The Great Black-Backed Gull. 9* 



—but for the white tips of many of the quills, of the scapulars and of the secondaries, 

 where they form a prominent alar bar — are black (varying to slate-blue) in striking 

 contrast to the rest of its plumage ; " the uttermost primary white for nearly 

 three inches, its upper part blackish ; the second similar with a black spot or a 

 narrow subterminal bar according to age on the inner web ; third quill with an 



indication of white on the shaft blackish above, next the shaft, with a 



fairly visible greyish wedge ending in white on the inner web ; fourth and fifth 

 quills with more defined grey wedges on the inner webs, and a black sub-apical 

 bar ; remaining quills slate-grey, except the tips " ; a circle round the eye scarlet ; 

 iris pale yellow ; bill yellow, its angle yellowish-red ; legs and feet bluish-white ; 

 length of the male 29 inches ; wing 20 ; tarsus 3 ; middle toe and claw 3. 



The Great Black-backed Gull mates early in April and, by the beginning of 

 May, the couple have fixed on a site and arranged their home. This may be placed 

 near the shore ; sometimes among bare stones ; on a high steep hill side ; on open 

 moors ; on an island in a fresh water loch ; or on the top of a " stack " or in- 

 accessible cliff; but rarely on the ledge of a precipice. It is gregarious, but less 

 so than many other species. Harvie- Brown and Buckley describe, in their " Inner 

 Hebrides," " one colony known to us [where] there are about fifty pairs . . . and 

 on another island perhaps even a more extensive colony mixing with, or keeping 

 slightly apart from, the Herring and Lesser Black-backed species." The nest is 

 not, as a rule, a very elaborate structure; and it differs in the materials of which 

 it is built with the site. If near the sea, it may be of loose grass, seaweed, or any 

 vegetable material the locality provides ; if inland, of grasses or plants and a few 

 feathers. Herein are deposited two or three eggs, the latter being the more usual 

 number. They are far more regular in colour than those of the last described 

 species. They are covered with small irregular spots, sometimes blotches, but 

 occasionally scrolls upon a greyish-brown ground. In size they run to about 31- 

 inches in length by 2i in diameter. 



In the beginning of June young chicks may be found in the nurseries as 

 charming little balls of down, of a pale brown greyish-white, or sandy colour, spotted 

 with black on the head, neck aud back, elsewhere speckled with grey ; underneath 

 greyish white and with few, or no spots ; bill brownish-black at the base, pale 

 horn anteriorly, light at the tip ; legs and feet livid flesh colour. They are able to 

 run the moment they are hatched almost, and they will take to the water when a few 

 days old. Mr. Pearson saw a nestling swim down a rough river to an island a 

 mile lower. They take from five to six years to attain their fully adult plumage. 

 When fledged the head and neck are greyish- white, streaked with greyish-brown ; 

 the upper side streaked or mottled with blackish-brown and greyish-brown ; tail 



