Crossbill call types in the western Palearctic – a birder’s perspective

Julien Rochefort & Ralph Martin

Ceci est la version anglaise de l’article. Cliquez ici pour lire la version française

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In this blog post we summarise some of the results on our ongoing research on crossbill (Loxia spp.) call types. The original results will be presented in a series of papers in peer-review journals and include the delimitation, spatial distribution and temporal variation of crossbill call types. The first of the original papers has recently been published:

Martin, R., Rochefort, J., Mundry, R., & Segelbacher, G. (2019). Delimitation of call types of Common Crossbill ( Loxia curvirostra ) in the Western Palearctic. Ecoscience 26 (2): 177-194

Access to this paper is limited to paying customers, but you can view a pdf-file of the accepted manuscript here for free. In this article, the methods of the analysis and the underlying mechanisms behind call type differentiation of crossbills are in focus. The aim of this blog post is to raise awareness on the topic to a wider public, to present a guide to identification and to encourage birders to record and delimitate crossbill call types. Additional results will be added to this blog post after further articles have been formally published.

A widespread assumption among birders is that identification of crossbill call types and crossbill species by calls is very difficult (‚technique and required knowledge is only available to a few‘ Shirihai & Svensson (2018)). With this article we want to change this and after reading and some practice you should be able to separate the call types and species.

Introduction

Crossbills are partly nomadic living finches (Perrins & Cramp 1998), which might occur everywhere, where conifers grow on the northern hemisphere. Their vocal repertoire comprises song (about 40 different themes for each call type; own data), flight calls (FCs), excitement calls (ECs), chitter calls, begging calls, alarm calls and some other unobtrusive vocalisations which are not very distinctive (see Figure 1).

Figure 1: Call spectrum of crossbills. From the left side above to the right side below: Flight calls: Call type N4 (background species: Goldcrest Regulus regulus), 20.9.2017, Germany © Ralph Martin; excitement calls: Call type N7, 08.10.2015, Germany © Ralph Martin; chitter calls: Call type N4, 06.12.2017, France © Julien Rochefort; begging calls: Call type N4, 18.09.2016, Great Britain © Ralph Martin; alarm call: Call type N7, 24.12.2012, France © Julien Rochefort. After the alarm call in the beginning the whole flock takes off at once.

FCs can be best described as contact calls and are – as the title suggests – the most common call used in flight. Nevertheless, they are also commonly used when perched. They often sound sharp, piercing and sometimes klicking. Amplitude is typically quite extensive. If present in your recordings, harmonics are few. Contrastingly, ECs are hardly used during flight but especially when the bird is perched and agitated. This happens, for example, if there is an ongoing disturbance or threat like a perched Pygmy Owl (Glaucidium passerinum), the excitement after an attack of a Sparrowhawk (Accipiter nisus) or a conflict with another crossbill pair. They are often uttered in quick series for several minutes. ECs are on average lower than FCs and less pure sounding. Typically, they show a high number of harmonics. The amplitude of ECs is usually more restricted than in ECs. Alarm calls are very similar to ECs but are more quiet and more variable. Typically, they are uttered once if there is an immediate threat and within fractions of a second, all crossbills take off. Chitter calls are often used while feeding in a tree. They are more variable than FCs and ECs but many call types can be separated by their chitter calls with some practice. However, we do not show them here, as they are less obvious. Begging calls are mostly used by fledglings but sometimes also by adult females begging the male for food during courtship. We are not aware of differences in begging calls between the call types. However, begging calls change with the age of the fledglings. Within several weeks, the fledglings start to practice FCs and ECs, that are less defined in structure in the beginning. Such calls can look little bit different compared to adult calls in a spectrogram, however, you will be able to recognize young birds, because variation within calls of a series is larger than in adult birds (see Figure 2). After few more weeks, young birds use FCs and ECs like adult birds.

Figure 2: Series of FCs and ECs of four different individuals of call type N7. The upper two lines show calls of adult birds, the lower two lines show calls of young birds. The calls are extracted from recordings of about one minute of length of each individual. While adult birds show stable calls (differences between calls mainly due to recording quality / bird turning the head), calls of young birds are instable for several weeks. In extremes, call type of such young birds can be hard to identify. 1st row: (background species: Red Crossbill call type N08 FCs and ECs, Coal Tit Periparus ater) 17th of October 2014, Germany © Ralph Martin; 2nd row: (background species: Red Crossbill call type N04 FCs) 30th of October 2013, France © Julien Rochefort; 3rd row: 4th of December 2013, France © Julien Rochefort; 4th row: 1st of November, 2011, Germany © Ralph Martin.

Several times we used now the term ‚call types‘ – so we would like to address the question what crossbill call types are. It was Brehm (1853) who first noticed that calls sometimes differ between crossbill individuals despite having no recording equipment at all. Later, there were further publications on the topic (like Weber 1972). The first detailed study on the subject was made by Groth (1988) and in more detail Groth (1993b) in North America. He wrote, that the Red Crossbill (Loxia curvirostra) can be split into discrete subpopulations, so called ‘call types’, which are separated especially by their distinct FCs and ECs. To a lesser extent they differ in their morphologic features and here, bill depth was described to differ strongest among call types (Groth 1993b). Each crossbill can be assigned to one of these call types. More or less pronounced genetic differences have been shown for some call types as well (Parchman et al., 2016).

Until recently, seven to nine call types have been described in central and northern Europe (Clouet & Joachim 1996, Robb 2000, Summers et al. 2002, Edelaar et al. 2004, Constantine & The Sound Approach 2006). With our mentioned article (Martin et al. 2019) and this one here, we describe at least 18 different call types of Red Crossbill and two call types of Parrot Crossbill (Loxia pytyopsittacus) for the Western Palearctic.

Starting to identify crossbill call types is easiest in late summer or autumn. Search a forest with abundant fresh cones of spruce or larch and you will find crossbills. Listen carefully to the calls, try to separate FCs and ECs, try to visualize how a spectrogram could look like and try to record them. Check the spectrograms at home and compare the result with your thoughts in the field. Do this again and again. You will be able to tell the FCs (and some ECs) of the common call types apart within a short time by ear. Nevertheless, from time to time there will be birds you will hardly be able to give them a name in the field. Especially in late winter and spring this will happen more commonly. The reason for this is an effect named ‚call matching‘ (Groth 1993a). When the crossbill pairs form, they adjust their calls. Every pair has then its ‚own calls‘ which enables them to recognize their mate (see Figure 3). They are still typical for the call type and many of these calls will hardly attract your attention in a spectrogram (but might sound unfamiliar in the field). Rarely, there are more ‚creative‘ pairs with extraordinary calls. We cannot say for sure but by analysing FCs and ECs, we think, most of these were just creative while only a small percentage belongs to ‚hybrid pairs‘ (means the mates belonged to different call types and adjusted the calls to each other).

Figure 3: FCs of two pairs and a further individual, all of call type N1. 11th of January 2011, France © Julien Rochefort. At this time of the year, most birds are paired and show pair-distinctive calls which can be quite inventive and sound strange. Above the calls, we wrote numbers to clarify, which call belongs to which pair member (1 or 2). The single bird has the number three.

