Humpback whales most commonly use songs in breeding season, but Duke researchers found that the whales also sing while hunting for food.
The study exhibits whales’ ability to multitask, showing that the marine creatures use their time searching for food as an additional opportunity to attract a mate. Published in scientific journal PLoS ONE this December, the study shows that breeding and hunting are not necessarily separate acts.
“They need to feed. They need to breed. So essentially, they multi-task,” said study co-author Ari Friedlaender, an assistant research scientist at the Nicholas School of the Environment, in a Duke news press release. “This suggests the widely held behavioral dichotomy of breeding-versus-feeding for this species is too simplistic."
Researchers from Duke, the U.S. Naval Postgraduate School and the University of California at Santa Barbara used noninvasive, multisensor tags to record the whales’ underwater movements and vocalizations throughout May and June 2010. The tags were attached to 10 whales along the Western Antarctic Peninsula using suction cups.
In two cases, the tags recorded intense and continuous whale singing whose organization and structure signified a typical mating display. In one case, however, a sensor indicated a whale, or close companion, was lunging for food during an almost hour-long song bout.
Although singing for mating purposes is the most common, it is known that humpback whales are known to sing on other occasions besides breeding. Sometimes humpback whales will sing while leading mother-calf pairs along migratory routes.
Even though the reasons why these whales sing is not thoroughly understood, it is known that songs sung in breeding grounds are different in their duration, phrase type and theme structure when compared to those heard at other locations and times.