THE BIRD-LIFE OF LONDON 



frequent visitor to Wanstead and other suitable parts of 

 the Essex suburbs. 



That Terns of several species visit the Metropolitan 

 area during their annual migrations has long been known. 

 It is impossible to name the exact species in a great many 

 instances, observations, unless made by an expert or a 

 person familiar with the various Terns that frequent the 

 British seas during summer, being practically worthless 

 in this respect. Both the Arctic Tern (Sterna arctica) 

 and the Common Tern (Sterna hirundo), there can be no 

 doubt, occur casually within our limits not only in the 

 vicinity of the river, but elsewhere at reservoirs and other 

 large sheets of water. Their visits, however, are always 

 fleeting ones, merely incidents of the migration journey 

 the birds are engaged upon, and of transient interest 

 only to the London observer. The Sandwich Tern 

 (Sterna cantiaca), the largest of the species that visit the 

 British Islands, has also, I believe, been recorded from 

 the Metropolitan area. Lastly, allusion may be made to 

 the Black Tern (Hydrochelidon nigra), which evidently 

 passes London's environs on migration at times. It has 

 also been observed north of our limits at Tring Reservoirs, 

 from which we may reasonably presume that Kingsbury, 

 the Welsh Harp, and other lakes in that direction are 

 visited too. 



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