452 THE DIVERS 



Generally speaking, it may be stated that our British-breeding birds 

 make little or no nest, but that in other districts they have occasion- 

 ally been known to build a substantial nest in shallow water of water- 

 plants and sedges, just as the great northern-diver does under similar 

 conditions. Graf Zedlitz seems to be under the impression that no 

 nest is ever made by this species, but a glance at the photograph 

 reproduced in Mr. A. Chapman's Wild Norway (p. 109) will show that 

 there are occasional exceptions to the rule. Like the other Divers, it 

 approaches and leaves the nest on its breast, and so makes a broad 

 smooth track, which rises gradually from the water. Chapman 

 describes how a bird flushed from a nest with two eggs on the point 

 of hatching collapsed after flying thirty yards and fell heavily on the 

 water, apparently with a broken wing. For several seconds she lay 

 flapping helplessly on her side, swimming round as though paralysed, 

 in narrow circles. Half an hour afterwards the same bird was seen 

 with its mate flying fast and strong, a hundred yards high. 1 While 

 incubation is going on, the bird which is not brooding swims about and 

 feeds a hundred yards or more away, and on the approach of an 

 intruder is soon joined by the sitting bird, which cautiously leaves the 

 nest and proceeds under water to join its mate. Although the normal 

 clutch consists of two eggs, it is unusual for more than one young bird 

 to be reared, and one egg is frequently infertile. The young, protected 

 by their thick coat of blackish down, take to the water at an early 

 age, and may be seen following their parents, and occasionally even 

 scrambling on to their backs like young Grebes. A remarkable 

 characteristic which has occasionally been noticed in the breeding 

 season is the extreme boldness displayed by some birds. H. J. 

 Pearson relates how in Russian Lapland a blackthroated-diver which 

 had been put off the bank of a lake, turned round and shook its wings 

 in defiance, and adds that it will sometimes come almost up to land 

 as if about to attack the intruder, when it has incubated eggs. 2 In 



1 A. Chapman, Wild Norway, p. 110. 



2 Three Summers among the Birds of Russian Lapland, p. 161. 



