Tags: Animals & Nature, Threatened & Endangered Species, Top 5 Most, The United States
Sources: Birdlife International. (2013). "Saving the World's Most Threatened Birds."
List Notes: Data is the top 5 most critically endangered bird species as of the year 2013. Number of Mature Individuals is the number of mature individuals left in the wild. Data is latest available as of October 2015.
Please note: According to Birdlife International, Some Critically Endangered species now have tiny populations and are on the very brink of extinction. Others are so rare that precise population estimates are unavailable, but probably number fewer than 50 mature individuals, e.g. Chinese Crested Tern (China), SÃ¢o TomÃ© Fiscal (SÃ¢o TomÃ© e PrÃncipe) and Cozumel Thrasher (Mexico).