GREAT BLACK-BACKED GULL 



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the Atlantic ; its breeding-range in the western hemisphere extending 

 from Greenland and Labrador and the Great Lakes to Baffin Bay, and in 

 the opposite hemisphere from Iceland in the west to the Petchora valley 

 in the east, and southwards to about the 50th degree of north latitude. 

 In winter the species ranges on the one side as far south as Florida, 

 and rarely the Bermudas ; and on the other to the Canaries and the 

 coasts of the Mediterranean, as far east, although rarely, as Egypt, 

 while it also visits inland waters. Although only a few isolated 

 nesting - sites are known on the southern and western coasts of 



MOUNTED IN THE ROWLAND ' 



I STUDIOS 



GREAT BLACK-BACKED GULL. 



England, as we pass north the great black -back is found breeding 

 abundantly in the British Islands, more especially in Scotland. In 

 Ireland it breeds in small numbers all round the coasts, but is more 

 common on the west side than elsewhere. 



An interesting question has been raised as to which species of 

 black-back nests on the grassy slopes crowning the Bass Rock. The 

 ornithologists who visited the Bass Rock in the first half of the 

 last century appear to have referred all the members of the small 

 colony of those gulls which annually breed there to great black- backs, 

 but all those which have been observed of late years have proved to be 

 lesser black-backs. The breeding of the latter species on the Bass was, 

 in fact, proved some forty years ago. The question thus raised is 



