Steller's Eider

Overview

Steller's Eider is the smallest and most lightly built of the eider species, breeding on arctic tundra and wintering along nearshore marine waters. Breeding males show a white head marked by a black patch around the eye and a small greenish tuft on the nape, paired with rich cinnamon underparts and a black-and-white patterned back. A glossy blue speculum on the wing adds another distinctive touch of color, visible both at rest and in flight. Females are uniformly brown, showing the blue speculum bordered by white as their main distinguishing feature.

Feather Identification

• Head pattern: A white head marked by a black patch around the eye and a small tuft of greenish feathers on the nape distinguishes the male from all other eiders.
• Underpart color: Rich cinnamon or rufous underparts contrast with the white head and patterned black-and-white back.
• Speculum: A glossy blue speculum patch on the wing, bordered by white, is present in both sexes and is one of the most reliable identification features, especially useful for females.
• Body size: Notably smaller and more compact than other eiders, with correspondingly finer, less bulky body feathering.
• Female overall tone: Females are uniformly brown with fine barring, lacking the bold head and underpart contrasts of the male, making the blue speculum an especially important identification aid.

Plumage Notes

Breeding males show a white head with a black eye patch and small nape tuft, cinnamon underparts, a black-and-white back, and a glossy blue speculum. Females are brown overall with fine barring and the same blue speculum bordered in white. Eclipse males become substantially duller and browner, losing much of the head and underpart contrast until breeding plumage returns. The species undergoes a complete post-breeding molt with a flightless period. Juveniles resemble females and gradually develop full adult male patterning.

Habitat & Range

Steller's Eiders breed on tundra ponds and wetlands in limited areas of Alaska and Siberia, nesting on the ground near shallow water. In winter, they move to nearshore marine waters, often concentrating in specific sheltered bays and coastal areas. The species has a comparatively restricted range compared to other eiders and is migratory, moving between northern breeding tundra and coastal wintering sites.

Behavior & Field Notes

Steller's Eiders forage by diving for invertebrates in shallow tundra ponds during the breeding season and in nearshore marine waters during winter. They are often seen in tight flocks, showing coordinated diving and swimming behavior. Nesting occurs on the ground near water, with females responsible for incubation and brood care. The species is generally quiet, with soft calls exchanged mainly during courtship and social interactions within flocks.