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Scientific Name: Megaptera novaeangliae
Category: Cetaceans
Humpback Whales have no teeth. Instead the gums of their upper jaw are covered with a series of strong but somewhat elastic, bristled plates made up of the same material as human hair and fingernails. These plates hang down into their mouth and all together they resemble a moustache or a broom. This feature is called a baleen and whales use it to filter their food from seawater. The Humpback Whale, found in all of the world's oceans, spends much of its time in shallow water. They migrate yearly almost 9,660km (6000 miles) between their summer feeding grounds in the cooler, temperate and polar, regions and their winter breeding grounds in tropical waters. Humpback Whales are known as the acrobats of the ocean. The name "humpback" comes from the way they arch their backs as they breach the surface. They also slap their tails and fins against the surface, sometimes lift a third of their bodies out of the water like a periscope, and swim on their backs with their flippers in the air. These playful behaviors may be part of the way they talk to each other.
Humpback Whales can be black, gray or white and have varying amounts of white on the undersides. As they dive, their tails (called flukes) rise out of the water, exposing distinct dark and white markings. Fluke markings are unique, like human fingerprints, and scientists use them to identify and track individual animals. A series of 14-35 expandable throat grooves, important to the feeding process, extend from their lower jaw back along their midsection. The Humpback Whales have the longest flippers of any whale species. These flippers are white in color, have knobs along their forward edges, and are about 1/3 the length of the Humpback Whale's body (4.6 m or than 15 feet).
Adult males are 16m (52 feet) in length and females are slightly larger than the males. Adults weigh about 27-45 tonnes (30-50 tons). Males reach maturity when they are about 11.6m (35 feet) long and the females at 12m (40 feet) long. The whales mate during the winter in warm tropical waters and during this time, they do not eat, but live off their blubber. After mating, the female gives birth to one calf about 12 months later. Females usually give birth every 2-3 years. The baby calf is 3-4.5m (10-15 feet) long and can weigh up to 2.3 tonnes (2 tons) - that's a big baby! Calves usually nurse until they are one year old and they drink about 100 pounds of milk a day. Humpback Whales have a life expectancy of 45-50 years.
Humpback Whales generally eat krill, plankton, and small fish like mackerel and herring. When they feed, they gulp in large amounts of seawater, fish and small organisms. As they take the water in, their throat grooves stretch out sideways, allowing them to take a really big gulp! Their tongue then squeezes against the inner side of the baleen. This action forces out the water and retains their food in their mouth. Humpback Whales probably consume such large quantities of food because they are seasonal eaters, feeding only during the summer months in high latitude waters. To maximize their food sources, Humpback Whales engage in a cooperative hunting method called bubble net feeding. One whale swims in a circle under a school of herring while blowing bubbles. As the bubbles rise, they form a column or cylinder from which they herring cannot escape. The other whales involved vocalize (grunting, moaning and screaming) around the herring, which frightens them, and causes the fish to form a tight ball as they rise to the surface. The whales then spiral to the surface with their mouths wide open, often capturing the entire school in one or two gulps!
Male Humpback Whales love to sing. Their songs are very complex, with distinct melodies made up of grunts, moans, squeaks, and clicks. Some males repeat the same song again and again for hours. The songs are unique to specific oceans, regions and individual populations and can change from one breeding season to the next.
The major predators of the Humpback Whales are killer whales and humans. The whales were hunted during the 19th and early 20th centuries for their blubber, oil, whalebones and meat. Today Humpback Whales can be part of the bycatch in nets and longline fishing hooks. The whales are also affected by ocean pollution, especially plastics and toxic chemicals. As of 2008, the IUCN Redlist considers the Humpback Whale as "least concerned" from a conservation standpoint. Many companies run whale watching tours off the coast of the United States and Canada and it is exciting to see the breaching of a Humpback Whale, as they can come totally out of the water.
Research Links Related to Humpback Whale:
- American Cetacean Society -- Humpback Whale
Physical description, color, fins and flukes, range map and status. - BBC -- Humpback Whale
Videoclips, underwater photography showing throat grooves, whale song. - Discovery of Sound in the Sea -- Humpback Whale
Sounds of Humpback Whale, videos of whales swimming, spectra of sound, explains physics of whale songs.
- Marinebio -- Humpback Whale
Description and behavior with a good illustration of Humpback Whale.
- Museum of Zoology -- Animal Diversity Web -- University of MichiganHumpback Whale
Basic facts with a discussion of behavior, communication and perception (echolocation)
- National Geographic -- Humpback Whale
Photos and mulitmedia audio, fact sheet. - NOAA -- Humpback Whale
Covers physiology/description, habitat, distribution, population trends and threats
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