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Tuesday, March 2, 2010


Using similar methods as Ornithologists, Marine biologists have been studying the meaning of humpback whale songs for years, but only in November of 2009 was any significant proof discovered to show that they are used for communication between males when it becomes time for mating. Although both males and females have songs, the male song, that is identified by a series of repeated chirps and wails has far greater intricacy than the stable repeated harmonic of the female song. The more complicated male song suggests that they have a more developed speech pattern than the females. This could be due to the incredible amount of communication needed in the competitive game for a female’s attention when it comes to mating. Humpbacks tend to be solitary animals, and although it is widely believed that humpback whales are monogamous lovers, scientists have found that they actually tend to be widely promiscuous, and only have short “associations,” with females, when they swim together, which can last for either a few hours or to a few days. When a group of male humpbacks approach a female humpback, a competitive pod is created. These pods tend to move very quickly and are very animated as the males will often be violent with each other to the extent that the fights will often result in bloodshed. Their goal may be to obtain the position closest to the female being fought over. Evidence suggests that perhaps the whale in that position will be the one who will eventually mate with the female . However, this suggestion cannot be stated as fact, as scientists are yet to ever see humpbacks mate.





To record the whales that led to the discovery that male humpbacks use their songs for communication, Danielle Cholewiak of the Stelwagen Bank National Marine sanctuary, dropped recorders into the waters around the island of Socorro. After about a month, she was able to analyze the recordings made and determine the whale’s position and their songs behavior. It was found that when a male sings alone, their song is more steady and even, as opposed to being more animated and changing when another whale was present. If the two whales stayed together, their songs would be adjusted so that the pair would sing the same theme. Although in the past, the use of sound recordings as variables in experiments have been deemed unuseful, Cholewiak found that when she played simplified recordings of whales own songs in the water, the males listening made their singing more even. With the information gathered in those months, Cholewiak was able to come to the conclusion that when male humpbacks meet each other, their songs change.

Example of a humpback Whale Soundwave

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