The Blue Whale
Blue whales are the largest animals ever known to have lived on Earth. These marine mammals are up to 30 meters long and weigh up to 200 tons.
Blue whales feed on a diet composed of tiny shrimp like animals called krill. During certain times of the year, a single adult blue whale consumes about 4 tons of krill a day.
Blue whales feed by first gulping an enormous mouthful of water, expanding the pleated skin on their throat and belly to take it in. Then the whale's massive tongue forces the water out through the thin, overlapping baleen plates. Thousands of krill are left behind—and then swallowed.
Blue whales look true blue underwater, but on the surface their coloring is more a blue-gray. Their underbellies take on a yellowish colour from the millions of microorganisms that live on its skin. The blue whale has a broad, flat head and a long, tapered body that ends in wide, triangular flukes.
Blue whales live in all the world's oceans occasionally swimming in small groups but usually alone or in pairs. They often spend summers feeding in polar waters and undertake lengthy migrations towards the Equator as winter arrives.
Blue Whales are the world’s most endangered creatures and they should be protected.
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