Humpback Whales July 17, 2007 1:51 PM
Graceful and magnificent, humpback whales inspire awe in young and old alike. These marine mammals travel great distances to take advantage of the best breeding grounds and feeding spots. North Pacific humpbacks, for example, mate and give birth in Hawaii and then travel to Alaska each summer to feed.
These gentle giants are famous for their singing abilities -- belting out seductive ballads to attract mates or to challenge other would-be suitors. But they also have other talents. Their unique hunting skill, called bubblenet feeding, involves a group of humpbacks working together to capture schools of herring. Each whale has a particular role in the process: One whale swims in a circle while blowing bubbles under a school of herring. When the bubbles rise, the school of herring can not escape and form into a tight ball in the center. Other whales vocalize -- grunting or screaming -- to scare the herring to the surface. The whales then rise with their mouths wide open to capture large amounts of fish.
Trek across the oceans with these astounding creatures and discover more revealing details about their wonder-filled, watery ways.
U.S. Endangered Species Act of 1973.
NMML has done quite a bit of work relating to humpback whale stocks: You can read more about humpback whale stocks in the NMFS Alaska and Atlantic stock assessment reports.
flipper and fluke slapping and tend to breach more than any other baleen whale species.
How well can a humpback whale see or hear?
It is thought that baleen whales (including humpback whales) have excellent hearing, especially at low frequencies, which is valuable in the dark ocean environment where vision is less useful.
What do humpback whales eat?
Humpbacks are baleen whales which means they filter their food through baleen plates. They consume krill, anchovies, cod, sardines, mackerel, capelin, and others sorts of schooling fish.
Some humpbacks have a very unusual way of catching their food. They make nets to catch their prey called "bubble nets" with the air that they release from their blow holes. The whales dive deep then swim up in a spiral pattern, all the while releasing a steady stream of bubbles. As the bubbles rise they form a bubble cage which traps the fish or plankton that the whales are pursuing. Then the whales swim up through the center of the bubble cage with their jaws open and capture a great gulp of food.
How do humpback whales have their young?
Humpback whales are probably old enough to mate at about 7 years of age. Females are pregnant for about 11 to 12 months and get pregnant approximately every two to four years. Calves are born able to swim and can grow 1.5 feet (0.5 meters) per month while nursing. Females nurse their new born calves in warm, shallow water.
Humpbacks have very complicated courtship behaviors and many male humpbacks can surround a female and compete with each other to get close to the female. Sometimes the competition involves males lunging at and bashing into each other. At the end of the mating and calving season, humpback whales migrate to cold, productive waters to feed.
How long do humpback whales live? Why do they die?
Because of an absence of teeth (which can be used to estimate age in other mammals), it is difficult to tell the age of a humpback whale. Li
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VIDEO July 17, 2007 1:57 PM
Watch whales use bubblenet feeding technique. - Go to the following link and click on video.
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