Other piratical plunderers are the skuas and some other members of the gull family. With the former the practice is more habitual, or, rather, it is pursued more to the exclusion of other habits of feeding. In the more northern parts of the British Isles—especially in the Orkneys and Shetlands—the lesser or arctic skua may be seen all day long during the breeding season, taking toll of the various sea-fowl, as they fly with fish to feed their young. One might think that when once the fish had been swallowed there would be an end of the annoyance, and that the rightful owner must, by the very nature of things, now be safe. Such, however, is by no means the case. Most birds have no difficulty in bringing up again what they have swallowed down.[1] The skua, when it swoops upon a gull, does so with the deliberate intention of forcing it to disgorge the fish it has swallowed, which it then, like the eagle, catches in the air before it has touched the sea. Should it not succeed in doing this, the fisherman asserts that it will not touch it, but invariably leaves it lying on the water, or on the land, should it chance to fall there. I have myself seen skuas act in this manner, but am not so satisfied that it is their invariable practice. Terns, should there happen to be a colony in the neighbourhood, are particularly persecuted by these skuas, insomuch that the gulls derive a distinct benefit from their presence. Puffins and guillemots are also pursued, and so ingrained is the habit of piracy that the skuas will sometimes, as it were, play at it, swooping at and chasing one another in the same manner and with the same wild cries as when they practise the art in earnest. Of course, under these circumstances neither bird disgorges to the other, and it is easy to see that neither expects the other to do so. Though gulls uniformly suffer at the hands of the skuas, they can be pirates too amongst each other, and in harbour or where fishing-smacks are anchored nothing is commoner than to see a bird that has seized on some offal of fish thrown overboard mobbed by a host of others, till the morsel reappears again _de profundis_.