The Lynford Arboretum Crossbill with white wing bars

Another crossbill conundrum

by Martin G.

male crossbill with white wing-bars, Lynford Arboretum, Norfolk by Dave Astins

This is a rapid fire post. Too much a goin’ on. A rare Arctic Alcid to look for in the morning. Lynford Arboretum in Norfolk had pucka Two-barred Crossbill ’till maybe around mid October. Look like reports since that period have however involved the photo photographed and shown above and below. Came to my attention in twitter post and chat with Jonny Rankin and Dawn Balmer. Previously (as pointed out by Nick Watmough, below) flagged up as peculiar by Graham Clarke on his blog.  in early November.

This one wasn’t doesn’t look right, immediately suggesting something that looked intermediate between Common Crossbill and Two-barred Crossbill. Jonny, Rob Wilson, Dawn Balmer, Dave Astins (who all saw the bird in the field) and Keith Betton all engaged in the convo also on Facebook and I don’t think any thought it was a Two barred. It was of interest to me having seen a very similar bird back in the early 1990’s – also at a sight which held a real Two-barred Crossbill, at Bedgebury in Kent. I wrote on note on that bird which was published with Billy Morton sketch in Birding World. Years later I came across a specimen in the British Museum. It looked very much like the Kent bird, and seems similar to this Norfolk male. The specimen (of unknown origin) seemed ‘intermediate in plumage and biometrics between Common and Two-barred. Whether intermediate means just extreme wing-barred Common , or hybrid type, I don’t know. Both I think are possibilities

All those seeing the Lynford bird report only hearing Common Crossbill calls- no tooting :).

Recording of any calls coming definitely from this wing barred bird would be very interesting.

 

1426268_10152479211933849_1281731900_nmale crossbill with white wing-bars, Lynford Arboretum, Norfolk. Rob Wilson


male crossbill with white wing-bars, Lynford Arboretum, Norfolk by Dave Astins

crossbill various museum

 

There are more details on the ‘intermediate’ looking specimen above, included in a note in Birding World Vol. 10 no. 2. More on that again I guess.

 

in haste…

23 thoughts on “The Lynford Arboretum Crossbill with white wing bars

    1. Simon Rix

      I can’t see that there is anything wrong with the tertial pattern on this bird re. Two-barred. 1 c.y birds have very thin (even non existent) white edges to the tertials as can be seen here:
      http://oslobirder.blogspot.no/2013/11/oslo-botanisk-garden-shines.html
      It is the shape and extent of the wing bars that seems more the problem with this bird plus the bill looks to be too large. Note though that earlier in the autumn there were Two-barred Crossbills photographed in both Norway and Sweden where the white wing bars had been worn off so it is important to assess state of wear.

      Reply
  1. Lee Evans

    Martin, a lot of mistakes in here, presumably as written in such haste. I have seen a few birds like this is in UK including 2 that were in Buckinghamshire when we had a single genuine male TBC. It also reminds me of an odd-looking male ‘Two-barred Crossbill’ that I saw at Slufter’s Inclosure, New Forest, in the 1980’s. Whether or not these are genuine intergrades or just well-marked Common Crossbills is open to conjecture.

    Reply
    1. Martin Garner Post author

      Thanks for checking my spelling Lee :). I see I spelt Dawn’s surname incorrectly (now corrected) but otherwise can’t see what you mean?

      Cheers Martin

      Reply
  2. Robin Chittenden

    While at Lynford on 8th November was shown a photo of a normal male Two-barred Crossbill seen seen briefly that day. The contentious one with wing-bars was seen several times that day and a ropey photo is at http://www.birdforum.net/attachment.php?attachmentid=471896&d=1383933493

    It was courting a female Common Crossbill. If you would like a copy to illustrate your blog please let me know. I have a few other record shots of this bird.

    Thanks

    Robin

    Reply
  3. Owen Foley

    Hi Martin,

    Came across this bird on Graham’s FB discussion a couple of weeks ago.
    Seems this bird has been causing trouble for a while now.

    Thought it best, for the sake of gathering all the shots in one place, to post the images of them here. Perhaps you could add them in.