Unfortunately, there are very few studies about this topic (for example Keenan & Benkman (2008)) and almost no studies which analysed FCs AND ECs (one of the very few is Summers et al. (2002)). So keep in mind: If you want to deal with the crossbill topic, always try to record FCs AND ECs of the same bird. You will be rewarded with much more information about the bird. It might be easier to identify most crossbills by their FCs (especially in the beginning), but often the ECs contain more information in difficult cases. Unfortunately, especially in the beginning, it is very difficult to record both calls of an individual, but there are some tricks to use:

  • If a bird is perched in front of you, uttering FCs, chances are very low that it will switch to ECs itself. But you can try to motivate it. Crossbills are curious birds, so start pishing – offer the bird all your repertoire of ‚SH‘ and ‚S‘ sounds for several minutes. Sometimes, the bird will look at you in a strange way and just leave (well, we can imagine what these birds are thinking…). Rarely, the bird will just stop calling. But quite often, it will approach you and utter ECs. Silent in the beginning, but if you keep pishing, it might suddenly utter a loud series of ECs for some time. If you have bad luck, several crossbills will approach and you do not know any longer, which bird utters which calls.
  • If you are walking through a forest, looking for crossbills and you hear ECs in the distance, there is one piece of advice to give: ‚RUN!‘. Approach the bird as fast as possible – because it will typically stop calling within a short period of time. As soon as you are close enough, start recording. The bird will very likely switch to FCs again within few minutes. Ralph lost mobile phones and car keys while running towards exciting crossbills somewhere in the nowhere of Scottish forests. However, he was rewarded with recordings of both calls of an individual…

BUT: Always ensure, that it is the same bird which utters both calls. Watch it with binoculars and keep in mind, that there might be another bird (or birds) in the tree, well hidden.

If you are still(!) interested in crossbills and you want to contribute to the knowledge about the distribution of the different call types, you can help us. We created an online sheet, where you may add your data about recorded call types. You can also upload a recording to http://www.xeno-canto.org and ask in the online sheet for help with the identification. But we have one request: if you add data, please do not only add data of the rare call types, but also of the common ones present.

 

Methods

For this article, we analysed more than 10,000 recordings from the Western Palearctic region from mid of the 2000s until 2019. We (Julien Rochefort and Ralph Martin) analysed these recordings and clustered the found calls into call types. A selection of these calls (see details in Martin et al. 2019) were also clustered by six further persons (Balduin Fischer, Johannes Honold, Steve Klasan, Paula Martin, Lukas Pelikan, and Daniela Züfle) – the reliability classifiers. As there is no clear definition of ‘call type’, we first had to define what we wanted to name a call type. This is the following:

    • Calls have to be explicit. To ensure, the differences between call types are obvious, we only named a group of calls a call type if calls were assigned to the same group by more than four of the classifiers.
  • It is known that calls can deviate in sick birds and in offspring of pairs of mixed call types (Groth, 1993a), but then, they are only used by a single bird or by members of a single family. To exclude such variation, we only defined a distinct group of calls as a ‘call type’ if calls were recorded from at least five birds with a distance of more than 10 km between the recordings.

Crossbill behaviour changes from north to south with populations being said to live nomadic in the north and more or less resident in southern Europe (Perrins & Cramp, 1998). The nomadic behaviour is linked with the erratic fructification of conifers, especially spruces (Picea spp.) and Larches (Larix spp.) (Glutz von Blotzheim & Bauer, 2001). These tree species are more or less reduced to an occurrence north of 44°N (see Figure 4). Therefore, we separated our analysis in a dataset north of 44°N and one south of 44°N and analysed, if there are differences in the delimitation of call types between the northern and southern datasets.

Figure 4: Map of the distribution of Spruces (Picea spp.) and Larches (Larix spp.) within the study area (including non-native distribution). Distribution of Picea abies and P. obovata following EUFORGEN (2009), distribution of L. sibirica following AgroAtlas (2008), overlap zone of P. obovata and P. abies following Andersson (2005) and distribution of P. orientalis following the American Conifer Society (2017). Map made with Natural Earth (2018).

Results and discussion

Within the Palearctic region, we found at least 17 distinct call types of crossbills north of 44°N, while calls were extremely variable in the Mediterranean (except on islands and isolated distribution sites) with only few distinct call types recognizable. In the Mediterranean, we often found several very different calls at a recording location with intermediate calls present as well, impeding a clustering into call types. Similarity of calls among individuals seemed to decrease with distance with no or hardly similar calls in other regions (the same result was found by Björklund et al. (2013)). Many of the calls in southern areas resembled northern call types but nevertheless showed differences. We interpreted these birds as leftovers of former influxes from the north which adapted their calls to the local ones. To conclude, we were not able to assign most populations in Iberia or the southern Balkan to distinct call types, as variation was too large.

Nomenclature

Until today, there were two different nomenclatures for crossbill call types in Europe: Robb (2000) named them with a letter (A until F plus X (Constantine et al. 2006)), while Summers et al. (2002) numbered the different FCs (0-4) and each EC was named with a letter (A-E). The name of a call type consisted of a combination of a number and a letter (1A and 4E for example). Both nomenclatures were more or less compatible with each other (e.g. call type E corresponded with 1A, call type C with 4E). Unfortunately, we had to introduce a new nomenclature for the call types for several reasons:

  • we found some call types, which are similar to the call types described by Robb (2000) and Summers et al. (2002). However, except for the calls of Two-barred Crossbill, we did not find any call type with identical FCs and ECs as described earlier (see table S9 till S11 in our article), although some calls were similar or very similar (call type B/N1, C/4E/N4, D/N7, X/N8). Therefore we struggled to assign our call types to the ones previously published. We have some ideas, what the reasons for these differences are (see the discussion in Martin et al. 2019), however, we will analyse this in more detail in a separate article.
  • we found no call types, in which FCs or ECs were identical to the correspondent call of another call type, although some are very similar. Therefore, we see no reason to separate the nomenclature of FCs and ECs as done by Summers et al. (2002) (nevertheless, this was a great system to get a first insight into crossbill call types).
  • we found much more call types, as previously published. However, we could not just expand the system introduced by Robb (2000), because, this was already done by Förschler & Kalko (2009). Unfortunately, Förschler & Kalko (2009) published no ECs for these birds and therefore we cannot reproduce, which calls correspond with the call types found in our study.
  • as the crossbill call types of North America are named with a single number, we did not want to introduce this as well to avoid confusion.

Our nomenclature begins with a ‚N‘ or an ‚S‘. N means, we found the call type north of 44°N, S means, we found it south of 44°N (some call types were found both, north and south, but in this case, we used ‚N‘). Afterwards, we clustered the calls into groups in both areas and gave each group a number. Some of these groups could be confirmed as a call type (see the definition of call type in the Methods) while others were not confirmed. As we show in this article only the ‚confirmed‘ call types, there is sometimes a gap in the numbers (especially in the southern area).

