A study led by the University of St Andrews in Scotland found a new feeding technique, brought on by the need to find new prey, has spread to 40 per cent of a humpback whale population.
Humpback whales in the Atlantic Ocean off New England were forced to find new prey after stocks of herring, their preferred food, crashed in the early 1980s.
A new hunting technique -- hitting the water with their tails to herd prey -- has spread through the population by cultural transmission, a university release reported Thursday.
"Our study really shows how vital cultural transmission is in humpback populations -- not only do they learn their famous songs from each other, they also learn feeding techniques that allow them to buffer the effects of changing ecology," St. Andrews biologist Luke Rendell said.
Humpbacks around the world normally herd shoals of prey by blowing bubbles underwater to produce 'bubble nets," but the new technique, dubbed "lobtail feeding," involves the whales hitting the water with their tails before diving to produce the bubble nets.
The innovation is specific to a particular prey -- sand lance -- because its use is concentrated around Atlantic spawning grounds where the sand lance can reach high abundance, the researchers said.
The findings strengthen the case that cetaceans -- whales and dolphins -- have evolved sophisticated cultural capacities, the researchers said.