At Howard's cue, the boat pilot cuts the engine. Before Howard has a chance to finish unpacking an underwater microphone called a hydrophone, extraordinary sounds fill the silence. I watch the still gray water, not a little incredulous. Certainly, the whalers must have heard the same ethereal medleys. Sound most certainly reverberated better through the wooden hulls of their rowboats than it does through our motorized craft of fiberglass.
Sound travels better in water than in air.
Our singer can likely be heard by other whales more than 50 miles from here. Singers assume a distinct posture, hovering about 50 feet below the surface with flippers outstretched, head down and tail flukes pointing up. The whales in this bay are all singing variations of the same song, although not in unison. In fact, all of the humpbacks in a particular winter breeding ground sing the same song, regardless of where they go in the summer to feed. The song that we're hearing being sung here and now in the Indian Ocean differs from the one that is sung, for instance, by humpbacks who breed in the Atlantic.