Stercorarius pomarinus
The Pomarine Jaeger, *Stercorarius pomarinus*, is a robust, medium-sized seabird revered by birders for its distinctive aerial piracy and elegant flight. Adults measure 46-55 cm in body length, with unique central tail feathers adding up to 13 cm more, and boast a wingspan of 115-125 cm, weighing between 540-920 g. It exhibits polymorphic plumages, with light morphs displaying a dark cap, yellowish-white cheek patches, a dark breast band, and white underparts, while dark morphs are uniformly ...
Breeding occurs on open Arctic tundra near coastlines, freshwater lakes, or bogs, typically at low elevations. During non-breeding seasons and migration, they are pelagic, frequenting the open ocean far from land.
Their diet is highly opportunistic, primarily consisting of small mammals (especially lemmings) during the breeding season, supplemented by fish, insects, eggs, and carrion. A significant foraging method, particularly at sea, is kleptoparasitism, aggressively stealing food from other seabirds.
Pomarine Jaegers are primarily diurnal, actively hunting and foraging throughout the day, typically roosting on the ground in their breeding territories or resting on the ocean surface. Their foraging strategy is iconic, involving aggressive kleptoparasitism where they relentlessly pursue gulls, ...
The Pomarine Jaeger boasts a circumpolar breeding distribution, encompassing the Arctic tundra of North America, including Alaska and northern Canada, and across Eurasia from Siberia to Scandinavia. Following the breeding season, these birds undertake vast trans-equatorial migrations to winter pe...
Least Concern
- The Pomarine Jaeger's scientific name, *pomarinus*, is derived from the Greek "poma," meaning a lid or cover, possibly referring to the cap-like dark head plumage. - Unlike its close relatives, the Parasitic and Long-tailed Jaegers, the Pomarine Jaeger possesses unique twisted, spoon-shaped cen...