Introduction to the different call types

Now we introduce the different call types. If available, we show for each call type spectrograms of FCs and ECs of typical individuals. We colored one call for each, FCs and ECs. Birds have a different sound organ than humans, the syrinx, and are able to make two different sounds at the same time. If both parts of the syrinx form the same sound at the very moment, there is only a red colored line. If both parts of the syrinx utters different sounds at the same point of time, we coloured the lower element of the call red and the upper blue. If there are further black lines in the spectrogram at the very moment, these are harmonics or some kind of overlay effects (an attempt to explain the different bands in the ECs can be found in the supplementary material S 1). Harmonics occur at a multiple of the fundamental frequency. Thanks to superimposition/overlay effects, however, further bands may occur. This is easiest to see in the ECs, but occurs in the FCs as well.

You can listen to the examples by clicking on the blue subtitles and the key features for identification are given in the spectrograms. We also show the variation of calls of 20 different individuals of each call type (if available). However, this selection is not random. In fact, we tried to show most of the variation with these 20 calls – so variation is by far larger in these spectrograms than a recording of 20 individuals in a forest.

To see identical spectrograms on your computer like we show here, you need to convert your files to 44 kHz/16 bit files (most files will be already in this format). Open these files in Raven Lite 2.0 with the following settings used: use 350 for ‘Focus (Spectrogram Window Size)’. Select ‘View’ in the menu bar, then ‘Configure view axes’ and use 1.52 seconds / line, and 9,050 Hz / line). You can also use Audacity, however, you cannot standardise the size of the spectrogram as in Raven. So you need to enlarge and reduce the spectrogram to get the same scale as we show here. To adjust the spectrogram settings in Audacity, see the previous blogpost. Use the value of 256 as a window size and you will have almost the same spectrogram as we show here.

If you click on an image, you will see an enlarged version. To return, use the ‚back‘ button of your mouse, or if you do not have one, use the ‚backspace‘ key of your keyboard. Same works for the recordings, which are opened if you click on the blue legend under the spectrograms.

Now, let’s start: Here is an overview of the presented vocalization types:

Figure 5: Overview of the presented crossbill crossbill call types and species. For each call type, ECs are shown on the left and FCs on the right and ECs and FCs of three different individuals are shown (if available in decent quality). For credits of the recordings, see supplementary material S 2 or open the print version.

If you want to deal with crossbill calls in the future, you can download a print version of figure 5 here.

Call type index

Red Crossbill call type N1
Red Crossbill call type N2
Red Crossbill call type N3
Red Crossbill call type N4
Red Crossbill call type N5
Red Crossbill call type N6
Red Crossbill call type N7
Red Crossbill call type N8
Red Crossbill call type N9
Red Crossbill call type N10
Red Crossbill call type N11
Red Crossbill call type N12
Red Crossbill call type N13
Red Crossbill call type N14
Red Crossbill call type N15
Red Crossbill call type N17
Two-barred Crossbill N19
Scottish (Parrot?) Crossbill N20
Parrot Crossbill call type N21
Parrot Crossbill call type N22
Red Crossbill call type N23
Red Crossbill call type S2
potential Red Crossbill call type S3
potential Red Crossbill call type S6
potential Red Crossbill call type S17
potential Red Crossbill call type S19
potential Red Crossbill call type S22
potential Red Crossbill call type S23

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Red Crossbill call type N1

In Central Europe, this is a quite common call type. It is probably congruent with Type B as first published by Robb (2000).

Figure 6: Adult male and juvenile N1 in Pinus mugo mugo in the German Alps, June 2012

Figure 7: FCs of N1 (background species: Coal Tit (Periparus ater), Chaffinch (Fringilla coelebs)). Austria, March 2015 © Ralph Martin

Red Crossbill Type N01 - ECsFigure 8: ECs of N1. France, November 2014 © Julien Rochefort

Figure 9: Variation of FCs of N1 of 20 different individuals

Figure 10: Variation of ECs of N1 of 20 different individuals

Similar FCs: N7, N23, S2, S22

Similar ECs: especially N11 (see figure 60)), N23

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Red Crossbill call type N2

This call type is quite rare and due to some knowledge gaps about its distribution, we would appreciate to get more information about it, especially from eastern Europe. We found it mainly in central Europe with the northernmost record in northern Germany (also in Spain and Greece very similar calls). Very obvious ECs, which surprisingly sometimes resemble calling Eurasian Nuthatch (Sitta europaea) if very distant.

Figure 11: An adult male and female of N2 in Pinus mugo uncinata in the French Alps. October 2018

Figure 12: FCs of N2 (background species: Dunnock (Prunella modularis), Coal Tit (Periparus ater), Red Crossbill call type N11). France, October 2018 © Ralph Martin

Figure 13: ECs of N2 (background species: Black Redstart (Phoenicurus ochruros), Mistle Trush (Turdus viscivorus), Willow Tit (Poecile montanus), Coal Tit (Periparus ater), Crested Tit (Lophophanes cristatus)). France, October 2018 © Ralph Martin

Figure 14: Variation of FCs of N2 of 20 different individuals

Figure 15: Variation of ECs of N2 of 20 different individuals

Similar FCs: N1, N6

Similar ECs: N15

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Red Crossbill call type N3

This is a very common call type in the whole of the northern half of Europe – sometimes referred to as ‘Type Y’ on the Internet and also in Edelaar et al. (2004).

Figure 16: An adult female of N3 in the Black Forest, Germany, March 2019

Figure 17: FCs of N3 (background species: singing Red Crossbill). France, November 2014 © Julien Rochefort

Figure 18: ECs of N3 (background species: Robin (Erithacus rubecula), Eurasian Nuthatch (Sitta europaea), Western Bonelli’s Warbler (Phylloscopus bonelli), Goldcrest (Regulus regulus)). France, April 2017 © Julien Rochefort

Figure 19: Variation of FCs of N3 of 20 different individuals

Figure 20: Variation of ECs of N3 of 20 different individuals

Similar FCs: Parrot Crossbill N21 (see figure 100)

Similar ECs: N8 (see figure 46), N9

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Red Crossbill call type N4

This is probably the most common call type in the northern half of the Western Palearctic. It is probably identical with type C published in Robb (2000) and ‘4E’ published in Summers et al. (2002).

Figure 21: Adult female and male of N4 on Helgoland, Germany, October 2013

Figure 22: FCs of N4. Germany, July 2015 © Ralph Martin

Figure 23: ECs of N4 (background species: Great Tit (Parus major)). Germany, February 2014 © Ralph Martin

Figure 24: Variation of FCs of N4 of 20 different individuals

Figure 25: Variation of ECs of N4 of 20 different individuals

 

Similar FCs: N5, N11, N15

Similar ECs: N5, N13, N15

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Red Crossbill call type N5

This call type occurs everywhere in Europe, but nowhere common.

Figure 26: FCs of N5. Germany, February 2014 © Ralph Martin

Figure 27: ECs of N5 (background species: Cuckoo (Cuculus canorus), Green Woodpecker (Picus viridis), Wren (Troglodytes troglodytes), Robin (Erithacus rubecula), Chiffchaff (Phylloscopus collybita), Eurasian Blue Tit (Cyanistes caeruleus), Carrion Crow (Corvus corone), Red Crossbill begging calls). France, April 2017 © Julien Rochefort

Figure 28: Variation of FCs of N5 of 20 different individuals

Figure 29: Variation of ECs of N5 of 20 different individuals

Similar FCs: N4; Parrot Crossbill N21 can be a confusion risk in low quality recordings.

