 This bird has glossy black plumage , a long curved red bill , red legs , and a loud , ringing call . It has a buoyant acrobatic flight with widely spread primaries . The red @-@ billed chough pairs for life and displays fidelity to its breeding site , which is usually a cave or crevice in a cliff face . It builds a wool @-@ lined stick nest and lays three eggs . It feeds , often in flocks , on short grazed grassland , taking mainly invertebrate prey . 
