One of the most exciting things about budgies, is that some mutations change colours as they age. A young, couple of months old bird, can be one colour and then change sometimes completely so it doesn't look like the same bird anymore. I guess, if it had not happened to my own birds, I wouldn't have believed it, because in some cases the difference is huge!
Take a look at budgies below. Some of them are mine, some I found on the Internet.
Has it happened to your bird? I'd love to see it or even add it to the website! Send me some pictures to budgie.bubble.blog@gmail.com
It applies only to certain budgie mutation that is called Yellow Face type 2, single factor. Briefly speaking - a bird's base colours are blue and white but there is also a yellow gene that comes out after a first moult (around 4 months old) and affects a bird's colouring. It doesn't happen to all bird though, only this certain mutation.
What is the different mutation of budgies?