The Skua, Labbe, or Dung-bird (_Stercoraria_, Vieillot), Fig. 111, is remarkable for its stout bill, which is nearly cylindrical, and covered with a membrane from the base as far as the nostrils; the upper mandible is convex, hooked, and armed at the extremity with a crooked point, which almost appears as if it was supplementary. These birds principally frequent the sea-shore, but at the time of storms they venture further inland. They fly very rapidly, even against the strongest wind. They pursue the Sea Mews and the Terns most inveterately, and sometimes even Boobies and Cormorants, their only aim being to deprive these birds of the prey they have caught; for the Sea Mews and the Terns are their purveyors. Incessantly do they pursue, harass, and beat these species until they have forced them to disgorge and drop their booty: before the fish falls into the sea it is caught by the active persecutors. This singular habit has given rise to the belief that Skuas feed upon the excrement of the Sea Mew, and to this they owe their name of Dung-birds. In some countries, as the Shetland Islands, these birds are held in veneration. The care and protection of the sheep are almost entirely intrusted to them, owing to their possessing an inveterate hatred against Eagles; for as soon as the monarch of the air appears in view, three or four of them combine together to give him battle. They never attack him in front, but harass him pitilessly until his strength is so reduced that they can completely conquer him, or at least force him to retreat. In recompense for these services, the inhabitants are in the habit of throwing to the Skuas the refuse of their fisheries. These birds almost always live in solitude, so that they may be more readily able to procure their food, which consists of fish, mollusks, eggs, young sea-birds, and small mammals. They inhabit the Arctic regions of Europe and America, and make their nests in the heather; they lay from two to four eggs, which are sat upon by the male and female birds alternately. They are courageous enough to defend their young brood against any kind of animal, and even against man. There are four European species: the Parasite Skua (_Lestris parasiticus_), which inhabits Greenland, Newfoundland, and Spitzbergen, and visits tolerably often our Atlantic coasts; Richardson's Skua (_Lestris Richardsonii_), which is very plentiful in Sweden, Norway, Lapland, and North America; the Pomerine Skua (_Lestris pomarinus_), which is very common in Newfoundland, Iceland, and the Feroë Islands; the Common Skua (_Lestris cataractes_), commonly called the Brown Stoëland.