My family and I spent a couple days last week on Hog Island at the Audubon camp. Last month the Common Eiders were molting and looking mostly brown. Now the males are almost entirely in alternate (breeding) plumage, and much sharper. Of course, last month most of the Black Guillemots were in alternate plumage, and now they are in basic (winter) plumage. Most of the Common Loons are now in basic plumage as well. Fun to see the changes in these birds through the seasons.