Superb fairy wren males have breeding plumage (blue) and eclipse plumage (non- breeding plumage) which is mainly brown. They moult into breeding plumage in spring and into brown plumage in autumn, in general. As they get older they spend longer in breeding plumage each year and in good conditions older 'good quality' males (usually the dominant male in the group) may be blue all year round (ie moulting directly from blue into blue plumage).
Males that moult into eclipse plumage retain blue tails and black beak and grey lores. The upper bird in your photo is an adult male, but youngish.
Juveniles and females have brown tails, reddy beak and lores.
Subadult males moult and gain a blue tail in autumn in their first year. Some 2-4 year old males in eclipse plumage may just have a blue tail in winter. Any blue in the tail is almost always a male, yet some older females have a darker tinged grey tail.
Benj
