Description wikipedia

The Himalayan bluetail (Tarsiger rufilatus), also called the Himalayan red-flanked bush-robin or orange-flanked bush-robin, is a small passerine bird that was formerly classed as a member of the thrush family Turdidae, but is now more generally considered to be an Old World flycatcher of Muscicapidae. While currently under review, this taxon is not current recognized as a species by BirdLife international. It is closely related to the red-flanked bluetail and was generally treated as a subspecies of it in the past, but as well as differing in its migratory behaviour (the red-flanked bluetail is a long-distance migrant), it also differs in the more intense blue colour of the adult males and the greyer colour of the females and juveniles.