16 BRITAIN'S BIRDS AND THEIR NESTS. 



are circumpolar in their distribution, ranging so far 

 north that a considerable migration is necessary in autumn, 

 at which season they show a gregarious tendency. At all 

 seasons Red-throated Divers may be found off our coasts ; 

 immature birds chiefly, with spotted backs, or adults in the 

 winter plumage that lacks the red throat. But it is only 

 amid such surroundings as we have described that this 

 species breeds. Very sparingly is it found, if now at all, in 

 the north of Ireland, but more abundantly in the north 

 and north-west of Scotland, from Perthshire and Argyll- 

 shire to Orkney and Shetland, and those specially favoiu'ed 

 isles — the Outer Hebrides. 



The nest, if any, is a mere untidy heap of weeds a 

 few feet from the water's edge, and a well-marked groove 

 usually shows where the birds are accustomed to push 

 themselves up to their nests. The eggs are two in number, 

 rather elongated in shape, and rich olivaceous brown in 

 colour, with spots and blotches of umber. They are laid 

 in Scotland in May or June, and both birds take part in 

 incubation, lying rather than sitting on their eggs. In 

 due course the young are hatched, and are found to be 

 clothed in down of a sooty-brown colour, paler below. 

 They soon abandon the nest, for they are active from 

 the first, and from their earliest efforts show much of the 

 agility and skill in the water which is their birthright, for 

 it has been the saving of their archaic race. 



THE BLACK=THROATED DIVER 



(Colymbus arcticus). 



Although, as regards numbers off our coasts in winter, 

 this species does not come next to the Red-throated Diver, 

 it is the only other Loon which nests in the British 



