The marsh harrier (Circus aeruginosus), also known as the western marsh harrier, is the largest of the harriers. It has a long tail and flies with wings held in a shallow 'V'. It is distinguishable from other harriers by its larger size, heavier build, broader wings and absence of white on the rump. Females are chocolate-brown with a golden-yellow crown and throat. Males have a brown back, gingery belly, pale head and neck, and long, grey wings with black tips. The marsh harrier nests in large reedbeds where it feeds on frogs, small mammals and birds, such as moorhen and coot. Found almost worldwide, the Americas being the only exception, the marsh harrier is now usually split into several species – the western marsh harrier (Circus aeruginosus), eastern marsh harrier (Circus spilonotus), Papuan harrier (Circusspilonotus spilothorax or Circus spilothorax), swamp harrier (Circus approximans), Réunion harrier (Circus maillardi maillardi or Circus maillardi) and Madagascar marsh harrier (Circus maillardi macrosceles or Circus macrosceles).