A lone whale, with a voice unlike any other, has been wandering the Pacific for the past 12 years, American marine biologists said Wednesday.
Using signals recorded by the U.S. Navy to track submarines, they traced the movement of whales in the Northern Pacific and found that a lone whale singing at a frequency of around 52 hertz has cruised the ocean since 1992.
Its calls, despite being clearly those of a baleen, do not match those of any known species of whale, which usually call at frequencies of 15 to 20 hertz.
The mammal does not follow the migration patterns of any other species either, according to team leader Mary Anne Daher.
The calls of the whale, which roams the ocean every autumn and winter, have deepened slightly as a result of aging, but are still recognizable.
The study, by scientists at the Woods Hole Oceanographic Institution in Massachusetts, was published in the December issue of the journal Deep-Sea Research I and reported in the New Scientist magazine.
