Since their discovery, the haunting underwater songs of the whale have fascinated many people. Although released as a record and woven into human music by groups like the Paul Winter Consort, it is only in the last few years that experts have begun unraveling the riddle of the whale's song.
The latest results of these efforts were reported at the annual meeting of the American Association for the Advancement of Science held here.
The operatic superstar of the whale family is the humpback. Solitary singers float just below the surface, flukes and fins drooping, and concertize for hours , pausing only for breath. The result is the most complex animal song known.
According to Katherine Payne, who with her husband Roger has pioneered in the study of whale behavior, humpbacks manage to fill the sea lanes with eerie melodies that range from timpani-like booms to piccolo-shrill whistles, without expending any precious air.
The Paynes, associated with the New York Zoological Society, have recorded hundreds of humpback songs from Hawaii, Baja California, and Bermuda. Mrs. Payne's analysis has turned up some remarkable and unexpected results.
The humpback's songs have definite structure, she has found. Each song is made up of recognizable "themes" that always appear in the same order. There are often transitions between themes which are improvisitional in nature.
Humpbacks have a number of songs in their repertoire and move from one song to the next, often without pausing. Song sessions typically last several hours. As befits their size, humpbacks appear to have developed a Wagnerian-like tradition.
These whales sing predominantly during the mating season. Singers are always solitary and presumably male. This latter point is suggested by the fact that all six singers that researchers have sexed so far have proved to be male and by the fact that whales identified as singers have been seen as escorts to a cow and calf but never as a cow, according to James Darling of the University of California at Santa Cruz, who has been studying humpback behavior.
Further, all the singers in the breeding area sing the same set of songs, Mrs. Payne says. But these songs are not fixed like those in many songbird species. Instead, they are continually evolving. Through a given season and over the years, the humpbacks continually modify their melodies. Certain themes grow in length, complexity, and structure while others become increasingly abbreviated and finally vanish.Sometimes one "note" is systematically replaced by another. The entire repertoire appears to go through cycles of greater length and greater improvisation.
This pattern has certain parallels with some songbirds that also vary their tunes. In these birds, it is the dominant male who alters the composition and the rest follow his lead. Among whales "we have no idea if there is such a ringleader," Mrs. Payne says.
Like the songbird, or the troubador singing outside his lady's window, it appears fairly certain that the humpback's virtuosity involves courtship. Peter L. Tyack of Rockefeller University has been tracking the movements of humpback singers in Hawaii in an attempt to understand the import of their songs. He has found a suggestive pattern.
First, whales begin singing when they are alone. Singers tend to space themselves about five miles apart and invariably approach cetacean passersby. When they take up company with another whale, they stop singing.
Not all whales are as musical as the humpback, however. This is illustrated by the study of killer whale vocalizations reported by John K. B. Ford of the University of British Columbia. Killer whales have a totally different life style from the humpbacks. They live in close-knit and extremely stable extended families called pods.
Possibly as a result they have no elaborate song like their larger, more solitary cousins. Each pod, however, utters 10 or so recognizable calls.