Despite being only a rare winter visitor to the British Isles, the Smew is one of the countrys most unmistakable and easily identified duck species. Breeding across Central Asia and returning to Western Europe during winter months, smews begin to turn up on inland lakes as well as in coastal regions from November onwards.
Two males and one female Smew
Family:Ducks, geese and swans
36cm to 44cm
55cm to 69cm
500g to 800g
Male and female smews are completely unalike in appearance, but both are equally striking and immediately recognizable.
Male smews are mainly white, but have a black eye mask, black patch on the rear of the head, a black back, and two narrow black lines from the upper back to the breast. Wings are black, but patterned with grey and black.
Females have a white lower face and throat, chestnut-red crown, nape and upper neck, and dusky grey wings and back. Its flanks and lower belly are mottled grey-white.
Both males and females have grey legs and feet, a short grey bill, and a vague crest on the back of their head.
Non-breeding males moult into an eclipse plumage that is fairly similar to the colouring of a female smew, but retain their black backs and white wing patches.
Juvenile smews are also similar in appearance to females, but are browner instead of grey-black.
Compact diving ducks, smews are the smallest member of the typical mergansers, with males larger in size and weight than females.
Smew standing on rocks
Not the most vocal of waterbirds, a smew’s call is usually heard only during courtship or alarm. Male smews make a mechanical-sounding ‘kurr-ik kurr-ik’ rattle, while the alarm call of female smews is a harsher ‘krrrrr’.
Smew swimming in natural habitat
Smews feed by diving underwater to search for prey, finding aquatic insects and fish, larvae, amphibians, and some plant matter.
Water beetles and dragonflies are the main insects eaten, although crustaceans and molluscs also feature, particularly in summer.
In winter, more fish, including salmon, trout, gudgeon, herring, eels, and carp, are caught, depending on location, with both freshwater and saltwater species eaten.
Despite their small size, smews are able to catch relatively large fish, with eels up to 29 cm not posing much of a problem! Their serrated bills have a sharp, hooked end, which allows them to firmly grip hold of their prey.
Baby smews initially feed mainly on small aquatic invertebrates and their larvae, particularly dragonflies and caddisflies.
Female Smew with her baby
During the breeding season, habitats preferred by smews include freshwater lakes, pools, slow-flowing rivers and lowland oxbow lakes.
Winter habitats include large lakes, coastal lagoons and estuaries, and ice-free slow-flowing rivers.
The breeding range of smews extends from Scandinavia in the east, across Russia into eastern Siberia in the west, reaching as far north as the Arctic Circle.
The species’ winter range includes the North and Baltic seas to the east, and from central and eastern Europe to the Black and Caspian seas, as far east as Japan, the Korean peninsula and eastern China.
The leading European countries with the highest breeding populations include Finland and Russia, while little is known about the species on breeding grounds outside of Europe.
Winter visitors to western Europe are concentrated around the Netherlands and Denmark.
close-up of a Smew
Only around 125 smews visit the UK each winter, with no breeding recorded in the British Isles, so they can certainly be considered a rare visitor.
Small numbers of smews arrive in the UK each winter from Russia and Scandinavia, and arrivals are mainly spotted in coastal regions from Lincolnshire to the Severn estuary. However, they are frequently spotted on inland lakes and ponds too, rather than being purely limited to coastal waters.
Smew getting ready for take-off
Little information is available about the average expected lifespan of a smew. First-time breeding is thought to occur at 2 years of age.
Natural predators of smews across their distribution range include American mink, long-legged buzzards, rough-legged buzzards, peregrine falcons, merlins and hen harriers. In some parts of Europe, smews are shot in substantial numbers by recreational hunters.
Smews are protected by the Wildlife and Countryside Act, of 1981, which makes it an offence to knowingly kill, injure or take one into captivity.
Smews are categorised with Red status on the British Birds of Conservation Concern list, due to a 66 percent decline in numbers from 1993 to 2018.
It is considered a vulnerable species in parts of its European range, with population declines linked to habitat loss and degradation, and predation, particularly by American mink.
Female Smew resting on the rocks
Smews are cavity nesters, and frequently use abandoned hollows excavated by black woodpeckers or artificial nest boxes.
A sparse lining of feathers is added to the bottom of the hollow, but no other nesting materials are used. Nests are generally located no more than 10 m (33 ft) above ground level.
The breeding season for smews begins from April onwards, and can be delayed until June in the more northerly regions of their range. One brood is laid per season.
Smews’ eggs measure 53 mm by 38 mm (2.1 in by 1.5 in) and are cream to pale buff in colour. A typical clutch consists of between 7 and 9 eggs, which are incubated by the female alone for 26 to 28 days.
The male initially stands guard nearby, but as the incubation period progresses, leaves the breeding grounds and plays no active part in raising the ducklings once they hatch.
A seasonally monogamous species, smew pairs form on wintering grounds or during migration and remain together until the female is partway through incubating her eggs.
Males depart for moulting grounds before the young hatch, and play no active role in raising their ducklings.
Pair of Smews performing mating ritual
It’s not thought that smews are an especially aggressive species, and do not show signs of territorial behaviour, even during the breeding season.
The male defends his mate during the early incubation period, but do not defend a particular territory
Two Smews resting on the rocks
Smews are a fully migratory species, breeding in the extreme northern regions of Scandinavia, and Russia, and moving south once winter approaches.
Winter populations are found across central and western Europe, as well as in south-west Asia, particularly Iran and Uzbekistan.
