From the darkest corner of the forest Pairaow gets this stunner of the female Niltava. When I see this picture I wonder if the female isn't more beautiful then the male.

I would like to point out that a strong direct flash fired at these birds may disturb them.
Another photographer was using direct flash but the bird actually took off when the flash was fired.
When he saw my wifes picture he was amazed and started asking questions about the settings.

If you have to use flash please try to limit the flash output if it's dark and you're close to the bird (i.e. use high iso and open the aperture up as much as possible).
The normal technique for fill flash is to use the reflector blade of the flash unit and fire upwards in 45 degree or more, which should not disturb the bird and also give a pleasant picture which still looks natural.