In summary, I managed to obtain sound recordings of "flight calls" from the flock and "excited calls" of at least one bird but I was unable to attribute the recordings to specific birds that I photographed. The recordings can be heard below and all clearly suggest Common Crossbill by ear and from the spectrogram.
On reviewing my photos, most birds' bill structures seem as you would expect for a "normal" Common Crossbill, but I was interested to see at least of couple of birds appeared to show quite obvious deep bill structures. One bird in particular (bird 4 wing-barred) looks strikingly large billed in the last photo of the sequence, with a strong gradual curving of the upper mandible and quite a stout lower mandible, superficially similar to Parrot Crossbill. Despite being very rare, it would be odd to show wing bars in this species.
I am very aware of how different angles and open bills in photos can give very misleading impressions. Some of these birds appear to be large-billed Common Crossbills and the sound recordings suggest nothing other than Common Crossbill.
Despite some good photos, they were surprisingly secretive and not easy to study as they disappeared into the pine trees to feed. I had a look today but couldn't re-find them. I will keep looking because I am very keen to see the flock again as Crossbills are certainly an interesting and variable group!
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| Bird 1 male |
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| Bird 2 female |
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| Bird 2 female |
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| Bird 3 female and Bird 4 wing-barred |
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| Bird 4 wing-barred |
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| Bird 4 wing-barred |
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| Bird 4 wing-barred |
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| Bird 5 female |
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| Bird 6 male |
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| Bird 7 female possibly same as bird 2 |
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| Male Brambling - One of at least 3 birds in same area as Crossbills |
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