ‘.. in good condition and has all characters mentioned in the original description of Ph. c. menzbieri’. However, the paralectotype he concluded was not attributable to menzbieri and was probably a migrant of the ‘fulvescens’ type.
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. 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 more 'green' on the upperparts than caucasicus seems unexpected, given the comments of Loskot and the details of the type description of Shestoperov that the 'greenish touch' on the upperparts of menzbieri was 'barely visible'. 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.
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.
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. At that time, a clear image of the precise distributions, the appearances of, and distinctions between, the southern races were not forthcoming from the existing literature. 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 remained 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 regarded as Kopet Dagh in Turkmenistan) - see Fig. 1 above. 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. The Armenian birds were equated with caucasicus but those in Iran were left indeterminate between caucasicus or menzbieri, as the distinguishing features and precise ranges of these two forms were inadequately defined.
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.
Figure 2 below shows the ranges of the Chiffchaff complex as depicted by Raković et al. in 2019, based upon genetic clades.
'Ranges of Common Chiffchaff subspecies, sample localities and mtDNA clades', from Raković et al. (2019).
Given the validity of Raković et al.'s conclusions, the Elborz birds encountered in April 2017 would be 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.
© 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 distinct 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 diffusely and inconspicuously 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. A deficit of olive and yellow in the body plumage but combined with evident olive-yellow fringes to the flight feathers is no doubt the source of analogies which have been made with 'fulvescens', with which menzbieri has at times been included historically. There is a suggestion of 'fulvescens' in the hue of the upperparts but with a greyer tinge. However, the Iranian chiffchaffs have much whiter underparts (lacking the strong buff wash on the flanks of tristis s.l.). Viewed in profile or from below, the 'whiteness' of their underparts is 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). Although exhibiting a more saturated brown hue to their upperparts, these lorenzii converged more with tristis than did the Common Chiffchaffs.
Thus, the appearance of the Elborz Chiffchaffs conformed well with key features attributed to menzbieri by Shestoperov (1937), Marova & Lenovitch (1997) and Loskot (2002). Above all, the predominantly white appearance of their underparts sets them aside. Combined with a grey tinge to their upperparts, they exhibit plumage 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. However, the majority of abietinus are very similar to collybita (as emphasised by Svensson 1992 and Shirihai & Svensson 2018). Conversely, this appearance, especially the whiteness of the underparts, is a striking and consistent aspect of the Elborz and the Caucasian birds, which also have tristis-like calls.
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, with position providing soft shade and avoiding over-illumination or 'burn out'. The distinctive white ground-colour is thereby confirmed.
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 characters noted for menzbieri 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, somewhat h-shaped, introductory notes. These also appear in the sonograms of caucasicus by J. Martens and menzbieri by I. Marova & P. Tomkovitch but those in the Kelardasht sonogram have a terminal component descending to a lower frequency. 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, eighth and twelfth 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 most 'emphatic' note, with a more rounded vowel sound ('choiff' rather than 'chaff'), 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 has a more even sound than the song recorded in Iran in April 2017. However, they share the simple introductory notes (with a pronounced descending terminal stroke in the sonogram). The sonogram shows several further notes of a basically similar structure including, at positions eight and nine, a note with a rising appendix positioned wholly above the base frequency of the initial downstroke. However, the rising appendix appears relatively even, lacking a pronounced 'saw-tooth' structure. Recording circumstances (distance etc.) will undoubtedly affect sonogram nuances but, listening to the songs from Iran and Armenia 'back-to-back' <here>, the 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. As the Vorotan Valley is in the region where the ranges of caucasicus and menzbieri converge in the maps presented by Raković et al. (2019), this warrants further investigation based upon additional recordings of menzbieri from Kopet Dagh and caucasicus from Georgia.
Despite these points of difference, the note-structures of the Iranian and Armenian birds also have points of similarity. However, 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. The second call attributed to caucasicus in sonogram 'k' is especially even in pitch ('straight' / 'flat') but the calls recorded at Vorotan in Armenia in May 2018 also have a very even pitch. Each would be effectively indistinguishable from tristis. The calls attributed to menzbieri in sonogram 'l' and the calls recorded at Kelardasht and Kiaser in Iran in April 2017 have a profile which is relatively straight and tristis-like initially but rises and then falls slightly towards the end. The slight rise and fall of these calls hints at a subtly 'inflected' 'sweeoo' sound but with the 'inflection' well towards the end of the call rather than centrally. However, whether this subtle difference from the right-hand call attributed to caucasicus in sonogram 'k' is consistent remains to be confirmed. The very straight call attributed to caucasicus is from a recording made by J. Martens at Alamdeh (Royan), Iran, which is in the same general region as Kelardasht. Thus, it appears that calls which are straighter throughout their length and calls which rise and fall slightly towards the end have both been recorded in the same general area of the Elborz. This highlights questions over both the precise distribution of the two taxa and the extent of individual variation in calls within each taxon (cf. the variation in tristis). In the field, all these calls would be effectively indistinguishable from tristis. 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. Further documentation of this call from Georgia and southern Russia is clearly required.
