360 BRITISH BIRDS. 



he fell, and was at once surrounded by about a hundred or a hundred and 

 fifty Buffon's Skuas, flying in all directions, generally about ten within 

 shot. This continued for about half an hour, during which Harvie-Brown 

 came up, and between us we bagged a dozen birds, one of which proved to 

 be a Richardson's Skua. They were very noisy birds, continually making 

 a cry like yak, yak, as they flew towards us. They screamed wildly as they 

 flocked together and left us; but as soon as our backs were turned we 

 saw them flying back to the same place. Buffon's Skua looks like a great 

 black Tern on the wing, often hovering in the air like a Kestrel, and in 

 other ways is very Tern-like in its habits. Six days afterwards we visited 

 the same spot ; the large flock of Buffon's Skuas had returned, some were 

 on the moor, and many were swimming on the river. 



Buffon's Skua feeds on fish, crustaceans, and mollusks, in addition to the 

 insects, fruit, lemmings, or small birds which form its principal food during 

 the breeding-season. On the ocean, this bird is as great a robber as its 

 congeners, numbers of them following the flocks of Kittiwakes, swooping 

 down upon them like Hawks, and compelling them to disgorge some of 

 their recently caught fish. 



Its nest is a slight depression in the grass or moss, lined sparingly with 

 a little dry grass. The number of eggs is almost invariably two ; but in 

 very rare instances one only, or as many as three are reported to have been 

 found. They are precisely similar in colour to those of Richardson's Skua, 

 and are subject to the same variations, but on an average they are slightly 

 smaller in size. They vary in length from 2'2 to 1*9 inch, and in breadth 

 from 1*6 to 1*4 inch. 



Macfarlane, who found it breeding in some numbers near the shores 

 of the Arctic Ocean, not far from the Mackenzie River, remarked that 

 the female sometimes feigned lameness when flushed from the nest, 

 and that both parents attacked an intruder with great boldness and 

 pertinacity. 



Buffon's Skua may easily be distinguished from the Great Skua and the 

 Pomarine Skua by its narrow pointed central tail-feathers, which exceed 

 the lateral feathers in length by four to eight inches. Compared with 

 Richardson's Skua, it is, on an average, a smaller bird with longer central 

 tail-feathers and fewer primaries with white shafts (seldom more than the 

 first and second) . In all these points the two supposed species are said 

 to intergrade ; but it is asserted that a constant character is to be found in 

 the positions of the nostrils, which in Buffon's Skua are said to be placed 

 nearer the frontal feathers than the point of the bill. 



It is not known that there is any difference in the colour of the sexes 

 of Buffon's Skua ; but females are said to have slightly shorter centre 

 tail-feathers than males. The adult Buffon's Skua very closely resembles 

 the light form of Richardson's Skua, but it is not known to have a dark 



