This is a master list pertaining to lists of endemic birds. As applied to birds, the term "endemic" refers to any species found only within a defined geographical area. There is no upper limit for the area; it would not be incorrect to refer to all bird species as endemic to Earth. In practice, the largest areas for which the term is in common use are countries and geographical regions. An Endemic Bird Area (EBA), a term devised by BirdLife International, is a geographical (rather than political) region of the world that contains two or more restricted-range (of no more than 50,000 km2) species, while a "secondary area" contains one restricted-range species.