Males Red-backed Shrike have a grey head and a typical shrike black stripe through the eye.
Females and juveniles do not have the black eye mask of the male and are dull brown.
Juveniles are similar to females but differ by the scaly pattern on the mantle (back).

1st & 2nd photo: A female. Lesvos, Greece, 28 April 2010
3rd, 4th & 5th photo: A female. Lake Koroneia, Thessaloniki, Greece, 31 July 2017