Similar ECs: very similar to N4, however more pronounced ‚S‘-shape and second band (see figure 23 and figure 27). Lower band shorter than in N5 (see table 1 below); N13, N15

Table 1: Length of lower line in 33 individuals of N4 and 26 individuals of N5.

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Red Crossbill call type N6

This call type is mainly found in north-western Europe.

Figure 30: Male of N6 in Scotland, December 2014

Figure 31: FCs of N6 (background species: Coal Tit (Periparus ater), Chaffinch (Fringilla coelebs), Bullfinch (Pyrrhula pyrrhula), Red Crossbill N4 EC, ECs of N6, begging calls). Great Britain, December 2014 © Ralph Martin

Figure 32: ECs of N6. Great Britain (background species: FCs of Red Crossbill N6), December 2014 © Ralph Martin

Figure 33: Variation of FCs of N6 of 20 different individuals

Figure 34: Variation of ECs of N6 of 20 different individuals

 

Similar FCs: N2, N23

FCs sometimes very similar to N2 and some might be inseparable. However, until today, we did not find them in overlapping areas. N6 is more or less restricted to Great Britain and adjacent coasts, while N2 was found in southern Europe from Germany to Slovakia down to Iberia and the Balkans.

Similar ECs: N23

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Red Crossbill call type N7

This is a quite common call type in central Europe. It is probably identical with Type D published in Robb (2000)

Figure 35: Adult male of N7 in the Black Forest, Germany, January 2017

Figure 36: FCs of N7 (background species: Marsh Tit (Poecile palustris)). Germany, November 2013 © Ralph Martin

Figure 37: ECs of N7 (background species: Great Tit (Parus major), Marsh Tit (Poecile palustris), Carrino Crow (Corvus corone), Red Crossbill call type N7 FCs). Germany, November 2013 © Ralph Martin

Figure 38: Variation of FCs of N7 of 20 different individuals

Figure 39: Variation of ECs of N7 of 20 different individuals

Similar FCs: N1 (see figure 36 for differences in the spectrogram and figure 40 (below) for differences in wavogram), N10, N23, S2, S22

Figure 40: Differences in the location of the amplitude between FCs of call type N1 and N7. Looking at the amplitude dependent of time, the largest (red) or second largest  amplitude (orange) is in N1 before the point of time with the maximum frequency (pink). In N7, both are typically after the highest frequency. For differences in spectrogram, see lower part of each line or figure 7 and figure 36.

Similar ECs: N10

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Red Crossbill call type N8

This is one of the most common call types of the northern half of Europe. This call type is probably identical with Type X which was published in Constantine & The Sound Approach (2006).

Figure 41: Group of N8 at a drinking site in southern Germany, November 2015

Figure 42: FCs of N8. France, December 2013 © Julien Rochefort

Figure 43: ECs of N8 (background species: singing Red Crossbill call type N8). France, December 2013 © Julien Rochefort

Figure 44: Variation of FCs of N8 of 20 different individuals

Figure 45: Variation of ECs of N8 of 20 different individuals

Similar FCs: N13, Scottish (Parrot?) Crossbill N20

Similar ECs: N3 (see Figure 46)

Figure 46: Differences between ECs of N3 and N8. France, January 2011 © Julien Rochefort

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Red Crossbill call type N9

This is a very rare call type in the Western Palearctic, with records beeing scattered over the whole northern half.

Figure 47: FCs of N9 (background species: Coal Tit (Periparus ater)). Germany, December 2016 © Ralph Martin

Figure 48: ECs of N9 (background species: Great Tit (Parus major), Chaffinch (Fringilla coelebs), Siskin (Spinus spinus), Red Crossbill call type N4 FCs). France, March 2011 © Julien Rochefort

Figure 49: Variation of FCs of N9 of 20 different individuals

Figure 50: Variation of ECs of N9 of 10 different individuals

Similar FCs: no real confusion risk, maybe N12

Similar ECs: N3, rarely N7

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Red Crossbill call type N10

A call type, which is almost restricted to some areas in southern France.

Figure 51: FCs of N10 (background species: White Wagtail (Motacilla alba), Western Bonelli’s Warbler (Phylloscopus bonellii)). France, August 2017 © Julien Rochefort

Figure 52: ECs of N10 (background species: Great Spotted Woodpecker (Dendrocopus major), Crested Tit (Lophophanes cristatus), Coal Tit (Periparus ater)). France, January 2013 © Julien Rochefort

Figure 53: Variation of FCs of N10 of 20 different individuals

Figure 54: Variation of ECs of N10 of 20 different individuals

Similar FCs: N7, S17

Similar ECs: N7, N14, N17

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Red Crossbill call type N11

This is a very common call type in central Europe. There are no records in our database from the northernmost parts however.

Figure 55: Three Crossbills of N11, licking minerals at a wall, December 2015

Figure 56: FCs of N11 (background species: Water Pipit (Anthus spinoletta), Black Redstart (Phoenicurus ochruros), Willow Tit (Poecile montanus)). Germany, October 2018 © Ralph Martin

Figure 57: ECs of N11. France, November 2014 © Julien Rochefort

Figure 58: Variation of FCs of N11 of 20 different individuals

Figure 59: Variation of ECs of N11 of 20 different individuals

Similar FCs: N4, N14

Similar ECs: especially N1 (see figure 60), N7

Figure 60: ECs of N1 and N11 of two juxtaposed individuals. Juxtaposition artificially created.

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Red Crossbill call type N12

Most times, this call type is restricted to south-western Europe, but records up to Switzerland. It is identical with call published by Clouet (2000).

Figure 61: Adult male N12 in the Spanish Pyrenees, January 2015

Figure 62: FCs of N12 (background species: Coal Tit (Periparus ater)). Spain, January 2015 © Ralph Martin

Figure 63: ECs of N12. Spain, January 2015 © Ralph Martin

Figure 64: Variation of FCs of N12 of 20 different individuals

Figure 65: Variation of ECs of N12 of 20 different individuals

Similar FCs: maybe N9 or N14

Similar ECs: N10, N14, N17, S2, S22

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Red Crossbill call type N13

This is a very rare call type. We would appreciate to get a note about any record to fill knowledge gaps about its temporal and spatial distribution.

Figure 66: FCs of N13 (in background: Long-tailed Tit (Aegithalos caudatus), Marsh Tit (Poecile palustris)). Germany, January 2014 © Peter Schleef

Figure 67: ECs of N13 (in background: Blackbird (Turdus merula), Short-toed Treecreeper (Certhia brachydactyla), Red Crossbill Type N4 FCs)). France, July 2013 © Julien Rochefort

Figure 68: Variation of FCs of N13 of 20 different individuals

Figure 69: Variation of ECs of N13 of five different individuals

Similar FCs: N8, Scottish (Parrot?) Crossbill N20

Similar ECs: N4, N5, N15

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Red Crossbill call type N14

This call type is restricted to a small area in the southern Alps.

