Monday 23 November 2020

Interesting Crossbills

Over the weekend Helen and I came across a flock of around 25-30 Crossbills on East Budleigh Common. Whilst watching the flock I was struck by at least one bird which appeared to show a fairly large looking bill but I was very aware of the poor light and I didn't have my camera. The flock then disappeared but I did get some sound recordings. 
I returned on Sunday with my camera to find the flock still present and I obtained some photos and more sound recordings. The weather was quite wet, so I focused on getting as many photos as possible rather than taking time to study the birds in the field.

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!

Bird 1 male

Bird 2 female

Bird 2 female

Bird 3 female and Bird 4 wing-barred

Bird 4 wing-barred

Bird 4 wing-barred

Bird 4 wing-barred

Bird 5 female 

Bird 6 male

Bird 7 female possibly same as bird 2

Male Brambling - One of at least 3 birds in same area as Crossbills

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