Strangers in our midst

Here at the RSPB, we often get enquiries from puzzled 'garden watchers' who have seen an odd bird in their garden.

'It looks like a blackbird, but it's got a white head.' 'One of the starlings on my feeder is all white! Is it a different species?'

Some people are a bit disappointed to be told they don't have an exotic visitor. These birds are 'common or garden' blackbirds and starlings – they just have unusual colours. A 'blackbird with a white head' is just that!

They are still relatively uncommon though and you'd have to look at a lot of normal blackbirds to find one with white, instead of black, feathers. Many examples are beautiful birds that really stand out from the crowd.

Albinistic male blackbird

It's no wonder such birds cause people to scratch their heads. If you've ever seen one, you'll know how it makes your heart race at first glance!

Here's the science…

Certain birds are quite prone to having unusual plumage, including garden favourites such as blackbirds, starlings and house sparrows.

If you've seen one of the above with white feathers, it'll have partial albinism – an absence of dark pigment in some of its feathers.

If you see a bird that looks as if its fallen down a chimney and become covered in soot, the cause is likely to be a condition called melanism. These birds have too much dark pigment in their feathers.

Standing out

I was amazed to see two unusually coloured birds on the same road this morning.

First up, as I walked to the bus stop, was a carrion crow beating its way across a field. Both of its wings were pure white!

The second stranger caught my eye as I glanced out of the bus window. A 'ghostly vision' was perched up among a group of four collared doves on a television aerial. A closer look showed it was a collared dove like the others, but was a washed out cream colour.

A bird like this caused quite a discussion on my local birdwatching forum a few years ago. The conclusion was that it had 'schizochroism'. Birds like this lack one of the normal feather colour pigments, making their colours appear slightly odd.

There's a crow at my local quarry that is called 'Sandy' because he is sandy coloured all over. He's a real head turner and an example of a bird that has a condition called leucism. This is caused by a reduction in all the types of pigment in the feathers.

A happy ending

The good news is that these 'oddballs' often survive quite happily alongside their 'normal' cousins. Most lead a relatively normal life. If you have an albino blackbird or starling in your garden, it could be around for years, so enjoy your special visitor!

Seen something strange?

Have you seen any strange looking birds in your garden? What species have you seen with albinism? Why not write a comment?