The Latin Name is Bucephala islandica.

The Barrow’s Goldeneye is closely related to the Common Goldeneye. It is less common in boreal forest but it relies as heavily on habitat found in the boreal forest.

Description

This duck has a chunky body with a large head. The male is white with black back and head and a crescent shaped white spot on his face. The female is a little smaller, she is grey with a brown head. They can be difficult to distinguish from the female Common Goldeneyes. Their average size is 43-48 cm and weight is 48g-1320g. They have a wingspan of 31 inches.

They have a yellow eye and a steeply sloped forehead with a flatter crown and a peak at the forward part of the crown. They have a small, stubby beak. There are white patches on the secondary coverts which are visible in flight. The juveniles are similar to the adult females but they usually have a darker beak.

The male’s eclipse plumage is like the normal adult female but with a darker beak and sometimes a darker head.

The Barrow’s Goldeneye is silent except during courtship. The male will give a soft “ka-KAA” sound at this time and the female makes soft “cuc” noises. When in flight their wings produce a loud whistling noise.

This is a long-lived species of duck and they have been known to reach 18 years old. Females do not usually breed until they are three years old.

Habitat

The Barrow’s Goldeneye prefers alkaline wetlands with small, clear lakes and ponds that do not have too much vegetation or many fish and high invertebrate populations in the summer. They are cavity-nesting ducks and like forested habitat with mature trees, either deciduous or coniferous, that give them suitable nesting holes.

When they are migrating, Goldeneyes will stop to feed on large lakes and rivers. In the winter they can be seen in marine areas with shallow, protected bays, estuaries and large lakes with sandy, gravel or rocky beds as long as they are ice-free.

Behaviour

They are diving ducks and whole groups of Goldeneyes like to dive at the same time as they do most of their foraging under water. Typical dives are about 1-3 metres below the surface. They are aggressive, territorial birds and males will defend territories and females the areas around their broods excluding other species of birds as well as their own. The males will show spectacular and complex courtship displays.

Diet

The diet of the Goldeneye depends on whether they are in fresh or salt water. They like to eat aquatic invertebrates, crustaceans, molluscs and some seeds, green plant material, fish and fish eggs. During the breeding season, the bulk of the diet is made up of aquatic insects which is why they prefer ponds that do not contain insect-eating fish that will compete with them.

Breeding

Females tend to return to the area where they were hatched and when they start to breed will go back to the same nesting site every year. Goldeneye pairs form in late winter or early spring. Their elaborate courtship displays are often made in small groups of 5-20 birds. Normally, nests are in holes in large trees or nesting boxes but they can nest in rock crevices, abandoned buildings, burrows or in bushes on the ground if they can’t find suitable trees.

The nest will be made in an existing depression in wood chips, leaves or material from a previous nest and lined with down. Six to twelve eggs are laid and the female incubates them for 29 to 31 days. When incubation begins, the pair bond breaks up and the male starts his moult but the bond is re-established the next autumn.

The Barrow’s Goldeneye is not fussy about looking after her own young and may lay her eggs in the nest of another Goldeneye or another species of cavity-nesting duck. Re-nesting isn’t common and probably only happens when a nest has been destroyed during laying or very early in the incubation period.

The young will leave the nest a day or two after hatching and the female will take them to a place with plenty of food where they can feed themselves.  Sometimes a brood will join other broods and make large nurseries. This is most likely to happen if a brood has been abandoned early by the mother or if broods are mixed up during territorial disputes between females. The whole brood will be looked after by a single female. The young are abandoned by their mothers before they can fly, at about 5 to 6 weeks old but sometimes earlier. The young fledge at 8 to 9 weeks old.

Migration

There are three distinct migration periods, the spring migration from the winter feeding grounds to the breeding grounds, the summer migration of the males to the moulting areas and the autumn migration to the wintering areas.

The Barrow’s Goldeneye will not leave their moulting areas until later than other duck species, this will not be until the freeze has occurred. The males will arrive at the winter grounds earlier than the females and that year’s young.

Threats

Threats to the Goldeneye include forestry, urban expansion, petroleum exploration, recreation development and bioaccumulation of heavy metals in its food sources. The biggest threat is the loss of its nesting sites due to forestry and human encroachment but as it will use nesting boxes this could replace the loss of natural tree cavities. Oil spills or other environmental disasters in its breeding areas could deal a major blow to the population as there are so few members of the species and their propensity to group and breed in very small areas.