790 A PBACTICAL HANDBOOK OF BRITISH BIBDS. 



also description of juv. and 1st winter) ; shaft of 4th primary brown 

 is not certain distinction as it is sometimes brownish in Arctic Skua. 



Field -chabacters. — Bears sufficient resemblance to Arctic and 

 Pomatorhine Skuas to be recognizable as member of same genus. 

 Is most graceful and easy flier of the three, while extremely elon- 

 gated, flexible, middle tail-feathers of adult, much longer and finer 

 than corresponding feathers of Arctic Skua, furnish ready means of 

 identification. Pure white breast and buff chin are prominent when 

 bird is at rest on ground, when neck is held slightly upright. Young 

 in barred plumage can hardly be identified with certainty in the 

 field. Has a loud wailing cry, and is very bold and demonstrative 

 at nest. (F.C.R.J.) 



Bbeeding-habits. — Less sociable in breeding -habits than Great 

 and Arctic Skuas. Nest. — A rounded hollow in mossy tundra. 

 Eggs. — Normally 2, rarely 1 or 3, smaller and more elongated than 

 those of Arctic Skua : greenish to olive-brown in ground (rarely 

 pale blue) with a few dark brown spots or scrolls, chiefly at big end. 

 Average of 73 eggs, 55.43x38.48. Max. : 65.7x39.1 and 62.4 X 

 42.4. Min. : 49x37 and 49.3x33 mm. Breeding -season. — Gener- 

 ally from latter part June onward, but occasionally in early June. 

 Incubation. — Probably by both sexes ; male has been shot from 

 eggs. Period 23 days (Manniche). Single brooded. 



Food. — Occasionally pursues Gulls and Terns, but less frequently 

 than other Skuas. Feeds largely on lemmings on breeding grounds : 

 also recorded as taking field-mice, small birds, small fish {Coitus 

 gobio, Esox lucius, Gobio fiuviatilis), earthworms, insects, including 

 coleoptera and larvae, diptera, ephemeridse, and orthoptera (Forfi- 

 cula), crustacea, eggs of ducks and other birds, carrion and some 

 vegetable matter (leaves of Arctic willow and heather tips), while 

 berries of Empetrum nigrum are largely eaten by young. 



Distbibution. — British Isles. — Irregular autumn -migrant (Sept.- 

 Oct.), occasional spring and summer. Most frequent (but decidedly 

 .scarce) east coast England, usually small numbers, occasionally 

 many, as in 1879, rare south and west coasts (except 1891) and rare 

 Scotland and Ireland. Occasionally inland. 



Distbibution. — Abroad. — Breeds north Scandinavia, north Russia, 

 Siberian tundras, once recorded Jan Mayen. In America, Greenland, 

 Kotzebue Sound, Ellesmere Land, Grinnell Land, Lower Mackenzie 

 River, Discovery Bay, and doubtless many other places. In winter 

 south to Mediterranean, Japan, Florida, and 20° north latitude on 

 west coast of America. 



Obdeb ALC^. 



Seabirds (expert divers) with very short inner secondaries 

 and axillaries, short rounded or wedge-shaped tails of 12 to 

 18 rectrices. Primaries 10, secondaries 15 to 19. Bills schizogna- 

 thous and schizorhine, strong and short, not longer than about 



