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Song of the Dark-throated Thrush Vladimir Yu.Arkhipov, Michael G.Wilson and Lars Svensson 49. Male Dark-throated Thrush Turdus ruficollis atrogularis, Lake Ysyk-Köl, Kyrgyzstan, February 2002. Jürgen Steudtner ABSTRACT The song of the Dark-throated Thrush Turdus ruficollis of the race atrogularis (‘Black-throated Thrush’) is described from one of the first fully authenticated tape-recordings of this vocalisation, and is shown to be distinctly different from that of the race ruficollis (‘Red-throated Thrush’). Further studies of voice, mate selection, and breeding biology in general are needed for a full clarification of Dark-throated Thrush taxonomy. he Dark-throated Thrush Turdus rufi- ruficollis and atrogularis were found to be sepa- collis is considered by most recent rated by habitat, and no mixed pairs or hybrids Tauthors (e.g. Portenko 1981; Cramp were recorded (Stakheev 1979; Ernst 1992); in 1988; Glutz & Bauer 1988; Clement & Hathway Mongolia, hybridisation was reported to occur 2000) to be polytypic, comprising the red- in the northwest (Mongolian Altai and Great throated nominate race ruficollis and the black- Lakes Depression) by Fomin & Bold (1991), but throated atrogularis. The two races interbreed observations of passage ruficollis farther east in where they overlap in the east and southeast of the country showed very little evidence of the range (Clement & Hathway 2000), with hybridisation (Mauersberger 1980). Indeed, intermediates reported from the Altai, western nominate ruficollis and atrogularis were Sayan, and upper Lena and upper Nizhnyaya regarded by Stepanyan (1983, 1990) as separate Tunguska rivers (Dement’ev & Gladkov 1954). species, and this view was shared by others, The situation is by no means clear-cut, including Evans (1996) ‘based primarily on however: in, for example, the Altai (Russia), plumage and ecological differences’, but also © British Birds 96 • February 2003 • 79-83 79 Song of the Dark-throated Thrush Stephan Ernst 50. Male Dark-throated Thrush Turdus ruficollis atrogularis, near Aktash, Altai Mountains, Russia, July 1999. taking into account slight differences in song simple in structure and, like other Siberian and calls between the two, as apparently evident thrushes (e.g. Eyebrowed Thrush T. obscurus, in the BWP account (Cramp 1988). Svensson Siberian Thrush Zoothera sibirica) and Fieldfare (1996) urged a more cautious approach, T. pilaris, has a rather slow pace, somewhat pointing out that the song of atrogularis was rambling presentation, and brief pauses apparently unknown and that no recording between each group of notes. Most of the units appeared to exist. Moreover, he drew attention are composed of series of simple chattering to the fact that the recording of an alleged sounds (‘chip-chip-chip’, ‘chi-chi-chi-chi-chi’, vagrant atrogularis in Sweden (S. Palmér/ ‘chet-chet-chet’, etc.). Interspersed among these Swedish Radio, May 1977), published in Palmér series of chattering notes is the most striking & Boswall (1969-80) and used for analysis in feature of the song: rich, rather low-pitched and BWP, related to a record about which little was slightly husky warbling units recalling elements known, and had not been submitted to the from the song of Blackbird T. merula, consis- Swedish Rarities Committee. In fact, the tently given as a pair of disyllabic notes, each recorded song sounded like, and most probably with the second note stressed and the final note was, that of a Song Thrush T. philomelos higher-pitched, suggesting ‘cherr-voo cherr-vee’. (Svensson 1996; LS in litt. 1996). At Mirnoye, 10-15 atrogularis males were Both MGW and LS have attempted to ascer- studied each year during 1995-97: the Black- tain whether the song of atrogularis had, after all, bird-like warbling notes were a constant feature been recorded, or whether Russian colleagues in the song of the local population, being given could fill the gap, if indeed one existed. In April by all the males studied; the song of some males 2000, VYA reported to MGW (in litt.) that T. r. indeed consisted of repeated warbling sounds atrogularis had at last been tape-recorded, by O. with very little chattering in between (VYA). V. Bourski at the Yenisey Ecological Field Station The section of song shown in fig. 1 suggests (in Mirnoye, on the Middle Yenisey river, Central ‘chet chet chet chet chet chet chet cherr-voo Siberia) in the summer of 1997. It was not until cherr-vee tsirrr tsirrr’, the last two notes being a the autumn of 2000 that VYA, having captured squeaky twittering. Two further types of chat- the song of atrogularis on tape at the Yenisey tering units are illustrated in figs 2 & 3. Some Station in June of that year himself, was able to chattering sounds in the recorded song have a send a copy of his recording (the original of strained quality, and they often closely resemble which is held at the Veprintsev Phonotheca of the bird’s own alarm calls, though sonograms Animal Voices [Library of Wildlife Sounds] in reveal structural differences (no sonogram of Pushchino, Russia) to MGW. alarm calls is included here as that section of From this one recording of atrogularis,the the recording has excessive background song may be described as follows. It is fairly sounds). The chattering also suggests less fre- 80 British Birds 96 • February 2003 • 79-83 Song of the Dark-throated Thrush kHz 10 8 6 4 2 1 2 3 4 5 6 7 s Fig. 1. Song of a Dark-throated Thrush Turdus ruficollis atrogularis (recording by V.Yu. Arkhipov, Mirnoye, Central Siberia, June 2000). netic units of the alarm rattle of Blackbird or kHz that of Song Thrush, while loud, bold and crisp 10 units even suggest a fragment of Song Thrush song. Clearly, however, the song as a whole 8 bears no resemblance at all to that of Song Thrush (contra BWP). From earlier observations in Central Siberia, 6 the characteristically hoarse and low-pitched song was reported to comprise a single phrase 4 of 3-4 units, loud, long and descending at the start, then short, sharp and ascending: ‘teee... tyuyuu... teeu-eet’, with call notes given medita- 2 tively in longer pauses between the main war- bling parts of the song (Rogacheva et al. 1991; Rogacheva 1992; Clement & Hathway 2000; 1 s K. Mikhailov in litt. to P. Clement). In Pakistan, in early May, prior to departure from the win- Fig. 2. Chattering sounds in the song of a tering grounds, birds strung together ‘quich Dark-throated Thrush Turdus ruficollis atrogularis quich’ and ‘quoit-quoit’ with some whistling (recording by V.Yu. Arkhipov, Mirnoye, Central sounds in between; this was interpreted as Siberia, June 2000). perhaps subsong or incipient song by Roberts (1992), but we suggest that this was more or less full song. kHz Comparison of atrogularis, based on the pre- 10 ceding description, with a single recording by M. Schubert of song (27 phrases) of ruficollis 8 from Mongolia, analysed by J. Hall-Craggs and MGW in BWP, and by LS for this short paper, reveals marked differences between the races. 6 The song of nominate ruficollis lacks the ram- bling, chattering quality characteristic of 4 atrogularis, consisting rather of short, fluty, well-spaced phrases, which are often built up in similar fashion, commonly as ‘chooee-chooee... 2 chulee chill-veeta’, where the ‘chill’ note is high- pitched and stressed (fig. 4). Of 27 phrases, only 14 are full, the others comprising a single figure 1 s – usually the initial figure ‘chooee-chooee’. The song of nominate ruficollis was elsewhere Fig. 3. Chattering sounds in the song of a Dark- reported to be simple and generally less melo- throated Thrush Turdus ruficollis atrogularis dious than that of Song Thrush: rambling and (recording by V.Yu. Arkhipov, Mirnoye, cackling ‘chve-che-chve-che... chvya-chya- Central Siberia, June 2000). chvya-chvya...’ (Clement & Hathway 2000; see British Birds 96 • February 2003 • 79-83 81 Song of the Dark-throated Thrush Vadim Ryabitsev Vadim 51. Male Dark-throated Thrush Turdus ruficollis atrogularis at nest with young, Poluy River in north of Western Siberia, June 1996. also transcription in Clement 1999). This ren- the song of atrogularis does, however, indicate a dering suggests series of chattering sounds, but strong resemblance between the races. Never- no such sounds are evident in the song of rufi- theless, a lack of relevant recordings prevents us collis recorded by M. Schubert. attempting any further analysis of similarities A comparison of the calls of nominate rufi- and possible differences specifically in respect of collis, recorded by B. N. Veprintsev and V. V. calls of the two races. For descriptions of Leonovich in Tyva (Russia), in June 1975 certain calls of both, including sonograms of (Palmér & Boswall 1969-80; Veprintsev 1982- ruficollis calls, see Ernst (1992, 1996). 86; see fig. VI, and renderings, in BWP), with In conclusion, any taxonomic reassessment our description of calls and chattering units in of the Dark-throated Thrush T. ruficollis where Werner Suter Werner 52. Male Dark-throated Thrush Turdus r. ruficollis, north of Nizhneangarsk, Lake Baykal, Russia, June 1991. 82 British Birds 96 • February 2003 • 79-83 Song of the Dark-throated Thrush kHz 10 8 6 4 2 1234 s Fig. 4. Song of a Dark-throated Thrush Turdus r. ruficollis (recording by M. Schubert, Mongolia, June 1979) (Schubert 1982). the vocalisations are used will indeed need to be Mongolian People’s Republic]. Nauka, Moscow. (In Russian) based on an analysis of further recordings of Glutz von Blotzheim, U. N., & Bauer, K. M. (eds.) 1988. Handbuch der Vögel Mitteleuropas 11. AULA-Verlag, song and calls from different parts of the range. Wiesbaden. In addition, the vocalisations of intermediates Mauersberger, G. 1980. Ökofaunistische und biologische should be investigated.