2 adverbs to describe how to moults

Do you know," added Rap after a little pause, "that when Bluebirds are little, their backs and breasts are speckled too, though afterward they moult out plain?

I have had him nearly two years, and though of course he must moult his feathers yearly, I have not observed the change of plumage, nor have I noticed that he has sung less at one period of the year than another.

2 adverbs to describe how to  moults  - Adverbs for  moults