Friday, June 27, 2008

Where have all the male Mallards gone?

I worked a summer at a nature centre where waterfowl were accustomed to being fed by humans. As a result they had lost most of their fear and waddled freely among us. Starting around the beginning of July, a common question would be (from humans, not the ducks), “Where have all the male Mallards gone?”

The answer: nowhere. They were there, but incognito. Or in drag. A clue was the heaps of feathers washed up on the shore, many of them grey.

Ducks shed most of their feathers twice a year. After the breeding season, during which males look splendid in their nuptial plumage, Mallards and other dabbling ducks go through a drastic molt in which they shed most of their feathers, including their flight feathers, simultaneously. Other birds molt less frequently and more gradually. Flight feathers are molted a pair at a time, one on either side, which gives the wings a gap-toothed appearance but doesn’t significantly hinder flight. Not so in ducks; for a few weeks they are flightless.

"Don't look at me."

Mallard male, June 12.

The gaudy breeding plumage that helps male ducks attract females would also attract predators, so while flightless, males take on an “eclipse” plumage, which resembles the cryptic brown patterns of females, who must be able to hide while nest-bound or tending flightless ducklings, who are on almost everyone’s menu. One way to spy a male among the basic brown is to look at bill colour. Males will tend to retain their yellow-green bills, while female bills are orange and grey.

"Oh, when will this be over?"

Mallard male, June 25.

The flightless stage lasts only a few weeks, and long before winter males will be boldly patterned and shimmering with iridescence, itching to start the whole thing all over again.

"I feel pretty."

1 comment:

Aunt Debbi/kurts mom said...

Very interesting. Thanks for sharing. Earlier this week I learned what was up with blue headed/bald cardinals.