Ornithological art is taking flight at auctions on both sides of the Atlantic this month. Christie's New York is selling a rare first edition of John James Audubon's sumptuously illustrated The Birds of America, depicting more than 400 life-sized North American species in four monumental volumes, estimated value $7m to $10m. The set will be on view at Christie's Rockefeller Center galleries from 14-19 January (CLICK). Bonhams in London will auction wildlife photographer Terry Andrewartha's collection of 150 watercolours by John Cyril Harrison, who excelled at painting birds in flight. Above is Harrison's Curlews at Holkham Gap, Norfolk. The auction takes place on 25 January (title link). And don't forget Earthflight on BBC1 at 8pm this evening, soaring over Africa.