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.