ML37017061

Age and sex

Adult Male - X

Media notes

Differentiation of Common and King Eiders will be discussed here. Evidence that this is a Common Eider, not a King Eider, consists of: (a) relatively flat-topped bill (i.e., not markedly curved) running directly up toward a relatively high (or more pointed) crown (Photo ML37017061), but King Eider has a relatively more curved bill that runs up toward a flatter (or less pointed) head (e.g., King Eider Photos ML37019481, both sexes, and ML37019351, male); (b) In Common Eider feathering above the bill extends down very close to, if not to, the nostril and is relatively pointed, but King Eider (see Photo ML37019481, with both sexes) has feathering atop the bill that does not come nearly this far toward the nostrils and that terminates relatively more broadly (or less pointedly); (c) the gape line, relative to bill base, is notably straight in line with bill in Common Eider, but in King Eider (see Photo ML37019321, both males and females), the gape line angles somewhat upward behind the bill base, giving the face the semblance of a smile (see Photos ML37019321, female, and ML37019481, both sexes). (Mnemonic: "I would smile, too, if I knew I it would get me recognized as royalty!"). (See discussion of Photo ML37019481, elsewhere herein, for an additional characteristic that can be useful in differentiating King and Common Eiders.) PLEASE NOTE: There is a long, broad area of lighter coloration near the lower edge of the mantle of this bird, and it looks like white feathering is either developing or being replaced in that area, but either could be true only of a male of this species. (I lack the familiarity of plumage-stage timing in this species to be able to feel sure about whether the light-colored feathers are emergent or being lost, but I tend to think the latter, that is, that the bird is moving further into eclipse plumage. This is because I see what look to me like fresh, dark, albeit lighter-fringed, feathers incoming in this area.) Nonethless, I have no sense of conclusiveness on this matter of the type of transitional plumage shown here.

Observation details

This individual was deemed to be a male largely in eclipse plumage. Additional commentary is supplied in association with both of the two photos of this species herewith, one of which, Photo ML37017061, shows it alone at relatively close range, and the other, Photo ML37017031, shows it more distant in the company of two King Eiders (photos of the latter individuals are provided herewith).

Technical information

Model

Canon EOS 10D

ISO

800

Focal length

300 mm

Flash

Flash did not fire

f-stop

f/11.0

Shutter speed

1/1000 sec

Dimensions

2001 pixels x 1334 pixels

Original file size

487.73 KB