Ground and Underground Nests 



riddles, is a burrower. This creature, with its hair-like 

 feathers, its nostrils at the end of its long, curved beak, 

 instead of at the base as with other birds, and its 

 apparently wingless, tailless body, though not uncommon, 

 is rarely seen, for it is shy and a night bird. By day it 

 hides in its burrow, a short tunnel ending in a chamber 

 lined with fern leaves. In this chamber the hen deposits 

 her egg, which is remarkable for its size, being one quarter 

 the weight of the bird that laid it. No bird living lays a 

 larger egg for its size. The kiwi is probably possessed 

 of a keen sense of smell, for it has a habit of probing moist 

 ground with its long bill and sniffing out luscious worms 

 on which to make a meal. 



There are many burrowing birds in Britain. The sand- 

 martin is one of the best known and is, moreover, one of 

 the most expert burrowers the world over. In the 

 selection of a site for its nest the bird displays excellent 

 judgment. Soil that is easily worked is preferred to that 

 of a harder nature ; but there is one essential, the ground 

 in which the tunnels are made must be of a nature that 

 there is no fear of the walls of the excavation falling in. 

 Should suitable soft soil not be available, this little bird, 

 with the fragile beak, will not eschew sandstone. 



A convenient sandy cliff is the site usually chosen, and, 

 clinging thereto, the martin sounds the surface, by tapping 

 with its beak, till it finds the ideal spot for its purpose. 

 The little bird is a clever engineer. Clinging to the face 

 of the cliff with its feet, it works in a circle, chipping 

 pieces of soil or rock away with its beak. The actual 

 burrow is inclined slightly upwards, and in working thus 

 the bird displays its wisdom, for thereby rain is prevented 

 from reaching the nest within. For a couple of feet or 

 more the work of excavation is continued ; soil is broken 

 by the bird's beak and thrown out of the tunnel by its 

 feet. Unless the luckless little engineer should encounter 

 a rock or tree root during its labours, the work is rapidly 

 completed. Should an obstruction be encountered, either 



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