North American Birds: ABA Code 1 - Page 13

This list and the ones for codes 2-6 to follow might be of more interest to hardcore birders than others, but I decided to make them anyway. For its checklist, the American Birding Association assigns a code number for each bird that has been recorded in North America; generally speaking, the higher the code number, the rarer the bird. As defined by the ABA on its website, codes 1 and 2 "include regular breeding species and visitors. There is no firm designation between Code-1 and Code-2 species, except that logically Code-1 species are more widespread and are usually more numerous." In other words, these are the most common birds in the ABA area.