Underwater photograph of humpback whales in Hawaii. ©Tsuneo Nakamura.
Humpback whales are probably the best known of all the baleen whales. Humpback whales are rorquals and are found in all parts of the ocean. They spend spring, summer, and fall in high latitudes feeding on rich patches of prey. During the winter they migrate to more tropical areas for breeding and calving. Humpbacks range from 16-17 m (52-56 ft) in length, and females are typically 1-1.5 m (3-5 ft) longer than males. Humpback whales can be identified by their long pectoral flippers that are approximately 1/3 their body length. The top, or dorsal, part of the body is black, but parts of both sides of the flippers and the undersides of the tail flukes are white. Distinctive markings on the underside of the tail flukes are used to identify individual humpback whales. These traits are easy to see because humpback whales often perform spectacular jumps and leaps at the surface.
Humpbacks are best known for their vocalizations that are arranged in complex, repeating sequences with the characteristics of “song” (See How Marine Mammals Communicate Using Sound). Scientists have discovered that these songs are produced by males on the breeding grounds. They contain both tonal and pulsed sounds and change from year to year.
Humpback whale breaching. ©Inger Marie Laursen.
Recent studies have found that humpbacks continue to sing on their feeding grounds. It is thought that singing may function as male breeding displays, male-male social ordering, or a means for spacing reproductively active males. Humpback whales also produce rhythmic “feeding calls” that are usually about 2.5 seconds long at 500 Hz when on the high latitude feeding grounds.