diagnostics
44-55 cm, 0.9-1.1 kg. An attractive medium-sized korhaan that is usually detected by its far-carrying honking or croaking calls. Sexes differ in size and plumage colouration. In adult male, crown and front of neck blue-grey; hind neck rufous in southern races barrowii and mackenziei (but blue-grey in the northern races senegalensis, canicollis and erlangeri). Remainder of upperparts tawny-rufous, lacking distinct markings. Face white, with black patch on nape and throat. White underside diagnostic in both sexes. Females lack blue colouration and dark throat markings. Females of race barrowii distinguished by buffy face (white in other races) and darker back. Bill dusky with pinkish base. Eyes brown. Legs whitish yellow. Juvenile similar to female, but has speckled or vermiculated crown (Allan 2005i).