Figure 70: Adult male of N14 in the Italian Alps, October 2018

Figure 71: FCs of N14 (in background: Robin (Erithacus rubecula), Coal Tit (Periparus ater), Nutcracker (Nucifraga caryocatactes)). Italy, October 2018 © Ralph Martin

Figure 72: ECs of N14 (in background: Alpine Marmot (Marmota marmota), Coal Tit (Periparus ater), Eurasian Treecreeper (Certhia familiaris), Chaffinch (Fringilla coelebs)). France, July 2011 © Julien Rochefort

Figure 73: Variation of FCs of N14 of 20 different individuals

Figure 74: Variation of ECs of N14 of 20 different individuals

Similar FCs: N4, N11, N12

Similar ECs: N10, N12, N17

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Red Crossbill call type N15

This is a very rare call type with just a handful of records, which are all from north-western Europe.

Figure 75: FCs of N15 (in background: Robin (Erithacus rubecula), Great Tit (Parus major), Brambling (Fringilla montifringilla)). France, December 2015 © Julien Rochefort

Figure 76: ECs of N15 (in background: Goldcrest (Regulus regulus)). France, December 2012 © Bertrand Dallet

Figure 77: Variation of FCs of N15 of 13 different individuals

Figure 78: Variation of ECs of N15 of five different individuals

Similar FCs: N4 (see figure 75 for differences in spectrogram and figure 79 for differences in wavogram)

Figure 79: Differences between FCs of call type N4 and N15. In spectrogram, the main difference is the location of the lowest part of the call. Looking at the wavogram (amplitude dependent of time), amplitude is larger in the first decreasing part of the spectrogram of the call (red line) in N15 than in N4. Amplitude is especially smaller in N4 than in N15 at the second minimum of the call (pink line; lowest minimum of the call in N4, but the second lowest minimum in N15).

Similar ECs: Scottish (Parrot?) Crossbill N20 (see figure 76 for differences), N2, N5, N13
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Red Crossbill call type N17

This call type is restricted to an extremely small area in the Alps. Extraordinary and highly unusual FCs.

Figure 80: A male of N17 in the French Alps, October 2018

Figure 81: FCs of N17 (in background: Coal Tit (Periparus ater), Robin (Erithacus rubecula)). France, August 2017 © Julien Rochefort

Figure 82: ECs of N17 (in background: Coal Tit (Periparus ater)). France, October 2018 © Julien Rochefort

Figure 83: Variation of FCs of N17 of 20 different individuals

Figure 84: Variation of ECs of N17 of 20 different individuals

Similar FCs: S23

Similar ECs: N10, N12, N14, N17

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Two-barred Crossbill N19

Two barred Crossbill (Loxia leucoptera bifasciata) occurs mainly in Scandinavia and Siberia with rare records apart from there. Calls published already by different sources like Roché (1993), Robb (2000), Constantine & The Sound Approach (2006) & Bergmann et al. (2008). No differences found between the calls within the Palearctic region.

Figure 85: Two-barred Crossbill (N19). Germany, October 2013

Figure 86: FCs of Two-barred Crossbill (N19) (in background: Red Crossbill Type N4). Sweden, August 2011 © Patrik Åberg

Figure 87: ECs of Two-barred Crossbill (N19) (in background: Marsh Tit (Poecile palustris)). Germany, November 2013 © Ralph Martin

Figure 88: Variation of FCs of N19 of 20 different individuals

Figure 89: Variation of ECs of N19 of 20 different individuals

Similar FCs: N7 sounds similar

Similar ECs: only trumpeting Northern Bullfinch (Pyrrhula pyrrhula pyrrhula) is a confusion risk. However, calls lack the descending ending of the call.

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Scottish (Parrot?) Crossbill N20

This population is restricted to Scotland with few records elsewhere. This is Scottish (Loxia scotica) or Scottish Parrot Crossbill (Loxia pytyopsittacus)(see Summers et al. 2002). An update of this article, detailing the problem of the identity of these crossbills, will follow.

Figure 90: Young male of a Scottish (Parrot?) Crossbill. Scotland, August 2017

Figure 91: FCs of Scottish (Parrot?) Crossbill (N20) (in background: Chaffinch (Fringilla coelebs)). Great Britain, September 2016 © Ralph Martin

Figure 92: ECs of Scottish (Parrot?) Crossbill (N20) (in background: Coal Tit (Periparus ater)). Great Britain, December 2014 © Ralph Martin

Figure 93: Variation of FCs of N20 of 20 different individuals

Figure 94: Variation of ECs of N20 of 20 different individuals

Similar FCs: N8, N13

Similar ECs: N15 (see figure 76 for differences), N21, N2
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Parrot Crossbill call type N21

This call type of Parrot Crossbill was found throughout the breeding area of Parrot Crossbill. Visual identification of the birds was congruent with aural identification in 89 cases with no birds identified as Red Crossbill by sight. Also confirmed by two ringed and sound-recorded birds (Buckx, 2017).

Figure 95: Young male of Parrot Crossbill N21, Germany, October 2013

Figure 96: FCs of Parrot Crossbill N21 (in background: Great Spotted Woodpecker (Dendrocopus major), Great Tit (Parus major)). Sweden, March 2013 © Jelmer Poelstra

Figure 97: ECs of Parrot Crossbill N21 (in background: Willow Tit (Poecile montanus), Chaffinch (Fringilla coelebs)). Sweden, April 2012 © Jelmer Poelstra

Figure 98: Variation of FCs of N21 of 20 different individuals

Figure 99: Variation of ECs of N21 of 20 different individuals

Similar FCs: N3 (see Figure 100), recordings of distant birds can look similar to N5 (see figure 100)


Figure 100: Comparision of FCs of Parrot Crossbill N21, Red Crossbill call type N3 and Red Crossbill call type N5.

Similar ECs: Scottish (Parrot?) Crossbill N20, maybe Parrot Crossbill N22?

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Parrot Crossbill call type N22

A call type that was connected with visual identifications of Parrot Crossbills several times and by several observers. It was mainly found in eastern Scandinavia. However, until today we have not received a recording that doubtlessly shows the ECs. So we would be happy about a note in case you are able to record these calls but also more data about its distribution is desirable.

Figure 101: FCs of Parrot Crossbill N22 (in background: Common Crane (Grus grus), Chaffinch (Fringilla coelebs), Red Crossbill FCs of Type N3 and N4). Finland, June 2013 © Antero Lindholm

Figure 102: Variation of FCs of N22 of 20 different individuals

Similar FCs: none very similar, maybe N3 and N21

Similar ECs: ?

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Red Crossbill call type N23

A call type which was only found in the Benelux-area. At the moment, we are not completely sure about the specific status of it (we will discuss this one day in more detail). So we would appreciate any information about recorded birds.

Figure 103: FCs of N23 (in background: Redwing (Turdus iliacus)). Netherlands, October 2013 © Herman van Oosten

Figure 104: ECs of N23. Netherlands, October 2013 © Herman van Oosten

Figure 105: Variation of FCs of N23 of nine different individuals

Similar FCs: N1, N7, S2, S22

Similar ECs: ? hardly known. N1 and N11 look similar.

