How Animals Work. 



nevertheless does a certain amount of harm to growing 

 timber, and therefore is not always looked upon with 

 much friendliness by the forester. Besides the Yaffle, 

 we have in our English woodlands two equally expert 

 bird carpenters namely, the Great Spotted or Pied 

 Woodpecker and the Lesser Spotted Woodpecker, both 

 smaller than the Yaffle, and excavating similar though 

 smaller nesting holes in the branches of the trees. The 

 Great Spotted Woodpecker in the spring-time often 

 attracts attention by a remarkable drumming sound, 

 almost like the roll of a kettledrum, which it produces 

 with its bill on some dead branch of a tree. This 

 peculiar drumming performance probably is not for 

 the purpose of scaring insects out of the crevices in 

 the branch by its vibration, but rather is a form of 

 display on the part of the male to attract the attention 

 of the hen bird. 



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