Biology

The chough is an agile flyer, and engages in spectacular aerobatics, including fast dives with wings folded back (2). The diet comprises mainly of insects, particularly beetle and fly larvae, which are found by probing the ground or dung with the bill, digging holes, and stone turning (8). They may also hide food underneath stones or plant material, and often perch on the backs of sheep to remove ticks (8). This species typically breeds in small, loose colonies, but in areas with limited nest sites they will breed singly (8). Courtship involves a display, entailing mutual preening and feeding of the female by the male. The nests are built mainly of dry vegetation, often heather, by the male, and are located on ledges inside sea caves, on sea cliffs, in mine shafts, and in abandoned buildings (8). The female lines the nest with sheep wool, which both sexes help to collect (8). Between 2 and 6 eggs are laid, which are incubated for up to 18 days (8). The male feeds both the female and his offspring, and the female helps just before the chicks leave the nest. Young choughs tend to hide under rocks and in holes after leaving the nest, only emerging to feed when they hear their parents. Five weeks after fledging, the choughs become independent (8).