SEA-BIRD MOVEMENTS I5I 



(small) overland passage to the Mediterranean, or are merely casual, 

 is not yet clear. In the Atlantic the species reaches the Sargasso Sea 

 (Jespersen, 1930), has been seen in mid-ocean between the Amazons 

 and Cape Verde, and has once only (as far as we can discover) been 

 seen off tropical West Africa — four together near the Cape Verde 

 Islands on 8 May 1947 (Bierman and Voous, 1950). The only observa- 

 tions of this species in the southern hemisphere derive from Murphy 

 (1936), who records long-tailed skuas off Peru, Chile and Argentina 

 between October and December, and Wetmore (1926) who found them 

 harrying Trudeau's terns, Sterna trudeauiy off the Buenos Aires coast 

 of Argentina in December. We can find no record whatever of this 

 species from the Indian Ocean, Australasia, or the West Pacific south 

 of Japan; on the east Pacific shore long-tailed skuas — perhaps on their 

 way to Chile — pass along the coasts of British Columbia, the western 

 United States, and Mexico. But the winter quarters of this interesting 

 species remain generally mysterious. It is possible that the long-tailed 

 skuas scatter more widely than the others, and do not usually gather 

 in numbers over special waters. 



We cannot leave the subject of sea-bird movements without a 

 glance at what are perhaps the most interesting and specialised to 

 all the secondary sea-birds — the phalaropes, the only waders that 

 spend part of their lives as true sea-birds. 



There are actually three kinds of phalaropes, but Wilson's phal- 

 arope, Steganopus tricolor, is never a bird of the open sea. The others, 

 which are both known in Britain, winter in the wide ocean, where 

 they hunt and swim for surface-plankton; an adaptation which 

 continues to astonish those who meet them under such circum- 

 stances. The larger of the two, the grey phalarope, Phalaropus fulicarius 

 (known in North America as the red phalarope) is a pan-arctic breeder 

 which has been recorded as nesting at the highest possible latitudes 

 all round the mainland and islands of the Polar Basin; in fact it has 

 been found breeding in all those lands nearest the Pole save Svernaya 

 Zemlya off Siberia and the islands north and west of Melville Island 

 in the Canadian Arctic; and might be found on these if they 

 were well explored. The southern boundaries of its breeding-distribu- 

 tion do not extend far beyond the coastal tundras of Greenland, the 

 Canadian North- West, Yukon, Alaska and Asiatic Siberia; it is not 

 found breeding in Alaska far south of the mouth of the Yukon, or in 

 Hudson's Bay (except on its north-western shore), or in Labrador, 

 or on the European arctic mainland; indeed in Siberia-in-Europe 



