480 



Fig. 5. Whale IV, recorded by Wallington 12 April 1961. This is an example of a 

 different song lype (lype B) from the previous three examples. The poor signal-to-noise 

 ratio of the recording caused the spectrograms for the highest frequency, lowest inten- 

 sity signals to be quite faint. At the end of song 2. the whale slopped singing. This was 

 actually the fourth and last consecutive song Watlington recorded from this whale on 

 this occasion, and thus also indicates a true ending. 



while the pair were submerge* He 

 was using no hydrophone, the sounds 

 coming directly through the bottom of 

 the boat. Observations such as these 

 have removed most of our doubts that 

 what we have been analyzing arc 

 humpback sounds; yet the great vari- 

 ability of the sounds still leaves us with 

 residual reservations about ascribing to 

 one species (the humpback) all of the 

 sounds we are analyzing here. 



Analysis of Humpback Sounds 



On first hearing humpback vocaliza- 

 tions, one has the impression of an al- 

 most endless variety of sounds. Spec- 

 trographic analysis shows, however, 

 that all prolonged vocalizations occur 

 in long, fixed sequences and are re- 

 peated with considerable accuracy 

 every few minutes. Because one of the 

 characteristics of bird songs is that they 

 are fixed patterns of sounds that are 

 repeated, we call the fixed patterns of 

 humpback sounds "songs." The prin- 

 cipal differences between bird and 

 humpback songs are that bird songs 

 usually last for a few seconds, while 

 humpback songs last for minutes; and 

 one song of a bird is usually separated 

 from the next by a period of silence, 

 whereas humpback songs are repeated 

 without a significant pause or break in 

 the rhythm of singing. 



The term "song," as used in discus- 

 sions of sounds made by animals, has 

 received considerable attention. In one 

 case, no fewer than nine pages of 

 a comprehensive glossary by Brough- 

 ton (see II) are devoted to a de- 

 tailed discussion of the many uses, mis- 

 uses, and meanings of "song." Brough- 

 ton finally arrives at three meanings, 

 or categories of meanings, of the term 

 "song," which he characterizes as sensii 

 laiissiino. sensii slriclo, and sensu 

 strictissimo. The median of these three 

 (semu stricio) is defined as "a series 

 of notes, generally of more than one 

 type, uttered in succession and so re- 

 lated as to form a recognizable se- 

 quence or pattern in time." By that 

 definition (and by Broughton's other 

 two as well), we feel justified in using 

 the term "song" to describe repetitive 

 sound patterns of humpback whales. 

 In describing the humpback whale 

 song, we will adhere to the following 

 designations. The shortest sound that 

 is continuous to our ears when heard 

 in "real time" will be called a "unit." 

 (Some units when listened to at slower 