The calls in the menzbieri sonogram provided by Helbig et al. are unequivocally menzbieri, based upon a recording at Kopet Dagh by Irina Marova, and these calls are a good match with those recorded at Kelardasht and Kiaser during April 2017. More recently, Cedric Mroczko placed on xeno-canto (xc513431) recordings of chiffchaffs from Alagol, NE Iran, on the border with Turkmenistan. The breeding form here would also near-certainly be menzbieri but, as the recordings were made in November, there remains a possibility that some other taxon was involved. A sonogram shows a very clearly-marked terminal 'rise and fall' (Figure 7), even more pronounced than in the calls recorded in the Elborz at Kelardasht and Kiaser. The shape in the Elborz sonograms and those from calls at Kopet Dagh recorded by Irina Marova might be interpreted as intermediate between this pronounced 'rise and fall' profile and the flatter calls associated with caucasicus. See also addendum below.
Longer series of recordings from Georgia, southern Russia, throughout Iran and the Kopet Dagh area of Turkmenistan are required, to clarify the characteristics and variation of calls from the heartlands of currently-designated caucasicus, the heartlands of menzbieri and regions in-between. However, there is a prima facie case that a call with a 'terminal arch' may be indicative of menzbieri.
Chiffchaff 'tret' calls
In an intriguing paper, Ivanistkii et al. (2020) have reported that the short, dry 'tret' calls, which Chiffchaffs interpose between the strophes in their songs, also differ between the various taxa of the chiffchaff complex (including here the 'Mountain Chiffchaffs' lorenzii and sindianus). The exception was that the 'tret' calls of collybita and abietinus were indistinguishable and there was a proviso over brevirostris, which (at least during their study) used such calls relatively infrequently. The authors suggest that the 'tret' calls of abietinus and caucasicus are sufficiently distinct to provide an aid to clarifying their geographical distributions. (Also fascinating is their finding that the 'tret' calls of tristis differ between central Siberia and NE Yakutia.)
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 Chiffchaffs observed in N. Iran in April 2017 would be 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 here may contribute to discussions of the characters, distribution and taxonomy of the southern subspecies of Common Chiffchaff. Common Chiffchaffs in Armenia and in the Elborz Mountains of Iran, at least as far east as Kiaser, share brown but grey-tinged upperparts and distinctly whitish underparts. Olive is also apparent on the upperparts but is restricted and comprises scattered streaking rather than an overall suffusion. The upperparts of the Armenian birds appeared a little more olive (especially considering the notionally fresher plumage of the Iranian birds, being in April, compared with May for the Armenian individuals). The decidedly whitish ground colour of the underparts is common to the Chiffchaffs in both locations and was among the most distinctive features in the field. Yellow streaking is very limited and only detected at close range. 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 in the type description (Shestoperov 1937) and in discussions by Watson (1962), Marova & Leonovich (1997) and Loskot (2002). Recordings of songs and calls from Armenia and the Elborz Mountains of Iran (east to Kiaser) and are generally in keeping with sonograms published by Helbig et al. (1996) and Clement et al. (1998) but there are subtle differences in the sonograms from the two regions. A note with a rising appendix, positioned wholly above the base frequency of the initial down-stroke, is distinctive in sonograms of songs of both forms. However, the rising appendix has a distinctly 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. The calls of the Chiffchaffs in both Iran and Armenia are very similar to the call of tristis. Although still sounding similar to tristis, sonograms reveal a 'terminal arch' in calls from Chiffchaffs in Iran, across the wider range attributed to menzbieri by the genetic clades identified by Raković et al. (2019). 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.
There is some plumage convergence with 'greyer and whiter' individuals attributed to the east of the range of abietinus but, 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 may be subtle, to discard taxonomic recognition of the southern subspecies would under-represent the 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 is currently hypothetical and genetic data is required. Individuals observed in Kuwait during Nov / Dec 2013 shared certain plumage features with the Elborz birds but appeared less grey-tinged on the upperparts and less white below. Their calls too rise and fall towards the end, producing a 'terminal arch'. This profile is more-marked than in sonograms from recordings of the Elborz birds (and those by Irina Marova from Kopet Dagh) but is approached by the recordings by Cedric Mrozko from NE Iran. See <here> for photos, sound-recording and sonogram of Kuwaiti birds. 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. Does this 'terminal arch' call distinguish between menzbieri and caucasicus? Is it 'mainstream' or an 'alternative' call? 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, Martin Collinson for clarifying certain genetic issues in that paper and Daniel Duff for more-general discussion of the potential traits of southern forms of Chiffchaff.
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