4.3. Rules for the six-letter code system
As with the Bird Banding Lab's four-letter codes,
six-letter codes are derived by abbreviating the name of
the bird. Names are not limited to standard AOU species
names. Codes may be based on obsolete names (e.g.,
Short-billed Marsh Wren), subspecies names (Peale's
Falcon), color morphs (Blue Goose), or even vague
categories like “raptor” or
“Empidonax sp.”
Birds with one-word names are abbreviated by taking
the initial letters of the name:
For two-word names, take the first three letters of
the first word and the first three letters of the
last word. Hyphenated words are always treated as
separate words:
For three-word names, take two letters from the first
word, one from the second, and three from the third:
For four or more words, take one letter each from the
first three words, then the first three letters of
the last word:
To reduce the number of conflicts, certain similar
color names are abbreviated in standard ways:
Examples:
