The Pomatorhine Skua 



flanks and abdomen, which are brown. Length 21 in. ; 

 wing 14' 2 5 in. 



The young bird in its first autumn is brown mottled 

 and barred with dull rufous. It takes more than a year 

 to assume the full adult plumage. 



THE ARCTIC OR RICHARDSON'S 



SKUA 



Stercorarius crepidatus (J. P. Clmelin) 



This is the commonest of the Skuas, occurring on all 

 the Scottish coasts and being fairly common in the east 

 of England every autumn. In Ireland and the west of 

 England it is only an irregular straggler. 



It breeds in the Shetlands, Orkneys, and the north of 

 Scotland, some moor at no great distance from the sea 

 being chosen as a summer home. No nest is made, but a 

 depression is formed in the moss or grass on which the 

 two brownish green eggs, blotched with darker brown, are 

 laid. The young when first hatched are covered with dark 

 brown down. ' 



In its habits and food it does not differ from the other 

 Skuas. 



This species is dimorphic, one form having light under 

 parts, and the other being of a uniform sooty brown all over. 

 The light-coloured birds predominate in the north of their 

 breeding area and the dark ones in the south, but when 

 they meet they breed indiscriminately, and intermediates 



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