Identification of male Eurasian Wigeon is straightforward and should not present any identification difficulties, although male hybrids with American Wigeon may approach the appearance of pure male Eurasian Wigeon. Identification of females and immatures, however, is much more complicated given their similarity to female American Wigeon. Fortunately, Eurasian Wigeons virtually always occur with flocks of American Wigeons and, as such, it should always be possible to directly compare potential female Eurasian Wigeons to nearby female American Wigeons. The most readily apparent difference between the females of these two species is the noticeably more brown-tinged head of the female Eurasian Wigeon that does not contrast significantly with the colour of the breast. Female American Wigeon has a distinctly cold, greyish head that usually lacks any brown tones and contrasts wth the colour of the breast. Although this feature is variable, and some Eurasian Wigeons show relatively little brown wash on the head relative to others, this is still the feature that is most likely to draw attention to a potential female Eurasian Wigeon among a group of American Wigeons. Furthermore, the female American Wigeon tends to show a more pronounced dark area around the eyes (head appearing much more uniform in female Eurasian Wigeon, rarely showing a distinct darker area around the eyes) and has browner (less greyish) upperparts.
Additional features that help separate females and immatures of these two species are the lack of a narrow black border at the base of the bill in female Eurasian Wigeon (black border usually present, but obvious only at close range, in female American Wigeon) and the wholly grey axillaries and underwing coverts of female Eurasian Wigeon (axillaries and underwing coverts whitish in female American Wigeon, but this feature is visible only in flight or when an individual flaps its wings). The innermost secondary of female Eurasian Wigeons is white, rather than grey (as in American Wigeon), and often appears as a white horizontal bar separating the tertials from the iridescent speculum on the folded wing Although very subtle, slight differences in structure include the relatively smaller head of the Eurasian Wigeon, as well as its slightly longer wings that almost reach the tail tip when folded (wingtips fall short of the tail tip in American Wigeon).
Source: Cox and Barry (2005); Barry et al. (2006)
| The most commonly-heard vocalization of the Eurasian Wigeon is a strong, descending, whistled hwEEEEEEr or WHEEEOOO (often preceded by low, brief note that can be heard at close range) that is given only by the male; this call is easily heard above the calls of nearby American Wigeons and is often the first indication of the presence of this species. Other calls include a low, growling, quack-like karr that is often given in flight; this call is slightly harsher than a similar call given by American Wigeon. Source: Sibley (2000); Barry et al. (2006) |
This species is a non-breeding migrant and winter visitor to B.C.
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This species is almost always associated with medium to large flocks of American Wigeon and the foraging habits of the two species do not appear to differ. Its diet consists almost entirely of plant material during migration and winter, although it sometimes forages on fish eggs at the mouths of salmon spawning streams and in marine areas where Pacific Herring spawn. It typically forages on the stems, fruits, and leafy parts of aquatic plants, including marine and freshwater algae, and regularly moves to upland habitats to forage on the seeds and leafy parts of grasses, clovers, and various agricultural crops. Like other dabbling ducks, this species regularly engages in “tipping-up” when foraging in water, during which it submerges the head and front half of the body while raising the back end of the body, in an effort to reach plant material on the bottom of shallow water bodies (to a depth of ~20 cm). When in upland habitats, this species grazes on a variety of low grasses and forbs, often consuming seeds and small fruits where they are available. Along with American Wigeon, this species is better-adapted to grazing in upland habitats but is less well-adapted to straining food particulates from the water than other ducks in the genus Anas.
Source: Mowbray (1999)
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