I^ SEA-BIRDS 



in July — the true High Arctic. In Newfoundland we reach the limit 

 for breeding gannets, ring-billed gulls and common terns, and perhaps 

 also Caspian terns. The Leach's petrels breed as far as Newfoundland 

 Labrador, but no farther, and it is doubtful whether the double- 

 crested cormorant now breeds as far. South-west Greenland is less 

 'arctic' than opposite parts of the Canadian Arctic Archipelago at the 

 same latitude; and it is not surprising that some species extend beyond 

 Labrador to West Greenland, though not to Baffin Island and the 

 other Canadian islands. Such species are the razorbill and common 

 guillemot, the latter having only one small colony in West Greenland. 

 The European cormorant extends to West Greenland and previously 

 had a small outpost in Baffin Island, from which it has now disappeared, 

 and it is also extinct in Newfoundland Labrador, after much human 

 persecution. The puffin does not breed in the Canadian Arctic but 

 goes far north in Greenland where it is of a distinctive, large arctic race. 



Species which extend in breeding-range all the way from Newfound- 

 land to Arctic Greenland and Canada are the herring-gull, great black- 

 back, kittiwake, arctic tern and black guillemot. All these except 

 the blackback reach the High Arctic, if we regard the Iceland gull 

 Lams argentatus glaucoides, as a herring- gull, as we think we should. 



The glaucous gull Larus hyperboreus, does not now breed in New- 

 foundland, but nests commonly from Newfoundland Labrador all 

 the way to the High Arctic, as does the arctic skua Stercorarius para- 

 siticus; two other skuas, the pomarine S. pomarinus, and the long- 

 tailed skua S. longicaudus, do not breed in Labrador, but farther north 

 in both Canadian and Greenland Arctic. On the west side of the 

 Atlantic-Arctic the fulmar Fulmarus glacialis, breeds no farther south 

 than Greenland and Baffin Island, although it nests south to about 

 latitude 50° north on the east side of the Atlantic. 



This leaves the three High Arctic sea-birds of the West Atlantic 

 for consideration — the little auk Plautus alle^ Sabine's gull Xema sabini, 

 and the ivory-gull Pagophila eburnea. All three breed in the more 

 northerly parts of the Canadian Arctic Archipelago and Greenland, 

 though the first may not have more than one colony west of Baffin's 

 Bay. Sabine's gull is a rare bird that often nests in arctic tern colonies. 

 The ivory-gull is the most northerly bird in the world in the sense 

 that it breeds nowhere south of the Arctic Circle, but as far north as 

 the land goes. The extraordinary, rare, Ross's or rosy gull Rhodostethia 

 rosea, which normally nests in the aldergroves of some north-flowing 

 rivers of eastern Siberia, has once bred in Greenland. 



