CHESTNUT-SIDED WARBLER 375 



nor are they so pleasing as those of other musical warblers of this 

 genus. 



"The territory song consists of 4 to 9 notes on a medium pitch, usually 

 rhytlrmic and of even length, followed by a louder, high-pitched, 

 strongly accented note, and then by a lower terminal note. This is 

 the song commonly translated as very^ very, pleased to meetcha. In 

 all but 3 of 30 records of this song the beginning notes are 4, 5, or 6 

 in number. In 20 records the first notes are single notes, and in the 

 other 10 they are 2-note phrases. This song is always rather short, 

 varying from 1% to 1% seconds. 



"The nesting song is so variable that it is difficult to say about it 

 much that is definite. Some notes, near the end of the song, are usually 

 high-pitched and strongly accented, but there are numerous exceptions 

 to this. Of 41 records, 19 are composed wholly or mainly of slurred 

 notes, while 21 are single notes or 2-note phrases in a loud, rapid 

 chatter. In the slurred songs the notes are run together. In some 

 records the notes are continuous throughout, without a pause. In the 

 non-slurred songs the notes are distinctly separate. The nesting song 

 is somewhat longer than the territory song, varying from 1% to 2^^ 

 seconds. 



"The pitch of both songs is about the same, varying from E'" to 

 A'"', a range of two and a half tones more than an octave but about 

 an octave lower than that of such species as the blackpoU and the 

 Blackburnian. The song is to be heard from the arrival of the bird 

 in migration till the midle of July. The average date of the last song 

 in Allegany State Park, in 14 years of observation, is July 17. The 

 earliest is July 12, 1931, and the latest July 24, 1927." 



Albert R. Brand (1938) gives the approximate mean number of 

 vibrations per second in the song of the chestnut-sided warbler as 

 5,125, with the highest having 8,775 and the lowest 3,100 vibrations' per 

 second. This compares with a mean of 8,900 for the black-poll 

 warbler and 8,600 for the grasshopper sparrow, or an average of 4,000 

 for passerine songs in general. Francis H. Allen tells me he once 

 found one "with a song consisting of a hurried repetition of a single 

 note as wit-wit-wit-ivit-iuit-wit-ioit-ioit. Sometimes this was followed 

 by the characteristic warble of the weaker song, and only with this 

 addition was the song recognizable as that of the chestnut-sided 

 warbler. The call note of the species is a thick chip with an L in it." 

 Miss Stanwood (MS.) writes the song as '-'■loee-wee-wee-wee-chi-tee- 

 loeeP 



It seems to me that the rhythm of the ordinary song can be well ex- 

 pressed in human words, or catch phrases ; for instance, to Sidney E. 

 Ingraham (1938) it sounded like : "/ wish, I wish, I wish to see Miss 

 Beecher! except that we should normally need three or four seconds 



