Barrow’s Goldeneye (Bucephala islandica)

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Image of a Barrow's Goldeneye in its natural habitat
Birds Goldeneye

Introduction

Barrow’s Goldeneye, Bucephala islandica, is a medium-sized diving duck of northern North America and Iceland. It breeds mainly on freshwater lakes and ponds in forested or mountainous regions, then moves to sheltered coastal waters or unfrozen inland lakes during winter. The species is recognised for the male’s dark, glossy head, white facial crescent and bright yellow eye.

Physical Description

Barrow’s Goldeneye is a compact, stocky duck with a relatively large, angular head and a short, narrow bill. Adult males measure approximately 43–48 cm in length and have a wingspan of about 70–73 cm. Females are smaller and lighter than males.

The adult male has a dark head with a purplish gloss, a steep forehead and a distinctive white crescent between the eye and bill. The breast and underparts are white, while the back and wings are largely black with small white spots and panels. The eye is bright yellow.

The female has a grey body, a warm brown head and a partly or mostly yellow bill in North America. Females of the Icelandic population generally retain more dark colour on the bill, with yellow or orange concentrated towards the outer portion. First-year birds usually have duller eyes than adults, often appearing brownish or tan.

Range and Habitat

Barrow’s Goldeneye has a discontinuous distribution with three broadly recognised populations: western North America, eastern North America and Iceland. The largest population breeds and winters in western Canada and Alaska, with smaller breeding populations extending south through British Columbia into parts of the north-western United States, including Washington, Oregon, Montana and Wyoming.

The eastern North American population breeds mainly in the boreal forests of Québec, north of the St Lawrence Estuary and Gulf. It winters chiefly along the St Lawrence system and the Atlantic coast, reaching the Maritime provinces and Maine. Iceland supports a small, largely resident population concentrated around the north-east of the country, including the Lake Mývatn region.

During the breeding season, Barrow’s Goldeneyes use shallow freshwater lakes, ponds, beaver ponds and small sloughs in boreal, montane, subalpine and alpine landscapes. Breeding waters are usually close to mature trees that provide nesting cavities. In eastern Québec, the species is associated with small, often fishless lakes in rugged, forested uplands, including lakes at elevations above about 500 m.

In winter, many birds move to sheltered marine habitats such as bays, harbours, inlets and estuaries, particularly where mussel beds occur. Others remain on inland rivers and lakes that stay free of ice. The species generally favours shallower water than the closely related Common Goldeneye.

Behaviour and Diet

Barrow’s Goldeneye is an agile diving duck that often makes a small jump before submerging. It forages by diving for aquatic invertebrates, fish eggs, small fish and some plant material. Summer prey includes insect larvae, aquatic crustaceans, isopods, amphipods and crayfish. Vegetation such as pondweed, sedges, rushes and wild celery forms a smaller part of the diet. In winter, molluscs, including mussels and periwinkles, become more important, with small fish also taken.

Courtship may begin as early as December. Males perform a series of distinctive displays involving head-turning, head-flicking, neck movements, wing and body postures, and the characteristic backward kick of the feet. Pairs are generally monogamous during the breeding season. The male commonly defends the female and nearby area until egg-laying, after which he usually leaves.

The female selects the nest site, commonly using a cavity in a dead or ageing tree, an old woodpecker hole, a hollow tree top or, less often, a rock crevice or building. Nest boxes are also readily accepted. The nest may be some distance from the water, and the female lines it with down and breast feathers. A normal clutch contains about 6–12 eggs, incubated for approximately 29–31 days. Ducklings are precocial and generally leave the nest within two days of hatching to follow their mother to water.

Several broods may join together after hatching, with one female sometimes tending a group of ducklings. The species can live for many years, and the oldest recorded individual reached at least 18 years of age.

Identification Tips

Look for a stocky diving duck with a large, triangular or oblong head, a steep forehead and a relatively small, straight bill.

  • Adult male: identify the white crescent behind the bill, glossy dark head, bright yellow eye, black-and-white body pattern and small white spots along the dark wing.
  • Female: look for the brown head, grey body and yellow or partly yellow bill. The Icelandic form usually has less yellow on the bill than North American females.
  • Compared with Common Goldeneye: Barrow’s Goldeneye usually has a steeper forehead, a more angular head, a smaller bill and a crescent-shaped facial patch. The male Common Goldeneye generally has a rounder head and a small, rounded white spot near the bill rather than Barrow’s broad crescent.
  • Compared with Bufflehead: Barrow’s Goldeneye is larger and more heavily built. Adult male Buffleheads have a large white patch extending behind the eye, rather than the sharply defined crescent between the eye and bill seen in Barrow’s Goldeneye.

Identification is easiest when head shape, bill structure, facial markings and wing pattern are considered together. Hybrids with Common Goldeneye are uncommon but can complicate identification in areas where both species occur.

Conservation Status

Barrow’s Goldeneye is classified globally as Least Concern on the IUCN Red List. This global assessment does not mean that all populations are secure. The eastern North American population is listed as Special Concern under Canada’s Species at Risk Act because it is relatively small and concentrated in a limited number of breeding and wintering areas.

Important threats include the loss of mature trees and snags used for nesting, logging around breeding lakes, the stocking of formerly fishless lakes with fish, pollution and the risk of oil spills in major wintering areas. Hunting can also create identification risks where Barrow’s Goldeneyes occur alongside Common Goldeneyes.

Population trends are difficult to measure because much of the breeding range is remote and some surveys cannot reliably separate the two goldeneye species. Recent Canadian winter surveys show that the eastern population remains subject to active monitoring. Conservation measures include protecting breeding lakes and cavity-bearing trees, maintaining suitable riparian and forest habitat, limiting harmful access and development, monitoring wintering concentrations, and using nest boxes where natural cavities are scarce.

Frequently Asked Questions

Where does Barrow’s Goldeneye live?

It breeds mainly in Alaska, western and central Canada, parts of the north-western United States, eastern Canada and Iceland. In winter, many birds move to sheltered coastal waters, while others remain on unfrozen inland lakes and rivers.

What does Barrow’s Goldeneye eat?

Its diet consists mainly of aquatic invertebrates. It also eats molluscs, crayfish, small fish, fish eggs and limited amounts of aquatic vegetation. The importance of different foods changes between the breeding and wintering seasons.

How can Barrow’s Goldeneye be distinguished from Common Goldeneye?

Barrow’s Goldeneye usually has a steeper forehead, a more angular head, a smaller bill and a crescent-shaped white facial patch. The male Common Goldeneye generally has a rounder head and a smaller rounded facial spot.

Where does Barrow’s Goldeneye nest?

It nests in cavities in dead or mature trees, often in old woodpecker holes. It may also use hollow tree tops, rock crevices and artificial nest boxes. The nest can be some distance from the breeding lake.

Is Barrow’s Goldeneye endangered?

The species is globally classified as Least Concern, but the eastern North American population is listed as Special Concern in Canada. Local threats include forestry, loss of nesting cavities, fish stocking, pollution and oil spills.

Does Barrow’s Goldeneye occur in Iceland?

Yes. Iceland supports a small, largely resident population, especially around north-eastern wetlands such as Lake Mývatn. The species is locally known as húsönd, meaning “house duck”, because nest boxes have traditionally been provided near homes and farm buildings.

References

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