122 BIRDS OF ICELAND 



forms, but I am inclined to attribute many of these to 

 immaturity — as the young birds are all dusky to begin 

 with, and I have only once met with a decided inter- 

 mediate form amongst old birds in Iceland in the 

 summer. In all adults the two central tail-feathers 

 are about three inches longer than the rest of the tail, 

 and are narrowed to a blunt point, but are not twisted 

 vertically, like those of the Pomatorhine Skua. Length 

 20 inches, wing 13 to 13J inches. Young birds are of 

 a pale brown, with darker streaks and bars, and rusty 

 tips to the feathers of the upper parts ; central tail- 

 feathers not perceptibly elongated. 



The Arctic, or Richardson's Skua (all the Skuas are 

 ' Arctic ') is very bold at its nest, and stoops repeatedly 

 at the head of an intruder in a rather threatening 

 manner, but never actually strikes except with its 

 wings. It gains a rather disreputable living on the 

 proceeds of others' industry. Seeing a Gull or Tern 

 wending homewards from the fishing with the appear- 

 ance of a comfortably filled crop, this bird attacks it 

 with great apparent ferocity, stooping at it like a 

 Hawk, but apparently only striking with its wings, 

 as above, until the persecuted bird tries to lighten 

 itself by ejecting the fish in its crop ; this the Skua, 

 by a quick turn, catches, usually before it reaches the 

 water. All the Skuas have this moss-trooper dis- 

 position, but it is oftenest observed in this, the 

 commonest species. Inland, in the breeding season, 

 they rob other birds of their eggs or young (especially, 

 in Iceland, the Golden Plover and Whimbrel), one 



