Eclipse
A type of plumage assumed by the drakes of most species of ducks (family Anatidae) during their period of moult in late summer and autumn. All wildfowl moult all their flight feathers at once, so that they become flightless for a time, and the eclipse plumage, which resembles the dull plumage of the females, renders the otherwise brightly coloured drakes inconspicuous during a stage when they are more vulnerable than usual to predator attack.From Peter Weaver's Birdwatcher's Dictionary
Copyright © 1981 by Peter Weaver