The Bird Book/Skuas and Jaegers

The Bird Book by Chester A. Reed
Skuas and Jaegers: Family Stercoraridse


LONG-WINGED SWIMMERS. Order II. LONGIPENNES SKUA AND JAEGERS. Family STERCORARIIDAE

Skuas and Jaegers are birds having a Gull or Tern-like form and with a hooked bill, the base of which is covered with a scaly shield. They have webbed feet and are able to swim and dive, but they commonly get their living by preying upon the Gulls and Terns, overtaking them by their superior speed and by their strength and ferocity forcing them to relinquish their food. The Jaegers especially are one of the swiftest and most graceful birds that fly.

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THE BIRD BOOK

35. SKUA. Megalestris skua.

Range. Coasts and islands of the North Atlantic, chiefly on the European side; rare on the Atlantic coast of North America.

Skuas are large (22 inches in length) and very powerfully built birds, having the general form of a Gull. Their whole plumage is a dingy brownish black color, palest below. Breeds in Iceland and possibly on some of the islands in Hudson Strait. The nest is a hollow on the ground in

Skua Pomarine Jaeger

Olive brown

the marsh grass and is lined with grass. The two eggs which they lay have an olive greenish ground, spotted with dark brown. Size 2.75 x 1.90.

36. POMARINE JAEGER. Stercorarius pomarinus.

Range. Northern Hemisphere, breeding within the Arctic Circle, more commonly in the Old World.

In the breeding plumage, this Jaeger has the crown and face blackish; back and sides of head, throat and under parts pure white, except the pointed stiffened feathers of the neck which are yellow. Back, wings and tail blackish, the latter with the two middle feathers lengthened about four inches beyond the rest of the tail, and broad to the tips, which are twisted so that the feathers are vertical. They breed throughout the Arctic regions, but not as commonly in America as the following

species. The nest is on the ground D olive brown

in the marsh grass and is made of

grass and moss. They lay two and rarely three eggs of an olive brown or greenish color. These are spotted with brown and black. Size 2.20x1.70.

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LONG-WINGED SWIMMERS

37- PARASITIC JAEGER. Stercorarius parasiticus

Range. Northern Hemisphere, wintering south to South America.

The Parasitic Jaeger is very similar to the Pomarine except that the central tail feathers are pointed and are straight instead of twisted. It is an abundant bird in Alaska, breeding from the Aleutian Chain northward.

They locate their nests in the highest parts of marshy places, the nest itself being only a depression in the ground lined with grass and moss. The two eggs have an olive greenish or brownish ground and are marked with various shades of brown and black. Size 2.15 x 1.65.

Brownish

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Stercorarius

in winter to

LONG-TAILED JAEGER. longicaudus.

Range. Arctic America ; south South America Parastic Jaeger

The long-tailed Jaeger is, according to length, Long-tailed Jseger

the largest of the Jaegers, being 21 in. long; this is, however, due to the long sharp pointed central pair of tail feathers, which extend about eight inches beyond the others, and from the most noticeable distinguishing point from the former species. The plumages that have been described are the light phases; all the Jaegers have a dark phase in which the plumage is a nearly uniform sooty brown, lightest below.

The Long-tailed Jaegers are the most numerous in Alaska and are even more graceful in flight than are the Gulls and Terns, floating, skimming, sailing, plunging, and darting about with incredible swiftness and ease. Like the others of this family, they pilfer their food from the Gulls, and are also very destructive to young birds and eggs. Their eggs are either laid on the bare ground or in a slight depression, scantily lined with

grasses. The eggs are indistinguishable from those of the preceding species except that they average a trifle smaller. Size 2.10 x 1.50.

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THE BIRD BOOK