Caluta 6 (September 2014) Caluta o. 6 September 2014 Contents Editor-in-chief Annika Forsten [email protected] Editor Antero Lindholm [email protected] Editor Roderick Dixon Editor Roy Hargreaves 1. Occurrence of the alternative call of Common Chiffchaff in Finland and Estonia ISSN 2342-0510 For more information: ANTERO LINDHOLM http://www.caluta.liitin.net/ © The authors Caluta 6 (September 2014) Occurrence of the alternative call of Common Chiffchaff in Finland and Estonia ANTERO LINDHOLM Chiffchaff calls The normal call of Chiffchaff is used both as a contact call between different individuals and as an The normal call of Common Chiffchaff alarm call (Cramp 1992). Typically it is used in is well-known to Phylloscopus collybita contact between the individuals of loose autumn birdwatchers in Europe. It is similar in the groups. It is also used as a distress call when birds nominate subspecies of Western Europe and are in the hand – this is different from most bird which breeds in Northern and Eastern abietinus species, which normally do not use similar calls in Europe (Cramp 1992). However, in the earlier the hand to those used in "normal" contact literature the call was stated to be somewhat situations (pers. obs.). There is much variation in different between the subspecies with abietinus this call, which may be dependent on the context in having a call resembling the modern concept of the which the call is used, but this is far from clear. tristis call (Ticehurst 1938), or only eastern having this like call, with western abietinus tristis – In some years, especially in autumn, there has been sounding like the nominate (Dean 1985). abietinus widespread occurrence in Western and Northern Later still, Clement (1998) describe the calls et al Europe of Chiffchaffs with a different call, unlike of eastern as somewhat different to those abietinus the normal call of Common Chiffchaff, but also of nominate and western by collybita abietinus unlike normal calls of any other known Chiffchaff having the tonal quality of : high-pitched and tristis taxon. Those calls have generated much discussion shrill and often slightly discordant 'peep', 'weep', and speculation and also some confusion. In 'pseet' or 'cheet'. Their sound spectrogram of an English, this call is referred to as the 'sweeoo' – call, recorded in Moscow, shows a call abietinus call, and this name has been used here (also spelled very like a normal call. I am not sure if collybita 'wheeoo' in some sources, and other variations the variation they report in calls is really abietinus have also been used). geographical – in any case I would not go as far as Jännes (2002) and equate their description of I consider the 'sweeoo' call to be a call with at least eastern to the 'sweeoo' call described and abietinus two parts: first ascending and then descending so discussed below in this article. The most distinct that the descending part reaches lower, or at least change in the calls occurs in the same area where almost as low, as the start of the ascending part ( the song changes – in the contact zone of cf tristis the definition of call types further in this text). The and just west of the Urals. In addition to abietinus published descriptions of calls are often unclear. calls, and also have very similar collybita abietinus Figure XII of Cramp (1992) resembles an songs. The call and song are different in the taxon "imperfect" type of 'sweeoo' call as referred to (normally treated as a subspecies) of the tristis here, but otherwise Cramp (1992) or Glutz & Ural Mountains and eastward and in of ibericus Bauer (1991) do not include sound spectrograms the Iberian Peninsula, which is nowadays normally of 'sweeoo' calls. It seems both handbooks briefly treated as a different species, Iberian Chiffchaff. refer to this call: in Glutz as a kind of juvenile call, The vocalisations of and will not be tristis ibericus in Cramp not explicitly as such. Bergmann discussed any further here. et al (2008) describe an impure 'sfie' or 'psi' from autumn as well as spring, and based on the 1 Caluta 6 (September 2014) Occurrence of the alternative call of Common Chiffchaff in spectrogram this is a kind of 'sweeoo' call, and is easier to find and study throughout the summer. Finland and Estonia not attributed specifically to young birds by them. Dean (1985) mentions that "a shrill sweeoo is also The subspecies involved both in Estonia and recorded for autumn Chiffchaffs", referring to this Finland is abietinus (e.g. Clement et al 1998) call. Constantine et al (2006) clearly regard although there has been some speculation 'sweeoo' as a juvenile call. Dean & Svensson (2005) concerning the increase of nominate Chiffchaff in describe a shriller and clipped 'sweeu' that