    This bird morphs between shots. In some it looks strong billed, in others weak. In some orangey red, in others crimson.

    A birdforum discussion of it here.
    http://www.birdforum.net/showthread.php?t=271838

    Images I found.

    http://farm4.staticflickr.com/3814/10576691983_38a27c5ea5_o.jpg

    http://farm3.staticflickr.com/2850/10576472904_076782e823_o.jpg

    http://farm6.staticflickr.com/5493/10576463404_bdbf9f113a_o.jpg

    http://www.rarebirdalert.co.uk/RealData/gallery_show.asp?galleryid=22256&page=1&sort=4&fast_filter=3

    http://www.rarebirdalert.co.uk/RealData/gallery_show.asp?galleryid=22139&page=1&sort=4&SpeciesID=16650&L1=0&L2=1&L3=2

    http://www.rarebirdalert.co.uk/RealData/gallery_show.asp?galleryid=22511&page=1&sort=4&SpeciesID=0&L1=0&L2=1&L3=2

    For comparison, I include two shots of a weakly marked bird from Shetland.

    http://01271bfede0954168758-da1041207dde8e2d0a75af6fbedebedf.r83.cf1.rackcdn.com/20130720105004607.jpg

    http://01271bfede0954168758-da1041207dde8e2d0a75af6fbedebedf.r83.cf1.rackcdn.com/20130720105611592.jpg

    Regards

    Reply
  4. Owen Foley

    Further to earlier, I cannot help but wonder if this bird is a first year, having been one of the very narrow wingbarred juveniles that were present at this site during the summer?

    Owen

    Reply
  5. Matt Young

    I certainly would not rule out 1 cy Two-barred Crossbill. Any recordings at all….they should be easy to tell apart!!

    Reply
  6. AW

    There are folk out there with considerably more experience and skill in Crossbill id than me and the following is from a ringer’s perspective and relates to the aging of this bird which may help in assigning it to species. A couple of the photos appear to show two generations of feathers in the greater coverts, the outer coverts being browner with narrow white tips and the inner blacker with broad white tips. The outers also appear slightly shorter than the inners. At the risk of preaching to converted, this occurs commonly in passerines and is the result of post juvenile moult where the bird as an immature replaces head, body and some inner coverts and retains remiges, rectirices and a number of outer greater coverts (hence the contrast and also the varying width of the wing bar). The narrow white tips to tertials and outer greater coverts are therefore likely to be a combined result of juvenile feather pattern and 12 months plus wear. The replaced inner greater coverts are marginally fresher and adult in type and as such have broader white tips. According to Svensson TBCbill, having undergone a partial moult in its first winter undertakes complete annual winter moults there on i.e. following the bird’s second moult it’s feathers will all be the same age with no contrast. Therefore, the suggestion that the bird is first year appears to be valid.

    Reply
  7. Dipper

    I saw what I think was this bird on Saturday in the company of many other birders. The thing that really stood out apart from the wing bars is that its a vivid raspberry colour, easy to pick out head on from the accompanying Common Crossbills. So any Common Crossbill theories need to explain why this bird doesn’t just have wing bars but is a completely different colour too.

    Reply
  8. Dawn Balmer

    Looking at photos of other Two-barred Crossbills in the country at the moment (eg http://www.shropshirebirds.com/gallery_latest.htm) they seem to have stonking white wing bars suggesting they have ‘adult type’ greater coverts.

    BWP suggests that in juvenile Two-barred Crossbills there is a partial moult involving ‘head, body, and lesser as well as some to all median and greater upper wing coverts; occasionally a few tertials’ which usually takes place June-November, depending on time of fledging.

    I saw this bird on Sunday and agree that the colour of it really stood out, however, in my opinion it appeared to have the structure of a Common Crossbill; particularly the bill didn’t look right for Two-barred.

    Reply
    1. Simon Rix

      Interesting picture. Those dark uppertail coverts with pale fringes (not quite white but much paler than rump) are a definite Two-barred feature and are as far as I know not shown by Common Crossbill.

      Reply
      1. Jon Theobald

        Hi I took the picture and I noticed that feature too. I guess you get lots of experience of seeing crossbill variations in Norway.

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