This large Asiatic bird does not breed in North America but visits the Aleutian Islands, in western Alaska, only rarely. It is larger and heavier than the more familiar Bald Eagle and its plumage is unmistakable. Sexes look alike but females are larger in body-size. Full adult plumage takes four years. Adults have pure white shoulders, thighs, and tail and an immense orange-yellow beak. Immatures are mostly brown with a mottled brown-and-white tail and a huge beak. As its name implies this bird is at home along the sea coasts.
SIZE
The Steller's Sea-Eagle is a very large raptor. Although females are larger, measurements and weights overlap considerably, except at the extremes. Combined length measurements for males and females range from 33 to 41 inches (85 to 105 centimeters). The combined wingspread ranges from 87 to 96 inches (220 to 245 centimeters). Weights range from 11 to 20 pounds (5 to 9 kilograms). One bird, of unknown sex, and kept in a zoo weighed 15.25 pounds (7 kilograms)!
MORPHS
A color morph has been reported that shows no white on the forehead, wings, and leg feathers. One authority lists the morphs as a "normal" morph and a "dark" morph. Only the "normal" phase has been reported in North America.
SPECIFIC DESCRIPTION
Adult - Perched
- large, all-white wing patches
- very large orange-yellow beak and cere
- face skin is orange-yellow
- long, white tail that appears pointed
- dark brown to black head with white patch on forehead and light to white streaks from top of head to neck
- light brown eyes
- legs are orange-yellow
Immature (First year) - Perched
- body appears all blackish-brown or very dark
- light streaking on neck and upper breast
- very large yellowish beak and cere
- face skin is yellowish
- dark brown eyes
- long, light-mottled brown tail that appears pointed
- legs are yellow
SIMILAR SPECIES
The Steller's Sea-Eagle should only be confused with the Bald and White-tailed eagle. The adult Bald Eagle has a pure white head, squarish shaped tail and lacks white patches on the wing. The adult White-tailed Eagle has a buffy-brown head and also lacks the white wing patches.
Immature Bald Eagles have much smaller beaks, pronounced white armpits (axillars), and dark borders or wide appearing bands on tail. Tail is not wedge-shaped. The immature White-tailed Eagle also has a much smaller beak, lacks the wedge-shaped tail, has buffy armpits (axillars), and shows white "spears" or "spikes" in tail feathers.
OTHER NAMES
The Steller's Sea-Eagle is also known as the "Pacific Eagle", "White-shouldered Eagle", "Big-beaked Eagle, and "Amchitka Sea Eagle."
ETYMOLOGY
The genus Haliaeetus is Greek for "sea eagle" and is formed from "halos" meaning salt, and "aetos" meaning "eagle" which refers to the bird's preferred habitat. The specific name pelagicus is Latin for "oceanic, marine," again with reference for its environment. Steller is in reference to George Wilhelm Steller, a naturalist on Bering's expedition to Alaska where the Steller's Sea-Eagle was first spotted.
MYTHOLOGY
None is known for North America, probably because the bird is so rare on the continent.