More than 20 years have elapsed since the first detailed description of humpback whale song (Payne and McVay, 1971;Winn, Perkins and Poulter, 1971) and despite considerable attention, the function of song remains elusive. In this paper, we review the literature on humpback whale song and describe general methods used to collect data on free-ranging whales. Then, we present the results of three current studies that have used different methods to shed light on the function of whale song.

Humpback whales Megaptera novangliae migrate annually between high-latitude waters in summer and low-latitude waters in winter. Feeding occurs primarily in summer waters. The behaviuor of whales (Herman, Forestell and Antinooja, 1980; Tyack, 1981; Darling, Gibson and Silber, 1983; Glockner and Venus, 1983; Becker and Herman’1984; Mobley and Herman’1985) and their reproductive physiology during the winter months ( e.g’ Chittleborough, 1955, 1958,1965) suggests that reproductive activities are dominant during the winter’ although copulation has not been documented.

Singing peaks during the winter months (Winn and Winn’1978; Thompson and Friedl, 1982; Helweg, 1989), although it has been reported occasionally late in the fall on the feeding grounds (Matilla, Guinee and Mayo,1987;McSweeney, Chu, Dolphin and Guinee,1989) and in migratory waters (Tyack and Whitehead, 1983; Kaufman and Jenkins,1985). The correlation of song production and seasonal gonadal activity suggests that it plays a role in the mating system,

Humpback whales obvious sexual dimorphic features. However, the singing whales that have bee sexed have proven to be male (Winn, Bischoff and Taruski, 1973; Glocker’1983). The role of a singer has been shown to be interchangeable with the role of “escort”- the name given to one or more adult whales seen accompanying a cow with calf (Herman and Antinoja,1977; Tyack,1982; Darling et al.’ 1983; Tyack and Whitehead’1983). All esdcort whales sexed, thus far, also have been identified as males (Glocker-Ferrari and Ferrari,1981; Glockner,1983). In this paper we assume that are singers re mature males.