This is the fifth Supplement since publication of the 7th edition of the Check-list of North American Birds (American Ornithologists? Union [AOU] 1998). It summarizes decisions made by the AOU?s Committee on Classification and Nomenclature between 1 January and 31 December 2004. Changes in this Supplement fall into the following categories: (1) two species replace others presently on the list because of splitting of extralimital forms (Leptotila plumbeiceps replaces L. rufaxilla and Hylocharis humboldtii replaces H. grayi); (2) one species is removed from the Appendix and added to the main list because of new distributional information (Circus aeruginosus); (3) one species is removed from the list because of its merger with another species on the list (Motacilla lugens); (4) one species is removed from the main list and placed in the Appendix (Acridotheres cristatellus); (4) two species are removed from the families in which they were previously treated and placed in incertae sedis categories (Donacobius atricapilla and Coereba flaveola), and one family is removed from the list (Coerebidae); (6) one genus is removed from the list (Mimodes) because of its merger with another on the list (Mimus), with the consequent change of the scientific name of one species; and (7) the distribution of one species is restricted because of the removal of an extralimital population now treated as distinct (Melanerpes chrysauchen). Further, one species is added to the list of birds known to occur in the United States (Tachycineta albilinea). A few recent references are added to statements of distribution. Minor corrections are made in several citations or notes. There is one more deletion from the main list than additions to it, so the number of species in the main list becomes 2,037.
Additional publication details
Forty-sixth supplement to the American ornithologists' union check-list of North American Birds