General

Parasitic Jaeger Dark Morph: Medium-sized jaeger with brown body, darker cap, and pale underwing patches near tips. Light morph has white underparts with brown breast band; intermediates between dark and light morphs occur. Diamond-shaped tail has elongated, pointed central feathers. Sexes are similar. Juveniles of both morphs are brown-barred overall and have dark-tipped bills and slightly elongated central tail feathers.

Range and Habitat

Parasitic Jaeger Dark Morph: Breeds on coasts of Alaska, as well as coastal and inland tundra regions of northern Canada; also found in Greenland, Iceland, Scandinavia, and northern Russia. Spends winters on tropical oceans of the southern hemisphere.

Breeding and Nesting

Parasitic Jaeger Dark Morph: Two brown to green or blue eggs with brown spots are laid in a shallow ground depression lined with plant material. Incubation ranges from 25 to 28 days and is carried out by both parents.

Foraging and Feeding

Parasitic Jaeger Dark Morph: Eats small and medium-sized birds, bird eggs, insects, fish, rodents, and carrion. Hunts cooperatively, with one chasing a bird near the ground while another flies above to intercept dodges; also, one distracts incubating parent while the other makes off with an egg. Sometimes harasses other birds, forcing them to release small fish or other food held in their bills or crops.

Vocalization

Parasitic Jaeger: Usually silent; on breeding grounds utters a series of repeated two-syllable notes and a variety of mewing sounds.

Similar Species

Parasitic Jaeger Dark Morph: Long-tailed Jaeger is pale gray above and lacks breast band. Pomarine Jaeger is larger and bulkier with rounded central tail feathers.