A practical guide to bird watching in Sonoma County, California
(Unless otherwise indicated, all phone numbers are in the 707 area code)
What is eclipse plumage?
"Eclipse plumage" is a term usually reserved for the dull, post-breeding plumage of many ducks, especially the dabbling ducks of the genus Anas. The males of most North American duck species molt into a duller plumage in the late summer, after breeding. The molt causes a temporarily period of flightlessness as flight feathers are dropped and renewed. Eclipse lasts varying periods of time, but usually three to five weeks, according to Kaufman. Some species begin to molt into their more familiar bright plumages as soon as they are able to fly again, other species retain the duller eclipse coloration until the spring following breeding. Males may migrate to sheltered molting areas where they are better protected from predation during their flightless period, during which they are unusually vulnerable. Most ducks complete the molt into their bright plumage again before they begin to migrate south ahead of winter cold, but others (notably the teals and Northern Shoveler) may begin migration while still partially in eclipse. Males in eclipse are often confusing to new and experienced birders alike. Oddly, few guide books bother to show eclipse plumages. I hope to post examples here as I collect photographs.
Further reading:
Kaufman, Field Guide to Advanced Birding, 2011, pp. 143, 155-157
© Colin Talcroft, 2009, 2010, 2011, 2012
Unless noted, all photos by the author. If you would like to use one of my images, please ask for permission for non-commercial use with proper credit or commercial use with proper compensation.