Humpback whales may have a true culture that involves sharing techniques to improve hunting and feeding. That’s the finding put forward in a new study published this week in journal Science, which is based on data collected over 27 years by the Whale Center of New England in Gloucester, Massachusetts.
Luke Rendell, a University of St. Andrews biologist who worked on the study, pointed out that we already have evidence that humpback whales have a culture of sharing new songs over time. Now the team of researchers has analyzed the evidence from the Gulf of Maine to prove that the same species also shares hunting tips.
Humpbacks hunt using a technique called bubble-net feeding, which involves blowing bubbles to make a net that traps the fish. Then the whale can plunge open-mouthed through the trapped school to gulp down plenty of food at once.
Herring fishing stocks collapsed in the Gulf of Maine in the 1970s. In 1980, a humpback whale came up with the idea of slapping the water with its tail fluke before going forward to blow bubbles.
That technique, called lobtail feeding, allowed the whale to catch sand lance fish more effectively. Sand lance populations soared when the herring vanished.
In 1980 only one whale used the technique. By 2007, 37 percent of the humpback whales used it.
But did each whale have to reinvent the wheel for itself? Or the whales actually learn by being influenced by the actions of a friend or companion?
The researchers’ analysis showed that up to 87 percent of the humpback whales had learned from another humpback, instead of independently coming up with the idea.
Humpback whale song research goes back to at least 1971, when researchers Roger Payne and Scott McVay first published a technical description of the complex song of the male humpback. (Females don’t sing.) Over time, scientists discovered that the songs are constantly changing, with certain styles coming and going into fashion, so that a given humpback whale population will share the same version of their song during the same time.
Now there’s evidence that humpback whales share hunting culture too.
[humpback whale photo courtesy NOAA]