Smews are winter visitors to the UK but do not breed anywhere in the British Isles. They arrive from November onwards, when conditions in their Scandinavian and Russian breeding grounds become too harsh to survive, and have all departed by early the following spring.
Male (left) and Female (right) Smews in-flight
The Smew is a sea duck. It is a small diving duck belonging to the family Anatidae.
Smew is pronounced as it is written ‘S-mew’, to rhyme with ‘new’.
The Eurasian wigeon is a medium dabbling duck that commonly breeds across northern Europe, and winters further south, including in the British Isles and occasionally in North America. Rare vagrant breeding pairs can be found in the United States, and small breeding grounds have also been established in northern England and Scotland.
This large bird arrives on our shores from Iceland to overwinter in late September, returning northwards to breed from mid March onwards.
Larger than the Common Scoter this elegant European diving duck spends much of its time at sea and is often seen in company with mixed flocks resting on the water’s surface far out from land.
Tundra Bean Goose
The tundra bean goose is the most common species of bean goose, and breeds on Russian tundra landscapes. Winters are spent grazing on open fields, marshes and agricultural land in western and central Europe and East Asia.
The Tufted Duck is the UK’s most common diving duck and a familiar sight on lakes and ponds across the country. Known for their long, hair-like tufts, these small waterfowl are fairly easy to identify but may be confused with other ducks from the Aythya genus.
Fast and erratic in flight, the Teal is the United Kingdom’s smallest wildfowl species. Despite occurring year-round in low numbers, birdwatchers are most likely to spot these tiny ducks in the winter when large numbers arrive from abroad.
One of seven American goose species, the Snow Goose is a noisy migrant that visits the Lower 48 states each winter. These beautiful birds have increased dramatically since the second half of the 20th century.
One look at the bill of a northern shoveler should be enough to provide you with an accurate species identification: their flattened shovel-like bills are unique among waterfowl and allow them to feed on tiny plankton by sweeping their heads across the water’s surface.
A large colourful duck, often found in coastal areas, the shelduck, is an established breeding waterbird in the UK. British wetlands are also a major wintering ground for the species, hosting up to 30 percent of Europe’s shelduck population each autumn.
A medium-sized diving duck, the greater scaup is known simply as the scaup in Europe, and locally as the ‘bluebill’ in North America. Only a handful of scaup breed in the UK, making it the rarest breeding duck in the British Isles.
A striking and fascinating little diving duck with an unusual courtship display, the Ruddy Duck is a widespread migrant in North America.
During the winter the population of this rare resident breeding duck increases by 55 times to that of the summer, with the influx of many thousands of others overwintering, having arrived from Russia and Eastern Europe.
Although the pink-footed goose does not breed in Britain, it is a common winter visitor, with over half a million migrating individuals arriving each autumn from breeding grounds in Iceland, Greenland and Norway’s Svalbard peninsula.
One of the world’s heaviest flying birds, and one of the most beautiful too, the Mute Swan is a majestic waterfowl with a mean reputation.
A native of Japan and China, the mandarin duck was first introduced into the UK in the 18th century and started populations in the wild in the 1930’s following escapes from captivity. The UK population is estimated to be in the region of 7,000 birds.
Instantly recognizable, the Mallard is a medium-sized dabbling duck that is familiar to people all over the world. These adaptable waterfowl are the ancestor of the modern domestic duck and are found everywhere from remote wilderness lakes to suburban backyards.
The Greylag goose is the largest grey goose from the Anser genus of the Anatidae family of waterbirds. A stout, robust and heavyweight bird, the Greylag goose is the closest wild relative and ancestor to the domestic goose. Greylag geese are distributed across much of Europe and Asia, extending into eastern Russia and China. Most populations migrate, but some are sedentary, including in much of Northern Europe.
Widespread throughout the northern hemisphere, the common merganser is the largest of the saw billed fish eating ducks. There are three sub-species with the Eurasian variant frequently known as the Goosander.
The Gargeney is a dabbling duck, slightly smaller than a mallard, and considered a rare breeder in the UK, with just over 100 pairs recorded. A fully migratory species, all garganeys spend winters in southern Africa, leaving breeding grounds as early as July, so your window for spotting one on British waters is only a very brief one.
The Gadwall is a widely distributed dabbling duck of the Anatidae family that breeds in the Northern Hemisphere. This hardy duck breeds as far north as Siberia, Alberta, Saskatchewan, and coastal Alaska and is found across both the Americas, Europe, and Asia.
The common eider (Somateria mollissima) is a large and widespread sea duck that is perhaps best known for its valuable insulating down feathers.
Regarded as being sacred by early Egyptians, this native goose of the African continent was introduced into Europe and elsewhere as an ornamental wildfowl species in the late seventeenth and eighteenth century.
The word scoter is often used to define northern sea ducks. There are six different species of scoter, all of which are monotypic and three of which are confined to North America. The Common Scoter like the Velvet Scoter can only be found in Europe and Asia whilst the Stejneger’s Scoter is a native of Asia alone.
This large bodied goose is both adaptable and social having been imported into Europe and Asia from its native lands in North America. A monogamous bird which pairs for life, it is considered a pest in some areas as being both messy and aggressive, particularly within urban environments.
A small goose species with a short, stubby bill, the brent goose (or brant, as it is known in North America), breeds in the high Arctic regions of Canada, Greenland, Siberian Russia and northern Europe’s Arctic islands. Brant spend winters along North America’s Pacific coast, part of the east coast of the US, and in north-western Europe, from the British Isles to Denmark.
Winter visitors to the UK, formerly considered a full species, but now considered a sub-species of the Tundra Swan.
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