So that’s what it looked like!
Sheffield’s Great White Redpoll. The second record this year.
Some of Sheffield bird ringers (SORBY Breck) caught a fascinating Redpoll yesterday. Geoff Mawson and David Williams sent photos through. It’s a corker.
Now here’s the weird thing. I took one look at the pictures and immediately thought of last winters bird. December 2009 and January 2010, a ‘white’ redpoll possibly Arctic was very poorly seen at 70 Acre Hill. Eventually I managed some reasonable views. It was clearly stunning looking with lots of white, but more semi-albino than Arctic, but what a redpoll! It looked just like the bird in these photos.
Remarkable thing is the bird in these photos had a ring on yesterday. So it was a ‘control’. It was rung last year as a normal looking first winter! Presumably something in the local gene pool means that its first adult moult produced these amazing white feathering- and there are more from the same gene pool.
Never heard of that before, a bird ‘moulting into albinism (or leucism).
All photos of ‘white’ Lesser Redpoll, trapped 70 Acre Hill Sheffield, 14th November 2010. Geoff Mawson.
No, albinism is genetically determined, it would be albino from hatching (well, fertilisation really).
Leucism, yes, that might be a goer, but even that is genetic and generalised.
Mind you, I’m no expert…
There is a series of pics of a ringed herring gull that gradually morphed from a normal juv to a leucistic adult here: http://www.tarsiger.com/gallery/index.php?pic_id=sampsa1256556981&lang=fin
Maybe next time that redpoll is controlled it will be the ultimate snowball!
Geoff
Just to be clear, is it the case that this redpoll was trapped and ringed as a ‘normal’ first-winter Lesser Redpoll last winter (presumably based on plumage characters and measurements), and has now metamorphosed into this white beast? I’d love to know what could cause such a rare condition, and whether or not it has been documented before. Interestingly, most of the wing and tail feathers seem relatively unaffected, despite changes to the body plumage …
Hi Dominic- Yes, that is exactly my understanding.
The condition is know in aviculture as a “progressive pied”, this type of birds are born normal and gradually became more “pied” (leucistic) true molt. It can be a genetically transmissive trait or not.
Hi Martin,
What a bird! Interestingly following up a neighbours report of a “white” odd finch in her garden up the road from me in north central Derbyshire last winter I came upon a partial albino/leucistic Lesser Redpoll. Not quite as extreme as this one but a very interesting bird with a pure white rump etc was but had just a few more brown/streaky patches over the body in random areas……. Could have been called as Arctic by the unwary on brief views. On that bird as this most of the wing and tail feathers were “normal” it being the body that had large amounts of white areas. Unfortunately it didn’t show whilst I was there with a camera!
This bird though is a WOW! What a looker! Never come across this type of acquired albinism/leucism before. I was always under the impression it was genetic from conception/hatching as Russ says…… I wonder if some other factor is at work here as well?
I thoroughly enjoyed the photos and post!
Another one:
http://www.netfugl.dk/pictures.php?id=showpicture&picture_id=36885
Some more here as well:
http://www.artportalen.se/birds
(You have to go to the Image Archive and then search for ‘Grasiska’ – photos on pages 2,3,5 and 6 at least)
22 Jan 2011 in Grenoside. Is the ringed bird the same one? Detailson ring difficult to make out, bit there is a ’1′ on it.
I have several photos, but do not know how to uplad them.
Hi Vince
can you email them? martin.go@virgin.net also how many Redpolls did you see and where- might take a look in the week. Cheers Martin