HomeGlossary Bird topography Casque A helmet-like growth on top of the bill or head. Found in hornbills and cassowaries; its size and colour are key identification features. Bird topographyRelated termsFull glossary Lores The area between the eye and the base of the bill. Speculum A bright, often iridescent patch on the secondaries of many ducks. Coverts Small feathers that overlap the bases of the flight and tail feathers, on both upper and under surfaces. Mantle The upper back, between the nape and the scapulars. Nape The back of the neck. Cere The bare, often coloured skin at the base of the upper bill in raptors, parrots and pigeons.
Coverts Small feathers that overlap the bases of the flight and tail feathers, on both upper and under surfaces.