A new study published in the journal Nature Communications Biology suggests that whale songs may actually just be nature's emo croon. Using an 18-year dataset of humpback whale behavior, the researchers noticed that whale song had become an increasingly less successful mating tactic for the male humps as populations have recovered from the height whaling. From the abstract:
As male density increased over time, the use of mating tactics shifted towards more males engaging in non-singing physical competition over singing. Singing was the more successful tactic in earlier post-whaling years whereas non-singing behaviour was the more successful tactic in later years. Together, our study uncovers how changes in both local, and population-level male density resulted in a shift in the frequency, and fitness pay-off, of alternative mating tactics in a wild animal.
The head researcher, Rebecca Dunlop, expanded on this in a conversation with Associated Press:
"It was getting more difficult to actually find singers," said Dunlop, who is based at the University of Queensland in Brisbane. "When there were fewer of them, there was a lot of singing — now that there are lots of them, no need to be singing so much."
[…]
Dunlop speculates that singing played an outsized role in attracting mates when populations were severely depleted.
"It was hard just to find other whales in the area, because there weren't many," she said.
When whales live in denser populations, a male looking for a mate also has to ward off the competition, and singing may tip off other suitors, she explained.
In addition to the obvious takeaway here — that the infamous caoineadh of a whale is really just a cry for loneliness — the study has an interesting breakdown of how and why male whales might use different mating tactics. Those watery leviathans are just like this!
Post-whaling shift in mating tactics in male humpback whales [Rebecca Dunlop & Celine Frere / Nature Communications Biology]
Lonely tunes: Humpback whales wail less as population grow [Christina Larson / AP News]
