Bird extinction

Bird extinction is the complete elimination of all species members within the taxonomic class Aves. Out of all known bird species, (approximately 11,154), 159 (1.4%) have become extinct, with 226 (2%) being critically endangered. There is a general consensus among ornithologists that if anthropogenic activities continue as current trends suggest, one-third of all bird species, and an even greater proportion of bird populations, will be rendered extinct by the end of the 21st century.