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.
Female Greater Scaup
A young Scaup
Greater Scaup, also known as the Scaup
Family:Ducks, geese and swans
42cm to 51cm
67cm to 78cm
.08g to 1.3g
Adult breeding male greater scaup have a distinctive black and white plumage, with piercing golden eyes. Their black heads have a greenish tinge, and their neck, tail and breast are a rich, glossy black. Their belly and flanks are white and their back is pale, flecked with gray. A horizontal white bar runs across the lower edge of their black wings, which is clearly visible in flight.
A male scaup’s blue-gray bill gives them their common nickname, and features a large black ‘nail’ at the tip. Their feet and legs are olive-gray to a deep lead-blue.
Close up of a Scaup duck
Before their young hatch, males depart from breeding grounds to undergo an annual molt into an ‘eclipse’ plumage, which is altogether browner than the bold black seen in breeding males. Their white flanks become heavily streaked with brown, and their bill becomes duller in color and develops some white patches around the base. Their eyes also become a more muted shade of yellow.
The plumage of female scaup is mainly a rich brown. Facial markings include a ring of white around the base of the bill. They are smaller in size than males, and can easily be told apart because of the difference in their colouring. In flight white bars can be seen along the length of the trailing edge of the wing.
Once females have raised their young, they molt into a brownish set of feathers, similar to their appearance earlier in the spring, but less vibrant and altogether more dull. In winter, a female scaup’s eyes may darken to a light brown from the pale yellow seen during the spring.
Juvenile scaup are similar in appearance to females, but have less vivid white facial markings and are a duller, paler shade of brown all over.
Male Greater Scaup
Female Greater Scaup
Classed as a medium-sized duck, scaup are smaller in size than mallards. Females are smaller and lighter in weight than males.
Scaup standing by the waters edge
Not a particularly noisy duck species, a scaup’s vocalizations are usually limited to a croaking, hoarse series of notes that make a ‘scaup’ sound, which gives the species its name.
Pair of female Greater Scaups croaking
Scaup are diving ducks, and forage for prey and aquatic vegetation by swimming underwater. Large food items are brought to the water’s surface to be eaten, and feeding continues nocturnally as well as during daylight, with tidal patterns influencing feeding times.
A scaup’s diet varies according to the season, with mussels, oysters, clams and snails being of chief importance. In summer, on their freshwater breeding habitats, scaups eat more plant matter, including pondweed, wild celery, sedges and grasses, as well as insects, invertebrates and their larvae and crustaceans.
Scaup ducklings are capable of feeding themselves as soon as they reach water for the first time, usually within 24 hours of hatching.
They begin with feeding from the water surface, taking insects and invertebrate larvae, but by their second week start to master shallow dives and expand their diet to include plant matter, crustaceans and molluscs.
Scaup can be seen foraging during the breeding season on lakes, rivers, salt bays and estuaries. During spring and summer, they are present on lakes and bogs in semi-open landscapes, up to the fringes of boreal forest and extending into tundra regions.
Once winter arrives, scaup migrate southwards, moving away from inland wetlands towards more exposed coastal bays, lagoons, and estuaries. Some inland lakes attract large numbers of overwintering scaup, in particular North America’s Great Lakes region.
Greater scaup are the most northerly scaup species, breeding in Europe and Asia from Iceland and Scandinavia in the west, eastwards across northern Russia into eastern Siberia, and the Kamchatka Peninsula.
In winter, populations experience a southward shift, with coastlines around Britain and southern Scandinavia welcoming an influx of migrating birds, and sightings commonly reported at regions bordering the Baltic, Mediterranean, Black and Caspian seas, and the Persian Gulf.
North American scaup are more numerous than their European counterparts, and breed across Alaska and across north-central Canada. Winter populations are concentrated mainly along the Atlantic coast, but are also not uncommon along the length of the Pacific coast.
Inland, many winter arrivals can be spotted in the Great Lakes region once breeding has concluded in wetlands further north.
