Wednesday 11 December 2013

More on the Broomhead Parrot Crossbill

Dave Hursthouse has sent the following contribution.

After studying thirteen Parrot Crossbills in North Notts this morning, I'm drawn back to the image of the crossbill discussed yesterday on the Barnsley Birders forum. Three of the Parrots seen earlier today show typical bulky bills without extensive tips, which is what most birders expect to seen when looking for Parrots, thought many of the others in the flock, show tips with various amounts of extension, they all, however, retained the single most important factor, the bill shape of Parrot Crossbill! Some of the Notts birds had an upper mandible tip as extensive, or more so, than that of the upper mandible tip of the Barnsley bird. At least two of the Notts birds show very noticeable crossed mandible tips, which is not that often associated with Parrots. Age is the most probable explanation. Looking back at the 1982 Parrots in the Sheffield / Barnsley area, many of these didn't show extensive mandible tips, actually the lower mandibles on many looked stubby in appearance, and to some degree the bills of many of the 82 birds differ slightly from the appearance of today's birds, this is most probably age related fact. As with the local Two-barred Crossbills, they were this years birds, which have moulted out to various depths of plumage stages of adult plumage, whereas, many of the 82 Parrots were older adults. If it was possible to look at the Barnsley bird next December (2014), and so on year after year, the mandible tips would progressively become less extensive and blunter tipped year on year, brought about through the constant feeding on hard to open cones. Therefore, taking into consideration the Notts Parrots, in my opinion, the Barnsley birds is without doubt a first-winter male adult red plumage Parrot Crossbill! Parrots often prefer to be among their own sort, so get out there and look, because if there's one, there's almost certain to be others!!

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