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others rich reddish-brown, usually heavily blotched with 

 darker shades of brown, or they may be finely speckled or 

 not marked at all. They resemble those of the Common 

 Tern, but are, on an average, smaller. 



Incubation seldom becomes general before the end of the 

 first week in June. As with other Terns, the males bring 

 fish to feed the females when incubating. 



In defence of its young and eggs, the Arctic Tern possesses 

 undaunted courage. 



Geographical distribution. North of the British Isles, 

 the breeding-range is circumpolar, and this species reaches 

 far within the Arctic circle. It has been obtained above 

 lat. 82 N. On migration in autumn it extends widely 

 over the European, Asiatic, and African Continents, even 

 to lat. 66 S., i.e., beyond New Zealand (Saunders). 



DESCRIPTIVE CHARACTERS. 



PLUMAGE. Adult male nuptial. This species so closely 

 resembles the Common Tern in plumage that it is only 

 necessary to point out the distinguishing features. In the 

 Arctic Tern the breast and abdomen are of a uniform 

 'french ' or 'pearl' grey, without a vinaceous tint. Chin, 

 cheeks, and throat, also grey, but paler in shade ; tail- 

 feathers, white, edged externally with very pale grey; the 

 outer feathers of the tail longer, and the grey stripe on the 

 inner web of each outer primary paler and narrower than 

 in the Common Tern. 



Adult female nuptial. Similar to the male plumage ; 

 outer tail-feathers shorter. 



Adult winter, male and female. Forehead and top of 

 head, mottled with white ; breast and abdomen, paler than 

 in the nuptial plumage. 



Immature, male and female. -- Forehead and top of 

 head, whitish ; back of head, blackish ; sides of neck, 

 washed with buff ; back of neck, back, and wings, mottled 

 and barred with buff; outer web of tail-feathers, greyish ; 

 breast and abdomen, white. 



BEAK. Coral-red. 



BEAK. (Immature Bird.) Black (cf. Common Tern). 



FEET. Dull red. 



IBIDES. Blackish-brown. 



