English and Scientific Alpha Codes for North American Birds through the 52nd AOU Supplement (2011).

Updated 16 September 2011

Alphabetic (“alpha”) codes, abbreviations of English or scientific bird names, have long been employed by ornithologists. They allow quicker data entry than filling out the full English or scientific name of a species and they can also serve to cross-check other recorded names or numeric data. The U.S. Bird Banding Laboratory (BBL) has long used alpha codes in banding data, and these codes have become an integral part of large ornithological programs across Canada and the United States; however, inconsistencies occur in the rules governing the alpha codes of the BBL, and their list does not include most species found exclusively in Mexico, Central America, and the Caribbean.

Therefore, a new set of four-letter (for English common names) and six-letter (for scientific names) species alpha codes were developed by Pyle and DeSante (2003) in a rigorous manner, to reflect American Ornithologists' Union (AOU) taxonomy and nomenclature, according to the seventh edition of their Check-list (AOU 1998) along with Supplements 42 and 43 (AOU 2001-2002). Pyle and DeSante (2005-2009b) updated the list to reflect changes reported by the AOU in Supplements 44-51 (AOU 2003-2010). The current list is updated through the 52nd Supplement to the AOU Check-list (AOU 2011).

We present two sets of alpha codes for use by North and Central American and Caribbean ornithologists. The first set contains four-letter codes, based on English names, broadly following the rules and strategies adopted by the BBL. This set differs from that of the BBL in two ways. First, all 2078 species recorded from the AOU area (through 2010 according to their 51st supplement) are included, as well as 98 non-species taxa (many of which were recognized by the BBL) for which standardized English names are provided. Second, standardized, species-categorization definitions and conflict-resolution formulae (Pyle and DeSante 2003) have been strictly adhered to. The second set of codes follows the same basic principles except that it contains six-letter codes based on the scientific names (genus, species, and subspecies) of the species or taxa. We hope that this second set will be useful for ornithologists, particularly those in Latin American countries, who prefer using scientific rather than English names. These two sets of codes will continue to be updated every year, following taxonomic and name changes adopted by the AOU in future annual supplements.

View or download the English and Scientific Alpha Codes for North American Birds by clicking on one of the links below. There are four formats available: three Adobe Acrobat PDF documents (sorted in 2011 AOU phylogenetic order, alphabetical order by common name, and alphabetical order by scientific name), and a Dbase file (DBF) that can be opened by this or other commonly used programs (e.g., Excel, Access, Paradox) to allow searches or modification for other purposes. In each of the lists non-species taxa are marked with a "+" and four-letter and six letter codes that do not represent first-order letter combinations (see Pyle and DeSante 2003) due to conflicts with other species having the same codes, are marked with an asterisk (*).

Contact Peter Pyle (ppyle@birdpop.org) if you would like copies of older lists.

• English and Scientific Alpha Codes for North American Birds - sorted in phylogenetic order (PDF)



• English and Scientific Alpha Codes for North American Birds - sorted alphabetically by English Name (PDF)



• English and Scientific Alpha Codes for North American Birds - sorted alphabetically by Scientific Name (PDF)



• English and Scientific Alpha Codes for North American Birds - zipped database file, sorted in phylogenetic order (DBF); downloaded and unzipped file can be opened by Excel, Access, Paradox, etc.

“+” before English name indicates a non-species taxon
* Four-letter and six-letter codes that, because of conflicts, are not "1st-order" codes are marked with an asterisk. See Pyle and DeSante, North American Bird Bander 28:64-79 (2003) for more information.

Literature Cited

American Ornithologists' Union (AOU). 1998. Check-list of North American birds, 7th ed. American Ornithologists' Union, Washington D.C. 829 pp.

American Ornithologists' Union (AOU). 2000. Forty-second supplement to the American Ornithologists' Union Check-list of North American birds. Auk 117:847-858.

American Ornithologists' Union (AOU). 2002. Forty-third supplement to the American
Ornithologists' Union Check-list of North American birds. Auk 119:897-906.

American Ornithologists' Union (AOU; R.C. Banks, et al., comps.). 2003. Forty-fourth supplement to the American Ornithologists' Union Check-list of North American birds. Auk 120:923-931.

American Ornithologists' Union (AOU; R.C. Banks, et al., comps.). 2004. Forty-fifth supplement to the American Ornithologists' Union Check-list of North American birds. Auk 121:985-995.

American Ornithologists' Union (AOU; R.C. Banks, et al., comps.). 2005. Forty-sixth supplement to the American Ornithologists' Union Check-List of North American Birds. Auk 122:1026-1031.

American Ornithologists' Union (AOU; R.C. Banks, et al., comps.). 2006. Forty-seventh supplement to the American Ornithologists' Union Check-List of North American Birds. Auk 123:926-936.

American Ornithologists' Union (AOU; R.C. Banks, et al., comps.). 2007 Forty-eighth supplement to the American Ornithologists' Union Check-List of North American Birds. Auk 124:1109-1115.

American Ornithologists' Union (AOU; R.C. Banks, et al., comps.). 2008. Forty-ninth supplement to the American Ornithologists' Union Check-List of North American Birds. Auk 125:758-768.

American Ornithologists' Union (AOU; R.T. Chesser, et al., comps.). 2009. Fiftieth supplement to the American Ornithologists' Union Check-List of North American Birds. Auk 126:705-714.

American Ornithologists' Union (AOU; R.T. Chesser, et al., comps.). 2010. Fifty-first supplement to the American Ornithologists' Union Check-List of North American Birds. Auk 127:726-744.

American Ornithologists' Union (AOU; R.T. Chesser, et al., comps.). 2011. Fifty-second supplement to the American Ornithologists' Union Check-List of North American Birds. Auk 128:600-613.

Pyle, P., and D. F. DeSante. 2003. Four-letter and six-letter alpha codes for birds recorded in the American Ornithologists' Union Check-list area. North American Bird Bander 28:64-79.

Pyle, P., and D. F. DeSante. 2005. Updates to four-letter and six-letter alpha codes based on revisions by the American Ornithologists' Union. North American Bird Bander 30:70-72.

Pyle, P., and D. F. DeSante. 2006. Updates to four-letter and six-letter alpha codes based on revisions by the American Ornithologists' Union in 2005-2006. North American Bird Bander 31:193-195.

Pyle, P., and D. F. DeSante. 2009a. Updates to four-letter and six-letter alpha codes based on revisions by the American Ornithologists' Union in 2007-2008. North American Bird Bander 34:65-67.

Pyle, P., and D. F. DeSante. 2009b. Updates to four-letter and six-letter alpha codes based on revisions by the American Ornithologists' Union in 2009. North American Bird Bander 34:109-110.