Monday 4 February 2008

The Great Survivor

Ever hear the one about the timid Blackbird? So scared of cats he went completely...

White!

Okay, not really. He's what the experts call an 'albinistic' Blackbird, a partial albino to the rest of us (complete albinos have bizarre pink eyes - like this fledgling sparrow). Some family of mine noticed him last week during a non-birding visit to Rufford Country Park. I knew there had been infrequent reports of a 'Whitebird' at the site since it was discovered in Feb '06 - that makes him at least 3 years old - so quite the survivor. Conventional birdwatching wisdom suggests these eye-catching birds are a more conspicuous target for predators such as Sparrowhawk, a theory which makes his continued presence all the more remarkable.

Here's a brief explanation on how albinism occurs in birds...

Pure albino birds lack pigmentation and because feathers are made from keratin, which is naturally whitish in colour, their plumage is white. The absence of pigmentation also affects eye, leg and bill colour - the eye and legs appear pink owing to the blood vessels showing through, and the bill will be whitish. As well as pure albinos there are partial albinos which simply have a few white patches on their plumage or have white plumage but retain their proper eye or leg colour.

Albinism is usually a genetic condition that causes the absence of pigment, but may also be caused through malnutrition, parasites or injuries. A common belief was that too much white bread was the cause of albinism, but this is not the case. Albinism of varying degrees is quite common in Blackbirds.

from garden-bird.co.uk

In addition, I wonder if these birds are perceived as an unattractive partner by other Blackbirds. Perhaps he therefore avoids the stress, dangers and energy expense of raising a brood each year. Pure speculation on my part, I really have yet to read any research on the matter.

The bird itself is a real show off, posing almost as if aware of his glamour...

The girlfriend takes a picture.

A little donation to his upkeep.


The video: An everyday bird made glorious by the great lottery of life - genetics.

Rufford is itself a pleasant birding destination. True enough that genuine rarities are unlikely to turn up, but Hawfinches can be a notable presence in the car park during winter mornings, and during our visit all the regular woodland species showed, Nuthatch, Chaffinch, a small number of Siskin, many affording very close views. On the lake Great Crested Grebe and Tufted Duck, while Buzzard have also spread to this part of the county and can be seen overhead.

A couple of thumbnails from the day...
Robin

Rufty Tufty


Happy birding everybody!

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