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Science The controversial sale of 'Big John,' the world's largest Triceratops. Sometimes they even help each other hunt. They can travel around 3, miles 5, kilometers between their breeding and feeding grounds on a regular basis. The longest ever recorded migration was 11, miles 18, km , a trip that went from American Samoa to the Antarctic Peninsula. Humpbacks often propel themselves above the water and then splash back down, according to National Geographic.
This is called breaching. Some scientists think that they may do this to splash off parasites, but they may just do it because it's fun. They also slap the water with their tails or flippers, according to the NOAA. These behaviors may be used to communicate with one another. They may also be used to show dominance and health during mating season, according to Whale Facts.
Humpback whales are known for their haunting songs, which are complex sequences of moans, howls and cries that often continue for hours, according to National Geographic. Only male whales sing, so scientists think they are trying to attract potential mates. A male may sing for hours, repeating the song several times. All males in a population sing the same song, but the songs of each population are different. Songs gradually change from year to year.
Songs can be heard 20 miles 30 km away, according to the NOAA. The whale sounds typically have an audio frequency between 80 and 4, hertz , according to National Geographic. In , researchers reported hearing humpback vocalizations around 40 hertz. The low limit for human hearing is 20 hertz. But these marine giants don't just bellow out loud songs. Turns out, they also have "indoor voices" when the situations calls for it, according to a study published April 25, , in the journal Functional Ecology.
The researchers found that during their migrations of calves and their mothers to feeding grounds, the young ones made very quiet vocalizations; these calls were about 40 decibels quieter than those created by singing whales and up to 70 decibels lower than social vocalizations of adult humpback whales.
The researchers suspect the "whale whispering" may be a way for the mother-calf pairs to stay under the radar of nearby killer whales. Humpback whales are baleen whales. Rather than teeth, they have to fringed overlapping plates hanging down from each side of the upper jaw, called baleen plates.
The plates are made of keratin, which is the same thing human hair and nails are made of. Baleen plates are black and about 30 inches 76 cm long, according to the NOAA. Credit: Rob Harcourt. Humpbacks have baleen, a type of filter instead of teeth that allows them to capture krill and other small fish. Credit: W. The paper said it remained unclear whether the formation of super-groups was linked to changes in the type or density of prey available, either along the migratory route or in the feeding grounds of the previous summer.
While the super-groups might attract the public, Professor Harcourt warned would-be whale watchers in boats to steer clear. Humpbacks off Sydney in July numbers of the giant mammal are growing rapidly and are believed to be approaching pre-whaling days. Credit: Vanessa Pirotta. Boats are required to stay at least metres away from whales and 50 metres from dolphins. No more than three boats are permitted within so-called caution zones of metres of a whale at any one time, according to Australian guidelines.
Humpback whales had recovered much faster than other species, including blue whales, which had been detected forming large groups off the California coast, Professor Harcourt said.
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