Starting with the 2013 field season, this three-character field holds the WRP (Wolfe-Ryder-Pyle) codes as defined in this work:
Wolfe, Jared D., Thomas B. Ryder, and Peter Pyle. Using molt cycles to categorize the age of tropical birds: an integrative new system. In J. Field Ornithol. 81(2): 186–194, 2002.
The field may be entirely blank, or it may contain three characters. The first column defines the molt cycle:
The second character qualifies the cycle.
Undergoing molts, e.g., |
“At least;” for example, |
The third character describes the plumage.