is uttered the area (Hansson et al 2000, Lampila et al 2009). by collybita, particularly, if not exclusively, by first-autumn birds – this seems to be a description of 'sweeoo' calls as understood here. However, also Material and methods a possibly different call, somewhat resembling the This article is based on sound recordings of normal call of tristis or the distress call of a Chiffchaff calls, recorded from 1998 to 2013 in chicken, is described as the call of nominate and Southern Finland and Estonia, and field notes from abietinus Chiffchaffs juveniles (Glutz & Bauer the same period. At the same time and in the same 1991, Svensson et al 2009). These two descriptions area in Finland, Chiffchaffs were trapped, ringed are often not clearly separated, and seem to be two and studied in the hand, and almost every bird extreme variations of basically the same call (this studied by me was also photographed. Some seems evident from Glutz & Bauer 1991). trapped birds were also sound-recorded. My call recordings are from short field trips made especially to record any calls of Chiffchaffs, so there is no bias Chiffchaffs in Southern Finland and towards unusual types. The additional material by Estonia others may be somewhat biased to include Chiffchaff is a common breeder in both Finland and "interesting" material – especially 'sweeoo' calls. Estonia. On the south coast of Finland it is a somewhat scarce breeding bird and mostly confined The calls were recorded in many situations. As to dense forests with a component of spruce. It noted earlier, Chiffchaffs use calls that to the occurs in the suburban forests of the Helsinki area, human ear are very similar in many different but is uncommon, and now and then also breeds in contexts. There are variations in intensity and tone, deciduous forests with very little spruce (Solonen et which were not dealt with in this analysis. One call al 2010, pers. obs.). During the spring migration, per individual was used in the analysis. Often the mostly in early May, Chiffchaffs often fly over the call of an individual is somewhat variable, or at coast without stopping and are mostly seen on least there are some variant notes. One call per each smaller islands close to the coast, less on the recording was chosen and is meant to represent mainland, and in late summer they tend to disappear what is typical for the individual. in the forests and, therefore, they are not observed that often. During autumn migration, especially Initial and terminal pitches of the call notes were mid-September to early October, they occur measured, also the highest and lowest pitches, and commonly in many bushy areas, reed beds and the length of the call. The measurements were done urban parks of Helsinki and are, therefore, easiest to with the program Syrinx, version 2.6h, (c) John study at that time (Solonen et al 2010, pers. obs.). Burt 1995-2006, www.syrinxpc.com. The measurements were taken from recordings of In Northern Estonia, less than 100 km to the south, sampling frequency 22050 Hz. When measuring on the other side of the Gulf of Finland, Chiffchaff from the frequency axis, the spectrogram was is much more common as a breeding bird – one of plotted with FFT length 1024, and for the time axis, the commonest breeding passerines in forested FFT length 128 was used. areas (the sixth most numerous bird species countrywide, Elts et al 2009). That makes them 2 Caluta 6 (September 2014) Call variation One variation is a call with a strong second layer – almost as strong as the fundamental, but which is The sound spectrograms of the samples are not a true harmonic layer. The second layer may depicted in Figures 1-8. The corresponding start somewhat earlier than the fundamental, lies recordings can be heard on the Xeno-canto web not that high up as true harmonic layer should be, site, and the reference numbers can be found in the and may be of somewhat different shape. The captions of Figures 1-8. Addresses for the overall effect on the sound is similar to that of the recordings are of type http://www.xeno- true harmonic. Calls of this kind are common in canto.org/195749, which locates the recording spring and occur also in autumn. Figure 3 shows XC195749. such a call. Figure 4 shows a variation, where the upper sound starts distinctly earlier – by adding one Call notes were classified into five groups: T1 arm this would be quite close to the 'sweeoo' call. (more or less straight ascent), T2 (like T1, but at This may be only a co-incidence and the call does the end, a very short descending part), H1 (first an not sound like a 'sweeoo'. ascending part then descending, then ascending. The starts is higher than the end, but neither is the 'Sweeoo' calls are in fact quite distinct.