The four letter common name alpha code is is derived from the first two letters of the common first name and the first two letters of common last name. The six letter species name alpha code is derived from the first three letters of the scientific name (genus) and the first three letters of the scientific name (species). See (1) below for the rules used to create the codes..

Four-letter (for English common names) and six-letter (for scientific names) species alpha codes were developed by Pyle and DeSante (2003, North American Bird-Bander 28:64-79) to reflect A.O.U. taxonomy and nomenclature (A.O.U. 1998) as modified by Supplements 42 (Auk 117:847-858, 2000) and 43 (Auk 119:897-906, 2002). The list has been updated by Pyle and DeSante to reflect changes reported by the A.O.U from 2003 through 2006.

The Integrated Taxonomic Information System (ITIS) was established in the mid-1990�s as a cooperative project among several federal agencies to improve and expand upon taxonomic data (known as the NODC Taxonomic Code) maintained by the National Oceanographic Data Center (NODC), National Oceanic and Atmospheric Administration (NOAA).

To find the ITIS page for a bird species go to the ITIS web site advanced search and report page at http://www.itis.gov/advanced_search.html. You can enter the TSN or the common name of the bird. It will return the ITIS page for that bird. Another way to obtain the ITIS page is to use the Google search engine. Enter the string ITIS followed by the taxonomic ID, for example "ITIS 178041" will return the page for the Allen's Hummingbird.