Unusual phaeomelanised plumage: a review of similar cases in different species

Abstract

Scattered records of birds with an unusual brown colour to parts of their plumage have been known for some time but, so far, the nature of this aberration has not been investigated. Aberrant reddish-brown phaeomelanin has been recorded in many species, including those whose plumage naturally contains only black eumelanin. The occurrence of a Eurasian Wryneck Jynx torquilla with such an aberration prompted further research, and a review of the records and assessment of the possible nature of the unusual phaeomelanised plumage is presented.