( 40 ) 

 NOTE ON THE DRUMMING OF WOODPECKERS. 



BY 



J. S. HUXLEY. 

 The jarring or drumming sound produced by the Greater 

 and Lesser Spotted Woodpeckers {Dry abates major and D. 

 minor) in spring is usually supposed to be produced mechani- 

 cally by the rapidly repeated impact of the beak on hard 

 wood. Mr. Warde Fowler recently showed me a letter from 

 a correspondent (Dr. J. Eddison of Leeds) who had heard 

 and seen a Greater Spotted Woodpecker drumming day after 

 day last May. It had frequently chosen the same spot for its 

 performance, a dead branch, hollow for part of the way ; 

 this branch was eventually cut away, and there was no trace 

 to be found of any mark made by the beak where the bird 

 had been hammering, though the blows struck were audible 

 for five hundred yards. This entire absence of dents had led 

 Mr. Fowler to wonder whether the sound could not be pro- 

 duced entirely by the bird's voice organ. 



This supposition is, I think, unnecessary. In the first 

 place, my own observations on Lesser Spotted Woodpeckers 

 show that they do actually touch the wood with their beaks 

 when drumming.* Further, one need not suppose that a 

 violent impact is required to produce the sound. As long 

 as rapid blows succeed each other regularly, very small force 

 will be necessary to set the wood vibrating in such a way 

 as to give out a powerful sound. It is the periodic enforce- 

 ment of vibration by fresh blows, not their intensity, that 

 will provide the right conditions. 



In this connection, some account of the habits of an 

 American species, the Red-headed Woodpecker {Melanerpes 

 erythroccphalus) , may be of interest. This species is abundant 

 in the Southern States, and drums not only on trees, but on 

 all sorts of artificial objects. While staying in Georgia one 

 spring, I was usually woke by one or more of these birds 

 performing on the tin roof of the house. The sound then 

 produced did not at all resemble that made by the bird when 

 drumming on a tree. The most conclusive evidence, however, 



* Dr. Eddison, in a second letter, is quite certain of this (W.W.F.). 



