White-winged Scoter

The White-winged Scoter (Melanitta deglandi), is a robust sea duck, notable for its bulky shape and substantial bill. Males are predominantly black with distinctive white markings around the eye and a white speculum, while females are a more subdued brownish hue. The species is named for the white secondary flight feathers, which are a key identification feature, though these may be hidden when the bird is at rest.

Identification Tips

Adult males are unmistakable with their black plumage, accented by white around the eyes and on the wing. Their bill is a striking orange and red with a prominent black knob at the base. Females and juveniles can be identified by their brownish coloration and the feathered gape, with younger birds displaying more pronounced white facial patches and a mottled white belly.

Habitat

The White-winged Scoter breeds in the boreal forests, favoring the vicinity of seas, lakes, and rivers. It is found in woodland or tundra environments.

Distribution

This species has an extensive breeding range across North America, from Alaska to Western Canada, and is less common towards the Hudson Bay and Canadian Prairies. In winter, it migrates to temperate coastal waters, including the Great Lakes, northern United States, and southern Canadian coasts.

Behaviour

White-winged Scoters are known to form monogamous pairs, possibly maintaining long-term bonds. They exhibit a strong social structure, often gathering in large, tightly packed flocks on coastal waters. They are also known for their communal take-offs.

Breeding

Pairs form in late summer, with breeding commencing at two years of age. Nesting occurs near water bodies, with a clutch size ranging from five to eleven pinkish eggs. Males depart after the eggs are laid, while females may tend to large mixed broods post-hatching.

Similar Species

The White-winged Scoter can be differentiated from the Stejneger's Scoter by the males' browner flanks, the coloration of the bill, and the height of the bill knob. Females of both species are similar but can be distinguished by head shape and the feathering at the base of the upper mandible.

Diet and Feeding

A benthic feeder, the White-winged Scoter dives to various depths depending on the environment. It consumes crustaceans and insects in freshwater, and molluscs and crustaceans in saltwater. Its gizzard is adapted to crush hard-shelled prey.

Conservation status

The White-winged Scoter is currently listed as Least Concern by the IUCN, indicating that it is not at immediate risk of population decline.