Sex dimorphism in adult Azov caspian gull Larus cachinnans cachinnans Pallas, 1780

The taxonomic status of the gulls from cachinnans group is not clear and still discussed. Many authors described field features of this forms. Still heated discussions under cachinnans could be caused among other thihgs by poorly known population variability within of the Caspian Gull. There are only two papers describing just some aspects of the morphometric problems. In this paper we show morphological variability within analyzed group and features to recognize sexes.