Although the name ‘smew’ suits this small winter-visiting duck, it could
equally conjure up the image of a character from some cartoon or children’s
story. Come to think of it, the black and white appearance of a male Smew does
have the feeling of a piece of cartoon artwork to it!
During the latter half of February there was a large number of Smew in
East Anglia, birds that had been pushed south and west by the harsh winter
weather elsewhere. We usually get the odd individual wintering here for part of
each winter but the numbers this year have been particularly good, thanks
largely to the severity of conditions east into the Russian breeding grounds.
Little bigger than a Teal, the Smew is the smallest of our sawbill
ducks, a group which includes the more familiar Red-breasted Merganser and
Goosander, the former a winter visitor and the latter an occasional breeder
within the county. Male Smew should be unmistakable, with their striking black
and white plumage and black eye patch; females are grey with a chestnut cap and
white cheeks. Many of those arriving here winter on the old gravel pits of
southern Cambridgeshire but they can become more widespread than this when
numbers are boosted by further arrivals of birds displaced by the weather from
wintering sites in the Netherlands. Movements continue throughout late winter,
the birds remaining mobile and easily displaced by freezing waterbodies and
through disturbance. We had a male on the lakes south of Thetford for several
days last month, the bird moving onto the nearby river as the lakes froze over.
Smew, like other sawbills, have bills that are lined with small,
saw-like teeth. These are used to grasp small fish caught underwater by the
bird on one of its dives. Watch a Smew hunting and you’ll notice that it
typically dips its head underwater before diving and it is thought that this
ploy helps reduce energy expenditure, the bird only diving if prey is sighted.
It is strange to think that
this small duck, so much associated with large waterbodies in winter, will
return to Russia to breed in broadleaf woodland, close to rivers, lakes and
other wetland habitats. The association with woodland comes about because the
Smew is a cavity nester, selecting tree holes some 20 foot or more above the
ground. Many of the cavities used will have been excavated by a Black
Woodpecker but Smew will also take to nest boxes erected for their use. Seeing
a male Smew here in winter is a real treat but I often wonder if I will one day
get the chance to see one on its breeding grounds. Now that would be something
really special.
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