How do humpback whales sing?
For a long time, it was believed that whales cannot sing since they do not have functional vocal cords. Researchers believe that the sounds are produced by pushing one air stream in different directions within their respiratory tract, and another study suggests the thorax may be used. In the 1950's, their singing was discovered when the United States Navy experimented with hydrophones. From then on, their singing has been analyzed by scientists, who describe it like this: the whales go to a depth of between 45 & 130 feet and get into a certain position when they sing. They may remain motionless with their head downward, or are sometimes seen traveling, either alone, or with another male and a small percentage are observed traveling with a female and her calf. Kent Noonan, our engineer, made the following experiences: "There was a mother/baby/escort pod traveling toward me while I was out in my kayak with my hydrophone. The mother and baby veered to one side and swam by me underwater. The male swam directly under me only a few feet down and continued singing uninterrupted. I was listening as he approached and it became so loud I thought my ears would burst. I tore the headphones off and could still hear it very loud as he passed under me only about 8 feet down. Another time I saw a large male singing while I recorded nearby. He was slowly swimming in a large circle under a mother and baby. He went in a circle perhaps 100 yards across at a rate of about 15 minutes to go around it, about 50 to 100 feet down. This is the recording I call "Kalama Lullaby" because it seemed he was making a cradle of sound for the mother and baby to feel protected in, while they snuggled on the surface in the sun"
