HELP PLEASE - WHAT IS THIS BIRD?

Unknown said:

Thanks AnnaBanana   She is a lovely little thing I think you might be right as she is always with the other chaffinches. Just I haven't seen anything like her before - You live and learn!!

You're welcome! If you have the time and patience you might be able to fully identify it by listening to it's call - if she is a female chaffinch you will hear her making a high pitched "pink" call :)

'She' is very pretty with that 'marbled' effect! I have a (slightly) leucistic male blackbird - he has a few white feathers speckled on his head - it's always interesting when one crops up, it gives a unique opportunity to chart how often a single specific bird visits your garden. And they are always very endearing, I find - if just for the fact that they're 'different', it adds character :)

Diogenes said:

Can't see the photo, but if it looks like a mainly white chaffinch, it could be a leucistic one.

This happens with many species.

http://en.wikipedia.org/wiki/Leucistic

 

Hi Chez, the bird in your photo is a Leucistic Chaffinch.

There is a difference of opinion and definition of Leucism and Albinism between, "ordinary birders" and scientists. In these circles there seem to be little doubt that the term "albino" is only used if there is a complete lack of pigmentation, including soft parts. Leucism describes the various forms where there is a lack of pigmentation, but not complete. Do note that this lack can be complete in areas and still be considered leucistic, as long as other areas do have pigmentation to some extent.

Hence, "partial albino" is not used at all.

This also concurs with the ideas taught in the biology in university.

Scientifically, a bird with white patches is, in fact, leucistic.

However, this is where "ordinary birders" differ, I think in part because the term leucistic only entered the scene fairly recently in these circles. Previously, when not knowing the term leucistic, it would be logical to use the wellknown albino in a modified way; i.e. "partial albino".

However, then "leucistic" enter the scene and the confusion appears to be total.

Albino refers only to things that have two recessive genes and, therefore, no pigment anywhere.

As leucism is a spectrum between white and normal, any odd white feathers are leucistic. This could be genetic, or indeed possibly from infection/trauma and diet may also contribute to abnormalities.

If you say 'albino' people think of a pure white bird with pink eyes (no pigment anywhere), and if you say 'leucistic' then most people think of a pale, washed out bird where the colouring is diluted.

If you say 'partial albino' then people know what you mean - a bird with white patches. As such, they cannot be 'partial albino' as they do not have both recessive genes.

Leucism

Leucism is kind of the opposite of melanism.

is a condition characterised by reduced pigmentation in animals and humans. Unlike albinism, it is caused by a reduction in all types of skin pigment, not just melanin.

 

Thanks that does seem to answer my question.  Her size and shape are exactly the same as a chaffinch and she is always with the crowd so I did wonder.

Thanks a lot to all who replied - what a nice bunch you are!!!!!!