Page 12 - OAS Magazine Q2 Summer

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PHOTOS BY: DON HURZELER AND VANESSA MIGNON
human ears. That’s because all blue whale groups make calls at sound frequencies between 10 and 40 Hz. (The lowest frequency a human can perceive is 20 Hz.) Blue whale sounds at the lower end of the auditory band need to be reproduced a significantly faster speed to even be registered by human ears.
Indeed, the sounds of large baleen whales have impressed scientists for years. Humpback whales, with their melodic songs and assortment of creaks, grunts, moans and belches, rank among the sea’s noisiest creatures. The booming, seductive songs sung by finback whales during periods of mating have earned them the reputa- tion as the “Barry White” of the deep.
Although scientists have a better understanding of which whales produce which sounds, they are still unsure of what the sounds mean. Some people think the songs of humpbacks are elaborate mating calls, while others believe that the singing humpbacks are warning others to stay away. Dr. William Watkins of the Woods Hole Oceanographic Institution, a pioneer in marine mammal bioacoustics, believed that the songs serve a few dif- ferent purposes, ranging from attracting a mate to keeping track of one another. “In an ocean, where there’s miles and miles of water and nothing else, sound is the way you notice things,” said Watkins, who passed away in 2004. “It’s how you keep track of where your friends are.”
Watkins, who began studying whale bioacoustics at Woods Hole more than 40 years ago, said that that these communication systems vary wildly from species to species. He believed that part of the confusion had been