Hawaiian Duck

Overview

The Hawaiian duck (Anas wyvilliana) or koloa is a species of bird in the family Anatidae that is endemic to the large islands of Hawaiʻi. Taxonomically, the koloa is closely allied with the mallard (A. platyrhynchos). It differs in that it is monomorphic (with similarly marked males and females) and non-migratory. As with many duck species in the genus Anas, Hawaiian duck and mallards can interbreed and produce viable offspring, and the koloa has previously been considered an island subspecies of the mallard (Anas platyrhynchos).

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