Pomarine Jaeger

The Pomarine is a large sea bird. The Pomarine is a member of the skua family and is about the size of a herring gull.

All in a Name

The Pomarine or Pomarine Skua has the species name Stercorarius pomarinus. The Pomarine is called the pomarine jaeger in the Americas. The Pomarine is sometimes called the pomatorhine skua. The species was first described by Temminck in 1815.

Physical Characteristics

The Pomarine is about the size of a herring gull. The pomarine jaeger is the largest of the three jaeger species. Around 90% of the adults are a light morph, with a black cap and dark brown upper parts, white under parts, a white collar, and a brown band across the breast. The darker morph has the same dark coloring but brown collar and under-parts. Juveniles have a brown head and neck and barred coverts on the tail.
The Pomarine's tail has spoon shaped streamers. The long central tail feathers are lost after the breeding season, in late summer.

Behavior

The Pomarine's local population varies along with the number of lemmings and other rodents it eats. In northern Alaska, this is the major predator of the brown lemming. The Pomarine will sometimes dig to find lemming nests.
The Pomarine forages at sea by dipping to the surface to catch fish. The Pomarine will catch small birds in flight and eat them. The Pomarine sometimes harasses other birds into dropping their food before seizing and eating it. The Pomarine's diet will include carrion and refuse. The Pomarine will eat eggs and insects, especially non-breeding birds in the summer. When rodent populations are low, some birds will not breed that season. Tend to nest at four to five years of age, though younger ones may try to nest if rodents are abundant.
The Pomarine form breeding pairs before the start of the breeding season, sometimes with old mates. The breeding pair builds a nest in an indentation in the ground, lining it with vegetation. They nest on open ground. They defend their nesting territories against other jaegers. Pomarine tend to lay two eggs in their nest. The clutch may be as large as three eggs. Both parents incubate the eggs for just under four weeks. The young are fed by both parents. Their first flight is around a month of age, but they will continue to rely on the parents for food until around six weeks of age. Parents leave the breeding area as soon as the young are independent.
The Pomarine migrate individually or in small groups.
The Pomarine has a week-week call.

Habitat

The Pomarine Jaeger is a circumpolar species of the Arctic tundra. The Pomarine Jaeger primary habitat is the open sea. In the summer, the Pomarine Jaeger is on the tundra, in low-lying areas along the coast. In the winter, the Pomarine Jaeger spends much of its time on the coast of the Atlantic, West Indes, Pacific. The Pomarine Jaeger is sometimes found in southeast Australia, South America, and Africa.


Range

The Pomarine's breeding range is mostly away from the range of human activity, along the Arctic shores of Alaska and Canada.
The Pomarine is found farther offshore than the parasitic jaeger.


Trivia

The name pomarine is Greek for lid-nosed, and it refers to the sheath that covers the base of the bill.
A group of any skua, including the pomarine, is called a shishkab.