Alaska’s tundra landscapes support the majority of North America’s breeding scaup population. In Canada, Manitoba and the Northwest Territories are the key nesting grounds, while in Europe, Russia, Iceland and Sweden are home to the largest breeding populations of scaup.
Scaup are common across North America, and become more widespread in fall, although some local declines have been identified in recent years.
In the UK, although winter visitors are not particularly extraordinary or unusual, breeding scaup are not at all common, ranking at Britain’s rarest breeding duck species. Only one or two pairs attempt to raise their young in the UK each year.
Female Greater Scaup flapping her wings
Both lesser and greater scaup are present in North America, with the former species accounting for up to 80 per cent of the continent’s combined scaup population. Greater scaup breed in the northern extremes of Canada and Alaska. Once the breeding season ends, southward migration follows, mainly to the Atlantic coast states of Delaware, Maryland and Virginia.
Winter offers the best opportunities to spot scaup in the UK, with up to 6,400 post-breeding arrivals to British waterways and wetlands, particularly in Scotland and Northern Ireland.
Lough Neagh and Lough Beg, in County Antrim, record large numbers of overwintering scaup each year, while coastal estuaries offer a chance of a sighting, in particular the Dee in Cheshire, the Solway Firth along the Scotland-England border and Scotland’s Firth of Forth and Moray Firth.
Scaup usually breed for the first time at 2 years. According to banding records, the maximum lifespan is 22 years and 1 month for a male and 19 years and 2 months for a female.
Among the leading predators of scaup are foxes, owls, skunks, raccoons and coyotes.
They are also one of the most common species hunted for sport by humans in the United States.
Scaup are a popular game bird in the US, but limits exist on when and how many can be shot at a time. They are also protected under the Federal Migratory Bird Treaty Act of 1918.
In the UK, scaup are registered as Schedule I birds under the Wildlife and Countryside Act, ng 1981, which offers their eggs, nest sites and young protection against being destroyed or damaged during the breeding season. It is illegal to knowingly kill, injure or capture the species.
Across their global range, scaup are classed as a species of least concern, and are widespread and abundant across their distribution range, with population estimates of up to 5.1 million, the majority of which are resident in North America.
Greater scaup numbers are believed to be in decline, with factors such as oil pollution, sewage, habitat degradation and human activity all threatening their long-term survival.
Due to their highly rare status as a breeding bird in the UK, scaup have Red status on the British Birds of Conservation Concern list.
Female Scaup on the edge of the water
Nests are built at ground level, amid dense vegetation cover offered by grasses and sedge and near to water. Small islands or floating platforms may occasionally be used.
The female creates a basic scrape in the ground, which is then lined with with plant matter and soft down.
In both the North American and Eurasian regions of their range, scaup nest from mid-to late May onwards, with early July being the peak time for hatching to begin.
Scaup eggs are olive to light buff in color, and have some small pitting on the surface, but are generally plain and smooth and unmarked. Eggs measure 62 mm by 43 mm (2.4 in by 1.7 in) and a typical clutch consists of between 6 and 9 eggs.
Only one brood is raised each season, with incubation (by the female alone) lasting for between 23 and 28 days.
Like many duck species, scaup are seasonally monogamous, forming pairs while still on their wintering grounds. These bonds last until up to three weeks into incubation, when the males depart for molting grounds, leaving the female to raise the young alone.
It’s unlikely that a pair will remain bonded from one year to the next in the wild, although observations of mates in captivity breeding together in subsequent years have been recorded.
Male (left) and Female (right) Greater Scaups
Some aggressive behavior may be apparent during courtship and breeding, but for the rest of the year, scaup are considered to be a relatively sociable and non-aggressive species, often joining large mixed species foraging flocks once they have finished raising their young.
During both the day and night, scaups can be found sleeping on the water of large lakes and reservoirs, with their heads tucked under their wings.
Female Scaup resting in the water
Scaup are a fully migratory species of diving duck.
Freshwater habitats are preferred for breeding, with a switch to coastal settings in the winter. In parts of Iceland, the species may be resident all year round, while in certain Scandinavian regions migrations are limited to small movements from inland lakes to coastal waters.
