132 



SEA-BIRDS 



9« 8° 7° i>' 5* 4" 3° 2° 1° o' 



100 KM 12 



11 



4 5 



100KM 



10 



12 



7 



lAT. 



6o- 



sr 



V' 



56° 



iS' 



Fig. 20 

 A famous little auk wreck in Scotland, that of 1894-95 replotted from 



W. E. Clarke (1895): 



#: one; ■ : several; *: Tnany 



faced boobies of the tropics, though these last two occasionally work a 

 little farther afield. 



\Vynne-Edward's offshore birds include the gannet, all the auks 

 except the little auk, and two Lams guUs^ the lesser blackback and the 

 herring-gull. We would suggest that the black guillemot is perhaps 

 more coastal and that the puffin is somewhere between an offshore and 

 a pelagic species. Offshore birds, by definition, are those which obtain 

 their food within the continental shelf which, in the Atlantic, is, 

 generally speaking, marked by the lOO-fathom line and is at most 

 200 miles from land. Of course, birds do not know where the 100- 

 fathom line is, but it coincides practically with the edge of human 

 fishing-grounds and the food changes very quickly beyond this point. 



