Rorquals: Balaenopteridae

Physical characteristics: Humpback whales grow to between 38 and 49 feet (12 to 15 meters) in length and weigh between 27 and 33 tons (25 to 30 metric tons). The tail can be 18 feet (5.5 meters) wide. They are black except for their underside, flippers, and throat, which are white. Their head, jaw, and flippers are covered with bumps. Each bump has at least one hair growing out of it. Scientists do not know what these bumps or hairs are for. The humpback whale has the longest flippers of any whale.

Geographic range: Humpback whales live in the Pacific and Atlantic Oceans.

Habitat: Humpback whales spend the cooler months closer to the equator and then migrate towards the north or south pole for the warmer months.

Diet: Like most rorquals, humpback whales eat krill or small marine animals that they catch by filtering large quantities of water through their baleen. While the largest part of their diet is krill, the humpback whale also eats a variety of small fish. Each whale eats about 1.5 tons (1.4 metric tons) of food a day.

Behavior and reproduction: Humpback whales tend to gather in groups of two to five. Not only are they known for their acrobatic

Female humpback whales nurse their young for about one year, and have a new calf about every other year. (V. & W. Villoch/Bruce Coleman Inc. Reproduced by permission.)

ability to leap out of the water and slap the water with their tail and flippers, but humpback whales do some of the most complex and intricate singing of any mammal. These songs last about twenty to thirty minutes and are repeated for hours. The North Atlantic whales all sing the same song, and it is different from the song the North Pacific humpback whales sing. Females are pregnant for twelve months and nurse their young for another year after birth. They usually have a new calf every other year. Humpback whales can live up to seventy-five years.

Humpback whales and people: Because humpback whales tend to stay closer to the land than other rorquals, they were hunted heavily. Although their numbers have decreased substantially, the humpback whale is less likely to go extinct than several other whales.

Conservation status: Humpback whales are considered Vulnerable. ∎