Ducks moult twice a year and some of our most colourful are losing their finery. The summer moult after breeding sees the drakes taking on a less conspicuous plumage, similar to the ducks — for a short period they cannot fly because they drop all their flight feathers. So it does make sense to wear camouflage rather than party frocks.
We usually call this drab phase eclipse plumage. Partying resumes in the autumn!
