Common Eiders (Somartria mollissima), North Hampton, NH. December 3rd, 2004.
The head and bill shapes of these two male Eiders appear noticeably different in these images, with the 'orange-billed' male showing more prominent mantle sails. The difference in bill color is
particularly evident in these shots. So is this sort of variation normal in the Atlantic North American form S.m.dresseri? Could two different forms be shown here?
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| The orange-billed male is in the foreground, though the bill color isn't particularly evident in this shot. | Note the 'orange-billed' male is at the rear of the shot showing the rather curious head and bill profile. More images of the male in the foreground can be found here. |