A' BIRD L. OVER'S YEAR 



tunnels go inwards for a long way, and at 

 the end is found a loose nest of dry grass 

 and straws and feathers upon which the 

 eggs are placed. Sand-martins breed in 

 colonies, returning season after season to 

 the same cliffs, which become riddled with 

 their holes. 



Kingfishers are also tunnel-nesters, either 

 appropriating any stray deserted burrows, 

 or else excavating holes for their own use. 

 The rock dove is a cave haunting bird, and 

 colonies of these birds breed in the caves 

 on the west coast of Scotland. 



Turning to the green woodpecker, one 

 finds a nesting hole most carefully bored 

 into the heart of various trees. The wood- 

 pecker's bill is a most powerful and efficient 

 tool and both sexes assist at the work. 

 The eggs when laid, are placed on the 

 powdered wood and chips at the bottom of 

 the hole. The titmice are also fond of 

 hiding their nests in rotten stumps of trees, 

 whilst nut-hatches too, will gladly avail 

 themselves of these opportunities whenever 

 they occur. 



Of the platform-built nests, there is, as 



well as the rook's, the wood-pigeon's, a 



D 49 