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Red Crossbill call type S2

This call type is restricted to Corsica Island and therefore likely represents ssp. corsicana. Only few recordings of ECs available.

Figure 106: FCs of S2 (in background: Coal TIt (Periparus ater)). Corsica, September 2014 © Johannes Honold

Figure 107: ECs of S2 (in background: Coal Tit (Periparus ater), Red Crossbill Type N1, and the S2 bird is also singing quietly and uttering FCs). Corsica, September 2014 © Stefan Werner

Figure 108: Variation of FCs of S2 of 20 different individuals

Similar FCs: N1, N7, N23, S22

Similar ECs: N12, N14, N17, S22

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Further potential call types:

There are much more call variations in the Mediterranean, however, most do not seem to be a distinct call type. Here, we show calls of further populations, which might fit to the definition of call types, thanks to their isolated distribution or a quite northerly distribution within the range of erratic seed producers. For some of them, we did not have enough recordings to conclude finally about their status and also their identification.

Be careful when identifying a southerly population outside its regular distribution range. As variation seems to be larger in general and there are areas with very variable calls in southern Europe, it is almost impossible to identify a bird for sure just by its FCs. Sometimes, identification might be possible by the combination of FCs and ECs, but we need more knowledge about these populations to decide.

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Red Crossbill call type S3

The Cyprus crossbills might be quite distinctive thanks to their isolated occurrence. Although we found very variable calls, sometimes strongly resembling northern calls (suggesting regular influxes from northern populations) the following calls appeared more often and we could not find these calls anywhere else. Therefore, they might be connected to the ‘original Cyprus Crossbill’.

Figure 109: FCs of S3. Cyprus, August 2013 © Matthias Feuersenger

Figure 110: ECs of S3. Calls are not known well enough to give features (in background: Coal Tit (Periparus ater), Short-toed Treecreeper (Certhia brachydactyla)). Cyprus, August 2013 © Matthias Feuersenger

Similar FCs: probably none extremely similar. Maybe sometimes N2 and Parrot Crossbill N22. Rarely N10.

Similar ECs: ECs not known well enough

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Red Crossbill call type S6

Moroccan crossbills might be quite distinct thanks to their isolated distribution (see also Parchman et al. 2018). However, right now we only have recordings from few sites and variation is quite large. So we are looking forward getting our hands on further recordings.

Figure 111: Male of Red Crossbill S6, Morocco, March 2014

Figure 112: FCs of S6. Morocco, March 2014 © Ralph Martin

Figure 113: ECs of S6 (in background: Cuckoo (Cuculus canorus), Maghreb Chaffinch (Fringilla coelebs spodiogenys). Morocco, March 2014 © Ralph Martin

Similar FCs: variation is large and not sufficiently known. S22 is similar.

Similar ECs: No similar ECs for the shown example, but variation is large and not sufficiently known.

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Red Crossbill call type S17

A call type which could not be confirmed in Martin et al. (2019), because we did not enough recordings available and none that show FCs and ECs of the same bird. Nevertheless, we are quite confident, these birds will fulfil the set conditions of a call type. This is why we would be grateful for additional material. The birds were found especially in the Caucasus and adjacent regions so far.

We have only some low quality recordings of ECs from birds which likely belong to this population. These recordings are shown below.

Figure 114: FCs of S17. Georgia, September 2014 © Krzysztof Deoniziak

Figure 115: Variation of FCs of S17 of 20 different individuals

Figure 116: Variation of probable ECs of S17 of six different individuals

Similar FCs: resembles sometimes N10.

Similar ECs: if the shown ECs belong to this call type, they resemble especially N11 (and maybe N1). However, we do not know enough examples of these ECs.
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Red Crossbill call type S19

We know these calls only from the southern half of the Balkan Peninsula (first recorded by Bert Jahnke, Steve Klasan and Lukas Pelikan). We do not have recordings of any excitement calls, nor do we have a sufficient number of recordings to decide if this is a distinct call type for sure.

Figure 117: FCs of S19. Bulgaria, June 2014 © Bert Jahnke

Figure 118: Variation of FCs of S19 of three different individuals

Similar FCs: Resembles a bit of N15 and Two-barred Crossbill N19.

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Red Crossbill call type S22

Endemic to the Balearic Islands (we have only recordings from Mallorca but it might occur on Menorca as well) and therefore probably quite distinct (see Parchman et. al. 2018). This population likely fulfils the conditions set for a call type. Unfortunately, we have just few low quality recordings from the last years and only some older ones in good quality, which we show here.

Figure 119: FCs of S22. Mallorca, September 2007 © Pim Edelaar

Figure 120: ECs of S22. Mallorca, September 2007 © Pim Edelaar

Similar FCs: N1, N7, N23, S2 and S6. On the Spanish mainland, there are birds with very similar FCs.

Similar ECs: N12, N14, N17, S2

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Red Crossbill call type S23

We are not sure right now, if this is a genuine call type or if it is related to an already known call type (N17).  Nor do we know for sure how the ECs look like. These crossbills seem to occur especially in the south-western Balkans.

Figure 121: FCs of S23 (in background: Wood Warbler (Phylloscopus sibilatrix), Goldcrest (Regulus regulus)). Montenegro, September 2014 © Ralph Martin

Figure 122: Variation of FCs of S23 of five different individuals

Similar FCs: Very similar to N17. No details can be given before further recordings will be analysed.

Similar ECs: ?

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Because of the isolated location, there might be a distinct population on Sicily around the Etna (regular occurrence of crossbills). However, we could not get our hands on a single recording of these birds.

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Note

If you come across an error, a broken link, a misspelled name, a wrongly linked recording or something similar in this blog post, please let us know! numbers for you: Our dataset currently contains 16,000 sound recordings of 680 sound recordists. These recordings contain calls and songs of more than 50.000 crossbills (not necessarily different individuals). Included are recordings from Iceland to Japan, from Norway to Morocco, from remote regions of China and the Siberian forests. And it contains sound recordings from 1960 till today. All this would have been impossible without your help._

Acknowledgements

Our dataset of crossbills currently contains 16,000 sound recordings of 680 sound recordists. These recordings contain calls and songs of more than 50.000 crossbills (not necessarily different individuals). Included are recordings from Iceland to Japan, from Norway to Morocco, from remote regions of China and the Siberian forests. And it contains sound recordings from 1960 untill today. It is surely one of the biggest projects ever done of its kind. All this would have been impossible without your help! So we wish to thank for all the support we encountered from you, for recording crossbills and giving acess to these recordings. We also want to thank the operators of waarneming.nl, waarnemingen.be, observation.org, xeno-canto.org and the different ornitho-platforms for these really extraordinary data sets! We want to thank Arnoud van den Berg, Thijs Fijen, Balduin Fischer, Johannes Honold, Steve Klasan, David Jardine, Lukas Pelikan, Michèle Péron, Magnus Robb and Ron Summers for discussions and motivation during the project. We especially thank Thijs Fijen, Balduin Fischer, Johannes Honold and Lukas Pelikan for commenting on the manuscript of this blogpost.

Here is a list of the people who provided recordings – again, thank you very much again!

