Colour problems

 Many of you will be familiar with birds whose feathers are not exactly coloured as expected. I've posted pictures recently of leucistic birds where the whole bird is a yellow tinge. And albino birds where all the bird is white are reasonably well known about. These are major genetic mutations affection the whole bird.

However, there are lots of more complex, but restricted colour problems in birds, and we've had two of these in the last few days.

First this male Blackbird had on one feather on each wing pure white...

I've seen several similar anomalies like this so it's cause must be quite a regular one. However, I've never before seen a Greenfich with the following colour abnormality.....

Why this is so interesting is that at first sight we could be looking at another bird with patches of white in the plumage. But look carefully and you will see the forehead nearest the camera is much greener than the rest of the head. I have no idea what to call this or how it has happened. Answers on a postcard please........