GREAT BLACK-BACKED GULL. 45 



they are found straying singly or in pairs about the marshy ponds 

 where they seek their future summer homes." 



"During the cruise of the Corwin, in the summer Jof 1881, the 

 writer found this fine bird at every point which he visited along the 

 coast of Behring Sea and the Arctic Ocean." 



They are among the last birds to leave the marshes, which they do 

 only when the ice shuts them out in October. 



Recently, Mr. Ridgway has sought to separate the eastern from 

 the western forms of this species, owing to a slight difference in size 

 and some other points of distinction, but it is doubtful if the change 

 will be generally accepted. 



Genus LARUS Linnaeus. 

 LARUS MARINUS (Linn.). 



17. Great Black-backed Gull. (47) 



Feet, tlesh-coloi-ed ; bill, yellow with red .spot. Mantle, blackish slate-color; 

 lirst primary, with the end white for 2-3 inches ; second primary, with a white 

 sub-apical spot, and like the remaining ones that are crossed with black, 

 having the tip white (when not quite mature, the fii'st with small white tip 

 and sub-apical spot, the second with white tip alone). In winter, head and 

 neck streaked with dusky. Young: — Whitish, variously washed, mottled and 

 patched with brown or duskj^ ; quills and tail, black, with or without white 

 tips ; bill, black. Very large ; length, 30 inches ; wing, ISA ; bill, above 2i. 



Hab. — Coast of the north Atlantic ; south in winter to Long Island. 



Nest on the ground, built of gi-asses, bulky and deeply hollowed. 



Eggs, three, bluish-white or olive-gray, irregularly spotted, an<l blotched 

 with reddish-brown and lilac. 



This species is common to both continents, breeding abundantly in 

 Norway, as far as North Cape. It is also very common in Scotland, 

 especially on the indented coasts and islands of the north and west, 

 and also on the outer Hebrides. Thei-e they often have their nests 

 on the heathery hillsides, and are seen coursing along in search of 

 wounded grouse, sickly or injured ewes, weakly lambs, eggs or carrion, 

 nothing in the way of animal food coming amiss. 



In Labrador, Mr. Abbot M. Frazer found them breeding on small 

 islands, usually placing their nests on some elevated spot. During 

 the breeding season there, they feed largely on the eggs of other birds, 

 especially on those of the murre, and on young eider ducks. 



They are seen roaming round the western end of Lake Ontario till 

 the enfl of March, when they all disappear for the season. 



