BIRDS OF PEASEMARSH 



advantages in a removable roof. Small 

 hinges at the back and a hook in front so the 

 roof will raise like a trap door, can be used, but 

 fastened thus it will not always remain per- 

 fectly tight, as high winds frequently loosen 

 hook or hinges. We have found that a plug 

 that just fits into the excavation at the top of 

 the nest box, fastened under the roof, is the 

 simplest and most satisfactory way of holding 

 the roof down. 



Flask shaped excavations are not easy to 

 make and require special machinery and much 

 labor. Fortunately the birds can be induced to 

 do the work for themselves, and their beaks are 

 the best of tools, if the wood is suitable. A sec- 

 tion of an old log, decayed in the centre, can be 

 cut in the same way, and an opening for the 

 bird's entrance started in it. It can then be 

 hung on a tree in place of a finished nest box. 

 The Flickers, if they find other requirements 

 desirable, will burrow it out to suit themselves. 

 The idea of trying this experiment came after 

 examining an old apple tree they had been 

 working on. They evidently thought, from the 

 decayed spot at the top, that the trunk was de- 

 cayed all the way down the centre, and had 

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