DEEP THINKERS Chapter Two
HUMPBACK WHALE Megaptera novaeangliae
Humpback whales migrate seasonally from the tropics to their northern feeding grounds, and during the summer months they must feed intensely in preparation for this migration. These magnificent whales are renowned for their acrobatic aerial breaching, and their beautiful yet complex songs, performed by males during courtship. Humpback whales are best known for their magical songs, which travel for great distances through the world’s oceans. These sequences of moans, howls, cries, and other noises are quite complex and often continue for hours on end. Scientists are studying these sounds to decipher their meaning. It is most likely that humpbacks sing to communicate with others and to attract potential mates. These whales are found near coastlines, feeding on tiny shrimp-like krill, plankton, and small fish. Humpbacks migrate annually from summer feeding grounds near the poles to warmer
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HUMPBACK
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winter breeding waters closer to the Equator. Mothers and their young swim close together, often touching one another with their flippers with what appear to be gestures of affection. Females nurse their calves for almost a year, though it takes far longer than that for a humpback whale to reach full adulthood. Calves do not stop growing until they are ten years old. Humpbacks are powerful swimmers, and they use their massive tail fin, called a fluke, to propel themselves through the water and sometimes completely out of it. These whales, like others, regularly leap from the water, landing with a tremendous splash. Scientists aren’t sure if this breaching behavior serves some purpose, such as cleaning pests from the whale’s skin, or whether whales simply do it for fun.
Length - 16 m Wieght - 40 Tons (Max.) Type - Baleen LIfe span - 45~50 years Food - Krill, plankton & small fish
HUMPBACK
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A Humpback’s brain contains a type neuron that was believed to be unique only to humans and great apes
HUMPBACK
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WORKING TOGETHER
Humpbacks are very intelligent and some groups use a complex method of trapping the fish which only works with clever cooporation from every whale.
HERDERS Circle the fish with flashing fins, keeping the shoal contained and preventing its escape.
CALLER The caller dives below the shoal and emits a deafening cry. As loud as a rocket launch, 180 decibels of sound pressure blasts through the water. In an attempt to escape from the noise, the panic-stricken fish are driven upwards
RING LEADER Taking up position above the herring, it begins blowing out a stream of air to create a fizzing net of bubbles. The shoal is prevented from dispersing by the herders, and driven up by the caller right into the bubble-net
Then all the whales gather underneath the fish trapped in the net. With mouths wide open, the A-team burst through the surface, engulfing their prey. By hunting together like this, each whale can catch up to half a ton of herring a day.
BOTTLENOSE DOLPHINS Eubalaena australis
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Bottlenose dolphins are well known as the intelligent and charismatic stars of many aquarium shows. Their curved mouths give the appearance of a friendly, permanent smile, and they can be trained to perform complex tricks. In the wild, these sleek swimmers can reach speeds of over 18 miles (30 kilometers) an hour. They surface often to breathe, doing so two or three times a minute. Bottlenose dolphins travel in social groups and communicate with each other by a complex system of squeaks and whistles. Schools have been known to come to the aid of an injured dolphin and help it to the surface. Bottlenose dolphins track their prey through the expert use of echolocation. They can make up to 1,000 clicking noises per second. These sounds travel underwater until they encounter objects, then bounce back to their dolphin senders, revealing the location, size, and shape of their target. When dolphins are feeding, that target is often a bottom-dwelling fish, though they also eat shrimp and squid. These clever animals are also sometimes spotted following fishing boats in hopes of dining on leftovers.
BOTTLENOSE
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Length - 4 m Wieght - 500 Kg Type - Porpoises LIfe span - 45~50 years Food - Small fish
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Bottlenose dolphins are found in tropical oceans and other warm waters around the globe. They were once widely hunted for meat and oil (used for lamps and cooking), but today only limited dolphin fishing occurs. However, dolphins are threatened by commercial fishing for other species, like tuna, and can become mortally entangled in nets and other fishing equipment. All dolphins, including the bottlenose, are porpoises. Although some people use these names interchangeably, porpoises are actually a larger group that also includes animals like the orca and the beluga whale. Bottlenose dolphins have been observed to breach up to 16 feet (4.9 meters) out of the water, landing with a splash on their back or side.
BOTTLENOSE
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Scientists think that we will be able to talk to Dolphins in 5 years