254 



A VES ORDER COL YMBIFORMES. 



The downy nestlings are striped, and in the first plumage the dabchicks are 

 brown above. In the autumn they are to a certain extent migratory, and are 

 shot in our tidal harbours ; but in mild winters they do not desert their native 

 homes. In summer, both sexes don a nuptial plumage, with a yellow patch 

 on the bill and a black breast, against which the rufous colour of the face and 

 neck forms a striking contrast. In all the 

 grebes, the brighter colours and the ornamental 

 tippets and crests are dropped during the winter 

 season. 



The divers are birds of the Northern Hemi- 

 sphere, few in number and arctic in habitat. 

 Four species are known, all of 

 The Divers. which are found in Great Bri- 

 Order tain, two of them nesting within 



Colymbiformes. our limits. The red -throated 

 diver (Colymbus septentrional is) 

 is one of them, and the black-throated diver (C. 

 arcticus) is the second. The great northern 

 diver (C. glacialis) is a more or less frequent 

 visitor in winter, and the white-billed diver 

 (C. adamsi) has occurred a few times. 



This is chiefly known as an inhabitant of 

 North America and Iceland, as the great north- 

 ern diver which breeds in the 

 Old World will probably be 

 found to be C. adamsi. The 



habits of all the divers are much the same. On the water 

 they are at home, swimming about and diving with the great- 

 est of ease ; but on land they are very awkward, and the 

 backward position of their legs seems to make it impossible for the birds 

 ever to stand upright. In fact, they seem to shuffle along the ground with a 



The Great 

 Northern Diver 



(Colymbus 

 glacialis) . 



Fig. 19. THE LITTLE GKEBE OR 



DABCHICK 

 (Tachylaptes Jluviatilis). 



snake-like motion, and never walk. They excel all the grebes in their power 



of flight, though, as a rule, they trust 

 to their swimming and diving powers 

 to escape from danger, and are often 

 to be seen swimming in the sea far 

 away from land ; and they are also able 

 to submerge their bodies, so that only 

 the head and neck is exposed, and 

 they can remain under water for an 

 astonishing time, the great northern 

 diver having been known to remain 

 below the surface for eight minutes. 

 The nesting-place is on some inland loch 

 or secluded lake, and the nest is a 

 poorly constructed affair. The eggs are 

 two in number, of a russet-brown or olive-brown colour, with black spots and 

 fainter block underlying markings. 



The divers differ from the grebes in having webbed feet and a well-developed 

 tail. The young birds are covered with down, and are able to dive and shift 

 for themselves shortly after they are hatched. The sexes are alike in plum- 

 age, and they have a distinct summer and winter dress, as with the grebes. 



Fig. 20. THE GREAT NORTHERN DIVER 

 (Colymbus glacialis). 



