WATCHING GULLS AND SKUAS 115 



robber. For myself, I believe that the skuas always, 

 or almost always, feed in this way, because I think 

 that when, in the satisfaction of such a daily and 

 almost constant want as hunger, some curious and 

 bizarre method had been adopted it would tend to 

 become habitual, to the exclusion of all others. Two 

 such different plans of obtaining fish as are, respec- 

 tively, swooping upon them whilst swimming in the 

 water, and catching them in the air upon their being 

 disgorged by another bird, after a chase which is 

 often long and arduous, could hardly be carried on 

 by the same bird ; for it is probable that either one, 

 to be successful, would have to be habitually em- 

 ployed, thus leaving no room for the other. More- 

 over, the adoption of such a peculiar method of 

 obtaining food at all implies a great advantage over 

 the older method, and this being the case it would 

 tend entirely to supersede it. But that the Arctic 

 skua, at any rate, thus habitually chases and robs 

 gulls one can easily satisfy oneself, nor have I ever 

 seen either it or the great skua stooping on fish, 

 like terns, gulls, or gannets. 



The young of the great skua are fed entirely on 

 herrings, which are first swallowed by the parent 

 bird, and then disgorged on to the ground in the 

 neighbourhood of the nest. I cannot say that I 

 have myself seen this done, for it is impossible to 

 watch the nesting habits of a bird that always attacks 

 you when you approach its nest, and continues to 

 do so as long as you stay anywhere near it. In these 

 grey desolate islands there is no sort of cover, no 

 tree or bush with the branches of which one can 

 make oneself a shelter, and watch unobserved. More- 



