General
Pomarine Jaeger: Large jaeger with entirely dark brown plumage except for white patches near underwing tips and on sides of undertail. Light morph has white neck, pale yellow collar, white lower breast and mottled breast band and sides. Bill is thick, heavy, and has pale base. Neck is thick. Tail has two long central feathers twisted vertically. Tail streamers are often lost during the summer. Sexes are similar. Juveniles of both morphs are brown overall with fine bars and have rounded central tail feathers.
Range and Habitat
Pomarine Jaeger: Circumpolar species found in the Arctic tundra. Breeds in the high northern areas of Alaska and Canada. Winters mostly offshore in the Atlantic and Gulf of Mexico, near the West Indies; in the Pacific, from California south; also off coasts of Africa, southeast Australia, and Central and South America; sometimes found near Hawaii.
Breeding and Nesting
Pomarine Jaeger: Two olive to brown eggs with dark brown blotches are laid in a shallow ground depression lined with plant material. Incubation ranges from 25 to 27 days and is carried out by both parents.
Foraging and Feeding
Pomarine Jaeger: It will feed almost entirely on lemmings at its breeding grounds. It will chase terns, auks or gulls until the fleeing bird is so distressed that it drops any fish it has recently caught. The jaeger promptly eats this illicitly gained meal, by catching it in mid-air or from the surface of the water. It will also eat small birds, rodents, insects, eggs and berries.
Vocalization
Pomarine Jaeger: Silent except on breeding grounds; utters a sharp "which-yew" or high-pitched "week-week."
Similar Species
Pomarine Jaeger: Parasitic Jaeger is smaller, more slender, and has smaller bill and two central tail feathers extended and pointed but not twisted.