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, respectively, 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 employed, thus leaving no room for the other. Moreover, 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-
