The codes are written in capital letters, and look like, e.g., MODO for mourning dove.
The Institute for Bird Populations codes were created in 2003[2] with the goal of addressing shortcomings of the BBL codes: Additionally the IBP list expands coverage beyond Canada and the United States to include Mexico, Central America, and the Caribbean.
It also provides a corresponding list of six-letter codes based on birds' scientific names.
The basic rules for determining the codes are simple and are similar in both systems: and so on.
Alpha codes can make data entry much more efficient, but are widely disliked as a means of general communication.