Smew

The smew is one of the less commonly seen ducks, at least in North America and the United Kingdom. It is a rare winter visitor to the Aleutian and Pribilof islands of Alaska, and has occasionally been seen on the east and west coasts of Canada and the United States, and in the Great Lakes region.

British “twitchers” are more likely than Americans to see smews, especially in the estuaries and wetlands of south-east England. Having said that, there have been recent sightings in the north of England and in Scotland. The smew’s main breeding grounds are in Finland and Russia, and it only ventures as far as Britain between November and April, when lakes and rivers further east are likely to freeze over.

They winter in considerably greater numbers in the Netherlands and Poland. They are also found in China and Japan.

Appearance

The smew (scientific name Mergus albellus) is a small, compact duck, about 14-17 inches in length (36-43 cm). Females are somewhat smaller than males. The male is particularly striking, being mostly white but with black patches and lines on the head, body and wings that make it look piebald in flight. The female has a chestnut cap on its head, and its body is grey on the back and lighter underneath. It has less white on its wings than the male. The legs, feet and bill are grey.

The bill of the smew is short, thick and pointed, and with a jagged edge, thus making the smew the smallest of the European sawbill ducks.

Behaviour

Smews feed mainly on small fish (also invertebrates), for which the serrated bill is particularly useful. They dive from the surface and can swim underwater in pursuit of prey.

In flight the smew is fast and agile, swerving from side to side and taking off vertically from water, rather like a teal. It can be seen flying in groups in diagonal lines or V formations.

The call of the smew is a sharp “krrr” sound, but it is silent in winter.

Breeding

Smews breed from their second year, the breeding season being from May to June. Common nesting sites are holes in forest trees made by woodpeckers, although they prefer sites that are close to the ground. The clutch is usually from six to nine eggs, which hatch in about 26 days.

Smews have been known to interbreed with goldeneye ducks, which have similar nesting habits. Female smews have similar markings to female goldeneyes, so maybe the males get confused!

Despite the rarity of sightings in many places, the smew does not appear to be declining in numbers, with an estimate of the Russian population being around 7000 to 15000 pairs. Its future therefore seems assured.

© John Welford