Aat Schaftenaar (7), Ad Postma (2), Adolf Goebel (1), Adri Clements (1), Aidan Place (4), Alain Fossé (1), Alan Burbidge (12), Alan Dalton (3), Alan Knox (419), Albert J. de Jong (3), Albert Lastukhin (37), Alex Thomas (2), Alexander Devos (1), Alexander Haralambiev (1), Alexander Lees (1), Alexander Neu (1), Alwin van Lubeck (2), Andre-Willem Faber (2), André Strootman (2), André van Reenen (3), Andreas Schaad (1), Andreas Stern (1), Andrzej Kosmicki (2), Andy Benson (1), Animation Nature (1), Annabel Runnel (1), Annette Hamann (1), Anon Torimi (8), Anonym (1), Ante Strand (5), Antero Lindholm (356), Antoni Knychala (2), Arend Wassink (2), Ari Ahtiainen (1), Arian Overweg (4), Arno Niehof (1), Arnold Berghorst (1), Arnoud van den Berg (41), Åse Haugen (3), Ashley Banwell (2), Balduin Fischer (19), Barbara Froehlich-Schmitt (3), Bart Gras (7), Bart Hoekstra (11), Bart ter Beek (2), Bas Klavr (1), Bas Kok (2), Bas van de Meulengraaf (6), Bas Verhoeven (1), Beatrix Saadi-Varchmin (8), beautykingfisher (5), Ben Ahmed (1), Benjamin Drillat (50), Benjamin Gnep (2), Benjamin Muis (1), Benjamin Simmelink (1), Benjamin Steffen (5), Benno van den Hoek (1), Benoit Nabhold (2), Bernard Bousquet (3), Bert Haamberg (8), Bert Jahnke (3), Bertrand Dallet (11), Birds In Flight (15), Birds of Pool Harbour (1), Bjorn Alards (3), Bodo Sonnenburg (3), Bram Koese (1), Bram Piot (12), Bram Rijksen (3), Bram ter Keurs (9), Bram Vogels (11), Brian Power (1), Bricke Gickel (4), Bruno Keist (41), C. Hazevoet (1), Carel van der Zanden (1), Carlos Fabregat (4), Caspar Groenewegen (1), Casper Zuyderduyn (3), Cedric Mroczko (23), Cees Struijk (3), Chris Batty (6), Chris Spijkerboer (1), Christian Brinkman (2), Christian Rixen (3), Christian Teule (2), Christoph Klein (4), Christophe Reijman (1), Christopher R. 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Supplementary material:


S 1: Attempt to explain the different bands found above the fundamental frequency in the ECs of crossbills:

