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Megaptera novaeangliae [meg up ter' uh nO' vE ang' lE dE]
The humpback whale is one of the largest baleen whales, with adults being 40-50 feet long and weighing 25-40 tons. It is distinguished from other whales by an obvious hump behind the head, black dorsal coloring, wavy rear edges on the tail flukes, and the presence of rounded, bump-like knobs on the top of the head, each containing at least one stiff hair. Its pectoral fins are also unusually long, being 1/4 to 1/3 the length of the entire body.
The dorsal fin and fluke of every individual humpback whale is unique, just as every individual human has unique fingerprints.
Humpback whales are found in all oceans of the world, with each major oceanic zone (North and South Atlantic, North and South Pacific, and Indian) having its own distinct population.
Humpbacks feed on krill and small fish, consuming up to 1-1/2 tons of food per day. They hunt by direct attack, by stunning prey by hitting the water with pectoral fins or flukes, and by "bubble netting," which involves a group (pod) of whales circling around a school of fish and blowing bubles to create a sort of net that keeps the school confined within a small area. Once the prey has been confined, individual whales swim up through the school with mouths open and swallow hundreds of fish at a time.
Humpbacks (except for those in the Indian Ocean) migrate to tropical and sub-tropical waters to breed, with some populations covering up to 16,000 miles each year. The peak birth months being January, February, July, and August. They do not feed during the breeding season, living off fat reserves.
Once at the breeding area, males will gather in groups and compete for females through displays to the females and dominance confrontations between the males.
After a gestation period of about 12 months, a single calf is born that is 10-15 feet long and weighs up to a ton. The calf will stay with its mother until being weaned at about one year. Sexual maturity is reached at 6-10 years. Females typically only breed once every two to three years.
Humpbacks are active, acrobatic whales who can, and often do, throw themselves completely out of the water, and they love to swim on their backs with both flippers in the air. They also love to "tail lob" and "flipper slap," actions which make them very popular with whale watchers.
Although all whales are known to communicate with "grunts," "barks," "squeals," "snorts," etc., every population of humpback whale has its own distinctive "song" that can last as long as 20 minutes and which may be repeated for hours at a time. Studies of individual whales that have for one reason or another moved from one geographic population to another have shown that the "immigrant" whale will gradually learn the "song" of its new area.
Unlike many other whales, humpbacks are generally solitary, only coming together during the breeding season and for cooperative hunting.
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This page was last updated on September 02, 2018.