1378 U.S. NATIONAL MUSEUM BULLETIN 237 part 3 



Donald J. Borror and William W. Gunn (1965) studied songs of 711 

 white-throated sparrows, 433 of which were recorded. Most of the 

 birds were on their breeding territories from Massachusetts and New 

 Brunswick to Minnesota and British Columbia, but 59 were on migra- 

 tion in New York, North Carolina, and Ohio. Most recordings were 

 analysed with a Vibralyzer sound spectrograph ; others were studied by 

 listening to them at reduced speed. These songs were composed of 

 the following types of notes: notes lasting more than a fifth of a second 

 and relatively steady in pitch, similar notes beginning with a shorter 

 upslur (rarely, a downslur), triplets (occasionally couplets) about as 

 long as the preceding notes but more or less divided into three short 

 notes usually of about equal length, and occasionally other types 

 including short distinct notes less than a tenth of a second in duration. 

 The pitch of steady notes in the whole sample ranged from 2,150 to 

 6,500 cycles per second (cps) and from 1,500 to 6,600 cps including 

 upslurs and downslurs. Lowther and Falls recorded a bird with notes 

 ranging from 7,000 to 10,000 cps but this bird also gave unusually 

 high-pitched calls and was doubtless abnormal. Borror and Gunn 

 found that the spread in pitch between notes in a single song might be 

 as great as an octave, but averaged less than half this range. 



A white-throat's song nearly always has at least one change of 

 pitch, and there may be as many as three. Owing no doubt to the 

 quality of the notes and the repetition of the melody, many authors 

 have described the song as musical and A. V. Arlton (1949) uses 

 musical symbols to depict the pattern. Borror and Gunn state, 

 "Songs of the white-throated sparrow are relatively musical, but the 

 birds do not stay on key very well, and the pitch changes in their 

 songs do not follow our musical scale." 



Most songs begin with one or more steady notes and end with 

 a series of similar triplets. Aretas A. Saunders (MS.) provided in- 

 formation on the number of triplets and the length of songs based 

 on notations of 106 songs. His data are bracketed after those of 

 Borror and Gunn (1965), who found from to 7 [0 to 10] triplets with 

 an average of 1.8 [4.4]; song length varied from 1.2 to 6.1 [1.6 to 7.0] 

 seconds and averaged 2.9 [3.7] seconds. Thus, the length of the song 

 is quite variable and this is true even of songs of an individual. If 

 a bird is disturbed it may omit some or all of the final triplets. 



Songs of white-throats vary in a number of respects. Borror and 

 Gunn describe 15 patterns based on the types of notes present and 

 pitch changes through the song. Some patterns were much commoner 

 than others and the proportionate representation of the different 

 patterns varied geographically. The four patterns making up over 

 96 percent of the songs they studied are described here. The com- 

 monest type, accounting for 62 percent of the songs, begins with a 



