Blue Whale

    The blue whale is not only the biggest whale living today, the blue whale is the biggest creature ever to have lived on Earth. They are mind bogglingly gigantic; much larger than any of the dinosaurs. Blue whales and the other ocean giants live their whole lives in seawater.

    Blue whales commonly reach the colossal length of 29m, that's roughly as long as three London red double-decker buses parked end to end. Blue whales in the Southern Hemisphere are generally larger than those in the Northern Hemisphere and female blues are larger than males.

    The longest blue whale on record is a female measured at a South Georgia whaling station in the South Atlantic (1909); she was 33.58m. The heaviest blue whale was also a female hunted in the Southern Ocean, Antarctica, on 20 March 1947. She tipped the scales at 190 tonnes which is equivalent to about 30 elephants or 2500 people.

    Blue whales are now extremely rare due to uncontrolled commercial whaling. Some populations could be endangered to the point of extinction.

The main idea of the third paragraph is ....