With the humpback whale population recovering off the coast of Australia, competition has increased between males, who have reduced their song and started fighting to attract females, a study reveals.
Scientists led by the University of Queensland (Australia) analyzed almost two decades of data on the behavior of humpback whales and published the results Thursday in the journal Communications Biology.
The song of humpback whales, emitted by males, is among the most complex in the animal kingdom. While its exact function is debated by scientists, it is accepted by the scientific community that this song allows a dominant male to monopolize a female to become what is called a main escort.
In 1997, singing males were “almost twice as likely to try to mate with a female than non-singing males,” said researcher Rebecca Dunlop, one of the study’s authors.
However, by 2015 the situation had changed and non-singing males were nearly five times more likely to be seen trying to reproduce than singing ones.
For the researcher, this is a “quite big” change in behavior and suggests that humans are not the only ones subject to “big social changes in terms of mating rituals.”
Scientists believe that the change occurred progressively as the number of individuals of the species recovered, after the widespread cessation of whaling in the 1960s.
With more males, the competition is fiercer and the last thing one of these wants is to announce, with his song, that there is a female in the area, since it can attract other males, in which case they must compete or leave the area. Dunlop explained.
Among humpback whales, physical aggression tends to take the form of lunges and attempted headbutts, which can result in injury, leading males to “weigh the costs and benefits of each tactic.”
The researcher added that “it will be fascinating to see how the mating behavior of whales continues to be shaped in the future.”
Source: TSF
