To distinguish parrots in color, size and shape are notwork, color can be different, and sizes too. The main difference between the birds - cere, and on which we must distinguish parrots by sex.
You can learn and approximate age of the poultry.
When comparing the color, pay attention to the area on the beak, on which there is no tail, this is the cere.
Females change color cere more times thanmales. When they are born, it has a lighter shade. Approximately 4 months females can boast a beautiful blue cere, but by 6 months it begins to fade and brighten at all. Then the color of the neoperennoy changes to brown and remains so for life.
In male chicks cere bright and beautiful colorpurple. He gradually changed to blue, and so it remains unchanged. That's it for the blue cere and can distinguish male from female. But be careful if you have birds of different ages, you can mix, because the females budgies too short period of time cere is blue in color.