Greater scaup are present in North America all year round, but are a migratory species and move between their breeding grounds in Alaska and northern extremes of Arctic Canada, and wintering grounds that are dotted along the Atlantic coast of the northeastern US, as well as along the Pacific coast and in the Great Lakes regions.
A number of scaup do visit the UK in winter, but only breed in the British Isles on incredibly scarce occasions.
Scaup are diving ducks that breed in the Arctic regions of northern Canada and Eurasia.
Bluebill is another name for a greater scaup, and a little bluebill is the common name for a lesser scaup. They are diving ducks that breed in the far northern extremes of Arctic Canada, Russia and Siberia and migrate south in winter.
Scaup is pronounced ‘Scorp’, to rhyme with ‘warp’.
Lesser scaups are usually marginally smaller than greater scaups, but the key differences between the two species are mainly found in their posture, appearance, and also in their geographical range.
Lesser scaup have a more upright posture, with an almost egg-shaped head and elongated neck. Greater scaup have more rounded heads and wider necks. The black nail at the tip of a greater scaup’s bill is noticeably wider than that of the lesser scaup.
While there is some overlap between the North American breeding territories of greater and lesser scaup, the latter species is confined to the Americas, while greater scaup also breed in the extreme northern regions of Europe and Central Asia.
In North America, lesser scaup are by far the dominant species, forming up to 89 percent of the combined total population of the two species combined.
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.
Greater White-Fronted Goose
One of several similar wildfowl species in the Anser genus, Greater White-fronted Geese live up to their name with a distinctive white patch on the front of their face. The species is extremely widespread, although there are several sub-species, each with different breeding and overwintering ranges.
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.
Taiga Bean Goose
Taiga bean geese are a common sight on northern taiga marshes of Siberia and northern Scandinavia in spring and summer, before heading south into Europe each winter. Several hundred individuals spend winters in the UK, with rare vagrant visitors occasionally reported in North America.
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.
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.
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 striking and fascinating little diving duck with an unusual courtship display, the Ruddy Duck is a widespread migrant in North America.
Colourful and instantly recognisable diving ducks, red-crested pochards are present in the UK in small numbers, believed to have initially been introduced into the wild from private wildfowl collections. Some breeding does occur in Britain, although the best chance of a sighting comes with the arrival of several hundred migrants each winter.
A speedy migratory wildfowl with a hardcore hairstyle, the Red-breasted Merganser is widespread in coastal and estuarine habitats across the Northern Hemisphere.
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.
Widespread in the Northern Hemisphere, Northern Pintails are distinctive migratory waterfowl. Drakes in breeding plumage are particularly attractive, although the drabber females and non-breeding males are still identifiable by their long necks and graceful form.
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.
Sightings of wild Mandarin Ducks in the United States cause quite a stir, and it’s easy to see why. These small but eye-catching waterfowl are, in fact, native to the Far East of Asia, although their popularity as an ornamental species has resulted in their introduction to many parts of the world, including the United Kingdom.
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.
One of the most distinctive duck breeds, thanks to their extended streaming tail feathers, the long-tailed duck is a coastal waterbird that spends winters at sea, foraging for crustaceans in marine waters, after breeding on Arctic tundra landscapes.
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.
Goldeneyes are distinctive diving ducks that thrive in cold environments, breeding in boreal forests across Canada, northern Scandinavia and northern Russia. Only when the lakes and coastal areas on their summer territories begin to freeze over as fall approaches do they begin to head south to milder regions where they spend winter months foraging on inland lakes and around sheltered bays.
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.
Once decimated through overhunting and habitat destruction, the Canada Goose has rebounded to become one of North America’s most abundant and familiar wildfowl.
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.
A subspecies of the North American tundra swan, Bewick’s swans breed in Siberia and arrive in the UK each autumn. Worrying declines have been observed in the European population in recent years, and today only around 4,350 individuals migrate to the UK each winter.
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