Sept., 1 9 19. The Irish Naturalist. 97 



RELATION OF SONG TO THE NESTING OF BIRDS. 



BY J. P. BURKITT. 



My discovery, if I may dignify it by that name (see Irish 

 Nat., November, 1918), that a huge number of Greater 

 Whitethroat males may get no mates till the end of June, 

 if at all, and that this explains the abundance and prolonga- 

 tion of their song, which would otherwise have practically 

 ceased shortly after mating, led me to consider to what 

 extent the same might apply to other songsters. In other 

 words, in what species is the song an indication of a mateless 

 male, and in case it is not, can any relation be established 

 between the song and the connubial state, so that the song 

 can be taken as an indication thereof ? Such knowledge 

 might possibly be a stepping-stone to interesting results. 

 I thought there would be little trouble in getting informa- 

 tion on this point from books, but so far I have got none. 

 Mr. H. F. Witherby advised me to get Howard's " British 

 Warblers : a History with Problems of their Lives." But as 

 long as the price is £8, as quoted to me, I shall be unfor- 

 tunately ignorant of its contents. It is not in the National 

 Library, Dublin. Mr. Witherby also kindly referred me to 

 two articles by Messrs Alexander in British Birds (vol. i., 

 p. 367, and vol. iv., p. 224^). I was able to procure the latter, 

 and Mr. H. G. Alexander has kindly sent me a copy of the 

 former. These articles give a summary of several years' 

 observation of the song period of a large number of birds ; 

 that is, of the months in which they sing, and the effect of 

 weather influences. These notes are most valuable and 

 interesting. It is a pity they are not more readily available. 

 Their subject is related to that of my question, but they 

 give no direct information on it. The answer which I seek 

 may in respect of many of the common songsters be well 

 known to individuals, but not treated collectively any- 

 where. Schoolboys might turn some of their keenness on 

 this instead of mere collecting. In very abundant species, 

 it would need the selection of sufficiently isolated pairs. 



I made this year a considerable effort to find for myself 

 the answer in the case of Chiffchaff, Willow- Wren, and Sedge 

 Warbler. I already have an approximate knowledge in 



