Ring-necked Duck

I mentioned in a prior post that I had not done much winter birding in many years.  I made up for it this year with several visits to Belle Isle - even though I saw essentially the same species each time.  This year's cold weather made for lots of ice on our waterways and we had large congregations of waterfowl on the river.   Some species, like Ring-necked Duck (Althya collaris), I had not seen in several years - as in, when you don't go birding, you don't see birds. 

At first there were five, three males and two females.  I approached carefully and not too closely, but one of the males became jittery and flew off.  This left me with two pairs who were wary but still stuck around.

The long neck and head of the male Ring-neck Duck reveal a bouffant appearance when viewed from behind.  The bird on the left displays this amusingly.  This is suggested in the lateral view with the arrow pointing to that slight head feather indentation of the bird on the right. I imagine that this serves a similar function as the male Hooded Merganser's display when around female birds.   

A very handsome duck if ever there was one.

Waterfowl surprise me with their unwillingness to allow a slow approach.  All January and February, no matter how carefully I approached the river and even while still some distance away, the flotillas would turn their backs and begin their swim away from shore. I like the photo above because even at rest this female is keeping a watchful eye.

Female and male.

Is anyone else confused as to why this duck is named ring-necked?  I went on a search and found a possible answer in photos of birds in flight.  In flight the male's bright white lateral crescent thins out and is visible as a partial white ring just above the bird's open, in-flight wing. This is best viewed with a good lateral image of a bird in flight.  It's the best answer I can find for the moment.  I don't have my own Ring-necked Duck flight photo and I couldn't find one on-line that I could legally download to show this but will keep looking.