The Alpine chough nests higher than any other bird on Earth
Climbers on Mount Everest have been followed by Alpine choughs at 8,200 metres. This glossy black crow with a yellow bill has nested at 6,500 metres, higher than any other bird, and its eggs are adapted to thin air. Its cousin, the red-billed chough, has been recorded on Everest at 7,950 metres.
There are only two true choughs: the red-billed and the Alpine, or yellow-billed. Both are black crows with bright bills and red legs, living in mountains and sea cliffs from Morocco and Spain across the Alps and Central Asia to the Himalayas and western China. They pair for life, return to the same cliff crevices to nest, and lay three to five eggs. Where they share mountains, the Alpine species breeds higher, being better suited to a high-altitude diet.
Their names carry history. Chough first described the jackdaw, imitating its call, before shifting to the red-billed bird, once common in Cornwall and known as the Cornish chough. Linnaeus originally grouped the red-billed chough with hoopoes and ibises for its curved bill. The genus name Pyrrhocorax means flame-coloured raven. Australia's white-winged chough is a different family entirely, a case of similar shapes evolving separately.
Both are spectacular fliers, riding cliff updraughts, then diving and rolling with wings folded. They feed in flocks on short grass, probing for beetles, grubs and ants; the red-billed chough usually digs 2 to 3 centimetres down but can reach 20. Alpine choughs lean on berries when insects are scarce and readily raid ski resorts and picnic sites, and skiing above 3,000 metres in the Alps has let more of them winter up high.
Changing farming practices are the main threat, breaking ranges into fragments, though neither species is globally threatened. In northern Spain red-billed choughs choose to nest near colonies of lesser kestrels, insect-eating falcons whose presence deters bigger predators and raises the choughs' breeding success.
Source: Chough
