STERCORARIin/1^.. 



691 



THE ARCTIC or RICHARDSON'S SKUA. 

 Stercorarius crepidatus (J. F. Gmelin). 



The second English name is strictly applicable to a dark form of 

 this bird ; but it is often employed and has the merit of being dis- 

 tinctive, whereas the first has occasionally been conferred on the 

 next species. The Arctic Skua breeds on most of the Shetlands, 

 and has several colonies in the Orkneys, while on the mainland it 

 may still be found in Sutherland and Caithness; it also nests at a 

 few spots in the Outer Hebrides, and sparingly on two or three of 

 the Inner islands. It is a regular migrant along both sides of 

 Scotland, as well as down the east coast of England ; but it is 

 less frequent in the Channel, while comparatively irregular in the 

 western sea. To Ireland it is a periodical visitor. It has been 

 met with on inland waters in various parts of the British Islands. 



There are two very distinct varieties of the Arctic Skua, the one 



3 H 2 



