Red-Winged Blackbirds: II. Pigmentation in Epaulets of Females

Abstract

This study describes color changes in upper secondary coverts (epaulets) of female red-winged blackbirds (Agelaius phoeniceus) in successive molts. The methods used included Munsell color chips and microscopic examination of feathers. Examination of feathers collected from these upper secondary coverts showed color pigments distributed in barbs and barbules of distal feathertips. Yellow pigments predominated in juvenile and first-winter females and orange and rust in secondwinter and older birds. Rust color resulted from dark hamuli on orange barbules; in the absence of melanin in hamuli the feather appeared orange. No appreciable color changes appeared after the second winter plumage. Females with pure red feathers were not found among the redwings studied. Effect of diet on pigmentation could not be ascertained by the methods used.