BLACK TERN. 249 



Sweden, and the Baltic. It is found throughout a great part 

 of Europe and western Asia, and in winter visits tropical 

 Africa. Knowledge of the British distribution of this, and 

 many other passage birds, depends largely upon scattered 

 notes of observers who cannot regularly watch one spot ; 

 consequently it is counted rare and irregular in the west and 

 inland. In Wales, Lancashire, Cheshire, and various scattered 

 inland waters, closer attention proves it to be far more frequent 

 than most authorities affirm ; indeed, on the Cheshire meres it 

 is a regular visitor in spring and autumn, often appearing in 

 little parties. North of Cheshire in the west, and south 

 Yorkshire in the east, and in Ireland, it is less frequent, though 

 it has been noted in Orkney and the Outer Hebrides. 



Though drainage destroyed some of its former nesting haunts, 

 there remain many wild marshes where it could be secure. 

 Collectors in this case have been unjustly blamed for its 

 departure, nor is it probable that it w^as badly harried for its 

 flesh or plumage ; the desertion of the haunts seems to have 

 been deliberate, an intentional restriction or change of habitat, 

 possibly due to the increase of population and consequent more 

 frequent disturbance on the marshes. The last recorded Norfolk 

 nest was in 1858. 



In summer plumage the Black Tern is a very dark bird, its 

 slate wings, back, and tail look almost pale compared with the 

 deep blue-black of its head, neck, and breast. From both 

 White-winged and Whiskered Terns, its nearest allies, it may 

 be told by its black bill and blackish legs, red in these birds. 

 From the former, when both are mature, its darker wings and 

 grey tail and tail-coverts are distinct when in flight, and the 

 latter is a larger, paler tern with a black cap and not wholly 

 dark head. The immature plumages are more puzzling. The 

 Black Tern does not hurry through England, but stays for a 

 few hours, and often days, about some inland water where food 

 is abundant. It beats up and down with desultory flight, swooping 



