This book treats all of the 1695 species of resident and migrant birds known to have been reliably recorded in Colombia and on its island possessions of Gorgona and Malpelo prior to 1984. A number of additional species reported for the Colombian islands of San Andrés and Providencia in the Caribeean are listed in appendix II. An additional 133 species described in the notes to the species accounts probably occur in Colombia but have not been recorded within its boundaries as yet. A few of these can be found on the south bank of the Amazon opposite Colombia but are not known to cross the Amazon.