KITTIWAKE GULL, Larus tridactylus. 



Common resideut ou our rocky coasts. Circumpolar species^ breeding 

 in the Arctic and Subarctic Regions, rarely wandering southwards as far 

 as the Tropics in winter. 



IVORY GULL. Larus eburneus. 



Rare winter visitor ; thirty to forty British records. Circumpolar 

 species, breeding in the extreme Arctic Regions of both hemispheres. 

 Straggles irregularly southwards in winter into the temperate regions. 



GREAT SKUA. Stercorarius catarrhactes. 



Rare winter visitor, breeding on the Shetland Islands. North Atlantic 

 species, breeding also on the Faroes, Iceland, and probably on some of the 

 subarctic American islands. Is not known to wander as far south as the 

 Tropics iu winter. 



POMARINE SKUA. Stercorarius pomarinus. 



Irregular winter visitor. Circumpolar species, breeding in the extreme 

 north, and wandering southwards iu winter, sometimes as far as the 

 Tropics. 



RICHARDSON'S SKUA. Stercorarius richardsoni. 



Frequent winter visitor, breeding in the north of Scotland. Circum- 

 polar species, breeding in the Arctic and Subarctic Regions. Winter range 

 extending across the temperate regions to the Tropics. 



BUFFON'S SKUA. Stercorarius buffoni. 



Irregular winter visitor. Circumpolar species, breeding in the extreme 

 north. Winter range extending far into the temperate regions, but not as 

 far as the Tropics. 