Return to the introduction to the call types

_

S 2: Recording data to figure 5: N1, ECs, 1: Miesbach, Germany, 30.01.2014, J. Honold; 2: Kleines Walsertal, Austria, 21.08.2014, R. Martin; 3: Ravensburg, Germany, 27.12.2015, R. Martin; FCs, 1: Kleines Walsertal, Austria, 10.06.2014, J. Honold; 2: Ravensburg, Germany, 27.12.2015, R. Martin; 3: Ravensburg, Germany, 28.12.2015, R. Martin; N2, ECs, 1: Forêt domaniale de Saint-Prix Centre, France, 19.11.2014, J. Rochefort, 2: Finiels, France, 29.08.2015, J. Rochefort, 3: Finiels, France, 29.08.2015, J. Rochefort; FCs, 1: Haut-Folin, France, 21.11.2014, J. Rochefort; 2: Klingenbrunn, Germany, 07.02.2015, M. Péron; 3: Finiels, France, 28.08.2015, J. Rochefort; N3, ECs, 1: Morvan Mountains, France, 19.11.2014, J. Rochefort; 2: Rastatt, Germany, 29.11.2014, R. Martin; 3: Tiveden National Park, Sweden, P. Åberg; N3, FCs, 1: Yvelines, France, 13.6.2015, J. Rochefort; 2: Mölltorp, Sweden, 28.02.2016, P. Åberg; 3: Dänkritz, Germany, 09.03.2016, R. Martin; N4, FCs, 1: Rambouillet, France, 20.08.2013, J. Rochefort; 2: Mlawa, Poland, 06.01.2014, J. Matusiak; 3: Klingenbrunn, Germany, 01.02.2015, M. Péron; FCs, 1: Kattila, Finland, 31.03.2013, A. Lindholm; 2: Senart, France, 17.02.2014, J. Rochefort; 3: Rastatt, Germany, 25.11.2014, R. Martin; N5, ECs, 1: Fontainebleau, France, 28.02.2013, J. Rochefort; 2: Rambouillet, France, 17.04.2014, J. Rochefort; 3: Bad Segeberg, Germany, 20.01.2015, P. Schleef; FCs, 1: Fontainebleau, France, 04.03.2013, J. Rochefort; 2: St. Peter-Ording, Germany, 22.10.2013, P. Schleef; 3: Konstanz, Germany, 09.02.2014, R. Martin; N6, ECs, 1: Harwood Northumberland, Great Britain, 01.02.2012, S. Elliot; 2: Rambouillet, France, 13.11.2012, J. Rochefort; 3: Aviemore, Great Britain, 07.12.2014, R. Martin; FCs, 1: Rambouillet, France, 21.09.2012, J. Rochefort; 2: Rambouillet, France, 21.09.2012, J. Rochefort; 3: Abernethie, Great Britain, 08.12.2014, R. Martin; N7, ECs, 1: Karlsbad, Germany, 14.02.2014, R. Martin; 2: Calw, Germany, 17.10.2014, R. Martin, 3: Biberach, Germany, 05.11.2015, R. Martin; FCs, 1: Schaffhausen, Switzerland, 25.02.2015, R. Martin; 2: Schaffhausen, Switzerland, 25.02.2015, R. Martin; 3: Ravensburg, Germany, 27.12.2015, R. Martin; N8, ECs, 1: Biberach, Germany, 29.12.2015, R. Martin; 2: Dänkritz, Germany, 09.03.2016, R. Martin, 3: Landébia, France, 17.04.2016, J. Rochefort; FCs, 1: Rambouillet, France, 18.05.2014, J. Rochefort; 2: Winterthur, Switzerland, 27.06.2014, B. Keist; 3: Bavarian Forest, Germany, 21.07.2015, R. Martin; N9, ECs, 1: Fontainebleau, France, 11.03.2011, J. Rochefort; 2: Fontainebleau, France, 11.03.2011, J. Rochefort; 3: Plöttwitz, Germany, 17.03.2016, R. Martin; FCs, 1: Fontainebleau, France, 01.04.2011, J. Rochefort; 2: Werdau, Germany, 06.01.2016, R.Martin; 3: Plöttwitz, Germany, 17.03.2016, R. Martin; N10, ECs, 1: Morvan Mountains, France, 21.08.2012, B. Dallet; 2: Morvan Mountains, France, 02.12.2013, J. Rochefort; 3: Massif Central, France, 30.08.2014, J. Rochefort; FCs, 1: Forez, France, 30.08.2014, J. Rochefort; 2: Morvan Mountains, France, 21.11.2014, J. Rochefort; 3: Forez, France, 19.01.2016, J. Rochefort; N11, ECs, 1: Tatra, Slovakia, 06.05.2014, R. Martin: 2: Massif central, France, 01.09.2014, J. Rochefort: 3: Finsterau, Germany, 08.11.2014, M. Péron; FCs, 1: Klingenbrunn, Germany, 07.02.2015, M. Péron; 2: Jura, France, 11.03.2015, J. Rochefort; 3: Oberstdorf, Germany, 23.03.2015, R. Martin;  N12, ECs, 1: Gavarnie, France, 08.08.2014, J. Rochefort; 2: Finiels, France, 31.08.2015, J. Rochefort; 3: Finiels, France, 31.08.2015, J. Rochefort; FCs, 1: Gavarnie, France, 08.08.2014, J. Rochefort; 2: Finiels, France, 28.08.2015, J. Rochefort; 3: Finiels, France, 31.08.2015, J. Rochefort; N13, ECs, 1: Rambouillet, France, 31.07.2013, J. Rochefort; 2: Bad Segeberg, Germany, 17.02.2014, P. Schleef; 3: Morvan Mountains, France, 20.11.2014, J. Rochefort; FCs, 1: Rambouillet, France, 31.07.2013, J. Rochefort; 2: St. Peter-Ording, Germany, 25.08.2013, P. Schleef; 3: Gelderland, Netherlands, 15.09.2013, J. Veeken; N14, ECs, 1: Queyras, France, 31.07.2011, J. Rochefort; 2: Queyras, France, 06.08.2011, J. Rochefort; 3: Savoie, France, 22.08.2012, J. Rochefort; FCs, 1: Queyras, France, 31.07.2011, J. Rochefort; 2: Queyras, France, 06.08.2011, J. Rochefort; 3: Saint-Paul-sur-Ubaye, France, 11.07.2015, J. Rochefort; N15, FCs, 1: Rambouillet, France, 06.11.2012, J. Rochefort; 2: Rambouillet, France, 06.11.2012, J. Rochefort; 3: Fontainebleau, France, 04.03.2013, J. Rochefort; FCs, 1: Rambouillet, France, 30.09.2012, J. Rochefort; 2: Fontainebleau, France, 04.03.2013, J. Rochefort; 3: Saint-Cadou, France, 09.12.2015, J. Rochefort; N17, ECs, 1: Forêt du Seuil, France, 07.08.2015, J. Rochefort; 2: Forêt du Seuil, France, 07.08.2015, J. Rochefort; 3: Saint-Pierre-de-Chartreuse, France, 26.09.2015, B. Drillat; FCs, 1: Forêt du Seuil, France, 07.08.2015, J. Rochefort; 2: Crolles, France, 08.08.2015, B. Drillat; 3: Saint-Pierre-de-Chartreuse, France,  26.09.2015, B. Drillat; N19, ECs, 1: Västergötland, Sweden, 27.08.2011, P. Åberg; 2: Podlaskie Voivodeship, Poland, 26.01.2014, T. Tumiel; 3: Västerås, Sweden, 14.02.2015, M. Litsgård; FCs, 1: Västergötland, Sweden, 04.08.2011, P. Åberg; 2: Länsi-Suomen Lääni, Finland, 20.08.2013, A. Lindholm; 3: Almnäs, Sweden, 14.02.2015, P. Åberg; N20, ECs, 1: Aviemore, Great Britain, 12.12.2014, R. Martin; 2: Aviemore, Great Britain, 13.12.2014, R. Martin; 3: Aviemore, Great Britain, 13.12.2014, R. Martin; FCs, 1: Abernethie, Great Britain, 08.12.2014, R. Martin; 2: Aviemore, Great Britain, 13.12.2014, R. Martin; 3: Aviemore, Great Britain, 13.12.2014, R. Martin; N21, ECs, 1: Uppsala, Sweden, 09.03.2013, J. Poelstra; 2: Vännäs, Sweden, 21.04.2013, J. Grahn; 3: Uppsala, Sweden, 31.03.2013, J. Poelstra; FCs, 1: Uppsala, Sweden, 07.09.2012, J. Poelstra; 2: Uppsala, Sweden, 23.02.2013, J. Poelstra; 3: Arnheim, Netherlands, 25.10.2013, H. van Oosten; N22, FCs, 1: Porkkalanniemi, Finland, 04.09.2010, A. Lindholm; 2: Nauvo, Finland, 23.06.2013, A. Lindholm; 3: Spithami, Estonia, 01.09.2014, A. Lindholm: N23, FCs, 1: Gelderland, Netherlands, 22.10.2013, H. van Oosten; 2: Gelderland, Netherlands, 22.10.2013, T. de Boer; 3: Gelderland, Netherlands, 25.10.2013, H. van Oosten; S2, ECs, 1: Corsica, France, 26.09.2014, S. Werner; 2: Corsica, France, 26.09.2014, S. Werner; 3: Corsica, France, 26.09.2014, S. Werner; FCs, 1: Corsica, France, 02.04.2011, T. Linjama; 2: Corsica, France, 16.09.2014, J. Honold; 3: Corsica, France, 26.09.2014, S. Werner; S3, ECs, 1: Cyprus, 30.08.2013, M. Feuersenger; 2: Cyprus, 30.08.2013, M. Feuersenger; 3: Cyprus, 30.08.2013, M. Feuersenger; FCs, 1: Cyprus, 30.08.2013, M. Feuersenger; 2: Cyprus, 26.05.2016, H.-H. Bergmann; S6, ECs, 1: Toufliht, Morocco, 19.02.2014, R. Martin; 2: Oukaimeden, Morocco, 11.03.2014, R. Martin; 3: Oukaimeden, Morocco, 11.03.2014, R. Martin; FCs, 1: Issoumar, Morocco, 19.02.2014, R. Martin; 2: Oukaimeden, Morocco, 11.03.2014, R. Martin; 3: Oukaimeden, Morocco, 11.03.2014, R. Martin; S17, FCs, 1: Borjomi-Kharagauli National Park, Georgia, 11.06.2015, B. Fischer; 2: Borjomi-Kharagauli National Park, Georgia, 11.06.2015, B. Fischer; 3: Borjomi-Kharagauli National Park, Georgia, 11.06.2015, B. Fischer; S19, FCs, 1: Rilski manastir, Bulgaria, 02.06.2014, B. Jahnke; 2: Rilomanastirska gora, Bulgaria, 20.08.2014, L. Pelikan; 3: Durmitor National Park, Montenegro, 15.09.2014, R. Martin; S22, ECs, 1: Mallorca, Spain, 22.09.2007, P. Edelaar; 2: Mallorca, Spain, 22.09.2007, P. Edelaar; 3: Mallorca, Spain, 23.09.2007, P. Edelaar; FCs, 1: Mallorca, Spain, 22.09.2007, P. Edelaar; 2: Mallorca, Spain, 24.09.2007, P. Edelaar; 3: Mallorca, Spain, 12.03.2017, J. Fischer; S23, FCs, 1: Durmitor-NP, Montenegro, 14.09.2014, R. Martin; 2: Berane, Montenegro, 3.10.2018, U. Paal; 3: Berane, Montenegro, 3.10.2018, U. Paal.

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