noun
duck with white specula
Refers to any duck species that has white patches (specula) on the wings. A specialized bird-watching term.
羽白は、翼に白い斑があるカモの総称です。
Hajiro is a general term for ducks with white patches on their wings.
Compound of 羽 (ha, 'wing') and 白 (shiro, 'white'), referring to the white wing patches. The reading はじろ is a rendaku form of しろ.