This is a list of Falconiformes and Accipitriformes species by global population. There are 163 species in the order Accipitriformes assessed as least concern. This occurs in Passeriformes, Columbiformes, falconiformes, accipitriformes, Galliformes and a vast majority of birds. The phylogeny of Accipitriformes is complex and difficult to unravel. For a complete list of species, see list of Accipitriformes species. There are 26 species in the order Accipitriformes assessed as vulnerable. The International Ornithological Congress (IOC) recognizes 266 species of Accipitriformes distributed among four families. Accipitriformes includes most of the diurnal birds of prey. Almost all Accipitriformes are carnivorous, hunting by sight during the day or at twilight. The British Ornithologists' Union already recognized the Accipitriformes, and has adopted the move of Falconiformes.