252 THE BIRDS OF THE NORTH ATLANTIC 



North Cape to Spain, and eastwards into Siberia. Large numbers of these birds 

 frequent the shores of the North Sea and Baltic, while many resort to the Black 

 Sea and Caspian. In winter they journey as far south as Portuguese East Africa 

 and Senegambia, but this migration is undertaken only by a section of the species, 

 as in Iceland oyster-catchers migrate in winter only from the north to the south of 

 the island, where the influence of the Gulf Stream renders the climate sufficiently 

 warm for them to exist at that season. Unlike most shore-birds, oyster-catchers 

 do not take to the water solely in cases of necessity, but will enter it occasional^' 

 at all times. They swim well, and escape from danger by diving. Their gait is 

 a brisk walk, with many hops, but it may become a quick, although frequently 

 interrupted, run ; the flight is low and duck-like. 



Oyster-catchers are generally found in small parties and are singularly watch- 

 ful and courageous birds. They will attack crows, gulls, and birds-of-prey with 

 such loud cries and impetuosity that they generally succeed in driving them away, 

 and their nesting-grounds are consequently but seldom invaded. The nest, which 

 is never far from water, consists of a shallow hole scratched by the bird in the 

 shingle, and lined with pebbles and broken shells. Several of such nests are 

 generally made, in one of which (not necessarily the last) are laid the stone- 

 coloured eggs, indistinguishable at a short distance from the pebbles with which 

 they are surrounded. 



Among the duck tribe mention may be made of the sheldrake 

 (Tadorna comuta), which ranges from Britain to Japan as a breed- 

 ing species, and migrates in winter to the Mediterranean, India, and South China. 

 Although essentially a shore-bird, the shelduck generally makes its nest in a 

 rabbit-burrow or some other hole some distance away from the beach. When a 

 convenient hole cannot be found ready to hand, the bird will make one for itself, 

 and in the Isle of Sylt shelducks are induced to lay in holes made by the natives 

 with the object of collecting the eggs. By taking these judiciously, as many as 

 thirty may be obtained from a single hole, although the normal number is about 

 ten. Of the hosts of other kinds of ducks which visit the coasts of the North 

 Atlantic in winter, to return to the Arctic breeding-grounds in spring, mention 

 here is unnecessary. 



Nearly all the terns are sea-birds, but the little tern (Sterna 

 Little Tern. . . ... 



minuta) often frequents inland waters, although its nest is generally 



situated near the shore. When looking for food, this tern seldom comes nearer the 

 surface than 10 feet, and often flies three times as high, nevertheless it discovers 

 quite small creatures from that height, and generally flutters some time above 

 them before dashing down into the water, to rise again as rapidly with its prey. 

 These lively birds, which scream as they chase one another in the air, are dis- 

 tinguished from other terns by their brisk movements and diminutive size. About 

 9i inches long, they have a black crown, a white tail, a yellow beak, and orange 

 legs. As breeding-birds, they range from 60° N. latitude down to the Mediterranean, 

 the Black Sea, and the Caspian, and as migrants reach Cape Colony and Java. The 

 eggs are usually laid on the sand or among the shingle, with no perceptible attempt 

 at a nest; but on the east coast of Scotland there is frequently a hollow sur- 

 rounded — not lined — with a ring of brijjhtlv coloured fragments of shells. 



