485 



highest frequency units in the song — 

 the arpeggio- following the loud rising 

 units in theme 3 (Fig. 10 shows such 

 units from whales II and IV, song 

 types A and B, respectively). The com- 

 plexity of the arpeggios and their vari- 

 ation from song to song are obvious. 



Begionings of Songs 



Following the last phrase of the final 

 theme in either song type A or B, the 

 whale starts the first sound in the next 

 song (which we have labeled the first, 

 and shortest, pulse train of theme 1 ) 

 without any noticeable break in the 

 rhythm of singing. The pause between 

 any two phrases of the last theme is, 

 if anything, longer than the pause be- 

 tween the last phrase of one song and 

 the first phrase of the succeeding song. 

 This fact should make it apparent that 

 not only is our designation of phrase 

 beginnings and ends arbitrary, but so 

 is our choice of the start of a song. 

 It is also possible that what we have 

 designated a "song" may, in fact, be a 

 long segment of a still longer song, 

 but that possibility must await further 

 analysis. 



The criterion we have used here to 

 determine a starting point is influ- 

 enced by our large sample of recorded 

 songs from the years 1969 and 1970. 

 In these songs, the overwhelming ma- 

 jority of starts, stops, and blows occurs 

 at a point corresponding roughly to the 

 starting point we have chosen here. 

 Watlington's tapes include very few 

 records of whales beginning to sing 

 and only slightly more of the ends of 

 song sessions. (Usually the tape ran 

 out, the noise level from passing ships 

 rose to mask the whale sounds, or re- 

 cording was stopped.) Thus the Wat- 

 lington sample is really too small to 

 warrant any conclusion on this point. 

 It is clear, however, that, regardless of 

 where a song may begin, the whale 

 continues the sequence of themes in the 

 same irreversible order (that is, 3, 4, 

 5, 6, 1, 2, 3, 4, 5 . . .). 



Fig. 10. Linear, wide-band spectrograms 

 (upper frequency limit 2 kilohertz, effec- 

 tive filler bandwidth 200 hertz) show the 

 complex and variable structure of the 

 highest notes in phrase 3. Columns 1 and 

 2 are from songs I and 2 of whale II. 

 Columns 3 and 4 are from songs 1 and 

 2 of whale IV. Read sequence of sounds 

 from top to bottom. (The intermediate 

 lower and louder frequency sweeps are 

 omitted here.) 



Evidence that One Whale 

 Is Responsible for a Song 



We have been assuming throughout 

 this discussion that any given song or 

 song session is the performance of one 

 whale. 



The evidence that a song is produced 

 by one whale and not by two or more 

 in alternation ("duetting") follows. In 





long samples of sounds: (i) we never 

 heard anything less than a song (if we 

 had ever heard songs in which themes, 

 phrases, or units were absent but in 

 which there were pauses of appropriate 

 length tQ accommodate the missing 

 piece, we might suspect that two 

 whales cooperate to produce a com- 

 plete song); (ii) no units, or subunlts 

 (excluding what are obviously echoes). 



Song 2 



Song 3 



Whale A 



ong 4 



