Thursday, 22 February 2007

Blackbirds with white feathers

For some time now I have spotted a male blackbird with white marks on its head visiting my garden. The first time I saw it I do recall describing it to my daughter as “the Blackbird that must have knocked over a tin of white paint!” You can see why. I had no idea at all about its markings so ran a search on the web.


Partial Albino Blackbird, video 0:13 with background music, try 480p quality.


Partial albinism, shown above, on the head of this male blackbird appears to be what is going on - white feathers growing where there should be black. The RSPB website explains this condition: “Partial albinism is caused by the failure of pigmentation to reach certain feathers. While this is often hereditary, other factors such as unbalanced diet, old age and injury, or even disease and shock can cause albinism. In hereditary cases the white pattern is consistent from one moult to another, but albinism caused by environmental factors is often reversible.”

I had no idea at all about this and since discovering this information I always take a closer look at my visiting blackbirds. Athough other birds can get it too it is just much more noticeable in the blackbird and other black feathered birds like the Crow and Jackdaw. Isn’t it funny how some things go unnoticed until your attention is drawn to them – and then they are everywhere! Therefore it is not surprising that I have since noticed a white feather in the tail of one other blackbird and different white markings on the head of another.

Signs of old age - I have to admit that I did smile when I read a paragraph heading in the RSPB page: “Progressive albinism can occur as a bird gets older, in the same way as people go grey”.

For more info on the condition described above and others similar follow the links below:
http://www.rspb.org.uk/advice/watchingbirds/id/albinism/albinism.asp
http://www.rspb.org.uk/advice/watchingbirds/id/albinism/melanism.asp
http://www.rspb.org.uk/advice/watchingbirds/id/albinism/other_colour_variants.asp
http://www.bbc.co.uk/nature/animals/birds/faq/

The video, shown above, was taken in my garden on February 18th 2007.

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